Must both inboard Volvo diesels be replaced?

[roden911]

I am considering buying a 1989 29' Phoenix Convertible with twin 200hp Volvo inboard engines. One of them seems fine but the other has water in the oil. I'm told it may be a blown head gasket but what is the likelihood that it is a cracked head, block or something else? If the engine has to be rebuilt or replaced, I was told that both engines should be rebuilt or replaced at the same time or they would never be able to be balanced; is that correct? I was also told that if the water has sat in the block for more than about 30 days, then is is trashed. Again, is that correct? Finally, any input on the cost of repairs for each of the possibilities would be much appreciated. Thanks.

 

[Bondo]

Re: Must both inboard Volvo diesels be replaced?

I'm told it may be a blown head gasket but what is the likelihood that it is a cracked head, block or something else?

Ayuh,.... Welcome Aboard,.... I'd count on it bein' a Cracked block....

I was told that both engines should be rebuilt or replaced at the same time or they would never be able to be balanced; is that correct?

Sounds Bogus to me...

I was also told that if the water has sat in the block for more than about 30 days, then is is trashed. Again, is that correct?

If it's Saltwater,... Ya, probably right... Freshwater,..?? Maybe,.....

 

[Vosman]

Re: Must both inboard Volvo diesels be replaced?

200HP Volvo is a 200HP Volvo. Change because of "balance" ???? That generation is rebuildable. Coolant in oil or salt water? Engine block and head are in a closed cooling system. Antifreeze should have been in it. Cracking should not have been an issue.

 

[roden911]

Re: Must both inboard Volvo diesels be replaced?

200HP Volvo is a 200HP Volvo. Change because of "balance" ???? That generation is rebuildable. Coolant in oil or salt water? Engine block and head are in a closed cooling system. Antifreeze should have been in it. Cracking should not have been an issue.

OK, thanks for the input. Clarification: If one engine has to be rebuilt, does the other one have to have to be rebuilt as well?

 

[RogersJetboat454]

Re: Must both inboard Volvo diesels be replaced?

OK, thanks for the input. Clarification: If one engine has to be rebuilt, does the other one have to have to be rebuilt as well?

No.
As long as the other engine is in sound running condition, and has not suffered the same fate as its bilge mate, it does not need to be rebuilt.

 

[roden911]

Re: Must both inboard Volvo diesels be replaced?

The reason for rebuilding or replacing both engines and the balancing comment from the mechanic I talked with was that if you don't one of the engines would be operating at a higher horsepower level than the other and would creating "all kinds" of issues. Makes sense?

 

[RogersJetboat454]

Re: Must both inboard Volvo diesels be replaced?

Engine block and head are in a closed cooling system.

We don't know that. The O.P. could very well have a raw water cooled engine, which sounds like the more likely scenario given the troubles he has now.

 

[RogersJetboat454]

Re: Must both inboard Volvo diesels be replaced?

The reason for rebuilding or replacing both engines and the balancing comment from the mechanic I talked with was that if you don't one of the engines would be operating at a higher horsepower level than the other and would creating "all kinds" of issues. Makes sense?

Makes sense if you want to replace a perfectly good running engine for the sake of selling 2 engines. Honestly if the compression is within spec's on the "good" engine, and it has not cracked, there is no reason to replace it. If the compression is low, and it's tired, you may want to consider it.

Only other thing I will say is that who ever builds the new engine needs to built it to the same spec's as the other engine if it's a keeper. Pistons, heads, cam profile, compression ratio should all be kept as close as possible to what the other engine is.

 

[Bondo]

Re: Must both inboard Volvo diesels be replaced?

The reason for rebuilding or replacing both engines and the balancing comment from the mechanic I talked with was that if you don't one of the engines would be operating at a higher horsepower level than the other and would creating "all kinds" of issues. Makes sense?

Ayuh,.... I'd think it has more to do with Balancin' His checkbook, than balancin' the power in the hull...

 

[sasto]

Re: Must both inboard Volvo diesels be replaced?

If she were mine.....I would take an oil sample on the good engine and have it analyzed. If all is well.....leave it alone.


BTW...I had a 29' Phoenix, what a great boat!

 

[roden911]

Re: Must both inboard Volvo diesels be replaced?

Thanks, Guys; I'll let you know how it turns out.

 

[Don S]

Re: Must both inboard Volvo diesels be replaced?

We don't know that. The O.P. could very well have a raw water cooled engine, which sounds like the more likely scenario given the troubles he has now.

Actually, all of Volvo's 30, 40, series diesels have a closed cooling system, but you are correct, if you're not familiar with Volvo diesels, there is no way of knowing that.

Assuming the engine didn't freeze, it may be as simple as the oil cooler failing allowing water into the engine.
Compression tests, leak down tests, and cooling system tests will find the problem, and help determine if the engine is salvageable or not.
From the sounds of things, none of that has happened.
Assuming you haven't been loosing coolant from heat exchanger, you don't have a head gasket problem.

Has your mechanic ever been around a Volvo diesel before?

 

[roden911]

Re: Must both inboard Volvo diesels be replaced?

Actually, all of Volvo's 30, 40, series diesels have a closed cooling system, but you are correct, if you're not familiar with Volvo diesels, there is no way of knowing that.

Assuming the engine didn't freeze, it may be as simple as the oil cooler failing allowing water into the engine.
Compression tests, leak down tests, and cooling system tests will find the problem, and help determine if the engine is salvageable or not.
From the sounds of things, none of that has happened.
Assuming you haven't been loosing coolant from heat exchanger, you don't have a head gasket problem.

Has your mechanic ever been around a Volvo diesel before?

I haven't chosen a mechanic but will in the next day or two. I can tell you since I am in Arizona as has the boat (I assume) the engine hasn't frozen.

 

[roden911]

Re: Must both inboard Volvo diesels be replaced?

I haven't chosen a mechanic but will in the next day or two. I can tell you since I am in Arizona as has the boat (I assume) the engine hasn't frozen.

Don, I may have misinterpreted your meaning regarding whether the engine froze; I'll bet you meant whether it froze as in locked up. Correct?

 

[Don S]

Re: Must both inboard Volvo diesels be replaced?

Don, I may have misinterpreted your meaning regarding whether the engine froze; I'll bet you meant whether it froze as in locked up. Correct?

No, I meant freeze as in cold, turned to ice. Since you never mentioned you were in AZ and it didn't freeze, this time of year water in the oil from freeze damage is quite common.

I also assumed you had a mechanic, since there was a lot of "I was told", and "the mechanic I talked with " comments in your posts. I though were trying to confirm what they were telling you.