Noisy lifters

[sea wolf]

Boat is powered by a 3.0 GM. I have noticed that the lifters are starting to emit a noticable tapping sound. The tapping seems to decrease as the engine reaches operating temp. The oil is clean & I have always changed it & the filter at least once a season, depending on usage. Other than the lifter noise, the engine runs great & starts on a dime every time, knock on wood. The boat is an '87, & I have no idea how many hours are on her, there's no hour meter. Oil pressure is good, about 35-40 p.s.i. Considering the engine runs ok otherwise, what do u guys think?

 

[Sagabu]

Re: Noisy lifters

High RPM or idle?<br /> spark knock ???<br /> Low octane fuel or timing would be my first places to suspect if at high RPMs.<br /> One odd accurance I had w/my 120 that had me puzzeled for a moment (just one)was the oil dipstick. It would rub the crank slightly causing a lifter type sound. I could feel it when the engine was running as I held the handle of the dipstick. I turned it slightly and the issue was gone. Check for that.<br /> Try 92 octane and check the timing .<br /> Bad timing can cause blow by and presure in the crank case that will cause the lifter noise as well as gasket failures. Pop off the oil filler cap and feel for excessive air presure.

 

[Scaaty]

Re: Noisy lifters

Try straight 40wt with a quart of Rislone in place of one quart of oil, and a pint of STP...maybe the old snake oil trick will work. All it takes is a little crap in the lifter to bleed down, and will improve with a warm block. Block is pushing 20 years, time for a winter repower maybe?

 

[Silvertip]

Re: Noisy lifters

Forget the STP but do try the Rislone. If varnish is problem for the lifters, Rislone will take care of it in a relatively short time.

 

[Don S]

Re: Noisy lifters

Make sure your oil level is not over full. If it is, it could be allowing the crankshaft to hit it and aerate the oil. With the aerated oil, you will get lifter noise.<br />Another possibility is if you just changed from mineral to synthetic oil. About half the time, it will cause lifters in older engines to get noisy.

 

[Laddies]

Re: Noisy lifters

Some oil filters will cause lifter noise, I won't name the worst it will start anouther debate. Try WIX or NAPA

 

[sea wolf]

Re: Noisy lifters

I'm not using a Fram filter. I have not switched to synthetic. I'm using straight 30 wt., Valvoline. It may be overfilled just a bit, but not even 1/2 qt. I will drain the excess & see if that helps. What's with the Rislone? I've ssen their ads, but never used it.

 

[Grayhorse]

Re: Noisy lifters

Sea Wolf, recommend changing your oil, and adding Sea Foam to the oil. Works much quicker than Risolene, and doesn't evaporate off as quickly. I've got twin 140 Mercruisers that rattle a little in the spring when I first start them if I don't treat the oil. The lifter bores can get a little spot of rust and prevent the lifter from getting back down to the cam quickly enough. When the engine warms, the bores open up a little more, allowing the lifters free action. You may have more serious problems, but start with the easy fixes first.

 

[crazy charlie]

Re: Noisy lifters

Sounds like a job for Marvel Mystery oil.I have used it for the same problem in cars.It may not get rid of it completely but will surely reduce it.Charlie

 

[djvan]

Re: Noisy lifters

I thought I had a noisy lifter a few weeks ago. 3.0 mercruiser 1986 model, turned out to be a bad cam gear (fiber)<br /><br />DougV>

 

[Sooner44]

Re: Noisy lifters

I have an 84 3.0L Merc. I had the same problem,<br />I switched to Valvoline 50wt oil and all was good.<br />I thought the 3.0 called for 50wt oil ???<br />I'll pull out the manual and check, or maybe someone here knows for sure.

 

[sea wolf]

Re: Noisy lifters

50 wt? Don't think so! Are u sure u don't mean 25w50?

 

[Sooner44]

Re: Noisy lifters

Sea Wolf,<br /><br />You may be correct, can't remember. I do know the last 5 years I have been using straight 50 wt oil,<br />in the SeaRay. No problems with lubrication, oil pressure or anything else. The summer days in Oklahoma are around 100 deg. I really don't have cold starts, Don't really matter, It's my back-up boat now. This new 17.5 glastron is so nice to load / unload and scoot around the lake, I hardly ever put the SR in the water anymore. I have come to love a stripped down, no frills, light weight boat.