View Full Version : 1992 Prostar 205 Water in the Oil

07-17-2009, 05:55 PM
Hey guys,

Just bought this boat (unfortunately regretting that decision at this point) but it is what it is. To make a long story short, I had to have my mechanic replace the carb because the guy before us put a car carb on it (big no no, I know). But now, we went out today after a fresh oil change, trans flush and carb adjust, and spent about 30 minutes on the lake. Made 3 passes with friends skiing behind the boat, then all of a sudden a complete loss of power and very very hard to start. I would back off from full throttle and the engine would die without even idling. I noticed when we went out, I was only pushing about 35mph on the speedo with about 3500 RPM's.

Got it back to the dock, after only being able to go 20mph the whole way back (at full throttle). Pulled the dipstick to the engine oil and boom, milky white! Water all inside of the oil. I took it back to the mechanic and he came out to look at. We found on both manifolds, spots that had been epoxied. He is saying that the manifolds probably have a crack inside of them, allowing the water to enter into the oil.

Can anyone interject any more info for me? I just spend $7K on the boat and another $1K in maintenance and repairs. Now I have a 3000 pound anchor sitting in my yard.

The boat has 677 hours and the motor was supposedly a new crate motor from mastercraft with 30 hours on it. The guy I bought it from said they bought it in 2007 and only put 30 hours on it. It still had the break in oil in it when I took it to the shop.

Someone please help me. I am so frustrated and very disappointed. The summer is quickly passing by and my desires of skiing and boarding are fading fast. I do not have alot of $ to drop in this right now, so any advice would be greatly appreciated.



07-17-2009, 10:00 PM
First, which manifolds? Are you talking the exhaust manifolds? It's possible you could have milky oil from faulty exhaust manifolds, but rare. You could also have a faulty intake manifold allowing water in--more likely. I'd be praying its the manifolds and not the heads. Having been through milky oil 2xs with my old boat I know how frustrating it is. Unfortunately, your going to have to tear the top of that motor off to check the exhaust and intake manifolds and gaskets. Once you rule those out it could be a bad head or bad head gasket.

I'm not sure what your mechanical capability is. It isn't very difficult to remove the manifolds, but isn't fun either.

Good luck.

07-17-2009, 10:13 PM
Thanks, and yes, I was refering to the exhaust manifolds. They both have epoxy all over the back corners which makes me beleive they were cracked at one point. When the mechanic looked at it today, he said that he thinks when they cracked and epoxied them, they failed to check for an internal crack, which is causing it to ingest the water. I have a buddy that is going to look at them and try to determine if that is the problem. The more and more I look online, I am getting worried that it may be the head or the head gasket, but I am praying it isnt going to be! I have a guy about an hour away that has a parts boat, I think I may go try and get his spare motor, that way I have parts galore to go through.:(

Either way, looks like I am out for the summer, yet agian with no boat. No boat= No barefooting (6 years in a row is really starting to get old!):mad:

Anyways, if anyone else has any suggestions, please throw them my way. I am at a total loss for this and the wife is pissed that we just dropped that kind of money for an anchor!

Anyone have an extra repair manual for a 351 they want to give up? I am going to need all the help I can get with this project...

Trying to stay as positive as possible...


07-17-2009, 11:52 PM
PM me your email. I have the PCM manual, and some other various info on the 351. Where is Mountains in NC? I'm in Raleigh.

07-18-2009, 12:16 AM
I've bought and sold several boats, cars and jet skis.

NEVER be in a hurry to buy anything. Take at least a 30 minute test drive and try to make it do something wrong. ALMOST ALWAYS !! problems occur after the engine is warm.

When going to test drive an engine ask the people not to start it for several hours before you get there. Put your hand on the engine when you get there to test it is cold. This way you see and start it while it's cold. Run it for 30 minutes and get it hot. Turn it off, start again, do this several times. Recheck the fluids at start and finish of the test drive, this way you see the fluids hot and cold.

You only learn these things through the school of Hard Knocks. Luckily for you it wasn't a 25,000$ boat. You could put a new motor in it for a few thousand and have a great boat for 1500 more hours.

I hate to hear about people getting getting treated wrong.

Good Luck

07-18-2009, 07:31 AM
See if these downloads would be of any help to you...

PCM 302 and 351Engine Manual (http://correctcraftfan.com/Downloads/PCM%20Engine%20Owners%20Manual.pdf)http://correctcraftfan.com/reference/images/PCM_manual.jpg

PCM Engine Manual for all Fords and Chevys (1989) (http://correctcraftfan.com/Downloads/PCM%20Owners%20Manual_New.pdf)http://correctcraftfan.com/reference/images/PCM_manual_new.jpg

PCM Service Manual (http://correctcraftfan.com/Downloads/PCMsvcmanual.pdf)http://correctcraftfan.com/reference/images/PCMsvcmanual.jpg