OH Yeah! Gear Pump repair part 2
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- Опубліковано 13 вер 2019
- Welcome to part two gear pump rebuild for the K&T mill. It didn't go the way I wanted but it did go the way I expected. Guess we may have a part 3 coming soon. If you would like to make a onetime shop donation or monthly follow the link below to my PayPal
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/ stevesummers - Наука та технологія
Put a check valve in that suction line. Simple fix.
Yes oil can't leak back to sump and I use it on dieselpumps witch are not self primed.
Yes a simple old brass flapper valve in the suction line. But it must be installed horizontally. So a 90 degree bend then the flapper valve then another 90 degree to the screen. This will give the easiest suction threw the valve. ( the flapper hanging vertically) This should keep coolant primed in the pump.
But be were if the pump can be run backwards you will have a hydraulic lock that can break things.
@@johnlemmey7698 A ball type can run vertically and just replace that suction tube. McMaster stock item.
Rambozo Clown that would be my suggestion too. The pump works fine,good flow and pressure, so any work on the gears would be a waste of effort. Even with new gears there is no guarantee oil would not still drain back when left unused. An in line valve or perhaps two, one before and one after the pump, would surely be the easist and most reliable fix.
Wasn't there a flapper in the delivery tube? If so you might just glue a peice of soft rubber to it and be done. Considering the slow rotation of the pump anything other than perfect gears and housing will probably have a hard time self-priming.
The edges of the gears should be a sharp edge or you increase slippage past the gears. I used to rebuild precision metering pumps. The gears are generally ground and lapped with the gear plate (middle plate) in a 3 plate setup. This is to ensure the gears seal against the top and bottom of the cavity. That is why you also need to keep the gear tooth edges sharp to prevent a leak path. You should not have broken the edge on the housing either. That also creates a leak path. Yours just does flow so some slippage might not matter, but will make it lose its prime easier.
As for the clearance between the gears and the walls, they should ideally be within a ten thousands of an inch or so.
Gear pumps do not self prime either fyi. If it is losing its prime, then it is probably the check valve. Wipers would probably mess with the meshing on the gears. You could make a spring loaded shoe to ride on the gear teeth at the outlet side. Think a v shape that is curved to match the OD of the gear. This is used as a wear compensator on commercial gear pumps already for transferring fluids without lubricating properties such as water. You only need to seal the last few teeth (maybe a quadrant or so), the rest are not important.
Agreed. Back in the 70's I worked with a millwright/mechanic who re-machined oil pumps for obsolete antique engines as a side line. Watching him sit and hand lap those parts always fascinated me with the precision that was required.
I agree with your comment except this is not a hydraulic pump this is a COOLANT pump that needs to handle particles of metal. It needs those 0.025" clearances to keep from jamming on the junk suspended in the oil it must pump. It all has to do with the time it takes for the particles to fall out of suspension. Junk under 0.02" may not drop before it is re-circulated. Steve's 0.005" clearance is too close, particles that small WILL NOT drop and WILL be circulated by the pump.
The edge beveling is a real problem. The edges should have been left sharp! The slope on the edges will funnel larger metal chips between the gears and face of the case. This could cause the gears to jam or bind.
Video part 3... regrind the gears to remove about 0.010" from each side of the gears to open the gap and get a sharp edge again.
@@chuckinwyoming8526 if you are getting particles large enough to need .025 wall clearance than they will bind the pump where the teeth mesh. Proper screening to filter them out will prevent this anyway. The clearance also makes it more likely to get junk in between the gears and the walls. No matter what, a gear pump is one of the worst types of pumps to use in this application. They are for precise metered flow or for high pressure applicarions. A flexible impellar pump is really what should be used.
@@anonymic79, I could pull the pump out of my machine and measure the clearances. As I recall they were very large. I suspect much of the 0.025" tooth clearance Steve measured was original to the pump. My 2HL is a direct predecessor to Steve's mill with many similar parts and design.
Unless you have run a K&T mill and had the wondrous fun cleaned all the crap out of the sump you don't have a feeling for just how much fine metal chips the coolant carries back into the sump. On my mill the drain tube from the table returns 8" from the pump sump (possibly baffled into a much longer path or diverted to the brass screens) .
I agree with you how a gear pump SHOULD be built and it's tight clearances. That doesn't apply here with very low pressure output of thick sulferized cutting oil full of metal particles.
NerdByDesign makes a great point that a gear pump is a poor choice for a dirty coolant pump.
Stainless steel sleeve to decrease gear side clearance
Put a non-return valve on the suction side of the pump, so it’s always primed
You got it, also known as a pump foot valve.
Just what I was going to suggest....
I'm thinking here that there are too many solids suspended in the oil to allow the seats to seal properly. Might work initially but will fail in time.
@@peterhaan9068 Should be OK with a soft seat and a weak preload spring
@@peterhaan9068 A finer screen should help with that, you just can't go too fine or it will clog too easily, though filtering the return oil could reduce any clogging but I don't know if that would be easy to do on this machine.
When Steve pressed out that shaft and it went "BONG!" before sliding out, I was reminded of a Vintage Machinery.ORG video where Mr. Rucker had to push out a very stubborn shaft from an old pulley center and he had to do all sorts of things to finally get it out; it did more than just go "BONG!", though, it went "WHAM!" several times, in a way that was scary. It was somewhat amazing...
Steve “Fix absolutely everything“ Summers
Cheers from France 🇫🇷
Definitely my favorite engineering channel. You have the most agreeable manner. Thanks for sharing.
Thanks for sharing your progress. My thought is mill a narrow slot for a teflon blade in each tooth.
Can't wait to see your solution. Keep up the good work!
Think a minute about a well pump. They have to have a foot valve to maintain the prime. So, you are a machinist, make a foot valve using a ball bearing, a very light spring and a really great seat that all will fit in the pickup! Come on, you can do it! Greg
I think it was a complete success, thats plenty of flow for milling operations. Well done
Steve, that was an excellent job of describing the problem, explaining what you planned to do to try to make it better, and then clearly recording the work and testing of the fits and of how it pumps. Everything was clear to see, easy to understand your plan, and what results you might expect from the work you did. You have set a new higher standard with this video. Everything was done as close to your plan as might be expected, and without showing off, just getting it done while teaching your audience what exactly you were doing and why. I hope many other You Tubers out there will study this video and improve the execution of their own work, and the videos that explain it all to the watchers. Thank you!
You sure have a lot of experts giving you good suggestions. As a non-expert I vote for the check valve and/or resleeve the pump housing. Great job so far
Great video as always. Good to see that you keep it real with the outcomes as they happen. Keep the video's coming!!!
Nice job Steve. Using a feeler to get close on your surface grinder is a fool proof method that works.....but try this. Put a white card on the left end of the table wall. Bend over and look at the white card from behind the wheel. Bring the wheel down until the white goes away. Been doing it that way since an old toolmaker showed me. When the white card become dirty just change it. Keep up the good work!
Steve, I absolutely love the detail and footage of this video series. Also, how cool is that of having a viewer send you that parts washer?! You have such a great viewership. Keep the videos coming. Take care.
Your usual top $ job keep the vids coming to the cold wet uk. Thanks
Gday Steve, I know this has been mentioned but put a check valve in line and I believe the issue will fixed, great video mate, ATB matty🇦🇺
I really enjoy your presentation of the subject at hand.
Keep on making more for sure.
Steve...
Load up the inside side walls of that pump with solder...
Get it so the gears will drop back in then reassemble it and bench run it dry with a Leccy drill....
Them gears will profile & gap the walls perfect...
Strip...
Deep clean & inspect...
Reassemble...
Enjoy good flow rates...🇬🇧🙂
Man, that is radical!
Handy tip for pressing pulleys or gears onto a shaft is to machine the shaft a few thousands ( the amount of the interference plus one ) smaller and about 0.020 wide so what you are pressing on shelf aligns. I learned that from a wise machinist who builds aircraft landing gear. He also taught me that taking off is optional but landing is not. 🤔
Thank you for the excellent videos Steve, please keep them coming. Like suggested below, I would consider a liner of some sort in the pump housing around the gears, or if you're dead set on adapting the gears, build the tooth edge up with your tig welder. Perhaps less heat that brazing, but the tooth would probably harder than ever.
Really enjoiying the repair. I'd like to see the housing to gear clearance tightened up but I agree with most about putting in a check valve. Keep the repair content coming!
In the Navy we used oil paper gasket material for those pump flanges, but when we didn't have that we just used regular paper cut to shape.
As a FYI for your parts washer I have used Varsol with several gallons of water for years. The idea of adding water is to serve as a crud trap and it also save you on buying as much Varsol, just make sure your pickup is a couple inches above the water in the tank. A buddy of mine uses a #10 can as a sump for the pickup but while our machines both started off as the same brand machine years ago they both have been modified as well over the years. I also have a second smaller capacity parts washer that I use on parts after I finish scrubbing them clean in the “dirty” parts washer, that for a number of years has been an old kitchen sink I built a stand for that 5 gal can that served as a drain and a 5 gallon rigid aluminum fuel tank that I installed a couple of 3/8” fittings in one has a pressure regulator on it so I can pump a couple of pounds of shop air to it via a hose and a ball valve the second has a check valve in case something happens and more than 5 PSI is pumped into the tank and the third has a ball valve that hose and simple nozzle end on it to rinse the parts with the clean solvent. When the stuff in the dirty washer gets to trashed out to use it becomes starter fuel to burn brush etc, the slightly dirty stuff from the clean parts washer is used to fill the dirty parts washer after it gets a good cleaning and the cycle begins all over. I tried several water based parts washer fluids and even have a table top one with the stuff in it but regardless of what the manufacturers I have found flash rust to be a problem. I use the water based one to clean anodized, blued, coated, or non metallic parts in but keep raw metal parts of any sort generally away from them. Maybe there are better water based parts washer fluids than the ones I tried so far.
The best thing about a parts washer in the shop is how much less “Gum-Cutter” and Brake-Kleen that you use in the shop and besides being expensive most people don’t realize just how nasty both of those chemicals can be on your repository and circulatory systems.
Perfect job for your shaper Steve, slotting the ends of the gear teeth using an indexer, for an interference fit of soft metal as a wiper. Copper? Brass? Bronze? Or some kind of poly type material. Enjoying this project. If nothing comes, then its a great learning experience. Thank you.
Maybe try re-sleve the pump housing... seems like the less tedious way to reduce the wear
That's what I was thinking.
Yes, make a sleeve to take up the excessive clearance.
Re-sleeving twin overlapping cylindrical cavities would be a complete bitch! How would you even go about creating such a part, assuming you knew in advance the correct dimensions and required tolerances (which we don't)?
@@afriedli a strip of shim stock, curved into the outline of the 8 shape. Wouldn't even need to close both middles. Could probably even adhere it to the walls with loctite
I think that putting in bronze sleeves would be the best. Way easier than focusing on the teeth. Yes a lot of indexing but basically boring bar work.
A new housing... from scratch! Now there's a project. 😆
Slot the gears and add whatever material works the best. Enjoyed your work very much, you have talent indeed.
Hey Steve, just try putting a ball valve as low as possible in the system above the pump and use that for your cut-off when you shut down. Keep the valve at point of use for actively regulating flow. You'll trap probably several ounces of oil up top and that should be enough to prime the pump when you start up. Start her up and open both valves and I'll bet a dollar you'll get oil pumping. Worth a try, really cheap.
Hi Steve!
Great video, as always! Watching this series I cannot help but think 'somewhere' there was supposed to be a check valve on the intake side of the pump. Think of the old farm shallow well pumps that required a "foot valve" on the end of the intake pipe. That said, a 'possible' (maybe not 'feasible') work-around. My grandfather had an issue with a seepage leak on the foot valve of a stock watering well pump, back in about 1960. He came up with a small, manually operated, secondary pump that dumped some water back down the outlet to regain prime, when he needed to run the pump. This worked until he was able to hire someone to come and 'fix' the foot valve. As said, maybe not feasible.
Thinking about the foot valve scenario, it occurred to me that (at one time) there may have been a very simple one that was inside the intake pipe above the screen. It might have been a lightweight (rubber?) ball that simply settled onto a step or o-ring seat inside the intake pipe. Possibly eroded away, or lost at some long past 'rebuild' of the pump??? Does this sound probable?
Replacing the bypass spring looks to be a very reasonable thing. However, this also sets the overall system pressure capacity, as you alluded to. IF you want 'just a little more' pressure, place shim washers behind the spring to step up the pressure, marginally. Perhaps as thick as one or two spring wire diameters? Just do NOT over-compress the spring beyond (shorter) than about 75% ~ 80% of its free space distance between coils. Many springs will begin to 'take a set' in this area of compression.
Anyway, Best regards, & God Bless!
Ken
Something I noticed while you were putting the pressure pipe back on, (where the check valve goes), is a recess or an O-ring groove for the check valve to seat? Is there any way you can check to see if the check valve is even seating properly? My guess is that all you need to do to get the pump from loosing its prime is to just fix the check valve that is already there.
Great work Steve. Keep the videos coming.
Is that check valve on the proper port of the pump? Steve is *removing* the valve to manually prime the pump (Part1 ua-cam.com/video/TDxYFJvN3Ow/v-deo.html )
I also noticed that air seems to be getting into the oil when running it after priming the pump and taking the nozzle off. (31:38). See how milky it looks? Hear the popping sounds?
On the drive side of the pump, where the shaft goes threw the top plate, is there any kind of a seal on the shaft? If not, this may be where it is pulling air in when running and allowing air in when not running and allowing the oil to leak back into the sump.
I also think Dennis Williams has a great idea, raise the oil level in the sump may help.
I think you are all onto the problem with this pump. The check valve above the pump keeps or slows the drain-back above the pump. Ideally, there should be a (light)spring loaded check between the pickup foot and the pump body. That would keep fluid in the pump body above the sump level. Maybe there was one there at one time and it just got replaced by the pipe nipple.
@@ramosel The "spring" that forces the check valve to close is the 30 inch column of oil in the riser pipe above the check valve (and the weight of the heavy brass flapper itself). That should be more than enough to force the flapper in the valve closed when the pump stops. It works the same as the flapper in a toilet tank (which has less than 8 inches of water closing its flapper).
All the discussion about pump clearances is irrelevant. He only needs to make certain the flapper can form a good seal, AND he needs to ensure there aren't any leaks (in the pump case or the pickup tube) which would break the suction when the pump stops.
That sound right to me. Also I am thinking that "This Young Steve" is on to it too because he was rather insistent that we watch Part 1. That's fair, if he has some fun at our expense. We get plenty of enjoyment from his tireless endeavors.
Great video and thank for the guy who send you the part cleaner, the next thing to make live easy is a sandblaster so you can clean part from paint, as always thump upp :-)
I like the idea of slotting the teeth (like an eccentric vane air horn pump). Guaranteeing that one won't go squiffy at some point and jam up the works will be a challenge. Jet engine vanes have a complicated "slot" in the hub, but obviously turn at slightly higher rpm than your oil pump. Good Luck 😃, love your videos.
WOOHOO, , , Saturday with Steve. Looking great bud. I did a bush fix on one of these pumps once with various sand papers and an old mirror. It took me almost 2 weeks to do but as far as I know it is still in service 6 years later. Great refit my friend and what a great gift in that washer. You have some fine friends bud. 900 likes is really impressive Steve. Well done fella. I am on your side with doing the inserts. Poss some hard brass liners as well. OR you can just make a primer reservoir for the pump to give it a shot to get it going. Seems it will hold a prime for a bit eh.
Air in the pump body compresses and decompresses unlike the oil that it is meant to pump. Either increase the oil sump level to reduce the suction needed to prime and/or install an effective check valve just below the pump. The pump itself is working as designed, good job on the rebuild.
Excellent work dear friend
very good with simple equipments !
That initial POP is always a shock. SQUIRREL! That is my favorite Dremel cut-off wheel, too. I hate the new ones with the twist lock arbor. That was some great work to rebuild the pump, too bad it didn't work better. I have no experience rebuilding pumps, so my first thought was a good check valve in the suction foot. Good luck, and looking forward to seeing what ever you do.
Great watching your videos Steve. To fix the pump you could decrease the diameter of the pump housing walls. I don't recall what your gap is but I would take some precision shim stock and trim it to fit then use some green loctite to stick it to the walls of the housing. Probably need to turn a couple of short bars to clamp it in place while the green loctite sets up. I have some xtra shim stock coming your way shortly.
Steve somehow put in a check valve in the pickup to keep the coolant from draining back into the sump. (simple one would be a ballbearing and spring) Or a flapper valve from a plumbing supply
Good Video so far Steve, Next step I would take is to build up the cast housing some how maybe by brazing and re machining. Over sized gears are out because of fix shaft locations. Gear tooth clearance is letting oil drain back while off. Could also make a new housing out of aluminum . It will wear but not too fast. Seen a lot of hydraulic pump in equipment with aluminum housing last years with metal particulates being pump through.
As someone else mentioned, use JB-WELD to build thickness on the side wall of the pump body. Set it up and resurface the bores with a few tenths clearance. I did a spool from a 16 head filling machine to better fit the valve body, worked great. I used the one with metal in it. It cures hard and is good to machine. Also mentioned is a check valve. Good luck. George
Order yourself the Dremel EZ Lock cut off wheel kit. It's expensive but you will never go back. The wheels last surprisingly long. The cutter is driven but floats on the end of the mandrel so if you bind it in a kerf, there is no blow up. It will just run off axis and keep cutting.
Great content on machining and precision measuring. All I have for an easy suggestion has already been made, a check valve in the pick up tube if one will fit. Unless you can find original dimensions for the gears to see if they are the problem or if it is the case. Anyway, keep up the great videos.
Tell that guy on your shirt to get back into the swing of things!!
Thanks for the upload Mr. Summers
great vid, my vote is for the NRV also. At a pinch you could bond PTFE liners into the bores and rebore, but that sounds like a pain and you will probably end up with something that will still not self prime.
This is a very good episode in the continued saga of Revival of Old Betsy.
I think a synthetic/polymer vanes are a good idea. A complex machining effort perhaps. A better idea would be a pair of sleeves in the bore.
Just remember, the gears may not touch the cavity walls but something wore out the cavity.
Nice job on the pump. Is there a check valve between the pick up and the pump? If not, that might help maintain the prime.
As for the solvent tank, used that same model for over 30 years. Still on the original pump and it's used daily. As for solvent, low odor mineral spirits works pretty well.. Expensive through Home Depot or Lowes. Might be cheaper through a Petroleum Wholesaler in bulk. It doesn't turn stinky here in the southwest heat which is a big plus. In addition, adding a screw-on diesel fuel filter between the pump and the brush hose extends both the life and quality of the solvent.
I would make sure the check valve is sealing first before I did anything else. Like your channel keep it up.
Steve Summers, really enjoying the channel, love how you represent fellow UA-camrs by wearing their shirts, so where’s the Steven summers shirt? Maybe one with a Avatar of you and your wife, huh maybe. Keep up the Quality content!!!
Morning Steve! You made some big improvements, I'm impressed. Before you do anything to those gears, look into the Plastic Steel I was talking about last week. Kind of expensive but would be an easier repair.
Great job Steve.. Lots of good comments here.
Learned a lot from this video and the excellent comments below. Thanks Steve and all commenters.
My K&T self primes no problem, I also worked with loads of gear pumps in the petroleum industry, try adding the check on the suction side and yes the rotor tip clearance is too big, add some tig bronze on the teeth and get the fit as tight as possible.
That surfacing machine really grinds my gears... :)
Hi Steve you could slot the ends of the gear teeth and insert a floating graphite piece that would push out with the centrifugal force and press up against the sides of the body. this will ensure virtually zero gap between the teeth and the housing. this is how the scavenge fuel pump on aircraft work. just a thought. Thanks for the great videos and interesting content.
I agree with some of the previous comments on the check valve. Maybe you should work on the existing check valve and see what the problem is with it. They probably put it there for exactly that reason. If it seals than the pump wont loose its prime and your good to go.
Looking at Part 1, It appears the brass flapper would block any reverse flow that might prime the pump. A check valve on the input side and a drive shaft seal if necessary would allow removal of the brass flapper.
Use a sleeve.
Bore out some of the cast iron material from the pump housing and then insert a sleeve ( of course you have to cut some of the sleeve material a way for the inlet and outlet area ), but this would tighten the area around the sides of the teeth allowing your pump to build more vacuum.
I ran a PSI screw supercharger on my alcohol dragster. I sent a BRAND NEW PSI & had it epoxy coated in the hsg. & the screws; they then "run it in" with lubrication, (just like lapping) & it improves the screw's performance about 10%. Epoxy spray your housing & gears, then run in the pump with some lube. You'll be amazed.
I agree with Dennis Williams. If you can, raise the oil level in the sump. This will create net positive suction head. The pump will then self prime.
Excellent mini series Steve. I wonder if it's possible to bore it out and make 2 partial sleeves. It'd be an interesting job considering the figure eight shape.
enjoyed as always
Steve: My rule has always been "don't scream til you get hit". You have taken a lot of the slop out of the pump and it basically worked before. Put it back together and see if the improvement is enough. If not, you might be able to get the gears hard chromed.
Good luck!
Raise the oil level in the sump up to the gear pump. If the cutting oil is up on the pump it will self prime then
LOL
that is the ticket :) just keep the pump fully submerged.
Keeping a simple gear pump submerged in the oil has been done for ages, it's simple and it works. Really enjoy your channel, keep up the good work.
Your notion of slotting the teeth was my first thought. But I think the inserts will interfere where the gears mesh. You could use flat brass shim stock, bent around the gear bore. It could be made to stay in place by bending the ends and drilling corresponding holes/slots to retain the ends. Good luck Steve.
I watched part 1 This Old Steve!
Did you see a brass flapper valve in Part 1? What is that for?
Good job, Steve. You might try coating the top of the pick up tube with epoxy after a very through cleaning.
Silver solder to build up the gear teeth. It is reasonably hard and low temp and easy to do. Won't affect the temper. You could also use it to fill the ruts in the housing but it would be trick to bore it flush. Minimum investment in time/money. No guarantee, but I think you always start with the easiest method. Good luck whatever you do. Oil pumps in aircraft engines are exactly the same so I am watching this with interest.
I get my solvent from tractor supply and I mounted a large fuel filter on the side of of the tank and ran my solvent thru it , works great
Steve, I had lots of fun working on my 1942 K&T 2HL and getting it running again. I suppose that is why I enjoy watching these videos. Mine was in much worse condition than yours when I re-built it.
I installed a T in the coolant outlet pipe at the top of the casting with a second valve, an elbow and short section of vertical pipe, open at the top that I can fill with coolant to prime the pump. You may want an easily removable dust cap on the pipe.
As you commented on in the video the coolant pump must be able to handle some trash. This is NOT a clean hydraulic system and you don't have any filter to remove small particles. I questioned if your 0.005" clearances on the gear face is too close. Particles that small will stay in suspension in the coolant for a long time. How viscus is the coolant you are using and was this pump designed for really thick sulferised oil?
Today we want to push a button and have everything running. That is not how these machines were designed. They require an operator to setup, startup and keep them running.
Steve I enjoy the videos. Looks like a "foot valve" would fix the priming problem.
Not many oil pumps will pick up dry. It's only for moving coolant after all, so if it works let it wear itself out by using it. Keep up the good work.
Steve, sigh I had my fingers crossed. Epoxy coat the walls and then machine to size. There are epoxies formulated for fuel tanks,.etc. Less expensive than plating as someone else mentioned although I'm preferential to plating.
always enjoy your vids... all the best from Ohio. My suggestion is to make two "bushings", press them into the pump (making new housing walls to mesh the gears).. just cut the extra radius off the gears, maybe attach them together somehow (low/no heat)... seems a better fix than to work on each gear tooth seperate
try a nonreturn valve on the lift pipe to stop runback Steve.
Steve, I would begin by boring out the case as much as possible. I'd then bond in some Turcite (or similar material) and machine it to achieve the desired clearance with the gears.
Steve....I like your idea of slitting the ends of the gear teeth and inserting Teflon 'wipers' to increase the pressure. I say Teflon because it's flexible enough to be set to 'wipe' the inside of the pump housing without permanently deforming.....and increasing the likelihood of maximum pressure. Honing, or even re-boring, the interior surfaces would probably help, too, and the 'wiper' solution would adapt best to that, I think. Really enjoying your videos. Thanks! :-)
nice working
Very interesting Steve,as always thanks. Uk stan
If you took out the check valve and put a longer “head” above the ball valve; as when it is running with fluid, you shut the ball valve off, the line will hold fluid so when you want to use it again, open the ball valve and the fluid left in the line above the pump will drain back, priming the pump. That would be an easy fix without fixing anything.
If you can spray weld, I think you could can mask, weld, and then turn the gears. Here's something interesting. Vintage Norton and BSA motorcycles use an oil pump like that just much smaller. They have the opposite problem. The oil tank is above the pump so the pump is never dry, but oil leaks past the gears when the engine is not running, filling the crankcases over time. When that gets bad, we lap the covers to remove any wear and the body to reduce the clearance to nearly zero - want as little clearance there are possible without binding.
With your kit and skills I'd bore and sleeve the housing. Loving the videos, hope the Banana skin trick worked with ripening your Tomatoes
Hello Steve, As a Pro machinist in a Hydraulic design and repair shop for 30 years I've a little advice, No1, check valve after the pump and before the pump will keep it wet, simple Gravity biased Marble design will work. No2 if you want to fix the tooth clearance issue simply machine off the housing altogether so you end up with a bearing plate and the use a block of Ally, and bore two holes of the correct diameter to match the gears you have, you then make alignment plugs to align the bearings to the new housing and fit dowel pins it's 6-8hours work and will be as good as new, done hundreds of these.
All the best
Rick
Nickle plate the housing and gears then machine for clearance (make sure gear teeth and chamber walls have uniform wear or re-machine before plating).
Would plating be thick enough?
@@googleuser859 Nickel & nickel chromium is applied in "d" layers of about 0.0005".
I would blueprint the existing housing, and then fabricate an entirely new housing from a block of material.
But then I'm the type of person who enjoys such a lengthy process, as well as the satisfaction it brings. 👍🏼
To reuse the setup you have I'd OD grind the gears and make a new gear case from a block of cast iron. My initial thought upon watching part 1 was to come up with a way to retrofit a Ford gerotor style oil pump to the unit.
Growing up in WVA... that jug of Way oil looks very much like another type of Jug that I have seen :)
Hi Steve! I really like your videos!!
As the wear should be relatively even on the gears you could turn the inside diameter of the housing to accept a brass bushing wich you could again turn down to fit with the gears. I also think that five thousands of an inch is way too much of clearance between the planes of the gears and the top of the housing. We worked on a gear pump that had tolerances of +0.03mm so about one Thousand of an inch between gears and housing.
Greetings from Germany!!
Hope you’ll get the pump to work!!!
Make a non-return valve from a bit of plastic, ally or brass and a ball bearing. If that doesn't work then build up the teeth with braze and reprofile. Great videos. Thanks. Mike
I was gonna say sleeve the pump, but it’s been said - my add on idea, is make the sleeves out of brass. Also, probably a good idea to make that pickup screen a little finer, keep some garbage out :-)
Probably the best fix will be to make a blanking plug for the idler gear, and get a rubber impellor to replace the drive gear. Looks about the right size for a common boat coolant pump gear, and as those do flex, it will both self prime and also handle solid bits fine, plus bore wear is not too much of a problem. You might have to change coolant to a different type, or get an oil resistant gear, but that will be both cheap, easy to do and reliable, just order impellors in batches of 5, as they do fail with little warning other than the rubber flake count rising rapidly. You could even buy genuine parts ( Evinrude, Yamaha, Mercury) or one of the multitude of aftermarket parts. You even get those pump impellors in dairy applications, where they need to handle fat without issue, so are made from a variety of synthetic rubbers as well.
How about drilling two holes in the tip of the gear and use two dowels (tapping those gears might be difficult) and pin a strip of brass to the outer edge? maybe do some kind of fancy reverse chamfer on the end of the dowels to help hold the brass, maybe just a touch of sealant between them just to take up the gap. No heating required, then turn them down to get them perfectly circular.
Hi Steve got the same mill as you my pump would never pick up dry but if you prime it it would and run all day and the next day to,once primed.i think it’s your little flap none return valve letting by.the pump should have oil in it at all times
Hi Steve I'd feeler gage tooth gap and if it is similar tooth case clearance then i'd get the gears hard chrome plated on the teeth area and OD of gears, if the tooth clearance is equal to case gap.
foot valve might help and a primer hand pump.
Nice solvent tank.
Hi steve ...I would weld the gear tips ....then chuck it up in the 6 jaw lathe chuck center drill the one end of gear ....turn diameter to .025 thou. Needed for zero clearance from the feeler gauge / straight edge gap...hand grind or mill off access weld maybe blue mating gears ...( like blueing in rack and pinion 4 wheel drive gears lol)( don’t touch grounded lathe gear tips ) easy peezy
JB Weld or a similar metallic epoxy putty might be worth a try as an alternative to brazing the tips of gear teeth. Easy to machine a close fitting OD and easy hand finishing the profiles of the gear teeth.
a ceramic rod... I have never seen that before. Nice
I like the idea of wipers on the tops of the gears just because it’d be cool 😎
Awesome! Been waiting for this. :-)
a good check valve on the pick-up side of the pump would be the best, or if you dont want to change the original set up, then re-sleeve the case. just be sure you have fun doing it!
Grind that pump case down to reduce that .0055 down to about .0015. Touch the gears back and leave the edges sharp, same with the case. Get rid of the screened pickup and put a ball check on the end of the suction tube. That is what I would do next.