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Oil or gas sheen in exhaust water 1986 350 hp 454

A

alan_in_vt

New member
I am starting a new thread here as we have worked on the problem and are at a new spot. Engines are Crusader 454 350hp 1986 with 1,500 hours in a Bluewater 51.

Originally had oil or gas like sheen coming out in exhaust water of port engine. Thought it might be running rich so we started with replacing auto choke...no change. Rebuilt carb...no change. Switched carbs with other engine....no change thus figured not the carb running rich with gas. Sheen really does not have a gas odor. Coolant level good, no water in oil. Compression test showed one cylinder at 135 and the rest in the 150s. The sheen in water kept getting worse. Thought it might be a valve stem seal. Had a valve job done and the problem still gets worse. Noticed a considerable puffing from the valve breather tubes when detached from carb. Maybe 5 times more than the other engine. The oil sheen is now bad enough to be considered a water pollution problem. Suggestions as to the problem and fix are welcomed. I am now considering engine block exchange. Are there any other alternatives? What do you recommend if we have to put in a rebuilt engine.
 
Re: Oil or gas sheen in exhaust water

Alan,

Did you check for the presence of fuel in the sight tube between the fuel pump and the carb. You may have a bad fuel pump.

Erich
 
Re: Oil or gas sheen in exhaust water

We have checked through for the possibility of a fuel pump problem. The exhaust water sheen has no odor of gasoline to it. The sheen does not evaporate as you would expect if it was gas. The engine has always run perfectly and no problems at full cruising speed with no loss of power, no stalling, no "hiccups" of any kind. We picked up some of the sheen with an oil pad and it was brown in color and had no gas smell. At this point I am Pretty sure it is oil.
 
Re: Oil or gas sheen in exhaust water

Have you checked your tranny fluid? Could be a bad cooler that is leeking oil into the raw water circuit.
 
Re: Oil or gas sheen in exhaust water

Is the spark plug corresponding with the 135 psi cylinder looking different from the rest? When the head was off for the rebuild, what did that cylinder and piston top looked like? Scoring, deposits on piston etc?
 
Re: Oil or gas sheen in exhaust water

Based on the "puffing" from the vent hose, can you check to see if the crankcase is experiencing positive pressure?
 
Re: Oil or gas sheen in exhaust water

Hmm, if your not getting smoke out the exhaust and the plugs look ok then also check the oil cooler for leakage into the sea water side and you might see some minor oil residue in the sea water inlet water box of the Hx. A little bit of oil can create a lot of sheen so you might not even see any obvious drop in oil leve on a short run. Also when you close off the vent hoses to check for positive crankcase pressure you might get some oil spitting out of the dip stick tube.

mike
 
Re: Oil or gas sheen in exhaust water

Sorry brother, the engines are at the end of the service life. Don't waste time and money trying to find the reason. 1500 hrs that is the reason.
 
Re: Oil or gas sheen in exhaust water

Its common! My 1984 1900 hours on each engine have done it for years.
It’s just the valves, its like your lawn mower, some oil gets through the valves
and gets into the exhaust. It looks worst then what it real is due to mixing with water.
After 1 minute it goes away. If it does not go away after warm up then you do have other issues.
 
Re: Oil or gas sheen in exhaust water

My 1996 454 "350's" with 780 hrs each do it a bit also. usually just a little sheen on the water when I start them (starboard a little worse than port), but it stops after about two minutes of idling. It is bad enough to notice, but as gastite101 said, it doesn't take much to see that sheen. All my fluid levels remain pretty stable, so I have not gotten to the point where I am worried about it yet.

Just thought I would chime in and say "mine do too."

On a side note, I made a bad internet purchase (two "rebuilt" Rochesters). One of which puffed black smoke, would not rev... or should I say would not BOG over 2800rpms, fowled all my plugs, gulped ~20gph at 2200 RPM, and added a gallon of fuel to my oil in no time flat (sucked-out 10.5 quarts of fuel/oil)... Yeah... now THAT was a fuel sheen on the water! Needless to say my original carbs are back on the boat, and I am debating a lawsuit for all collateral costs directly related to that carb. Sunk float, bad needle valve... I don't know, but F'ed up for sure! Three oil changes later, my oil does not smell like fuel anymore and actually has some viscosity to it again. :rolleyes: Lesson learned... *Pretty and *Expensive does not mean a quality product.
 
Re: Oil or gas sheen in exhaust water

You aren't the only one who got hosed buying carbs on the INet :mad: I bought a total of three and all of them certainly did not perform as advertised....Later I was 'told' one was actually an International Truck Carb that had been 'epoxied' to perform like a marine carb....yeh...really !!!:mad::mad:

Thankfully the guys on this board pointed me to Cliff Ruggles in Mount Vernon Ohio...I sent him one carb last year, he returned it, Installed and used it for the summer on one of my 350s.....That engine has never run that well for the 14 years I have had the boat!!!

I sent him the other carb yesterday, he rec'd it today and I will get it back in April and I am sure it will be done as well as the first. If you don't feel qualified to " play with the heart of the engine", ((I don't)), then I would strongly suggest Cliff is the man to see.

Go here........http://www.cliffshighperformance.com/ you won't be sorry.
 
Re: Oil or gas sheen in exhaust water

Six month turn-around??? Wow! Thanks for the link, but I got a couple recommendations for Orange Engine here in SoCal (local). Same stories, "My boat never ran this good!" I will have to give them a shot first.

Sorry, didn't mean to thread-jack... back to Alan:

If you are convinced it is a problem, and confident it is not fuel, the next step I would personally take is pressure-testing your coolers. I would start with the "U" cooler since you said the sheen looked brown in color. Any radiator shop should be able to clean and pressure-test it for you.

The puffing from the valve cover breathers would indicate positive crankcase pressure; as MakoMark said. A little bit is unavoidable and perfectly normal. Typically, this is caused by cylinder leak-down or "blow-by". That is what the breathers are there for. Plugging the breathers, as Mark said, may cause oil to squirt out of the dip-stick hole, but do not plug them for too long as the pressure may also blow out seals! Have you performed a cylinder leak-down test? What were the percentages?
 
Re: Oil or gas sheen in exhaust water

Eric.C said:
Six month turn-around??? Wow! Thanks for the link, ...........?
Click to expand...


Sorry, I should have been clearer...the 6 month turnaround is because I don't need the carb until May.....Our boats are on the "hard" up here.....winter is creeping into the Great White North. :) :) :)
 
one hybrid option for those of you that are inclined. Buy the kits from Cliff, do your own rebuild and then send them off to Cliff for bench testing. He has a big block that he can run them on.

I was very happy with the results. Saved a few bucks and maybe some turnaround time although I did this off season for me. He was mildly impressed with my rebuilds (ok, maybe that was in my mind :)

Glad I did it because he corrected a couple of minor things. I re-bushed the throttle linkage, strong recommendation and it's easy to do.


Bob
 
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An engine in very good shape wont have any blow by or any tiny amount.
An easy test is to remove the oil fill and see if it smokes out or has any back pressure.
If it has back pressure check the PCV system to make sure it is not clogged.
If the PCV is working and it has back pressure then the rings are likely worn out.

What you can try is thicker oil. Go all the way to 20w-50, might make a difference.

One of my engines has no blowby, it even can develop a crankcase vacuum when running. Plug any breather vent, let it idle and that engine will suck down several inches of vacuum. it is a Palmer IH 392

lowering the crankcase pressures can boost power, likely only at high rpm since less air drag on the moving parts.
Years ago, I set up 2 PCV valves on my engines, one for each valve cover. each line terminates into separate intake manifold ports. This serves to create a crankcase vacuum at low engine speeds. Normally one line would go to PCV, the other rubber hose from valve cover to a connection on the flame arrestor. Then the PCV actually sucks air into the engine thru the breather line attached to the outside of the arrestor.

getting rid of the external breather I think it makes for less fumes in the bilge and a cleaner engine exhaust. I have noticed no increased oil consumption and no running problems.
http://www.gzmotorsports.com/vacuum-pump-guide.html
 
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sdowney717 said:
An engine in very good shape wont have any blow by or any tiny amount.
Click to expand...

Not true. A brand new engine will have a little blow-by. That is what the PCV valve is for; to relieve this seal-blowing pressure back up to the intake.

sdowney717 said:
One of my engines has no blowby, it even can develop a crankcase vacuum when running. Plug any breather vent, let it idle and that engine will suck down several inches of vacuum. it is a Palmer IH 392
Click to expand...

Okay, your INTAKE is pulling a vacuum on your crankcase. Your crankcase itself cannot pull a vacuum.
 
for truth, I have a 95 Saturn which burns a lot of oil around 600 miles a qt due to weak rings.
The engine has what some might call a little blowby. If you take the oil filler cap off while it runs, it only spits a small amount of vapor. Nothing you might consider abnormally bad.
It runs ok, YET it is worn out. The engine is in need of a ring job and new valve seals.

My 94 Buick which uses no oil has zero blowby, when I say zero I mean undetectable. Take it off and zero pressure, zero vapors nada and it uses no oil at all.

An engine in good shape will have undetectable blow by. That racing site talks about running a pump to create a crankcase vacuum, you cant do that if the piston rings and cylinders are worn out.

The PCV does vent the crankcase fumes since all engines make some fumes, just that engines in good shape will have an undectable level when running with the PCV in place and you open up the oil fill.
 
sdowney717 said:
... all engines make some fumes...
Click to expand...

Blow-by.

It is virtually impossible for piston rings to seal 100%. Ever rebuilt an engine? Did you measure the piston ring end-gap? That gap will naturally allow blow-by. The gaps are staggered to 'minimize' the blow-by, but will not completely eliminate it.

Having blow-by does not necessarily mean you will burn oil, either.

So... this Accord I have in my stall right now, with 32,000 miles on it and meticulously maintained by an old lady, has bad rings?

photo.jpg

Granted, too much blow-by may indicate excessively worn rings, and I would start a thorough check-up on the engine if I suspected it, but having blow-by in itself does not necessarily mean time to condemn an engine.

If the puffing from the breathers seems excessive to you, I would suggest compression and leak-down testing the engine.

My Crusader 350's puff a little from the breathers, but all 16 cylinders are between 147-150 psi compression, and the worst cylinder had < 5% leak-down. I am calling mine normal and healthy.
 
sdowney717 said:
, just that engines in good shape will have an undectable level when running with the PCV in place and you open up the oil fill.
Click to expand...

If you have a pcv sucking in vapors into the intake manifold, opening up the oil fill might just let in fresh air, right? If you are going to do a "blowby" test, for whatever reason, I'd think you aught to kill the vapor path into the intake first. At some point, really high blowby will overwhelm the PCV system and create a positive crank pressure, adding direct oil leaks to its woes.
 
diver_dave said:
If you have a pcv sucking in vapors into the intake manifold, opening up the oil fill might just let in fresh air, right?
Click to expand...

I was thinking about this as well. As you said, Dave, opening the filler sounds like it would allow a ton of unmetered air in. Not sure if I would want 15+ inHg on my crankcase at idle.

Side thought... I will start a new topic (fuel systems and vacuum).
 
I am checking to see if you have resolved your problem. I have the same problem with my port engine on my 1986 Wellcraft Grand Sport with 350 Crusader engines where there is an oil or gas sheen on the water. I was ready to attack the carbs but it sounds like it might be something else. Any help from you or others would be appreciated.
 
This is a common symptom of a bad/leaking oil cooler. Either the eingine oil or transmission oil is leaking out into the exhaust. The oil pressure is higher on the engine side and this is why you don't see water in the oil......just out the exhaust. A pin hole leak can turn into dumping 7 quarts out the exhaust.
 
Re: Oil or gas sheen in exhaust water

Having similar issue, I know its been a while since your post; did you ever resolve, and if so, what did you find?
 
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