BORING BRIGGS AND STRATTON QUANTUM ENGINE ON BRIDGEPORT MILLER
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- Опубліковано 2 жов 2024
- Boring out well worn Briggs and Stratton .020 on a Bridgeport milling machine. There is a second video of assembly and the motor start up. • BRIGGS AND STRATON OVE...
I've been a machinist for 25+yrs. You just mount a dial indicator in the Quill and rotate it around the hole you are trying to center. When the indicator reads the same on three points, two of which are diametrically opposed, you have center. This was done at my place of employment after hours. Took about 1 hour from initial set up to finished product. The problem with owning a Bridgeport is the cost of the necessary support tooling. Without the tooling U just have a really nice drill press.-TM
Hey i have a race mower that i have i have a bigger jet on the carb than stock i got after market valve springs for it do you think bore it out to get a bit more out of it because its a 17.5 hp engine running a 22hp jet from another mower?
Don’t listen to all the bs ppl are saying. They’ve probably never tore an engine down before, let alone machine one. As a hobby machinist, I enjoyed your video very much. Thank you for creating it
Sticks and stones-Thanks for your nice comments.
I have a B&S tiller motor, with aux shaft. The cylinder is badly scored. What should I expect to pay a Bridgeport operator for a bore and ring fitting?
Very good presentation. Although I do not get into this type of work, I do however
comming up, to do a V8 flathead. The challange is holding. My thought is to
turn a round fitted to the three main bearings (with the old main inserts stil in there)
Customer only needs .010 over. I know its been done on a mill (but not me)
so what do you think. Oh the reason for the bar through the mains is Cincy heads
dont nod like Bridgeports or it would be a snap.
You can't please all the people all the time. I glad that most people enjoy it.-TM
Congratulations! You re machined a B&S engine to tolerances of at least 10 - 20x those the actual factory ever used on a good day! 😎
Owned a out door power equipment company for over 20 years. Back in the day when the engines were not throw away. We used a stunned honeing system to oversized cylinders. It was more accurate and much quicker. .010 oversize in 10 min including set up. Boring those aluminum cylinders there is a chance to cold weld material on the cutter and be oversize on part of the cylinder. That on some cases made them junk. Aluminum bore cylinders have a chrome plated piston. Cast cylinders use high silicone alloy pistons.
Silicon & silicone are two very different things…
hi how much does it cost to bore a cylinder on a machine shop??
I overbored such engines with aluminum cylinders and I've been never lucky with them , there is a plating similar to nikasil on those cylinders and when destroying this plating, new rings have a tendancy to scratch the new cylinder
I had better results when I could install a cast iron sleeves
i didnt find this out till it happened
5HP B&S cylinders are not coated. Hell they don't even use crank or rod bearings.
Nikasil and all cylinder plating can be refinished and bore restored. It's standard in the motocross world.
Good video. Meticulous machinist. However, I would have used a torque plate. It gives a more accurate bore shape and size, as it would be with the head torqued down. Even hone with it. Maybe unnecessary for lawn mower but you may get another 100,000 miles out of em! ha. Easy enough to make out of thick aluminum.
C'mon, it's a used lawnmower engine! It will never be installed in a top fuel car.
Nice video! I own a really old B&S 3 hp engine, which is made in 1981. It has a aluminium cylinder, a badly worn one. I'm really considering about rebuilding the engine completely but the fact that it has a aluminium cylinder wories me. If I choose to bore it and buy a oversized piston, is it possible to make the engine last long? Does anyone know if there are B&S engines, which have iron cylinders?
Thanks for the nice comments. The industrial grade (IC) engines have cast iron cylinders as well as many of the old engines. The engine in the video was an aluminum bore. You can bore the 3 hp and make it work but quite honestly I did this as something to do and I am not sure I'd put the effort and expense int a 3 hp.-TM
Good work, I just got a full size mill and I'm thinking of doing stuff like this if necessary. I have a 2 cylinder scrapped block I just might practice on. Set Up could get tricky.
At the price of taking a block into a machine shop and the crap quality of most engines now days,its best just to buy a new engine. I have actually bought new lawn mowers just for the motor as its cheaper sometimes. I did that on a horizontal mount rotor tiller that used a typical mower engine. The original was trash and it was cheaper buting a cheapo mower and using the motor. Seemed weird scrapping a brand new mower chassis but I sold the tiller and that paid for the mower twice over.
this video is not boring
+valdarmort Unlike me who is!
Me too, but I enjoyed the experience
I find it much eaiser to bore them on a lathe on a face plate.and clamps much more ridige
Build a torque plate and torque to factory specs to start with! This will straighten the bore before the first cut! Then finish shy of bore size with the plate installed and then clean it up honing to size! By doing it this way you are loading the bore with the torque plate and you should end up with a perfect bore?
Mike Mansfield it’s not a friggin race motor, this thing would never know the difference.
Thanks, I ended up doing two motors of the same type. Both ran very nicely. I'm fortunate to be able to use some nice equipment.-TM
Could you do a video of the honing and the chamfer? Thanks. Great video. Also more on the setup and getting it level
Enjoyed watching. Got a little motion sickness with the way the camera was moving around lol. But no big deal. Thanks for thinking the time to share. GW
The tool bit was an old lathe bit which I brazed a new carbide end.The tool shank is round but has flats cut on each side. It is secured into the boring head with a set screw. It is important to have a corner radius on the bit about .03 to insure good surface finish on aluminum. I used WD-40 as a cutting fluid I bent the tool with an oxy-acetylene torch to get the cutting tip past the boring head body. Any ready made bit will work if it clears the boring head.
Yes. I HAVE seen those "dingle berry" hones before.
This was a standard process on small engines in the 70´s. Then the stupid society started to throw everything away and "replaced".
Couldn't have said it better myself! These morons these days love giving their money to china for cheap junk replacement parts instead of paying a American hard working neighbor to recondition a quality OEM part! I work in the small engine repair/ Performance Mod field myself and know it first hand. The loyalty to each other and this country is almost completely gone more and more with each new generation.
@@cycletechperformance9581 It´s sad, but true. Here in Germany, things are about just as bad. The only thing that you and I can still do is being an example to others and do it better. Even if that doesn´t change things largely, at least we fiew can say that we haven´t sold ourselves.
@@v-g-z3689 Cheers to you my friend! We keep doing what we do as long as we can.
@@cycletechperformance9581 Quite right!
Fantastic video. I need to bore the same engine Would you please give some more details about how you made the boring bit. Most importantly, the square peg in the round hole. I can figure out how to tilt the bit, once I understand how you managed to secure it firmly.
How you made the cutting tool, would be another great video.
Thanks for a great video. I have a small milling machine and wondered how boring a cylinder went. This was exactly what I hoped to find. I like your common sense approach and honest comments. Well done.
seems like you should have gone 10" over. cost you a full rebuild by going bigger!
The commonly available piston for this motor is .020. I couldn't be sure it would clean up at .010. The motor will outlast me anyway.
Good video on boring out a cylinder I enjoyed watching !!!!
Hi Thanks for your interest. I used a chamfering tool that is a hand held pivoting scraper that does a real nice job of deburring pipe ID or any holes. It allows a very controlled cut. It ends up being about a 45 degree chanfer, just enough to allow the rings to easily start down the bore without nicking the rings or catching on the cylinder bore. Search hand deburring tool on the web, Noga is a common manufacturer.
a lot of know it all here ! Keep up the good work Love to see people using their brains not their mouths.
I guess negative comments make some people feel important. It's fun to see how low they will go. You can't fix stupid. Thanks for your considerate comments!
Have you got a Video of a 3.5 Hp ! Boring the worn Aluminium Bore Out !! To insert a Cast I Iron one in !??
A fascinating video, with some sensible comments too!
+g0fvt -Thanks for your nice comments-TM
I remember watching my Dad boring out the air cooled blocks and he would get 4/5 ready and then start
It was fun learning how to do it 😊😊😊
I tried my 5hp briggs on the mill it was close so i chose lathe but you did a fine job there.
Thanks for the comments-TM
Wow! Thats awesome actually doing a professional job on a Briggs and Stratton engine rebuild! This is how its done properly, not just slap a set of rings on the engine. When mine comes up for rebuild i'll be taking it to a machine shop to make sure the job is done just like here.
Thanks for your nice comments
Nice job! Is the bore of a B&S plated from the factory, or do the piston rings ride right on bare aluminum?
I think there was both situations depending on the model. I have bored several of these engines and they all have performed well after the rebuild. Thanks for your comment
Yes, it was an old tool I put a bend in to work in the small bore with the boring head. I think I brazed the carbide bit to it. It's important to be sure to have a .020 or so radius on the cutting tip to get a good surface finish.
Great video, I like your setup!
Is it ever practical, with the time and effort to bore out a cylinder, to go with a sleeve?
+Larry B Depending on the engine and it's rarity or necessity to rebuild it, installing a sleeve is not much more work. For an engine like this one, It's more practical to just get a new short block or a good used one. I only did this because I could. I'd never consider paying someone to do this type of work in this engine! Thanks for your comments!
I can't do this line of work cause I day dream and fall asleep too much.
Outstanding video---clear, concise, and informative! And what a beautiful shop too! A few questions, if you don't mind:
1. Did you chamfer it with the boring bar while to had your center, or use a different tool?
2. Assuming one doesn't have the equipment or the expertise, does an automotive machine shop usually provide this service?
3. I'm currently rebuilding the engine in my kid's go kart, and I'm finding between the cost of parts and (possibly) machining, I could buy a more powerful "Predator" engine from Harbor Freight for cheap. Do you have an opinion on these cheap engines?
Again, you video was terrific, and I thank you for posting!
Thanks for your nice comments. I used a hand held chamfering tool to do the chamfer. It's just to break the edge to facilitate piston /ring installation. I doubt an auto machine shop would do this. Quite honestly, unless you can do it yourself its probably more cost effective to just replace the motor unless it is a high end motor i.e. a large displacement/multi-cylinder commercial motor.
tmackinator Thanks for the reply. I just tore down the engine a few hours ago. It's a 3-1/2 HP vertical shaft Briggs from a vintage "Coca-Cola" Model T go-kart that was a promotional item back in the 80's, so it's worth some bucks and I want to keep it authentic. Fortunately the cylinder and piston are in great shape, so I'm ordering standard rings and will hit the cylinder with a Mickey-Mouse glazebreaking home.
Oddly enough, I'm a bit disappointed! Your video whetted my appetite to delve into machining the block to an oversize. I wish you were my neighbor!
Hi, i know this is an ancient video, but was wondering how you honed this? In the Bridgeport manually throwing the quill lever for cross hatch? Or just a hand drill. Or maybe you have a honing machine. Enjoyed the video. I bored out a 50cc kart motor once, but had a lot of chatter. After watching your video, im guessing i was turning it too fast. You were probably turning less than 200 rpm. I think i was going 500 or more.. thanks again
I used a good quality 3 stone hone in a hand drill.
This is the correct way although zero reading is perfect always!
interesting to watch tanks for posting. However it doesn't look like this would be very practical for reconditioning small engines to extend their service life. In a time where mass production along with the war on labor has driven the price of new so low.
i got one of these engines from my local junkyard it was in kind of good shape and i already had another engine block just like it i decided to make a 2 cylinder engine im still tearing them down to see what problems im going to run into to make it a 2 cylinder
Did you succeed?
If you go Honda and change your oil.......you can go to the pool hall and drink cold BEER!
haha hell yea man lol honda engines are pretty much like the best out their i like them better than briggs anyways alot more reliable
What diameter ‘Shars’ boring head did you use one the Briggs boring ?...Gary in Michigan
i love seeing these engines
It was fun-TM
how did you get the cutter to come out of the boring head at an angle? heat and bend?
Yes it was a custom cutter to get the stickout I needed.
Useful video for go karters!
I couldnt help but notice that you were zero (flat) on your side to side of the deck of the cylinder. Why didnt you check for flat Fore and Aft? T
If you listen to the narration, I state that the block was just as good n the other direction. Rest assured I checked the set up in X and Y. It's not so easy to film narrate and machine all at once! Thanks for your interest in the video-TM
Are you doing this for a project i'd like to see this engine running!
we have a Briggs 170402 7HP that is on a 1971 Toro 726 snow thrower. What should the compression be about? I twas given to us a few years ago and it seems to me that the compression is a bit low, it does big down but once it starts to bog it hits its torque band and maintains but was just wondering if you knew the compression for an old side valve. Thanks, Joe
Typically Briggs L-heads engines are in the neighborhood of 6:1. If your motor is otherwise in good shape, you can probably eliminate the bog by careful adjustment of the main jet. The updraft carbs used on this motor can be sensitive to carb adjustment. It's best to adjust the carb with 1/2 full tank of gas. Fuel level can affect performance. I find that sometimes I have to readjust the carb slightly on a snow blower as temp and fuel level change. -TM
tmackinator
6:1 wow, thats pretty low... Then That seems about right, on a compression guage it brings just over 90 psi I think so, guess its fine then! The carb is always leaking fuel, and we have tried tuning it. Boy its not easy... Is there any way to possibly convert the motor to a regular horizontal carb? Tried tearing down the original, couldn't get it apart, might try again and order a rebuild kit but I dont know if its worth it... A new updraft is $150!!
I may make a video of a briggs with no compresson running on nitro
Wouldn't ordinary tool steel have been good enough in ally? A new short block would have been a quick way out, but then you wouldn't have got to show this video of course...just saying, good work though.
I am trying to do very similar thing when rebuilding my old outboard engine.
Could you please let me know what kind of boring bar and boring head you are using and how do yo angle mount the boring bar?
thanks!
@tmackinator I'd like to know this as well.
Great video and great set up!
Can I use drill press do it?
I am not used to seeing a boring head running anti clockwise.
Just the tool I used.
HI I have a 13 hp briggs inteck that is aluminium with a chromed bore, the piston broke and scored the cylinder so it needs a re-bore and oversize piston just like you have done..
Question, the bore was chromed, after machining it will be aly to steel rings, how long will the cylinder last ? actually i want to run this engine for a race, one afternoons worth of thrashing it's nuts off so if it only lasts 2 hrs that's enough, but the question remains as if it survives i might throw it back in a mower, I have only seen rebored steel or cast bores. what are my chances !!
If you have to pay to bore it, it may not be worth it. If you can bore it and use cast iron rings, it should easily go the race.
do you do work like this if i would send you a block and piston.
Sorry, no
A torque plate pulls the cylinder back in line? Never bore without one ever it loads the cly. Walls
Could you do a video of the honing and the chamfer? Thanks. Great video. Also more on the setup and getting it level
Hey there! I love your videos! I have never machined a engine block before but I am willing to give it a shot now. I have a quick question though... Where do I find what the bore specs are for the cylinder bore? I heard you say that "Briggs and Stratton gave you the specs for the bore" Is this in a manual? Do you get the Oversize Piston from Briggs too?
Thanks tor your comments. The bore specs for various B&S models are commonly available off the net, possibly on the Briggs web site. I printed off a spec sheet but can't remember where. It's not hard to find. Quality pistons are available from your favorite aftermarket supply house many of which have genuine Briggs parts.
It was a carbide bit I made to work with the boring head to fit the bore and give me enough depth to do the cylinder.-TM
Hi is that an aluminum block or cast iron lined.
Aluminum
Really boring
Ok, you said if I can bore to .010 do that. But, they only make a .020 oversized piston and ring set. Would I be able to use standard Size piston and rings if I only go .010? I just want the tightest fit possible
+CJSuhr You have to use rings designed for the bore. If .020 is what is available use that. The ring gap would be way to large using std rings on a .010 bore. Plus the rings would not be of the correct diameter to start and would not fit the .010 overbore correctly. Just go with the .020. It is the best way to go in your case.
+tmackinator Ok, thanks for the help!
+CJSuhr Pistons are made to have a specific clearance between the bore and piston too. This clearance is around .005 and allows for expansion due to heat so the piston doesnt seize in the cylinder. If you use a standard piston in a .010 over bore, you now have .010 extra slop in the piston which will easily gull up your cylinder walls since there is next to nothing to hold the piston true with the bore.
No "go juice"?
How I wish I had a BPT miller ...
Good video on on how to bore a B&S, if you would share what type bit are you using?
Did you drop the knee of the machine down and check the bore size with a dail bore gauge? Just wondering what you measured it with.
I used a snap bore gauge.
search this title : BRIGGS AND STRATON OVERBORE FINAL ASSEMBLY AND COLD START This is the video of the finished piece running. Thanks for your interest.-TM
Nederlandse taal
What did you use for your camera? It's great.
***** It was a hd flip cam.
Thanks for your nice comments. I've been enjoying your train vids!-TM
Easier to take more out than to put it back ;)
Круто
Спасибо!
Not a cast iron b dam
Why are you boring in reverse? It is a good way to unscrew the shank from a Criterion style boring head.
+John Reese I'm not sure where your are getting your information but except for the sliding dovetail,the boring head is one piece including the r-8 collet piece. It doesn't separate or unscrew. My tool was made to cut as you see. I've been at this for 35 years, trust me I know how to machine.
+tmackinator
OK. Mine have screw in shanks.
Agree with John Reese: the shank would likely unscrew from a Criterion head in that direction of rotation. Beautiful job nonetheless!
after boring do you have to get bigger pistons?
Yes
Not always sometimes you can use dry sleeves. I'm not sure if thats an option in this motor.
A left hand lathe bit?
What HP is it
How do you control how far you adjust that cutter? Seeing as the quill has to remain centered I'm curious as to how you can accurately do that.
Thank You.
The cutter on the boring head spins on a center line which is set on the zero position of the cylinder bore when the quill is initially centered in relation to the bore. The boring head can be adjusted to make the swing of the cutter larger or smaller in relation to the center of the swing which does not change. This is done by adjusting a threaded screw . The cutter is mounted on a sliding dovetail that the adjusting screw moves in or out to change the diameter of the cutting circle which always remains true to the center of the quill.
tmackinator
So you can simply measure how much of the cutter projects vs how much projected at the original position, and double it, to determine the difference?
Thank you!
The American Outdoorsman Well sort of. There is a graduated dial on the boring head and it is graduated in .001 increments to move the cutter in or out in the amount of material you want to remove.One full revolution of the dial is .05" If you want to take an additional .01 off the bore, you move the dial 10 graduations. This moves the cutter by .005". Some heads are not a direct read and if you want to take off .01", you move the dial 5 graduations which results in .010 being taken off the bore. These are usually crappy brand boring heads though.
tmackinator
Thank you for taking the time to explain this. Makes sense now.
Would this give it more power
In that it restores compression and efficiency, it will have more power but as an overbore, it won't make it a hot rod. It will run as well as new.
That cleaned up real nice.
Thanks for your comments. Along with everything else, a properly sharpened tool is critical to achieving a good surface finish.-TM
How and when do you do a valve job on a flat head engine?
Invest in a tripod
Why don't you buy me one and ship it to me.
how far can you bore out a lawn mower engine?
yes
It depends on the size of piston available, mostly.020
This is boring.
goddamn aluminum cylinder walls...this is boring lol
You're really supposed to have your over-sized piston ready to go so you can match the bore size and include the proper clearances.
The motors are so easy and cheap to find. I dont really fuck with'em when they get like that
Still left u a like. Boring an engine is interesting but at least around here man I thought I was gonna get nothing but quantu Briggs motors all summer.
any replacement available for my 282707? can't find any! nice to see someone is going old school and bore that thing and is able to get that a second life. sadly for me: here in germany i can't find any person/resource how just willing to do this. everyone says: get a new one! but… as i sad: there is no new/replacement for the 12HP 285707. and now? any thoughts or recommandations?
Wow this was so boring. hehe see what I did.
just remember, after boring aluminum cylinders you must re-anodize them as it is such a soft material. this is as to harden the surface, and extend the lifespan of the motor. If you don't, the motor will be burning lots of oil soon.
Why would dick with an inefficiant flat head when you could by an over head valvle briggs intek, or an overhead valve animal motor? yea maybe if this is a classic unreplaceable motor that is specifical to an application..
There are pros and cons to every single engine. Side valve engines don't have the annoying problem of the piston smashing the valve into the cylinder head when the timing fails. This is one example. Another advantage is the simplicity of design, less moving parts, less wear, better reliability and service that is cheaper.
Sure efficiency isn't the best, nor is its power, but a flat head is more rugged and likely to outlast its OHV or OHC counterpart (after you run out of engine oil). Efficiency, is just related to design and flow characteristics of the flat head engine (which cannot really be remedied in its current configuration). I have heard the OHV B&S have a problem with the head gasket getting blown apart between the cylinder and the valve assembly, leading to burnt oil and lots of smoke. Another problem flat heads don't have.
I raced a b&s animal ohv for 3 years, never had a prob with head gasket, it was a great motor, would run up to 8100 rpms and still had some left. All I had done to it was a billet rod,dual valve springs,.308 billet cam, 3 degree timing key and a big ol'e carb and she won a bunch of races.
+superkart66 id hope it would last 3 years. especially for the price. my profile pic is a similar engine in this video. it has had about 3500 hours of work and has not had a rebuild yet. starts first pull everytime. it is a side valve. i prefer side valve for sure.
I work on small engines that block is not worth the world you did
I didn't do any world
There is so much camera motion that the video is unwatchable.
Thanks ever so much for your insightful and well thought out comments.