My 394 runs so smoothly, no smoke or any problems like that, yet it has an annoying ticking going on. It sounds like an individual lifter or rocker arm. I've seen other posts on here with the same issue. How do I find the offending noise maker?

I am familiar with the EOIC method of adjusting lifters on a valve train with adjustable lifters. Can that method be used to find which one of the rocker arms might be loose? I would have no problem putting in a new set of lifters also, but if there is a rocker problem, shouldn't I try to locate that first?

How do you 394 experts go about working on the shaft rocker set up? Do you have change out the whole shaft and all the rockers? How do you
"adjust" or whatever you call it, to get the right rocker clearance?

Any advise would be really appreciated guys!

 

First , get a mechanic's stethoscope , if you don't have one ;
https://www.ebay.com/sch/i.html?_fro...963+oldsmobile

This will allow you to pin point the area where the "ticking" is coming from . Not all ticking noises are made by the valve train .
They can also be due to other things , such as a timing chain or a fuel pump.

If you have determined that it is a valve train noise , then pull the rocker cover on that side .
You can run the engine at idle with the cover off . There will be some oil there , but not the shower of oil you would get with a Chevy .
While the engine is idling , put your thumb on the pushrod end of the rocker , one at a time .
If there is a bad lifter or rocker you will be able to feel it .Individual lifters can be replaced if they are bad.
The valve train "adjustment "is determined by the height of the valve stems . If you have the valves ground , make sure the machinist checks this dimension .
When assembling an engine the valve "adjustment " can be checked as following ;
Each cylinder should be checked , one at a time , with the cylinder in the "firing" position .
You should be able to twirl the pushrod between the thumb and forefinger easily , but not feel any up and down movement .

Rocker arms and shafts can be checked by dismantling them and checking them with a micrometer . Any more than .002 out of round is cause for rejection .

 

Olds engines have a non adjustable valve train. Like stated above you need to find the offending valve and go from there.

 

Thanks Charlie and oldcutlass, do you know if there is a way to check where the rocker arm contacts the top of the valve stem with a feeler gauge?

That is, can you rotate the engine until the lifter is on the base circle of the cam and use a feeler gauge to check the rocker arm clearance?

So if I do the engine running check method, you are saying I will be able to "feel" the one thats ticking when I push down on the offending rocker arm?

I have a Hilborn 8 Stack fuel injection on this 394, and I can actually hear the ticking through the individual stack for cylinder #8, that is, when I cover that stack with a rag while the car is running, it muffles the ticking noise. Perhaps that already narrows it down to only the intake valve? I might as well get one of those stethoscope things, I have seen them in my friends toolboxes, so they must come in handy for other stuff too.

 

With hydraulic lifters there is zero clearance with the lifter on the base circle . This is why you check the pushrod the way I mentioned .
If the lifter plunger is all the way at the bottom of the lifter , you won't be able to twirl it easily .
If the plunger is all the way at the top , there will be clearance . Which can be felt by moving the pushrod up and down .

 

Sometimes rocker arms or pushrods will get worn, and it will sound like a lifter.

 

Yes , you will feel a shock as the valve train takes up clearance and starts to lift the valve .

 

Are you sure that this engine has hydraulic lifters ? If it has Hilborn injection , it may have been converted to solid lifters with adjustable rocker arms or adjustable pushrods .

 

I'm the one that put the Hilborn Fuel Injection on, it is the stock Oldsmobile valve train that came with the 4 barrel, Ultra High Compression 394.

 

That Hilborn is about a 90 in cool factor but a 99% in grief factor for a street driven car. Most other than the old world roundy roundy sprint or drag strip guys pulled them off after a short time on their street machines.. Complaint I heard was that it it became a toggle switch throttle only.. Your millage may differ.... Tedd

 

The Hilborn is no longer a mechanical fuel injection. This 8 Stack was converted to EFI by the folks at Hilborn for me 20 years ago. The car was a Goodguys Street Machine of the Year finalist at the 2003 Goodguys Columbus, Nationals. Won more awards in 2003 thanI can remember. However, I was a fool, and sold the car to a person in California in 2006...I recently made a 4700 mile round trip in 5 days to re-aquire my sweet Olds "Bubble-Top".

The engine did not have this annoying tick when I sold it 13 years ago. I don't believe the owner abused it, hell he hadn't plated it since 2017, he had other "toys". He took the car to a high end shop (Buxton Motorsports) and they put the most beautiful exhaust system I have ever seen on the car. They also added some kind of electric hydro-boost to the 4 wheel brakes, it stops way better than before! He even took the car to the Hilborn shop that I had do the conversion for them to dial it in.

The EFI system is outdated now and want to upgrade it. I have been getting help here on classicoldsmobile.com with that from a post I on CO concerning a crankshaft trigger for my 394. Now this "ticking" has me worried that my priorities are screwed up here, I should fix this first before moving on to the EFI upgrade.

Gosh I don't want to do a whole engine rebuild though, I wish there was an easy way to locate the offending rocker arm or lifter and fix just that...I had the valve covers off to fix a leak when I first got the car home and I honestly could not see any rocker arm wear, or rattle any of them around at all.

The tick gets noticeably quieter as the engine reaches operating temperature, never goes away entirely, but does calm down. How about if I replaced all the valve train.. that is, the lifters, the rocker arms, the shafts, and the pushrods, I know its probably overkill, and with my luck, I would probably have more ticking than when I started!

 

Pour a qt of Rislone engine treatment in the engine and drive it for a few hundred miles. Then change the oil, it may just be some dirt in a lifter from sitting. If it persists, pull the intake and inspect the lifters.

 

I will try the Risoline, although I can't drive my 61 Olds 300 miles in Michigan now, its supposed to snow on Holloween! Can I just let the engine idle for a hour or so over a couple of days to let it do its thing, or does it need to be run under a load?

 

X 2 on Rislone. I think its more times the Rislone is run through the oiling system than being under a load. "drive it a few hundred miles" means several hours of Rislone flowing through the oiling system and lifters.
....Just my two cents worth.

 

I know my 394 would get sticky lifters at about 3000 miles every time without fail. A oil change would do the trick..... Tedd

 

I did an oil change as soon as I got the car home, but I didn't add any kind of treatment like Risoline or lucas, etc. Just some fresh 10W40 and an oil filter. I can't imagine its going to hurt anything to try the additive and let it run for a while. What about that Seafoam stuff that the guys at Advance Auto are always trying to sell me? Is that similar to Risoline?

 

Seafoam is not the same.

 

Are you sure you dont have an exhaust leak? Exhaust leaks up close to the engine can sound a lot like rocker pushrod slap. And you did say it had recent exhaust work.

 

The custom exhaust work was done a while ago, but as you say, I might as well check for a leak.

I ordered a stethoscopes and a 1961 Oldsmobile Service Manual to help me figure this out. Those manuals are normally quite detailed in their instructions, I figure there must be step by step guide on how to remove the rocker shafts, rocker arms, etc.

Ran the car for an hour today after adding the Risoline. Wish I could say the noise went away after 45 minutes, but it didn't...that would of truly been a miracle

 

"The tick gets noticeably quieter as the engine reaches operating temperature, never goes away entirely, but does calm down. How about if I replaced all the valve train.. that is, the lifters, the rocker arms, the shafts, and the pushrods, I know its probably overkill, and with my luck, I would probably have more ticking than when I started!"

If it quiets down when warmed up, it's probably a lazy lifter. You can find it with a stethoscope or a long funnel. I've done several, both Olds, and Cadillac.

 

I found that with high miles, it was fairly common for the rocker tips to get hammered and worn, and sometimes the rocker and shaft got scuffed from wear.

 

I've also found that lifters and cams can wear also, it takes a lot of wear in the rockers or the shaft to get valvetrain noise and its pretty obvious.