4.3L Mercruiser Leak?

[SWFLBoater]

Hi all, I'm a fairly new boater, but have a little experience. Ive browsed these forums before but just recently became a member. Hopefully I can contribute to it some. I recently bought a Blue Water Blazer 16 foot bow rider with a 4.3L Mercruiser. They are both circa 1994. The boat to begin with had no problems started right up every time, and ran fine. Didn't take on any water and overall was a great boat for my wife, my son, and myself. Recently though I was taking it out with a friend of mine and the starter wouldn't crank the engine. I know a fair bit about cars so I know a few taps sometimes will get the starter cranking...... 1 1/2 hours later I finally got it to turn over after some coaxing of the starter. The problem is right behind the starter, there is a small slit in the housing (One's that looks like it is suppose to be there, not a defect) that water is pumping out of when my engine is running. If I increase the throttle to 3k or so it pretty much stops, and all but stops if im traveling. Idling is when its the worst by far. I'm not sure whats going on. I just need a jumping off point. I'm a do it yourself type and want to try and tackle it myself if at all possible. AKA I'm cheap and want to fix it without paying someone else if I can haha. Any help or advice would be greatly appreciated. Can take and upload pictures if needed. I have a new starter ready to install once I figure out what this other issue is.

 

[Bondo]

Re: 4.3L Mercruiser Leak?

Ayuh,.. Welcome Aboard,.... use a few Paragraphs, your post is Hard to read...

My WAGuess is, there's been Water in the bilge, high enough to flood the flywheel cover...
The water is getting into the starter,+ the flywheel is splashing it around...

Pull the Starter,+ the little tin cover you'll see down there,.. That'll drain the water...

 

[SWFLBoater]

Re: 4.3L Mercruiser Leak?

Thanks, ill give it a shot and see if that works. I thought at first that was what was happening too, but the amount of water coming in worries me.

I ran it for probably an hour or so and the water didn't seem to slow down or come in slower.

Ive got the starter off already awaiting the new one ill give your suggestion a shot and see how it goes. Thanks.

 

[Bondo]

Re: 4.3L Mercruiser Leak?

but the amount of water coming in worries me.

Ayuh,... I suppose it could be a popped Coreplug,...
I think there's a couple of 'em behind the flywheel...

 

[achris]

Re: 4.3L Mercruiser Leak?

If I was a WAguessing man.... I'd be guessing hole in the bellows. .
The hinge pins on the gimbal ring in that era were a few millimetres too long, and the end of the pin protruded enough to wear the bellows just at that point. Every time the drive was swung to full lock the end of the pin rubbed the bellows.

Turn the steering wheel full one way, have a look in at the bellows and see if you can see any problems (holes and splits are problems), now swing the wheel full the other way and check the other side....

If water is getting into the bellows it then leaks into the boat... I think the reason it stops once you reach about 3000 revs is because you're up on the plane and the bellows are out of the water....

Just my thoughts,

Chris......

 

[Don S]

Re: 4.3L Mercruiser Leak?

I doubt it's long hinge pins, (never heard of that one myself), causing your problem, but I would bet it's probably the original ujoint and shift cable bellows. They are probably just dead. They should be replaced as a regular preventive mainenance items about every 5 years. Are you also getting a growling noise from behind the engine? Probably from water in the bearings making them rusty and noisy.
Pull the drive and have a look inside the bellows.