Apparenlty I've bought a lemon (470) Help!

slydog75

Petty Officer 3rd Class
Joined
Jun 15, 2009
Messages
90
Well, i bought my first boat yesterday, then today I found this forum. It appears I should have done that the other way around! I bought a 1987 Wellcraft Classic 190 with the Mercruiser 3.7L in it. I posted all excited on the general disccusion area and found out that this engine isn't exactly well liked. I knew when I bought the boat that the engine had a small coolant leak but the previous owner figured it was just a gasket and I figured we could change those out pretty easy. Turns out that these engines are apparently infamous for developing a coolant leak around the camshaft seal.



One good bit of news (I think) is that is has an alternator instead of a stator. Could this have been a factory option from Wellcraft or would this have been changed out at some point by a previous owner?

Fortunately I am somewhat mechanicallly inclined (I've done complete rebuilds on a couple bike engines and a Volkswagen beetle engine) so hopefully I can handle this work myself to keep costs down.

So, since I doubt the previous owner is going to give me my money back, I better start finding out all I can about this motor and what it's going to take to fix the leak and keep it running in top shape. Where should I start looking? So far I've been given this article (which is how I first found out that most of these motors don't have alternators): http://www.sterndrives.com/470information/470coolantleakrepair.html
 

sea wolf

Lieutenant Junior Grade
Joined
Apr 3, 2002
Messages
1,219
Re: Apparenlty I've bought a lemon (470) Help!

Do a search here & I'm sure you'll find plenty of info for your setup. If it's any consolation, Wellcraft is a well made, sound boat. Good luck.
 

ultrasport

Cadet
Joined
Oct 13, 2008
Messages
28
Re: Apparenlty I've bought a lemon (470) Help!

I also am losing antifreeze which I believe is getting into my motor. Oil looks clean but have sludge looking blow by getting into my flame arrestor. I have already completly rebuilt this motor twice in 3 years. If I have the same prob with the cam shaft im gonna sink this boat. Any way to figure out where leak is coming exactly from. Would really not be happy if I gotta pull this motor again. Was thinking maybe from head gasket or in take manifold but these gaskets are only 6 months old. Help needed please.
 

cooter2506

Senior Chief Petty Officer
Joined
Apr 8, 2007
Messages
733
Re: Apparenlty I've bought a lemon (470) Help!

Ultrasport please start your own thread so we can help you better ad not confuse you and the OP.
 

slydog75

Petty Officer 3rd Class
Joined
Jun 15, 2009
Messages
90
Re: Apparenlty I've bought a lemon (470) Help!

Bubba, thanks for the reply. I spoke some more with the previous owner and he says he recently rebuilt the motor (about 20 hours ago) and that the leak isn't in the right place for it to be the camshaft seal. He thinks is the manifold gasket which should be a lot easier to fix. I'm hoping that does the trick.
I'm really nervous now since I've never seen EVERYONE on a forum agree about ANYTHING, but not one person has jumped in to really defend the 470. That's bad! If it gets to bad, is there a replacement motor I can put into this boat easily?

Also, The PO suggested I add some sort of coolant system stop leak if I wanted to try running it the rest of this season before changing the gaskets. I do want to attempt to run it as is the rest of the season, assuming the leak doesn't get worse, but I'm not sure about adding a product like this. Thoughts? he mentioned something called BG's but I can't 'find anything about it online.
 

stonyloam

Vice Admiral
Joined
Mar 13, 2009
Messages
5,827
Re: Apparenlty I've bought a lemon (470) Help!

Since you asked, I'll defend it. My 470 is 22 years old and still runs strong. Yes I replaced the cam seals and the voltage regulator, but if yours was properly rebuilt it should give you lots of years of fine service. If you want to feel better about your 470, just do a site search for "cracked block" on this forum. the ol 470 don't look so bad then. Good luck, have fun, and don't worry about it too much.
 

slydog75

Petty Officer 3rd Class
Joined
Jun 15, 2009
Messages
90
Re: Apparenlty I've bought a lemon (470) Help!

Since you asked, I'll defend it. My 470 is 22 years old and still runs strong. Yes I replaced the cam seals and the voltage regulator, but if yours was properly rebuilt it should give you lots of years of fine service. If you want to feel better about your 470, just do a site search for "cracked block" on this forum. the ol 470 don't look so bad then. Good luck, have fun, and don't worry about it too much.

Thank you! That does make me feel better!
 

slydog75

Petty Officer 3rd Class
Joined
Jun 15, 2009
Messages
90
Re: Apparenlty I've bought a lemon (470) Help!

I'm going to be taking my new boat out on the water for the first time this afternoon. I think I know most things I need to know but one question I still have is what should the max temperature be before I should start worrying that it's overheating or something? I"m not sure if mine has the 3 or 4" heat exchanger, how can I find that out?
 

Rocky_Road

Lieutenant Commander
Joined
Oct 8, 2008
Messages
1,798
Re: Apparenlty I've bought a lemon (470) Help!

I'm going to be taking my new boat out on the water for the first time this afternoon. I think I know most things I need to know but one question I still have is what should the max temperature be before I should start worrying that it's overheating or something? I"m not sure if mine has the 3 or 4" heat exchanger, how can I find that out?

Here is a picture of a 3" heat exchanger...the 4" looks the same, only larger in diameter. The heat exchanger resides on the port side of the engine, underneath the exhaust manifold:

2j31itt.jpg


It is not uncommon for there to be a pin hole leak inside the exchanger...the antifreeze leaks into the sea water, and exits the engine through the exhaust. There would be no visible signs of antifreeze in the engine bay. Any decent radiator shop can pressure test...and repair...a heat exchanger.
 

stonyloam

Vice Admiral
Joined
Mar 13, 2009
Messages
5,827
Re: Apparenlty I've bought a lemon (470) Help!

There seems to bee a little confusion as to exactly what is leaking. Take a look at the circulating pump on the front of the engine (where the big hose comes out). from the top left hand bolt (as you face the engine) count down (counterclockwise) three bolts, and you should see a tiny (1mm) hole between the third and fourth bolt. That is the weep hole to drain antifreeze that gets past the water seal. That is the ONLY place you can see leakage from bad cam seals. Start the engine, and if antifreeze does not come out of that hole, your cam seals are NOT I repeat NOT the problem.
 

rocket1968

Petty Officer 2nd Class
Joined
Feb 18, 2008
Messages
125
Tough call on the stop leak...i have used it successfully

Tough call on the stop leak...i have used it successfully

Yes, these products do work and should at best be a temporary fix if you want to possibly extend the life of an engine that you dont feel is worth the repair time or cost. I had a head gasket leak in the front of an older explorer and followed the instructions exactly as stated. This involved flushing the system after running the leak stop product. The truck (which is my beater and secondary tow mule) has gone an additional 12K miles and I will be using it to tow the boat this year. I am not sure you will have the same result in a boat but at least one persons perspective.
 
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