I installed a new cam and double roller timing chain on my 350. But now the top sprocket that goes on the cam is hitting the block before it bottoms out on the cam. Ik there is some kind of shim that goes in between there but I cant find one. Anybody have any experience with this? Thanks!
CK5
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HELP! Timing Chain Sprocket Problems
- Thread starter Cili
- Start date
The cam gear rides/rubs on the front machined surface of the block, there is no shim/washer from the factory.
you sure you got the gear facing the right way ? the dot should be facing out towards you
But the sprocket isnt even touching the camshaft, and the instructions for my came say some motors come with it and iv talked to a few people that said they have seen it before. And yes the sprocket is on the right way.
kauzenkaos
1/2 ton status
Just ran into the same problem this week. Built a gm performance short block for a customer and had to notch the upper section of the top oil galley. If you go to edelbrock and look at there double roller timing chain instructions (think there listed on summits website) it also talks about clearancing the the block there.
Guess its only common on newer blocks. Not that ive built very many sbc's but on the few i have its the 1st time ive had to do it.
http://www.performancedepot.com/ART/products/100626/7800_Inst.pdf
heres the link bottom right corner of pdf
Guess its only common on newer blocks. Not that ive built very many sbc's but on the few i have its the 1st time ive had to do it.
http://www.performancedepot.com/ART/products/100626/7800_Inst.pdf
heres the link bottom right corner of pdf
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kauzenkaos
1/2 ton status
I put a plastic bag around the engine since the crank and pistons come installed. covered all the holes and taped everything up good and went to town on the galley boss with a cutoff wheel. spent lots of time cleaning up my shavings and went back on with assembleing my motor.
I looked at that and i think i have a different problem than that. My chain doesnt touch. It seems like the resessed area in the back of the sprocket is deeper on the new one so the sprocket hits the block. It also needs to be spaced out about 1/16 to line up with the bottom sprocket.
63chevyll
1/2 ton status
No shim, the block needs to be ground down. No biggie, happens all the time, and like stated above it can be done while in the truck with no problems.
kauzenkaos
1/2 ton status
Have you tried installing the ballancer and torquing the bolt to make sure the crank gear is installed all the way?
Bad thrust land or bearing for crank shaft? Does your crank shaft have any end play?
Bad thrust land or bearing for crank shaft? Does your crank shaft have any end play?
I dont have the balancer right now but im pretty sure its on there all the way. And yes I just noticed while messing with this that there is a little bit of end play. There is supposed to be some tho right?
63chevyll
1/2 ton status
I.don't know spec, but no more than .015 of crank end play....that's even too much
kauzenkaos
1/2 ton status
.002 to.006
Figure as thick as a hair or less
Figure as thick as a hair or less
kauzenkaos
1/2 ton status
Depends on how the thrust plate is worn. I mostly see it on vehicles with cheap high stall torque converters that aren't equipped with a balloon plate. Or converter hubs that aren't greased prior to install. Manual to auto swap with pilot bearing still installed (if you can get the bell bolts started). But you can figure anything that puts excessive foreword or rearward force on the crank. By the way im definatly no expert just a few things that i can think of best bet is to find a good machine shop and ask them.
kauzenkaos
1/2 ton status
Not sure how i missed this but when your cam bolts are tight the cam should slide in and out a touch. Is your cam pushed in past flush with the face of the block? Dont think its possible but maybe your fuel pump pushrod is in front of the lobe or maybe your distributor gear is holding the cam back some how.
Crankshaft thrust should be between .005"-.010" and I like to see them right about .008". The cause for excessive thrust is a bad thrust bearing or crankshaft thrust surface caused by either a bad torque converter, bad engine ground, or in the event of a manual trans a misadjusted clutch fork.
What year engine do you have? Is it a roller block? If it's a roller block then there would be a cam thrust plate required which also uses a different timing gear set than a standard flat tappet cam.
What year engine do you have? Is it a roller block? If it's a roller block then there would be a cam thrust plate required which also uses a different timing gear set than a standard flat tappet cam.
kauzenkaos
1/2 ton status
Guess my information was wrong
