So I get my new motor in after years of gathering parts, slapping things together whenever I have a little extra time & money. Start 'er up, and it runs nice, but lots of rocker noise. Fair enough, so I adjust them using the method described in the Y-book. Done that plenty of times on the old motor, so it goes pretty well. The noise dies down somewhat, but it's still there. My oil pressure is great, and I'm using royal purple break in oil.

Well, I figure, let's drive it a little and see how things go. After putting about 15 miles on it, the noise is getting worse. I pull the valve covers and check the rockers. Clearances are waaaaayyyy out. Pull the rockers off and the ball ends that fit in the pushrods are really worn down on about half of the rockers. Both sides, more wear toward the back than the front. New cam, New rocker assemblies. Needless to say I'm pretty p.o'd at this point.

Next, I take the rockers off my old motor & try them out. They always ran nice & smooth, no wear problems, good oiling, so it's worth a try. Install & adjust, and they sound pretty good. I can see oil coming out of the rockers and dribbling toward the pushrod ends. These rockers use the stock oil overflow tube on the end.

Sure enough, after putting a few miles on, the noise is getting louder again.

Looks like I'll be pulling this pig out & putting the old motor back in for the time being ( it ran great, I just wanted to build something with a little more power) as the car's been off the road for 2 years & I really just want to drive the car.

I'm ticked off enough now to just sell the thing or swap it for a 390, but I'd rather not go through all that for what could be a relatively simple fix. I remember back when I bought the cam there was talk of the groove not being deep enough on some. What's considered "deep enough"? Does this sound like a cam problem, or should I try blocking off the overflow tubes to pressurize the shafts?

It sounds like you are able to see that the adjuster screws are wearing. If that's right, try a new set. Do your adjusters use a lock nut?


Lawrenceville, GA

Maybe the new cam has a drilled center journal when a grooved was called for, or the reverse.

Mike, located in the Siskiyou mountains, Southern, OR 292 powered 1946 Ford 1/2 ton, '62 Mercury Meteor, '55 Country Squire (parting out), '64 Falcon, '54 Ford 600 tractor.

That sounds like a lot of wear for the rocker arm ball and socket in a very short time.  Years ago I ran a 292 for several months by pouring a cup or so of oil over the rockers once a week.  The engine was badly sludged up and I wasn't in a place to fix it. In that time the valves didn't go badly out of adjustment but the rockers started to squeek when they needed oiling again. The point is that a lot of oil isn't needed on the ball so lack of lubrication isn't likely to be the problem.  Are the pushrod cups OK or are they collapsing?

Unfortunately if it isn't a rocker or pushrod problem it may be the cam.  If it is a cam problem it will happen quickly after startup.  When you take the rocker assembly off put a dial indicator in the  pushrod cup and see if the lift is anywhere near what it should be.  If it isn't even close the cam is toast.  If it is close you have the unenviable choice of checking all the lobes as well as can be done with the pushrod and dial indicator or taking it apart and a visual checking to be sure they are all OK.  

 I installed a new cam several years ago and it got noisy fast, probably no more than ten minutes on the new cam (and lifters) and it started sounding bad even quicker than that. It was clearly the cam. For some reason the front 8 lobes were badly damaged and the corresponding  lifters all went from slightly convex to deeply concave except the one that the mushroom end broke off completely. The cam grinder and I never did figure out why the front 8 lobes failed and the back ones were OK.  When new, the lifters looked identical and were installed randomly. 

Keep us posted there is a lot of interest in cam problems right now.

Doug T

The Highlands, Louisville, Ky.

I don't know about "Royal Purple" but I have had my share of cam problems (two flat  in the last few months including Charlies race engine) and the only oil I will use on break-in now is Brad Penn.  I know everyone here has their own opinion on oil but this how I roll. 

   God Bless.   Tim                           http://yblockguy.com/

350ci Y-Block FED "Elwood", 301ci Y-Block Unibody LSR "Jake", 312ci Y-Block '58 F-100, 338ci Y-Block powered Model A Tudor

tim@yblockguy.com  Visalia, California    Just west of the Sequoias

Marc: For that much wear to appear so quickly in the upper valve train, sounds like insufficient oiling. There could be several reasons. Among them; Some replacement grooved cams have too shallow oil grooves. The incorrect or improperly installed cam bearings, as some cams were cross drilled & used different bearings. A plugged gallery coming up from the bottom, (were the block oil galleries cleaned internally really well when rebuilt?) And Royal Purple is synthetic, yes? Some "experts" don't recommend synthetics for break in, although I doubt that is the main problem. In the Classic truck series on the Y- Blk, Nov. 2001, Doc Frohmader discusses the cam bearings issues & there is 3 types of bearings pictured. I realize this info isn't definitive but I hope it helps. Hopefully, some of the engine gurus on this site here can be more specific & zero in on your problems.. Good luck.

Paul

I have been using ZDDP in everything I have that doesn't have roller lifters ever since zinc has been taken out of the oil. So far, so good. I am a firm believer in zinc. When I was a kid in the early 50's my father was a distributor for one of the oils that licensed the patent on zinc. He would call on people in a 1950 GMC pickup. If they were skeptical, he would have me scoot under the old GMC and drain all 8 quarts out of it. Then he would drive about 100 yards and turn around and I would put the oil back in. He sold a lot of oil, and I'm still sold on zinc.

Kenneth

Fredricksburg, Texas

The first set of rockers I had in there were the lock nut type, but I'm confident they were adjusted well, as much as a pain as it is to adjust them. The ones in there now are self locking.

The cam was definitely not cross drilled. I can't say I'm as sure about the alignment of the holes in the cam bearing. There's plenty of oil getting to the heads, but to me it looks like it's coming out of the rockers very weakly.



By the way, to run the engine and watch the rockers without getting oil all over the freshly painted engine, I took a set of chrome valve covers and cut a window in the top between the holes. Plenty of visibility, and the oil stayed where it belonged!



After installing the rockers that are in there now, I warmed it up and rechecked the clearance. While in there I could see that there was oil getting to the point where the adjusters meet the pushrods, because when I tipped the rocker back toward the pushrod I could see a film of oil get squeezed out of the cup. As I said though, when it's running, the oil appears to be barely dribbling out of the holes on either end of the pushrod. I'm not sure how strong that stream is supposed to be, so I don't know if that means anything.



I won't be getting back under the hood until Wednesday. When I do I'll recheck the clearance and see if I can round up a dial indicator to check the lift.

Marc , Did you run the motor in on the initial start up ???( 2500rpm for 20 minutes ) .Are they stock pushrods ?? Are they mismatched (ie .different length ) .I would go with Doug and check the cam lobes with a dial indicator .Just my opinion. Good luck.

Lon

yblocksdownunder

Seems as if I remember someone recently discussing mismachined pushrod cups in that the rocker balls did not seat properly in the cup resulting in excessive wear.

Glen Henderson



Freedom is not Free

Letohatchee, AL