Years ago, back in the late 80's, lots of GM 3800 v6 engines were getting enough mileage that they nerded the timing chain and gear replaced. The original cam gear was aluminum with a nylon material on it. The replacement set was all steel. What GM neglected to mention was you needed a cam button kit in addition to the gear set, and the cam button kit was sold separately. The original timing set had a cam button, made of plastic and a light spring. The upgraded set was metal with a flat roller bearing and a heavier spring, because If you tried to use the old cam button the crank would walk forward and with the new gear being thicker and heavier, the old spring couldn't hold it back, so the cam gear would walk forward and strike the cam sensor in the front cover. You could start the car one time after finishing the timing gear set change, but if you shut it off it would not restart. It required tearing the front cover back off, and replacing the magnetic pellet on the gear, installation of the upgraded cam button set, and a new cam sensor. I think later kits included the upgraded cam button with the timing set.
You block already has provisions for a roller cam. It would have been cheaper time wise to spend the extra $50 buck for the kit. That said, I do appreciate you taking the time out to do a how to video on cam button install.
DON'T FORGET to support/brace the timing cover where the button will contact it! A 1/16" steel strap the width of the cover, welded to the outside is enough to keep the forward thrust from bending the cover - going from wide open throttle to closed throttle a few times is enough to bow out the cover. There are also thrust buttons that use a steel button with a roller bearing behind it, these use shims as part of the kit to adjust where the button sits - a lot less work than trimming the nylon buttons. You can leave the rear cam plug out while you're setting endplay. Glad you mentioned cam buttons - more than a few SBCs have been "hurt" by migrating camshafts!
For those wondering on using plastic... From my experience it doesn't really matter so long as some positive clearance exists. You don't want it confined, but it shouldn't be sloppy, either. The thrust load from driving the distributor gear and oil pump (on many OHV engines, but not all!) pulls the cam back towards the rear of the engine and holds the cam gear thrust face against the block. The cam button is really only insurance in case the cam walks forward for some reason (e.g. sudden stall). Otherwise it seldom sees any real loading. I have a Torrington one on mine, and with an anodized aluminum timing chain cover, theres no evidence of it ever making contact with the cover. Even the Torrington bearings can only handle about 20 lbs. of dynamic load, so you don't want the cam pushing on the timing chain cover, anyhow, which is why they need a tiny (~.005 - .010") of clearance.
Put a wad of your kid's Play-Doh firm against the end of the cam and through the gear where the button goes, making the wad tall enough to interfere with the installed cover. Bolt and torque the cover on (with the gasket if you are using one) squishing the Play-Doh. Take it apart and caliper the now-formed height of the wad. Add your desired clearance, and viola, a close tolerance estimate for the button trim job. Trial and error works too, don't get me wrong! (Make sure to return the borrowed Play-Doh to your kid!)
It's because you have the wrong timing cover. You're using the flat style & you need to use the one that has the middle sticking out more. It's like a tri-blade design. That cover works perfect.
Google "Cam Plate". Late model GM blocks (88'ish up) have holes already tapped for it. My 89 K2500 (350/5.7 - same as this one) even had the spider hold down bolt holes drilled and tapped as well. ETCG did this the hard way.
@@keithbussanich Yes, its a good tried and true way... they also have spring loaded buttons you don't have to cut. Cam plate is the best way to go if the block is a late model, or you have your machine shop set it up when they have it.
Better way to clearance a nylon is to install button and locktited bolts, punch a hole in a piece of cardboard, place it snugly over the button, shave button some, test fit, repeat as needed.
Video was helpful lol but I don’t have a dial indicator so I measured out some tape I had on the timing cover with a dial caliper. Used a upgraded timing cover with a welded plate so it wouldn’t flex
The advantage of using a metal Torrington bearing one is that you can precision shim the cam button using shim packs behind it. Much quicker than cut and try as above. McMaster-Carr sells shims that will fit the bore in the TC gear, and you can dial it in much faster.
This is a more common problem than people think. Flat tappets do not shift like this. On my wife's '04 Chevy Astro. It stalled out on the highway. The distributor gear was eaten away. We drove other vehicles we have. But as a project I would like to fix it. It is a nice van. In California, the Air Resources people have identified cam walk as a reason vehicles fail inspection. Iskedarian identified this problem on 1960's Chevrolet engines with a roller cam.
I would have had the machinist drill and tap the holes for a cam retainer plate. The casting is there for it on that particular block. It's weird that the holes in the lifter valley are drilled and tapped for the spider plate, but the holes aren't there at the front of the cam for a retainer plate. Unless I saw wrong?
I would think that type of timing cover would flex and allow the cam forward? This cam button crap looks like a good opportunity for someone to design and make a better retaining system and make some $$.
@@chickenfoundation9323 No, his block is a late model. It's setup for a roller cam. You can see the mounting points in the valley for the spider. So it obviously is drilled for a cam blocking plate too. I question how much he really knows about SBC.
I think i would worry about the nylon wearing over time. Drill a hole in a spare cover where the nylon rod is, spot weld a spring steel strip to the cover so it keeps pressure on the nylon even when worn. Good thing i'm not an engineer lol.
With as minor as the adjustments as you were making in the video and doing so by dial caliper. The thickness of a gasket is the difference between an inch and a foot. Your engine.
I've seen the metal ones have a retainer the bolts on using the Cam gear bolts and it doesn't need to be trimmed so why would this plastic one work differently?
I’ve got a ‘89 Camaro IROC with the 305. It has a COMP cam 220 and I have the roller bearing. It’s off by a couple of mms, I’m talking about 2mm. Is it worth to get the nylon and file it rather than using a metal shop to cut the metal to fit? Also would it run against the timing cover? Hope to have an answer ASAP. Thanks!
Why would you use a nylon cam button? It'll wear fast and increase the clearance and affect your timing as the distributor gear moves around. Use the roller baring.
Hello Josh Clark, The camshaft moves...slightly...forward & backward in the gallery on the lubricated bearings due to the force being applied to it. Much of the secondary force applied to the camshaft is from its' interaction with the distributor gear. This "meshing" of the camshaft & distributor gears, tends to pull the camshaft back towards the rear of the block. It is critically important to reduce this front to back movement as much as possible. An acceptable amount is 6 to 10 thousands on the dial indicator. I accept only 6 to 8 thousands max. I know your intelligent question is 2 years old...but...I'm new to this channel. Besides, there's no expiration date on good & interesting questions. 🙂 Best regards from Yucatan Mexico, Ben
With a roller cam, the cam has flat lobes and is free to move in the cam bearings. With a flat tappet cam, non roller, the design of the cam lobes and lifters keeps the cam located.
Does the end of the button contact the inside of the cam cover when the engine is running? If it does, I would expect it to abrade against the cam cover and shorten over time, resulting in increasing cam movement.
Not by much. There's nothing 'forcing' the cam toward the timing cover. It's more like 'locating' it. Also, the engine oil will help protect it just like it does with engine bearings. Thanks for the comment.
Erick you used the wrong timing cover , the proper cover would have an indentation with 3 flanges. also your cover will flex... lastly, you need a cam gear with a Torrington bearing to keep the cam going backwards... im certified Crane Cams valvetrain tech
What kind of fuel economy does this beast get now with the 383 in it Eric? I've been thinking of doing this with my 91 C1500, or putting the Dart SHP 427 small block in it. It's expensive... but would be suhweeeeeet...!
@@ericthecarguy .... Wow..! That is amazing! My stock 350 tbi has never gotten more than 15 mpg.... even on the highway....! And it's only 210 horsepower stock... that 350 is tired with 136K on the odometer. What were your cam specs and max horsepower/torque approx.? Thanks Eric, love the channel!!!
This video was great. Install... hmmm, that didn't work. Disassemble, sand, hammer, ugh. Disassemble, sand, hammer, ugh.... Can't say how many times I've done this sort of thing, the whole time thinking in the back of my mind, "Well I hope this works."
Dude just buy the adjustable button timing cover. Also that block is setup for roller. What are you not just using a cam blocking plate as the block was designed??
@@ericthecarguy Bridge the timing gear with a known setup block and then bridge the cover with a straight edge. Subtract the depth and and the endplay. You can then measure the button from where it seats and turn it down on a lathe. I personally tack a small piece of flat bar inside the cover to reinforce where the button rubs.
People who dislike are pussies who don't own up to it and comment the reason. Even seen a person dislike own up to it and tell the reason? Neither have i.
Who are you, the thought police? People are allowed to dislike something - nothing wrong with that. To be honest, I was disappointed as I have already seen this footage in a previous video - it’s not new content.
![[UA] Team Vitality проти NAVI | IEM Cologne 2024](http://i.ytimg.com/vi/wttO1zVRTC0/mqdefault.jpg)
I love the "Old Car Guy" over-the-glasses commentary, Eric
I can see this face yelling at me as I look over my shoulder..."hit what it goes through, DAGNABBIT!!"
Years ago, back in the late 80's, lots of GM 3800 v6 engines were getting enough mileage that they nerded the timing chain and gear replaced. The original cam gear was aluminum with a nylon material on it. The replacement set was all steel. What GM neglected to mention was you needed a cam button kit in addition to the gear set, and the cam button kit was sold separately. The original timing set had a cam button, made of plastic and a light spring. The upgraded set was metal with a flat roller bearing and a heavier spring, because If you tried to use the old cam button the crank would walk forward and with the new gear being thicker and heavier, the old spring couldn't hold it back, so the cam gear would walk forward and strike the cam sensor in the front cover. You could start the car one time after finishing the timing gear set change, but if you shut it off it would not restart. It required tearing the front cover back off, and replacing the magnetic pellet on the gear, installation of the upgraded cam button set, and a new cam sensor. I think later kits included the upgraded cam button with the timing set.
That sounds like a real PITA. Thanks for sharing that info.
Ouch...
You block already has provisions for a roller cam. It would have been cheaper time wise to spend the extra $50 buck for the kit. That said, I do appreciate you taking the time out to do a how to video on cam button install.
Exactly! The block is setup for roller. He could simply bolt on a cam blocking plate.
No because the camshaft he has does not have the gm step nose
DON'T FORGET to support/brace the timing cover where the button will contact it!
A 1/16" steel strap the width of the cover, welded to the outside is enough to keep the forward thrust from bending the cover - going from wide open throttle to closed throttle a few times is enough to bow out the cover.
There are also thrust buttons that use a steel button with a roller bearing behind it, these use shims as part of the kit to adjust where the button sits - a lot less work than trimming the nylon buttons.
You can leave the rear cam plug out while you're setting endplay.
Glad you mentioned cam buttons - more than a few SBCs have been "hurt" by migrating camshafts!
Hey Eric, nice job showing all of us how to “button up” those tolerances
For those wondering on using plastic... From my experience it doesn't really matter so long as some positive clearance exists. You don't want it confined, but it shouldn't be sloppy, either. The thrust load from driving the distributor gear and oil pump (on many OHV engines, but not all!) pulls the cam back towards the rear of the engine and holds the cam gear thrust face against the block. The cam button is really only insurance in case the cam walks forward for some reason (e.g. sudden stall). Otherwise it seldom sees any real loading. I have a Torrington one on mine, and with an anodized aluminum timing chain cover, theres no evidence of it ever making contact with the cover. Even the Torrington bearings can only handle about 20 lbs. of dynamic load, so you don't want the cam pushing on the timing chain cover, anyhow, which is why they need a tiny (~.005 - .010") of clearance.
Put a wad of your kid's Play-Doh firm against the end of the cam and through the gear where the button goes, making the wad tall enough to interfere with the installed cover. Bolt and torque the cover on (with the gasket if you are using one) squishing the Play-Doh. Take it apart and caliper the now-formed height of the wad. Add your desired clearance, and viola, a close tolerance estimate for the button trim job. Trial and error works too, don't get me wrong! (Make sure to return the borrowed Play-Doh to your kid!)
That's brilliant. Thank you.
It's because you have the wrong timing cover. You're using the flat style & you need to use the one that has the middle sticking out more. It's like a tri-blade design. That cover works perfect.
Do u have a part number
I hate the thought of 1 plastic part keeping your engine from blowing it self apart.
Nylon. Stronger. But yeah, it is what it is.
Ignorance is bliss
Google "Cam Plate". Late model GM blocks (88'ish up) have holes already tapped for it. My 89 K2500 (350/5.7 - same as this one) even had the spider hold down bolt holes drilled and tapped as well. ETCG did this the hard way.
you'd be surprised how strong nylon really is
@@keithbussanich Yes, its a good tried and true way... they also have spring loaded buttons you don't have to cut. Cam plate is the best way to go if the block is a late model, or you have your machine shop set it up when they have it.
I'm enjoying watching your good video.
I support you in Korea.
Better way to clearance a nylon is to install button and locktited bolts, punch a hole in a piece of cardboard, place it snugly over the button, shave button some, test fit, repeat as needed.
Video was helpful lol but I don’t have a dial indicator so I measured out some tape I had on the timing cover with a dial caliper. Used a upgraded timing cover with a welded plate so it wouldn’t flex
Interesting. Thanks for that tip.
Why didn't you use a cam bolt retainer?
Had loctite.
The advantage of using a metal Torrington bearing one is that you can precision shim the cam button using shim packs behind it. Much quicker than cut and try as above. McMaster-Carr sells shims that will fit the bore in the TC gear, and you can dial it in much faster.
Really enjoyable to watch and I also learned something. Thank you.
Could a piece of playdough be used to obtain an impression and the button trimmed to match?
This is a more common problem than people think. Flat tappets do not shift like this. On my wife's '04 Chevy Astro. It stalled out on the highway. The distributor gear was eaten away. We drove other vehicles we have. But as a project I would like to fix it. It is a nice van.
In California, the Air Resources people have identified cam walk as a reason vehicles fail inspection. Iskedarian identified this problem on 1960's Chevrolet engines with a roller cam.
Who cares what California does. You vote for that nonsense.
I would have had the machinist drill and tap the holes for a cam retainer plate. The casting is there for it on that particular block. It's weird that the holes in the lifter valley are drilled and tapped for the spider plate, but the holes aren't there at the front of the cam for a retainer plate. Unless I saw wrong?
It's already there.. covered by the cam gear.
Its already there. For some reason he's messing with the nylon button. I question hopw much he really knows.
Perhaps an idea to remove a semi circle of nylon for each bolt letting the button pass?
So this is just to set the camshaft clearance just like thrust clearance for the crankshaft using thrust washers?
Damn it.
I installed it on the dash.
Next to the starter button
Eric you forgot the cam lock plate
I would think that type of timing cover would flex and allow the cam forward? This cam button crap looks like a good opportunity for someone to design and make a better retaining system and make some $$.
I'd just put a cam plate in it instead of a cam button and use factory style roller lifter retention. I see that others have mentioned the same.
Yes but that requires machining
@@chickenfoundation9323 No, his block is a late model. It's setup for a roller cam. You can see the mounting points in the valley for the spider. So it obviously is drilled for a cam blocking plate too. I question how much he really knows about SBC.
@@SOLDOZERhow much do you know about the cost of a step nose gm camshaft?
Holy shit that thing looks like it could drive you crazy.
I think i would worry about the nylon wearing over time.
Drill a hole in a spare cover where the nylon rod is, spot weld a spring steel strip to the cover so it keeps pressure on the nylon even when worn.
Good thing i'm not an engineer lol.
There's no load on the button.
Straight to the point and I believe I can accomplish that. 👍🏽😎🏁🏁🏁
Once you put a gasket on the front cover it will throw off the adjustments that you made @EricTheCarGuy
Not really. The gasket is only a couple of thousands, well within tolerance.
With as minor as the adjustments as you were making in the video and doing so by dial caliper. The thickness of a gasket is the difference between an inch and a foot. Your engine.
The button is good, but, I WANT THAT JACKET, PRICELESS!! 😡🤟
Watched it on the full build.. thank u
Wierd to see engine block naked....again
I've seen the metal ones have a retainer the bolts on using the Cam gear bolts and it doesn't need to be trimmed so why would this plastic one work differently?
It doesn't work differently. It's just cheaper. $2.
Did you check it with the gasket installed?
No, but I felt the gasket thickness was negligible and still within tolerance.
I’ve got a ‘89 Camaro IROC with the 305. It has a COMP cam 220 and I have the roller bearing. It’s off by a couple of mms, I’m talking about 2mm. Is it worth to get the nylon and file it rather than using a metal shop to cut the metal to fit? Also would it run against the timing cover? Hope to have an answer ASAP.
Thanks!
Great video Eric. Beard is looking good. I need to make my way back to Ohio and stop over and see ya.
lmao, nice LOTR reference
Got to be an easier way to do that, to many variables and it seems like wear would be a factor in short time.
Not really. Remember the oil will help lubricate it.
@@ericthecarguy That's what I keep telling myself about my timing chain guide...
Your supposed to use a cam lock plate to hold the button in
Great vid, keep up the great work.
Would you perhaps have included the timing cover gasket in the measurement? It has to be .040 thick or more yes ?
Edit: Already been asked. Disregard.
I don't think it makes much difference since it would still be within tolerance. Sadly, I cut the footage out about mentioning gasket thickness.
Why would you use a nylon cam button? It'll wear fast and increase the clearance and affect your timing as the distributor gear moves around. Use the roller baring.
Dang good information Eric, Thanks
Good video Eric
Where did you go?
Can anyone explain why the can moves
Hello Josh Clark, The camshaft moves...slightly...forward & backward in the gallery
on the lubricated bearings due to the force being applied to it. Much of the secondary
force applied to the camshaft is from its' interaction with the distributor gear.
This "meshing" of the camshaft & distributor gears, tends to pull the camshaft back
towards the rear of the block.
It is critically important to reduce this front to back movement as much as possible.
An acceptable amount is 6 to 10 thousands on the dial indicator.
I accept only 6 to 8 thousands max.
I know your intelligent question is 2 years old...but...I'm new to this channel.
Besides, there's no expiration date on good & interesting questions. 🙂
Best regards from Yucatan Mexico,
Ben
Why would the cam rock back and forth in the first place?!
With a roller cam, the cam has flat lobes and is free to move in the cam bearings. With a flat tappet cam, non roller, the design of the cam lobes and lifters keeps the cam located.
Awesome video
why do you use 2 valve relief pistons and not 4 valve reliefs pistons what is the difference
Higher compression ratio than 4 valve relief pistons
@@k.lamareyev4418 o okay
You could have just warmed up the spot on the timing cover with an oxy torch and thermally clearanced it.
i.e. melt it.
This is a crap idea, yes.
Does the end of the button contact the inside of the cam cover when the engine is running? If it does, I would expect it to abrade against the cam cover and shorten over time, resulting in increasing cam movement.
Not by much. There's nothing 'forcing' the cam toward the timing cover. It's more like 'locating' it. Also, the engine oil will help protect it just like it does with engine bearings. Thanks for the comment.
You now have whatever your end play was plus the timing gasket ,way to much for a roller cam setup
Erick you used the wrong timing cover , the proper cover would have an indentation with 3 flanges. also your cover will flex... lastly, you need a cam gear with a Torrington bearing to keep the cam going backwards... im certified Crane Cams valvetrain tech
Yes, exactly what I said before reading your comment.
Could you do a video on a 2002 Isuzu rodeo 2.2L timing marks alignment duel overhead cams and crank marks thanks
What kind of fuel economy does this beast get now with the 383 in it Eric? I've been thinking of doing this with my 91 C1500, or putting the Dart SHP 427 small block in it. It's expensive... but would be suhweeeeeet...!
Dad kept track. I think it was somewhere around 16-17mpg. The MPFI is awesome.
@@ericthecarguy .... Wow..! That is amazing! My stock 350 tbi has never gotten more than 15 mpg.... even on the highway....! And it's only 210 horsepower stock... that 350 is tired with 136K on the odometer. What were your cam specs and max horsepower/torque approx.? Thanks Eric, love the channel!!!
So this is like the cam plate on an LS?
Yes.
Those cam buttons do not work with summit true roller timing chains for BBC
Why didn’t you just sand it while it was on the engine. Why did you take it apart every time. 😆
KEEPING IT REAL! Keeps nylon shavings out of the timing chain.
I don't want sand or plastic shavings in my new engine.
There not shavings it’s plastic dust you blow it off with an air hose.
Curious why on earth you would dismantle it everytime? Just leave it on the engine and sand it? Oh Eric
Because I didn't want to get sand or plastic bits inside of my new engine. I took about 1/4" off.
@@ericthecarguy nah.
Nice video straight to the point 💯
This video was great. Install... hmmm, that didn't work. Disassemble, sand, hammer, ugh. Disassemble, sand, hammer, ugh.... Can't say how many times I've done this sort of thing, the whole time thinking in the back of my mind, "Well I hope this works."
Dude just buy the adjustable button timing cover. Also that block is setup for roller. What are you not just using a cam blocking plate as the block was designed??
Because step nose gm camshafts are over 500$
U have been in some bad luck with your engine :( stay strong and you will hit the street soon again :D 🤘
'Nylon'?! Yeah, not a fan of anything but metal going near a source of heat, especially the more heat there is!
THESE VIDEOS ARE GETTING RIDICULOUS JUST LIKE THE FAIRMONT SERIES
joe burkett then don’t watch...
شكرا لك
Fiddly!
Could you please upload the video Acura tsx2010 breaklight assembly replacement..thank you
killer
Just a couple of words, Depth Gauge?
Where would you place it with the cover on?
@@ericthecarguy Bridge the timing gear with a known setup block and then bridge the cover with a straight edge. Subtract the depth and and the endplay. You can then measure the button from where it seats and turn it down on a lathe. I personally tack a small piece of flat bar inside the cover to reinforce where the button rubs.
Bonked it
Woow watches the other video first...
Bye Felicia🤨🤦♂️🤦♀️🤔🤷♀️🤦♂️WT*
🖒🖒🖒🖒🖒👍👌
☆☆☆☆.
Nylon bad, steel good, ask scroll compressors.
Aw man recycle... gay
That one dislike guy
Whats ur problem
There's 2 now... Must be family ;-)
People who dislike are pussies who don't own up to it and comment the reason. Even seen a person dislike own up to it and tell the reason? Neither have i.
Who are you, the thought police? People are allowed to dislike something - nothing wrong with that. To be honest, I was disappointed as I have already seen this footage in a previous video - it’s not new content.
@@Kobafied So the reason you disliked is because you've seen this before? Okay.. At least you owned up to it and told us.
finally! first to comment...yay me!!!