Nirvana 1941 Chris Craft

[Chivs]

Nirvana looks fantastic Bob, I’m sorry the mechanical side is letting you down after all the work you and Craig have done but on the upside to have the original motor in it certainly adds to the charm of it and I hope the brains trust can sort it out and get her back in the water doing 25.9 mph!! Cheers mate

[Bob Vic]

Thanks Chivs. The oil report has come back and it isn't too flash. There is metal in the oil plus a small amount of water. Bugger!

[Alan]

Whats the plan Bob, give it a good flush and an oil change an see if it repeats? Did they break down the contaminants? I wonder if the clutch is still bedding in.

[WoodRay]

Whats the plan Bob, give it a good flush and an oil change an see if it repeats? Did they break down the contaminants? I wonder if the clutch is still bedding in.

After being cooked from the failed as supplied NOS water pump impeller, it's starting to look like an internal inspection may be needed. Salt water ingress is another issue.
At the minimum the head should be pulled for a bore and gasket inspection. Regarding the metal in the oil, I'm of two minds. Oil sampling is about trend analysis. Considering the engine oil was never changed after the initial run/s, it could well be residual cast from the machining processes. Then again, the camshaft timing gear is very soft cast iron, and is considered by the manufacturer to be be a "wear item". The gear was also machined to get the correct backlash due to the crank tunnel being excessively bored prior to this rebuild. Also the main bearings weren't replaced as they could not be sourced. That combined with no main cap registers, and no oil filter, common oil for the gearbox and engine, and the list goes on............
Going by the oil sample it's starting to look like the cast iron contaminates are/have put some wear in the bearings.
Erring on the side of caution I think a bearing inspection would be wise too.

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[Bob Vic]

Thanks for responding and posting Craig. I've got a full gasket set plus a spare head gaskert on order from the US. Once they arrive I'll pull the engine from the boat and remove the cylinder head as Craig suggests and take it from there.

[Bob Vic]

By way of an update on Nirvana, there's not a lot to report. The gaskets have arrived from the US but that's about where it sits ATM. I've just had surgery to my hand and then on May 2nd I'm heading in for spinal surgery. So right now Nirvana is on the back burner. One bright spot however is an article published in the Antique & Classic Boat Society's magazine Rudder (http://www.acbs.org) winter 2025 edition. The article is a slightly reduced version of the article which appeared in Club Marine a while back. Unfortunately the mag isn't published on-line as it is regarded as a "member benefit" only publication.