Sudden tappet (lifter) noise

[Phizinza]

So in my hydraulic lifter EA81 all of a sudden while driving at highway speeds I get tappet noise out of no where. It's pretty bad/loud. This engine has been good in the past and now all of a sudden this... :-\

I changed the oil, still the same no better.

Could it just be something stuck in one of the lifters? Any chance a cleaner would fix it you reckon? Any ideas on how to fix it apart from the obvious strip the engine down and replace the lifters?

[ruparts]

hi,

check if the adjustment nut backed off on any of the rockers, just rotate the motor and keep checking for any that have clearance. same process as setting them for the solid lifter motor. if you find one with clearance reset it. it is possible that something actually broke, lifter collapsed, or rocker tip, broke valve spring, spring retainer / keepers released, bad pushrod or bent, etc..

[Yo'J]

I'd hope cleaner would break down a clog but ruparts might be right especially if it doesn't ever stop after it started. Wouldn't a clogged lifter be kind of intermittent? If you got a good seal on your oil pump and good pressure, are running 10-30w and its intermittent, I'd bet its a chunk o funk blocking a lifter. Can you use a tube or a screwdriver to your ear to pick out the lifter? I don't know how to even imagine the oil lines inside of an ea81 engine or where the oil goes besides in the fill spout and around my oil pan gasket to my drive way. I've only done a valve adj on an ea81. Farthest I'd gotten one apart yet. Yet!

[Phizinza]

I suppose I'm going to have to crack the rocker covers off and have a good close look. Its constantly there all the time.

 

I run 20w-50 as its warm in Australia and it's an old car. The factory oil pressure gauge reads between 4 and 5 bar while driving.

[Yo'J]

I thought these motors needed a thin oil to pump the lifters and a thicker oil wouldn't do that, am I wrong?

[rxleone]

I thought these motors needed a thin oil to pump the lifters and a thicker oil wouldn't do that' date=' am I wrong?[/quote']

 

Correct. I think a lot of people figure the higher the numbers, the better for an old engine the oil is. While this can be true, for lifter noise it is better to run a lighter oil.

 

Check out this link.

 

Phinanza, perhaps you should try that Penrite 10w-50 they're making now. I've heard good things about it.

[Phizinza]

I could do another oil change and run thinner stuff, but that's money I really do not have right now and the tappet noise started out of no where while running oil which had been working well for a few months... So I don't think it is the oil thickness that is the problem..

[True2Blue]

I could do another oil change and run thinner stuff, but that's money I really do not have right now and the tappet noise started out of no where while running oil which had been working well for a few months... So I don't think it is the oil thickness that is the problem..

 

either if fell out of adjustment or the oil passage got clogged up:-\

[Phizinza]

Took the rocker covers off.. All had 0.35 to 0.40mm gap (I assume this is taken up when there is oil pressure) except the intake on cylinder 3 and 4 (opposite valves), these had over 1.5mm gap! Has something happened to that cam lobe that has ruined the lifters?

Hmmmm :-\

[Subarule]

Some "Marvel Mystery Oil" mixed with your oil would be a good thing to start with, if you're not already using it, and it's available there.

 

I run it in my gas tank faithfully. Have had no need to put it in with the motor oil...yet.

[GeneralDisorder]

Cam lobes might be wiped, yeah. If that's the case look for it to get worse in the near future since it's getting down into the meat of the cam where there is not a hardened surface for the lifter to ride on.

 

Readjust them and see what happens is all I can say. I had a rocker arm disintegrate on my 350 SBC after it sat for a lot of years. I did an adjustment and it's been fine - maybe it's just in need of an adjustment after years and lots of miles.... I was told that my cam is either wiped or the rocker studs are backing out of the heads. The engine is a '79 so personally I think it was just high mileage and never adjusted.

 

:-\

 

GD