The Stovebolt Site Forums The Shop Area Engine Shop noisey lifter

This is my first post folks, so bear with me. Finally got the 51 1/2 ton built with a 235 that numbers say is a 58-62 engine. Engine was completely rebuilt with a Patricks kit with the "264" 3/4 cam. I'm running Fenton dual exhaust with a professionally rebuilt Rochester cababulator. Ignition is a Langdon HEI. The engine had about 500 miles on it when a lifter sounded pretty loose. Cylinder 5 tappet was at .009 and tightened back up. A couple weeks went by and it's making noise again. Yesterday I tried to dial in the timing with a light and vacuum gauge on manifold vacuum. Needle is fluttering between 13-16. Thanks for any and all input.

Check the lobe lift on the noisy valve with a magnetic base dial indicator and compare it with another lobe. You didn't mention it it's an intake or an exhaust. Compare the lift with another lobe of the same type because there might be a different lift number. Do you have the "cam card" that came with the new cam? My guess is that you've got a lobe going flat because of an incorrect run-in procedure on the new cam.
Jerry

Jerry, I've been through the flatten cam problem some years ago. I had the engine rebuilt and is still in use by someone else. I wrote it off due to not knowing about ZDDP and flat tappet engines.
When does one know when there is a flatten cam lobe? I have never established a base line on any cam I've installed. Do you read the lift specs from the manufacturer and do the math?

Thanks for the quick reply Hotrod Lincoln. I talked to my mechanic who agreed with your opinion. Asked me to yank the oil filter and bring it down so he could cut it open and look. Did that and he said oil don't look bad at all. When we first started the rebuild we had greased everything up with cam lube,used Valvoline VR1 and even put some ZDDP in. Engine was revved right for several minutes and everything looked good. The lifter that was loose was intake on number 5. I don't recall a "Cam Card" but according to Patricks the specs are 264, 19/53, 65/19, 436. I'm kinda in the bummer mode right now but the mechanic who is also a good friend is gonna come by after work and were gonna take the side cover off and take a look. I also checked the bolts that hold my coil on and I don't think they're an issue. I'll keep you informed.

With the side cover off it should be pretty simple to check the lobe lift right at the lifter with a magnetic base dial indicator. If that comes out right, look for a problem with wear on the underside of the rocker arm where it contacts the valve stem. Uneven wear there can make it difficult to get a good lash adjustment.
Jerry

Well, we didn't get to the side cover but found #5 intake rocker arm adjustment screw messed up. The ball is worn down to an off center point with about a 1/16 of metal worn off. Gotta find a new screw now.

Did you check the other ( 11 ) adjuster screws ?

Sometimes it doesn't pay to try to save a few bucks on a rebuild .........just my opinion .


Genuine GM NOS Rocker Arm Adjuster Screws

photo@photobucket

http://i669.photobucket.com/albums/...hrod%20Adjuster%20Screws_zpsxxbzirj2.jpg


I know these are being re-produced for cheap . I've also read the re-pro's DON'T fit like

the original GM rocker screws .

Get yourself some REAL GM adjuster screws.


Dan's GM Obsolete
Chinook, Montana
phone: 406 - 357 -2615

Dan's has ( 9 ) GM NOS GM # 837385


Friesen Chevrolet
Sutton, Nebraska
phone: 402 - 773 - 5538

Friesen has ( 2 ) GM NOS GM # 837385


Chicago Auto Parts
Saint Ann, ILL.
phone: 815 - 614 - 3122

Chicago has ( 1 ) GM NOS GM # 837385


George
'54 3600

Be sure to check the pushrod that mates with the screw- - - -if one is worn the other is likely to have some problems also. That's one of the advantages of a hydraulic lifter setup- - - -parts never actually lose contact with each other, and battering wear is minimized.
Jerry

Thanks guys. I called Dan's Obsolete and they had a couple screws in stock and I grabbed both of them. Thanks for the info '54 3600. I pulled the #5 intake lifter and the #6 intake lifter and looked inside bores with a Snap On snake camera, everything looks OK. Lifters look fine also. I'll have my mechanic friend look also for a professional opinion. I'm leaving for vacation in a few days so I'll let you know when things get done and what happened. Thanks again for your help.

Make sure you are getting oil to the rockers.
Adjusters and push-rods will last a very long time with oil, and wear very fast without.

Don't forget the snake oil! I have had very good luck with Lucas products, My '55 with ancient Pontiac 400 was using oil (dripping) and their oil stop leak plugged it right up.... Just sayin.....

OK, back from the Alaska cruise. Now back to serious business. My mechanic buddy came over, checked the lifters and cam lobes on #5 and 6 and gave the seal of approval. We replaced rocker screw on intake #5 and checked all others. #5 was only bad one. I buttoned everything back up, hit the starter pedal and she fired right up. Purrs like a Singer sewing machine. Thanks guys for your input and thanks for the info on Dan's Obsolete.