Engine Replacement

[waybomb]

Have you checked the pcv valve on that engine?

[Viper]

I agree with the guys suggesting further testing, and definitely check you PCV valve. While it's common for this to be a lower end issue, it could just be an upper end problem that can be easily resolved without removing the engine but work on just the heads. I agree compression and leakdown tests are where you should begin, then go from there based on findings, they won't however tell you if oil is leaking past the valve seals in the heads. If the leakdown test indicates a lower end issue like worn piston rings, then you have your answer regardless whether the valve seals are bad or not, the engine will have to come out anyway.

A couple of questions:
Is there a lot of blue smoke when you first start her up after sitting overnight and then it subsides?
Does the blue smoke continue for as long as you run the engine or just at startup?
Is there blue smoke regardless whether it's at 800 or 2000 RPM?
Are you noticing a performance issue; rough idle, etc,?
Most important; have you had an oil change recently, was the proper grade oil used, AND is your engine oil at the proper lever?

As for the number of hours, while they're a starting point, the only thing it tells you is how long the ignition system has been energized. On older engines some of that could be from just leaving the ignition key in the ON/RUN position. Do that when you leave to go home for the week and you've added over 100 hours. What's more important is how the engine was run and maintained in the past. A very high hour engine that was well maintained and not overworked will be in best condition than a low hour engine that's been neglected and abused. The above tests with the addition of a vacuum test (if you can still find someone who knows how to interpret it) will tell you more about the engine's condition than the hour meter will.

I wouldn't repower the boat with lower horse power engines.

Is this a fresh or salt water boat? Has she ever been in salt water? You should add your location to your personal info, it helps.

[waybomb]

Also, if it is valve stem seals, it can be done in-boat without removing the heads.
I haven't done it in a boat, but did on many car engines back in the day. It's not hard at all.

[bud37]

Just to add....Valve seals can be an issue when they get old and lose their elasticity, but on a high hour engine the chances of the valve guides being worn and causing the seal issue can be more likely. New seals may possibly work for a while....it is easy enough.

Let's see what the compression tests bring, I agree with the leak down, that would be my choice of diagnosis.

The pcv valve check is good as a bad one can cause pressure issues, they are cheap enough , but it is important to get the right one for the engine.

[Cooler]

Ditto to all info above, especially Viper list. 1100 hrs on Crusader engines is not high engine hours, unless they were beat to heck during that time. Before you consider engine change, I would try to contact previous owner to find out how he ran them, and who maintained them. I am thinking this oil burn is going to be something minor. Did you check oil level to determine the rate of oil burn? 350XL's were the bread & butter engines for Carver. I assume you are carburated, because FI would be the 350XLi's. Maybe the carb is just set to a rich mix. Good luck! er

[Capt Happy]

Thanks all for responding. I will try and cover the above questions. We are located in Nova Scotia, Lunenburg to be exact. Will update profile. Engines from '97 up until 2015 were soley fresh water (Great Lakes). We purchased the boat and had it transported to the East Coast, since then, salt water usage. There were approximately 740 hrs when bought, currently sitting at 1189 and 1186. We have always maintained and upgraded as needed. I can only go by the previous owner's statement that he properly serviced the engine's. Ten years later and we still maintain contact, so have no reason to doubt his word. I believe he is a very honest gentleman. He has and continues to be very helpful when any questions concerning the vessel comes up.

The blue smoke is worse at startup and dissipates somewhat during operation, although it never completely goes away. Engine rpm does not seem to make it worse, but remains present during all variations of speed.

I always check the levels of fluids before running. We have been using the recommended oil for these engines and change at least once a season. Our current usage averages about 50+ hrs per year.

There have been some instances of rpm deviations with the st'bd engines as noted on the sync gauge, coupled with rough performance. This might last a few minutes and then correct itself for hours. Never seems to act up when mechanic onboard of course. This seems to be more prevalent at higher rpms.

Another item to add, is the engines are fuel injected, I may have mislabeled them, my bad.

We have maintained the engine's to the best of our ability and they are hardly ever pushed beyond 2100, except in rare cases other than to clean things out for a few minutes.

We will do all the suggested tests and report back as soon as it bloody warms up here a bit. Once again, thanks to all the great members of this forum. It is very nice to be able to request information from many knowledge folks.

Cheers, Capt Happy

[MyPleasure]

Hi, just my opinion of course, but you should be able to get 2-3000 hours from a properly maintained gas engine as long as it hasn’t been abused. Our old Uniflite had 350 cu in Crusaders, and that boat now has 2000 hrs on the engines and still running great, no smoking or excessive oil consumption.

[Cooler]

You may want to consider fuel injector inspection. You may have one or two gummed up. Have you ever used ethanol gas? Your symptoms sound similar to a friend of mine, on Mercruisers. Took a while to narrow down to bad injectors. But he had one side rebuilt, and the problem was solved. er