Have i got a BHG?

[Anonymous]

Took the boat out on the weekend. It goes well, pulls us out of the water no problems, and is all good, performance-wise.
But when you're giving it some (not when you're idling), it spits a large amount of milky oil out of the dipstick hole.

Is this a blown head gasket?
Do i need to replace the head or replace the whole engine (again)?

Thanks.

 

[SONNY]

if its blowing it out of the dipstick hole then it has to be in the sump.sounds like its gone,it only takes half an hour to pull the head off and have a look.

 

[Anonymous]

No replies? Is this forum dead?

Will i need to replace the whole engine? Or just get the block and head shaved and a new gasket and bolt it back together?

 

[addo]

Do a compression test, both wet and dry. That'll tell you a bit more.

 

[MRJLB84D]

if its blowing it out of the dipstick hole then it has to be in the sump.sounds like its gone,it only takes half an hour to pull the head off and have a look.

i agree, pull off the head and check it out...by the sounds of it water and oil are mixing somehow and a buggered head gasket might just be it...but u never know

 

[Stubby]

First drain some oil and see if the milkyness is water in the oil or condensation. Boats see alot of heat and cool cycles and they are suceptable to condensation.

If it is condensation check the pcv system and possible causes for crankcase pressure.

If it is water in the oil pull the head and see how it got in there.

 

[Anonymous]

Well, the pcv valve rattles when you unplug it and shake it around. I read in the workshop manual that that is how you test it.
And its not condensation - there's not *that* much condensation. And condensation doesn't explain the oil spitting out of the dipstick.

My thing is - i'm 99% sure its a BHG, but i can't explain whats causing the oil spurting from the dipstick ??

 

[Stubby]

If you blow a head gasket depending on where it blows the cylinder pressure can become crankcase pressure. All of this air has to go somewhere, it will blow the dipstick out sometimes.

Just because the pcv valve rattles it doesn't meen the system is working. Over here we have Dirt Dobbers. They look similar to a wasp and they will stop up any open hole and many places you wouldn't think they could get into. They have made me lots of money over the years. Which is ballanced out by the headaches they have caused me.

I am just saying don't assume anything. All too often, someone has a problem, removes the problem, has the engine repaired or replaced and reinstalls the problem. It can be an expensive education.

 

[2nd.gunman]

are you running a water cooled sump? it could possibly be a split or cracked cooler pipe causing water to be pushed into the oil during acceleration, have you tried running the engine out of the water? does the same thing happen? as this is in a marine application you need to consider other variables not found in a car

 

[Anonymous]

yes it has a watercooled sump. Water leaking from the sump into the oil is a possibility... good thinking!
And ok i'll check the PCV out, that might be a possibility.

 

[L6]

yes it has a watercooled sump. Water leaking from the sump into the oil is a possibility... good thinking!
And ok i'll check the PCV out, that might be a possibility.

I seem to remember the sump required repairs after the previous engine threw a rod. The pressure from the cooling tapping in the jet unit is quite high and the water will sneak through any little crack.

Before pulling the engine apart there is a quick test.
Fit a piece of clear plastic hose about 1m long to the inlet of the sump cooler.
Secure the open end of the clear hose up high as it will go above the engine.
Pull off the sump cooler "out" hose where it connects to the engine inlet.
Connect a garden hose into the open end of the "out" hose, then turn on the garden hose to a very low setting to bleed out all the air until the clear tube does not show any bubbles.
Remove the garden hose, allow the height of the water in the clear hose to fall about 300 mm below the open end of the hose, then securely block the end of the "out" pipe.
Fit a tubeless tyre Schrader valve stem into the open end of the clear hose and secure it with a hose clip.
Pressurise with a hand pump or battery operated type pump, but do not go above 15psi (100kpa).
Open beer and wait to see if the water level falls.


.

 

[xdee]

Very good advice I'm sure, Peter.
But I don't understand your last sentence.
Clearly, it should read "Open fourth beer and wait to see if the water level falls"


.

 

[addo]

Beam and Cola?

 

[Anonymous]

That's a brilliant idea!

 

[xdee]

Beam and Cola?

You know it Addo, don't mind if I do.

 

[Anonymous]

One of my dad's mates came around - hes good with engines apparently.
He did a compression test, dry then wet, and reckons #1 has a burnt valve, that the head gasket is fine, and that the sump is leaking water, which the crankshaft is stirring into a crazy froth which is spitting it out.
All sounds believable to me.

 

[Roath]

Hey chub

I'm pricing up doing the same thing as you did with my pre cross flow Hamilton Jet.

Can I ask a few questions.

Why did you need a carb wedge?
Why did you need to modify the engine cover?
Was there a noticeable improvement in performance.. what about fuel economy?

Is there any advice? I have all your threads book marked and there heaps of good advice there.. just have to decide what motor to go with. The one with the narrowiest intake manifold would be the winner I think ( and one that has lots of grunt around 3000 rpm as thats my current WOT)

Theres a nice eb2 motor going cheap over here.. have not idea if thats compatible.. Im tempted to do exactly what you did so I can follow all the advice!

Cheers

Rob

 

[Anonymous]

Hey mate,
Email me if you want to have this discussion. Ive since sold the boat, but am happy to give advice, but i don't come to these forums any more.

my email:
chris.hulbert at gmail.com