Cam thrust button noise

[Cazbah362]

OK, I have built my motor and taken it to the dyno and fired itno issues. Now, after I have put the engine in the car and fired it I am hearing noise (whine) from the front half of the motor (440). I did replaced the following items beofre putting and after dyno session: Rockers from 1.5 440-Source to RAS 1.6, Cam-Oil drive from steel to bronze (Roller Cam) and all the front of the engine. Could all those components make that noise? Any thoughts?? I do have a cam button on the front of the cam.

 

[bigmanjbmopar]

Mech fuel pump? Bronze tip rod needed.

 

[lewtot184]

whats the end play on the cam?

 

[Cazbah362]

Set the end play to zero, it was close to the timing cover. But was not touching when I dynoed, double checked after runs

 

[Hemirunner]

If the end play is zero, no oil will get between the timing gear and the block and it will eat the thrust face off the block. Seen that alot over the years. You need .008-.010" or so of clearance unless you've got a torrington on the back of the gear. Then you can run zero.

 

[lewtot184]

If the end play is zero, no oil will get between the timing gear and the block and it will eat the thrust face off the block. Seen that alot over the years. You need .008-.010" or so of clearance unless you've got a torrington on the back of the gear. Then you can run zero.

i agree with this. i think the minimum should probably whatever the crank end play is.

 

[Hemirunner]

Minimum crank end play is typically .004" which would be tight but fine on the cam. I like a little more as it's not riding on the side of a nice smooth bearing like the crank is. Check for "oil canning" of the front cover. If it's a stock piece with no reinforcement, it happens alot and can be noisy.

 

[Hemirunner]

Another thing I've seen that's scary as hell, is timing chains riding against the block casting on some engines with core shift on the block casting. The factory single roller setup doesn't need near as much room as a double roller aftermarket setup.

 

[Cazbah362]

Thanks guys, I have a true roller with the torrington bearing and the cam thrust button has a torrington bearing. In between dyno and putting the engine in the car, I did double check these issues and all looked good. Like Hemmirunner was saying, always concerned with the chain touching the block, so was concerned and clear at that time.

I guess i need a better explanation of "oil canning." I do have a stock front cover and to me it sounds like the thrust button is touching the cover. From what I read is this common hence the reason for the torrington bearing on the front of the cam button? This is what I think you mean by oil canning? Crank end play was .008

Could the new bronze gear thrust the cam forward?

 

[Hemirunner]

It's basically the front timing cover flexing. You can sometimes hear it when the engine's running and the cam (and hence the thrust bearing) starts tapping as it moves back and forth. You can probably see it by putting a timing light on number one. The timing will jump all over when holding it at a steady rpm because of the flex in the cover allowing the cam to move back and forth allowing the position of the cam gear/oil pump drive to move back and forth altering the timing.

 

[Cazbah362]

Thanks for the explanation, guess what is the fix if that is the case? I guess my concern is with two issues, first the thrust button hitting the timing cover, what are the consequences and issues. I have a true roller chain with the torrington on the back (gear to block) and on the thrust button I have the torrington on the front of the button and the back of the timing cover. On the new bronze gear - well it getting eaten up and the issues it will cause. Thanks for letting me talk through the issue and for your insight, please keep it coming, very appreciative Hemirunner. And anyone else, please chime in.

 

[lewtot184]

personally, i don't like those rollerized cam buttons. if you can find or have made a delron or nylon and trim to fit it'll last longer. the last two rollerized i messed with were a problem.

 

[Hemirunner]

The thrust running against the timing cover isn't an issue. A roller bearing thrust is designed to do that. The issue is the timing cover flexing. This issue is what needs resolved. It'll cause the erratic timing and premature wear of the dist drive gear. I also put a .005" hardened steel shim in between the bronze gear and the bronze gear bushing so you don't have similar materials riding against one another. I've used roller bearing thrusts, nylon and aluminum thrust. All seem to work just fine if set up properly. Also make sure your water pump doesn't put pressure on the timing cover once you reinforce it.

 

[lewtot184]

it would be funny to go thru all this technical stuff and then find out its alternator bearings, lol.

 

[Cazbah362]

Lewtot, I agree I'm doing just that, starting on the troubleshooting. That was my thought as well. I will lets you guys know, I appreciate everyone's help

 

[Meep-Meep]

I had an Isky roller some years back and I had to dimple the timing cover to allow for the roller thrust button. I don't know what my end play was, it had some, but my main concern was not to preload the thrust with the timing cover. No issues and no noise. If you are indeed preloading the thrust with the cover then you may very well hear a noise as the roller bearing may not be loaded evenly.