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SVMistral

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Hi there,

New to this forum, but would appreciate some advice.
I launched my new (to me) sailboat the other day, and had an immediate engine failure. Large popping sound like backfire through the air intake (middle chamber). I pulled the boat again, and took the valve covers off to discover that 3 valves were stuck, and at least 3 of the push rods were either slightly bent, horribly bent, or had come off the rocker arm.
The engine ran perfectly the day before the launch.
I spoke with a mechanic, and he recommended a full head job.
I saw from another post on this forum from a Mr. Langtry at V12 engineering that valve work almost never requires taking the head off.
I am not sure what the best course of action is.
a) replace push rods and reseat the valves - get her turning over and and try to fire her up.
b) follow the mechanics advice and take the head off, for a full inspection to possibly determine any other damage, and/or underlying cause of the failure in the first place.

I think I can get the push rods out of a spare parts engine I own, but the availability of head gaskets etc is of concern. Also, my window for all of this is 3 weeks, before I have to either launch or pay for summer storage.

What would you do?

Thanks for any help you can offer.
Macdara

PS I've attached a few photos where you can see the stuck valve, and also (sorry about the quality) the bent push rod.
 

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I would say your best course of action is to determine what caused the failure...not much history offers so no guess as to why.

As far as doing walve work without removing the cylinder head, I think somebody got it wrong...the factory manual indicates the head has to come off to rework the valves...
 
makomark said:
I would say your best course of action is to determine what caused the failure...not much history offers so no guess as to why.

As far as doing walve work without removing the cylinder head, I think somebody got it wrong...the factory manual indicates the head has to come off to rework the valves...
Click to expand...
Thanks. Yes, I agree 100% on determining the underlying cause, and I take your point on the manual instructions to remove head.

Some history.

The engine was rebuilt by a reputable shop 6 years ago, and has been completely reliable until last year.

The boat was involved in an incident last Autumn. It was briefly exposed to salt-water, but pickled and ran fine thereafter. When I commissioned it in the Spring, I had a failure of the water pump (gear driven) and fresh water leaked into the gears. I changed the oil a few times, and it all seemed fine after that.

So, it's been through a lot - but enough to cause such a sudden and catastrophic failure? Is there anything else that could have caused this to happen?
 
water intrusion would be a candidate, only because the damage is pretty wide in area...that said, I don't have any first hand experience with that particular series...
 
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