390 rinker 8.1 volvo oil backpressure

Dan

I have a 2006 390 with 8.1 Volvo osi bought new. This year when I put it in the water I started getting oil in the bilge. Upon investigating  with only 600 hours I saw it was coming out the dipstick. oil pressure is same as other engine no loss of power. Manual says no PVC valve how does it handle back pressure. Any help would be nice

Black_Diamond

Are you over filled?  Water in the oil?

Michael T

Head gasket?

F1100

check the fill level of the oil....if its overfilled...remove the excess ASAP.

do a compression check, an see if 1 cyl is down on compression and you are getting serious blow by.

check to make sure dip stick is engaged correctly and that its not loose.

check your valve cover breathers and see if they are pissing oil as well.

as above... check head gasket as last resort...

check oil , if its milky brown or not...for water contamination or coolent

Michael T

Closed cooling? If so, is the level down in the reservoir?

Dan

Thanks for the responds oil not overfull no water in oil and dipstick is in all the way. I was hoping for an easy fix will have to do compression check and pull motor. Mike it is closed coolant what would that have to do with the oil??

212rowboat

in MT's absence:  if it's closed, check your coolant for oil... the only place oil and water or coolant cross paths is if a headgasket is blown... well, the most likely place, anyway... it can happen with a blown intake manifold gasket, but that usually manifests itself immediately after that job is done, and rarely develops.... 

there are some things that don't make sense.  if you had a gross leak of pressure, you'd certainly notice it.  you said there is no loss of power... the engine produces by-pass gasses, as any engine does- it's not back pressure... that's something altogether different... bypass is gasses slipping past rings and pressurizing the crank case... if you see oil frothing, it's most likely overfilled or there is substantial by pass- if there is that much by pass, there is something wrong to the point you'd feel loss of power... 

do this... take your oil fill cap off and fire the engine... rest the cap on the tower but don't thread it... is there enough bypass to push the cap off?  if there is, there is an issue- if there isn't, there most likely isn't an issue.  

my guess is you're overfilled and just don't know it... it's way to easy to do and everyone has likely done it whether they realize it or not... it doesn't take much to reach the windsor tray, and when that happens and the oil is being slapped about, there just ain't no tellin' where it will go... 

Dan

Thanks rowboat I will try tonight

Dan

it continues I just remembered that when I opened the boat this spring there was anti-freeze in the bilge and had to top it off (maybe a cup to cup and 1/2). This has not happened in the past years. When I opened the coolant res it had a pressure sound like opening a fresh beer could this mean anything???

212rowboat

if you know someone (maybe parts store will rent one?) get an air-lift tool and a compressor, and draw a vacuum in your cooling system... draw about seven or eight inches of vacuum- and wait... a matter of fact, walk away... come back in half an hour... you should be holding that vacuum precisely where you left it... if you aren't, then your system is compromised somewhere plain and simple... then it comes to figuring out where... 

Dan

Thanks I will tell my mechanic that when he comes to do the compression test

Dan

Ok DID THE COMPRESSION TEST LAST NIGHT AND 7 CYLINDERS WERE AROUND 185 AND 1 AT AROUND 55 SO ENGINE COMING OUT THIS WEEKEND TO FIND OUT WHAT HAPPENED AND FIX

jme097

Ugh. Sorry Dan. But atleast theres an end in site at this point

F1100

Cha Ching.. that sucks... but is what I thought. You will most likely see a chunk out of the piston ring or land. Perhaps part of the valve broke away? or maybe just a land failed? or the ring. Hopefully your bore is not all messed up. Depending on how long you ran the engine.  You will 100% see when you pull the head. Which is what I would do first. Pull the head, its quick and easy. And will allow you to see what is going on, and determine what to do next.

when ever you get pressurization like that its a good sign you are getting blow by.

When I was using high power turbo engines, when we saw crankcase pressurization it was a sure sign that some sort of blow by was happening, its never a good sign.

And on the cheap low powered NA engines..I would run them until they balled up. And I actually mean balled up, as in the pistons would be balls of metal at the end You would be suprized how long a engine can run on 2 cyl with the other ones slapping around

F1100

You can pull the head yourself, its easy, just follow the detorqing procedure for the head. It will take you 30min or so. Once you get the head off, and have a look, post the pics. If the engine is toast it makes it way easier to decide what to do..and the extraction process as well. (if its a bad engine you can be nasty with the extraction)  if the engine is salvagable, then you have to be nice to the engine.

this is also a time to upgrade to a better engine..or perhaps engines

since you should 100% check the other engines compression as well while you are at it.

212rowboat

I'd pray upon prayers that a rocker broke... it makes sense with 55psi remaining in a cylinder that's a possibility. 

Dan

I bought the boat new (my 3rd Rinker a 310 and 342) this is going into my 9th season and have had zero problems in over 600 hours I think I will keep the motors that are there but thanks for all the other info.:)

F1100

rocker wont explain the blow by. The crank case is being pressurized not the valve cover

212rowboat

It's a Volvo... Doesn't have pcv valve.. it's a straight shot through the lifter rod passages to the valley and to the crankcase.  Like I said, though, pray... not likely.. 

F1100

cross your fingers then cause that would be WAYYYYY better

212rowboat

I wanna be optimistic until I can't anymore.. right now on my right, I'm praying rings on my rebuild just haven't seated... wanna talk about blow by?  This thing is huffing hard core. It only has about an hour if that on it though. 

Michael T

I would worry at 10 hours, not before.