View Full Version : Marine Power 350 FLV in X-18

02-19-2011, 06:17 PM
Hi Gang-

Now that the snow in my yard is down to 2', I figure it's time to start gathering parts in preparation for some engine and engine compartment work. Last year I picked up my '76 X-18, #136, which has the original Marine Power 350 FLV w/ the 'Vette valve covers. It runs like a top, but seems to collect a bit of condensate in the crankcase. I've spent part of the afternoon combing the threads about the water and feel it's probably due to the fact that we really only have run it in short bursts, never running it for over an hour at a time. The motor's really ugly cosmetically as well, so I figured I'd pull the mill, paint it, clean up the engine compartment, and replace the intake, exhaust, and riser gaskets while it's on the stand. I also thought I'd put in a 160 deg. thermostat. Is it still possible to get parts for this engine, in particular the riser and thermostat gaskets? And can anyone give me any more info on the motor? I've read that it puts out anywhere between 300-330 HP. Some reading I've done on a Chris-Craft site claim that the FLV is a Corvette motor, while other posts claim that it is a hodge-podge of various leftover parts, and the only part related to the Corvette is the valve covers. I know that Kirby had one, and I'd like to mirror his engine compartment restoration.


02-21-2011, 06:58 AM
Before you tear into it get it running and do a compression test! The base engine is just a stock marinized 350 parts should not be an issue, you may still have the old style Chris Craft manifolds and risers with the wye valves they may be hard to find. The wye valves are the fittings on the inside of the risers with the T-ed hose going to them, they can easily be done away going to new exhaust. They were a pain to begin with, never made much sense why they had them. The Tstat will help a lot with the condensation, one thing you should do is to pull the valve covers and inspect the valve springs, it is fairly common for them to rust from the condensation. If they are rusted fair chance one or more will break, if they are rusted you have options depending on your compression test! If the compression if off pull the heads and have them done with new springs, if the compression is good you can change the springs using air pressure to hold the valves in place. You will need the fork type spring compressor, pretty easy stuff I have done quite a few. Phil

02-21-2011, 07:33 AM
Thanks, MOP! I will definitely do that before I pull it. It does have all of the original log-style CC manifolds and risers. I spent some more time yesterday looking for OE-style replacements and found that Barr Marine makes them. I like the fact that my X still has most of it's stock equipment, right down to the original Rocket trailer, and plan on trying to keep it that way.

Just Say N20
02-21-2011, 09:04 AM
Very small world.

I also owned a 1976 X-18, which was sold to someone in NH back in 1985-ish. The boat was Hull ID # DMR1813705 76-X, so it was the hull one after yours. Mine originally had a Volvo 270 with the e-drive lower (speedmaster looking lower unit).

Here is to a link to the ad I put together for the current owner (I don't know if he still has it) back in 2009.


He offered to sell it to me about a month after I bought the 1967 Ski-Sporter I have right now. I would have preferred to have that boat again. I really like the X-18.

02-21-2011, 06:07 PM
Small world indeed! My X spent a few years in New Hampshire as well. It was originally purchased and spent the majority of the time in the Midwest, until it was sold and brought to NH, and then sold to me. Now it'll spend spend it's time in the Sebago Lake area of Maine.

It was originally a caramel brown color.

mike o
02-22-2011, 09:53 AM
Has an engine shop with an excellent reputation. Ill see ya on Sebago next summer. Hopefully with everyone else on Long lake and the Songo River crew.......:wink: We should all run in the Sebago poker run together.:crossfing:

02-22-2011, 06:01 PM
Good to hear that, Mike! I pass by Dorr's all the time on the way down 302. I was thinking about the Poker Run last night. My wife's due date for our baby girl is June 15th, so It'll all depend on how smoothly things are going for her at that time. Regardless, I've got a feeling that we'll be spending a ton of time up there towards the latter part of the summer.

BTW, I do know Mr Magoo...He hangs w/ one of our neighbors; right where you saw me putting in last summer. Cool guy...I really liked his Cigarette. I wonder what he'll get next.

02-22-2011, 09:36 PM
I have the 350 FLV Chris Craft in my 1972 Hornet. It is the original engine and is in great running shape with strong compression. I have not had any issues with condensation, but have had issues with cooling even with a new water pump impeller. Mine has what I believe to be thermostats on both sides of the engine that I removed and tested for operation as they tend to wear out and lose their "Spring" for lack of a better term. I was told by my mechanic that they were tough to get. I am not really thrilled about the design of this cooling system. If anyone has any information on these, I would appreciate any help or comments. My engine, according to the Chris Craft manuals is supposed be rated at 320 hp.