2000 380 DA

[Chris-380]

A friend has the same boat and engines as I do. 7.4 horizon fresh water cooled (380hp). He went to change the oil and found water in it.

What are the possibilities and most likely causes (paths) for water to get into the oil and where would you start the troubleshooting?

 

[bfernald0]

Are we talking a lot of water? If so, I would have to say head gasket. Is the engine losing coolant and gaining oil?

 

[Chris-380]

Are we talking a lot of water? If so, I would have to say head gasket. Is the engine losing coolant and gaining oil?

By the pic I shared, I don’t think it’s a lot. I wasn’t sure if it could be from an oil cooler or something simple. Not sure on the coolant part I will ask today

 

[dtfeld]

Oil cooler would be a likely culprit and easily tested. Long shot but has he looked at the risers?

 

[bfernald0]

Are we talking a lot of water? If so, I would have to say head gasket. Is the engine losing coolant and gaining oil?

He should have the oil tested. If it doesn't contain coolant, its probably the oil cooler. This is in freshwater right? Have the coolers ever been replaced? If not, I'd do oil and tranmission coolers on both engines. Would also have the transmission oil tested.

 

[Chris-380]

Fresh water boat entire life
He did compression today, see the numbers in the pic

 

[Chris-380]

He should have the oil tested. If it doesn't contain coolant, it’s probably the oil cooler. This is in freshwater right? Have the coolers ever been replaced? If not, I'd do oil and tranmission coolers on both engines. Would also have the transmission oil tested.

Coolers are all original

 

[Strecker25]

Partially blown head gasket? It’s been running ok? 75 is very low compared to the others but when mine went on my old boat it was basically zero

 

[techmitch]

Partially blown head gasket? It’s been running ok? 75 is very low compared to the others but when mine went on my old boat it was basically zero

Yep, that or manifold/riser issues.

 

[techmitch]

What do the plugs look like?

 

[dtfeld]

With that compression, I'm thinking risers/manifolds and a head job. Even in fresh water those heads/riser don't last forever.

 

[Chris-380]

What do the plugs look like?

Here is what he sent me

Like crap , but no water on them
I changed them half way through last season, everyone said the boat is running rich

 

[Chris-380]

With that compression, I'm thinking risers/manifolds and a head job. Even in fresh water those heads/riser don't last forever.

I havent really heard many manifold/risors issues in this area. I know they rust from the inside, just not a reported problem around here

 

[Chris-380]

Partially blown head gasket? It’s been running ok? 75 is very low compared to the others but when mine went on my old boat it was basically zero

When my heads were bad I had a 90 on one and 100 on another. My guess is heads

 

[dtfeld]

For what its worth.

Exhaust Manifolds

Exhaust manifolds are important, and ignoring them can potentially lead to expensive problems, perhaps an engine rebuild.

www.boatus.com

Unfortunately our boats are approaching the 1/4 century mark, and I'm alway finding things that need attention.

 

[dtfeld]

When my heads were bad I had a 90 on one and 100 on another. My guess is heads

Unfortunately all of its got to come off for a look.

 

[techmitch]

Here is what he sent me

Like crap , but no water on them
I changed them half way through last season, everyone said the boat is running rich

I was taking it slow.
Edit; I quoted the wrong post.

 

[techmitch]

When my heads were bad I had a 90 on one and 100 on another. My guess is heads

That's probably the what, what's the why/root cause?

 

[Chris-380]

What do the plugs look like?

 

[techmitch]

1 looks good, 8 is hidden and 7 looks fair/good.