high hours engine

(maxx_wake) · (maxx_wake) **Join Date: Sep 2003** 11-19-2006, 7:43 PM

I have a 90 SunSport with close to 1200 hours on a PCM 351. The engine runs great except for the fact that it takes about 5 or 10 minutes of fast idle at 2000 RPM to get it warmed up. It wont idle until after I do this. After it is warm though it runs great and starts on the first crank. Any idea? Time for a rebuild? Oh yeah, it also has a brand new carb installed about 3 months ago.

(wake_upppp) · (wake_upppp) **Join Date: Nov 2003** 11-19-2006, 7:57 PM

Slow warm-up: thermostat stuck open or removed? Won't idle when cold: choke not operational or not adjusted correctly? Time for a re-build? The best way to tell the condition of an engine: leak down test. If someone really knows what they're looking at, a vacuum guage hooked to manifold vacuum will also tell alot about engine condition.

(malibuboarder75)

Same thing on my 1983 2001 nautique and my friends' mastercraft stars and stripes. I have owned the boat for about 50-60 hours and haven't had any issues. The boat is really strong, but like you said takes a while to warm up. Once it is warm, you can turn it off and crank it no problem.

(wakesetter101) · (wakesetter101) **Join Date: Oct 2005** 11-20-2006, 5:07 AM

I would think it would be something less major than needing a rebuild if you say it runs fine when it is warm.

(malibuboarder75)

I think he meant the carb needs a rebuild, not the engine.

(biz) · (biz) **Join Date: Mar 2004** 11-20-2006, 6:25 AM

Choke adjustment maybe?

(maxx_wake) · (maxx_wake) **Join Date: Sep 2003** 11-20-2006, 9:50 AM

I have only had the boat for a few months but the previous owner had a brand new carb installed in June or July so I dont think it is the carb. He said that the boat would not idle at all and they had rebuilt the carb several times over the life of the boat so they went ahead and replaced it. Now, as long as I let it warm up first it runs like a champ. It is really not a problem other than haveing to sit on the ramp for a few minutes to let it warm up before I cut it loose from the trailer. I just wanted to make sure it wasnt a sign of bigger problems that I should try to get fixed over the winter. Other than the usual fluids/impeller change is there any special maintanence I should do to keep a high hours engine running?

(woohoo) · (woohoo) **Join Date: Jun 2006** 11-20-2006, 12:22 PM

Sounds like the choke if it's only when it's cold, I would try adjusting that.

(boss210) · (boss210) **Join Date: Jun 2006** 11-21-2006, 8:49 PM

choke adj, if it dosen't run rough when warm dont pull the motor.

(nbeihl) · (nbeihl) **Join Date: Mar 2004** 11-26-2006, 11:03 PM

carb for sure... I have had the same thing happen to me twice and both times a rebuild of the carb made it run like a dream!!!