454 mag milky oil

nbchance · 09-03-2009, 03:27 PM

I have a newly rebuilt 454 magnum. I have 10 hours on it and i have just completed my first oil change. My oil dip-stick is probably not installed correctly. it comes almost straight out from the oil pan with a slight curve upwards. At high rpm some oil is discharging out the top of the dipstick. i also am noticing that the oil that comes out looks like coffee with a lot of creamer. I have a fresh water intake system. Seawater comes in, goes through some kind of oil cooler or heat exchanger, then goes through the coolant resovoir, finally traveling through the exhaust manifolds and out through the exhaust. It doesn't seem like my coolant level is down a whole lot.(Maybe slightly) How do i trouble shoot this. Thanks.

c_deezy · 09-03-2009, 03:45 PM

Do a search, well covered topic.

http://www.offshoreonly.com/forums/s...archid=2890020

http://www.offshoreonly.com/forums/g...-oil-pics.html

blue thunder · 09-03-2009, 07:36 PM

Does your closed cooling system have a radiator cap? If so you can get an automotive pressure tester from autozone and pressure test the cooling system. Chance are though it is coming from the exhaust either through cam reversion or leaking gaskets.

PJDiesel · 09-03-2009, 08:26 PM

Dipstick should have an "O" ring at the base where it seats into the pan.

You need to try to narrow down your search for the water intrusion. On a fresh rebuild, gaskets can certainly be the culprit, namely the intake (not sealing at the front or rear water ports).

Next would be head gasket, leaking oil cooler (thing you mentioned down on the opposite side of the motor from the dipstick, or as mentioned exhaust risers or manifolds, then it gets depressing.........
1) Head issues
2) Cracked block

fireboatpilot · 09-03-2009, 09:15 PM

I think he's confusing fresh water with raw water? Raw water comes in from the hull pick up and sometimes into a strainer(not always) that filters out debris. From there it should go to the raw water pump, then to the oil cooler, then to the engine and exhaust.. Milky oil is NO GOOD at all. If this is a recent rebuild, which it sounds like it is, you need to take it back to your engine builder or mechanic. They can perform compression tests on the cylnders and static pressure tests on the cooling systems to find the leak(s) If you have oil pushing out of the top of the dip stick? There is an excesive amount of crankcase pressure and I would guess a failed head gasket.

lake speed · 09-03-2009, 09:55 PM

Quote:

Originally Posted by fireboatpilot

I think he's confusing fresh water with raw water? Raw water comes in from the hull pick up and sometimes into a strainer(not always) that filters out debris. From there it should go to the raw water pump, then to the oil cooler, then to the engine and exhaust.. Milky oil is NO GOOD at all. If this is a recent rebuild, which it sounds like it is, you need to take it back to your engine builder or mechanic. They can perform compression tests on the cylnders and static pressure tests on the cooling systems to find the leak(s) If you have oil pushing out of the top of the dip stick? There is an excesive amount of crankcase pressure and I would guess a failed head gasket.

or he could have too much oil and no windage tray? Its possibly just aerated oil from the crank whipping it.

Full Force · 09-03-2009, 10:02 PM

Crank case pressure is the reason for dipstick pushing out, no other reason for that to happen.

Prob have a head gasket going to get oil and water mix, is it on the oil change or just on dipstick when checking it, you can have condensation in the dipstick and not actually have it in the oil change, but if all oil removed is milkshake you have issues, do not run it anymore, you will wipe out bearing soon causing more damage

nbchance · 09-03-2009, 11:37 PM

lots of insights and possibilities. I have drained some oil into a glass container. i am waiting for it to settle to see if it separates. How do i tell from looking if it is coolant or water in the oil? Also, I only see the oil coming out of the dipstick at high RPM (4500-4800). As mentioned earlier, the dipstick has very little rise from horizontal. Maybe 15degrees or so. Could this be the reason for oil coming out. Will crank case pressures be high while engine is still breaking in?

Full Force · 09-04-2009, 12:46 AM

Quote:

Originally Posted by nbchance

lots of insights and possibilities. I have drained some oil into a glass container. i am waiting for it to settle to see if it separates. How do i tell from looking if it is coolant or water in the oil? Also, I only see the oil coming out of the dipstick at high RPM (4500-4800). As mentioned earlier, the dipstick has very little rise from horizontal. Maybe 15degrees or so. Could this be the reason for oil coming out. Will crank case pressures be high while engine is still breaking in?

If anything the crankcase pressure would be higher while breaking in, but usually even new rings will not have enough blow by to push the dipstick.

if you are closed cooling=antifreeze, not closed=water..

speedreeder · 09-06-2009, 10:38 AM

[QUOTE=Full Force;2946151]Crank case pressure is the reason for dipstick pushing out, no other reason for that to happen.

I do have an issue that happened on a fuel injected 454 when it had oil coming out of dipstick at high rpm only. When the throttle body was bolted on the gasket was turned around backwards and partially blocked the evac. port to the engine and it would build up a wopping 1.5 lbs. and blow oil out!!!!!