Thick oil to solve valvetrain noise?

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thejohnnyguy

thejohnnyguy

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I've got a ticking coming from under the passenger side valve cover, I read that the first thing to try is a thicker oil, how thick would you go? is 20w-50 too thick? engine runs pretty well, maybe a slight occasional miss, haven't done a compression test yet. any thoughts? I'de love to just tear this engine apart and figure out what it may be but that becomes difficult since right now I rely on my Scamp to get me to work and school...
Thanks in advance!
 
First thing I would do is pull the valve cover and take a look see. Maybe the rocker shaft loosened up, or maybe the rockers are worn. Do you know any history about the engine?
 
BadAss71 said:
First thing I would do is pull the valve cover and take a look see. Maybe the rocker shaft loosened up, or maybe the rockers are worn. Do you know any history about the engine?
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History of the engine is - it used to frequent the local drag strip before being parks for many years. all I know about it is that it's a 318 block with X-heads and 340 intake, and some aftermarket cam. everything else is unknown. Could very well be stroked, certainly has some work done in order to run the 318 with the X-heads... I did check the rods to make sure they were straight, which involved removing and re-installing the rocker shaft so it's not that...

I need to do a comp test, I believe when I did one many many years ago that I had 1 cylinder with low compression, but I'de need to re-test to be sure
 
Using thicker oil to try and cure a problem is like slapping on a ton of underarm deodorant cause you stink and really need a shower. I can understand you need it but that's simply not the right way to go about it. In an evening you could easily pull a valve cover and investigate things. Just make sure and have a gasket scraper, roll of shop towels, can of brake or carb cleaner, and a new set of valve cover gaskets and there should be no problem yanking the VC, investigating things and putting it back together so you can use it the next day.
 
X heads will directly bolt on to a 318. Just cause it has X heads doesn't mean it has to have had something done to run them.
 
fishy68 said:
Using thicker oil to try and cure a problem is like slapping on a ton of underarm deodorant cause you stink and really need a shower. I can understand you need it but that's simply not the right way to go about it. In an evening you could easily pull a valve cover and investigate things. Just make sure and have a gasket scraper, roll of shop towels, can of brake or carb cleaner, and a new set of valve cover gaskets and there should be no problem yanking the VC, investigating things and putting it back together so you can use it the next day.
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But what should I look for? I've never been that far into an engine so im unsure... I had the rocker shafts off along with the rockers and I pulled the rods to make sure they looked ok, what else could be done without pulling the head off?
 
fishy68 said:
No... An exhaust leak from the manifold or headers (depending on what you have).
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New exhaust manifold gaskets fixed the ex leak that I had in the past, this sounds like it's coming right from the valve cover, it's a tapping sound that gets faster as RPM's increase... I'll get a video tomorrow after my morning classes and post it, maybe that will help a bit.
 
Piece of fuel hose held to your ear sometimes helps finding noise, and especially exhaust leaks.
 
When you have the valve cover off, start the engine and let it run at a slow idle. Run a .010 (or so) feeler gauge between each rocker and valve stem to determine which valve is causing the problem. The tick will lessen or go away when you find the bad one. Inspect the rocker arm socket, bearing surface, push rod end, and rocker shaft for wear. If they look good, it's probably the lifter and cam lobe that're bad. Depending on which one it is, some of the lifters can be pulled without removing the intake. A good magnet or magic fingers can sometime remove them if it's not too mushroomed over on the cam end. If it's bad, you can try putting in a new lifter for a temporary measure but they usually won't last long. When you get around to replacing the cam, use some oil with a higher zinc content to help keep it from happening again. 20-50 works fine on those motors....probably won't help the tick much though...
 
Dont forget a loose flexplate, but the bad exhaust gasket is a good place to start, at idle, just feel around the exhaust ports for puffs of exhaust, or disconnect the fan belt and blow smoke around the ports from a cigarette.
 
My 75 Duster had a tick. I was told it was a sticky lifter. I would dump a quart of Risilone in when the tick surfaced usually every 3 months or so. What can I say I was a broke colege student, couldn't afford to fix it, couldn't afford anything better.
 
UPDATE:: Checked everything over again, should the rocker arms have a little play in them when the lifters aren't putting pressure on them? (non adjustable) - I found at least 1 rod that was definitely bent. I just ordered 16 new rods (for like $32 with shipping included) and I hope that fixes the noise... everything seemed to work properly other than that...
 
my car got a tick in it too. I wipe my cam out when i lost my belt.So i bought a new voodoo cam new lifters and what not and got a tap on drivers side.I think im going to replace the whole rockers and bar and see whats next.
 
thejohnnyguy said:
UPDATE:: Checked everything over again, should the rocker arms have a little play in them when the lifters aren't putting pressure on them? (non adjustable) - I found at least 1 rod that was definitely bent. I just ordered 16 new rods (for like $32 with shipping included) and I hope that fixes the noise... everything seemed to work properly other than that...
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When you install the new pushrods put a little oil on them before install.

Do you know how to check the preload? Did you measure the pushrods that are in the motor or just buy stock replacements?
 
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