milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

[henry1357]

Hi everyone

Noticed a slight tapping yesterday out on my boat, came in and found milky gunge in oil filler.

oil on dipstick is fine no sign of water, boat has been run about 12 hours since service.

power seems fine wot where it should be.

slight rust on joints of exhaust risers

tapping is coming from valve cover, very quiet almost dimissed it as nothing serious.

also noticed exhaust bellows is torn between leg and boat

Any help suggestions would be much appreciated

thanks in advance

henry

 

[henry1357]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

forgot to say engine temp is 175 and good oil pressure

 

[Silvertip]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

On one hand you say you hear a tap from a valve cover and then you say it is very quiet. So which is it? Tap from a valve cover is a loose/worn rocker, sticky or collapsed lifter, possibly a broken valve spring (rather remoe but possible) or a worn or bent push rod. My suggestion is to change the oil but add one Quart of a product called RISLONE (yellow container at any respectable auto store). Use one quart less oil to make room for the RISLONE. The gunky mess will be cleaned up after which you change oil and filter again. How long it takes to clean things up depends on how often and how hard you run the boat. Engine temp and detergents is what does the cleanup.

 

[henry1357]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

Hi thanks for quick reply

The tapping is more of a ticking noise i suppose

What my concern is that i have a crack somewhere

So what your telling me is there is not much to worry about and that the problem will clear itself with a couple oil changes and time on the water.

Have spoken to a mechanic in the boat yard where it is kept and his answer is to start taking it apart to find problem.

changing the oil with an additive is much more appealing to me cost wise just want to make sure its done right.

how do you think the water got in there in the first place

regards

Henry

 

[henry1357]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

have just taken the oil filler tube off the valve cover and there is rust present inside as well

regards
henry

 

[henry1357]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

Hi thanks for quick reply

The tapping is more of a ticking noise i suppose

What my concern is that i have a crack somewhere

So what your telling me is there is not much to worry about and that the problem will clear itself with a couple oil changes and time on the water.

Have spoken to a mechanic in the boat yard where it is kept and his answer is to start taking it apart to find problem.

changing the oil with an additive is much more appealing to me cost wise just want to make sure its done right.

how do you think the water got in there in the first place

also have just taken the oil filler tube off the valve cover and there is rust present inside as well

regards

Henry

On one hand you say you hear a tap from a valve cover and then you say it is very quiet. So which is it? Tap from a valve cover is a loose/worn rocker, sticky or collapsed lifter, possibly a broken valve spring (rather remoe but possible) or a worn or bent push rod. My suggestion is to change the oil but add one Quart of a product called RISLONE (yellow container at any respectable auto store). Use one quart less oil to make room for the RISLONE. The gunky mess will be cleaned up after which you change oil and filter again. How long it takes to clean things up depends on how often and how hard you run the boat. Engine temp and detergents is what does the cleanup.

 

[henry1357]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

Hi everyone

Have just taken off valve covers and both are filled with about an inch thick of the gunge mentioned in earlier post.

As said before boat is running fine

also it has only had little use over the past couple of years

do you think it could be just condensation or something more serious

regards
henry

 

[04fxdwgi]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

Hi everyone

Have just taken off valve covers and both are filled with about an inch thick of the gunge mentioned in earlier post.

As said before boat is running fine

also it has only had little use over the past couple of years

do you think it could be just condensation or something more serious

regards
henry

Condensation, maybe a little rain water. Check make sure your vent hoses going to the flame arrestor are clear. As suggested, give the engine a clean job on the inside, change oil and filter again and see where it goes from there. At 175 deg, should burn off moisture after a good cleaning and run.

 

[Eric 3.7LX Alpha 1]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

How a bout a pic of what your looking at? Would help us out here to see what you see, the filter and/or the valve cover as well as the rockers.

thanks

 

[henry1357]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

Hi thanks for quick reply

Have already cleaned out the valve covers and valves of gunk and have run the engine to see if oil is getting up in there.

On one side there is one push rod with no oil coming past it and on the other side there is 4 not receiving oil

Will post pictures of oil filter once I take off if it looks abnormal

Regards
Henry

 

[Scott Danforth]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

since boat engines do not get over 212 degrees - where the moisture and condensation from the combustion process is vaporized quickly. the gunk you see is oil and water emulsion. should look like whipped milk chocolate pudding. this problem usually comes around on cars in cold weather and short trips. it also happens on boat that dont get run longer than a half hour. at lower engine temps, boats take much much longer to vaporize the water.

if you have checked the oil and there is no water in the oil, then your problem is simply moisture from condensation and the combustion process.

since you have the valve-covers off, rislone most likely wont be needed since your cleaning them out on the bench.

 

[henry1357]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

Hi

Ok thanks for your thoughts and knowledge will let you know what I find once the oil is drained
Regards
Henry

 

[dollarten]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

That ticking noise you hear could be a hydraulic lifter that is bleeding down rapidly and will not maintain zero lash This particular lifter will needed to be addressed as the extra clearance will eventually break something in the valve train . Most likely a failed rocker arm or worse yet it could break one of the valve keepers and the valve will drop into the cylinder . The failed lifter could be due to rust in the check valve and not being able to hold pressure , hence the noise

 

[henry1357]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

Hi

What is the best way to sort this lifter out
Could it be that the sludge in there is starving it of oil and it will right itself once new oil is in and engine cleaned through or would it need specific attention
Regards
Henry

 

[Eric 3.7LX Alpha 1]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

Absolutely the sludge could be the problem.

Did you try and clean out the pushrods?

You will haver to remove the rockers with issue to access the pushrod. Send a skinny wire thru them and some carb cleaner to open the hole up all the way thru it. If they are not blocked then there's a lifter issue, but may very well be the pushrods.

You will have to readjust the valve lash correctly for each that are removed. There is a proper procedure for it.

 

[henry1357]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

Hi
Not yet was going to try and clean out with a couple of oil changes first and see if problem is still there.
Do you think this is a good idea
Regards
Henry

 

[henry1357]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

Also I have read that valve lash is set automatically when rocker is torqued down to 22 lb /ft

Is this correct
Regards
Henry

 

[Eric 3.7LX Alpha 1]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

Also I have read that valve lash is set automatically when rocker is torqued down to 22 lb /ft

Is this correct
Regards
Henry

Yes you are. Here is a link to the Original service manual #25 for your '98 4.3. It is a read only, buy you can print pages as you need.

The valve lash is on pages 3A-28 & 3A-29.

http://boatinfo.no/lib/mercruiser/manuals/mercruiser25.html#/0

 

[henry1357]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

Thank you everyone for your time and comments

My mind is at rest now (at least till I drop the oil tomorrow )

 

[Scott Danforth]

Re: milky oil/gunge in rocker/valve covers v6 4.3 mercruiser 1998

valve lash is set by finding zero lash when cylinder is at TDC, then turn nut 1/2 turn.