Leaking Antifreeze?

[JoChek219]

Hi, I have an 87' 3.7L Mercruiser (470) with an A1 drive and I'm bringing it out of storage and guy at marina said I was good to go,..... Brought boat home and checked everything before start up, lowered drive and noticed some anitfreeze dripping, I looked and the aintifreeze was completely emtpy, so I thought maybe it was just left over from winterization that was leaking.... Bought a gallon of antifreeze and it did the same thing leaking out of outdrive... I have no idea why . I'm assuming he forgot to put a plug in somewheres....any help would be greatyly appreciated , hope to go out this holiday weekend

 

[Reel Poor]

Re: Leaking Antifreeze?

If it's dripping out of the drive it has to be getting into the exhaust manifold.

 

[jearl]

Re: Leaking Antifreeze?

I'm not anywhere near the most experienced but assuming you must have a closed cooing system check the gaskets between the exhaust manifolds and risers. Hopefully just the gaskets and not a crack in either. not sure if the water level would come up high enough or where its leaking out your outdrive, exhaust or fresh water pick up? if leaking from pick up maybe you have a leak in your heat exchanger itself. I'm sure someone more knowlegeable will reply so stand by for feedback and good luck! Jim

 

[JoChek219]

Re: Leaking Antifreeze?

ok thanks for the suggestions! Yes its a closed cooling system. Is this a hard thing to do to get to to check the gasket?

 

[Haut Medoc]

Re: Leaking Antifreeze?

No, it is not.....
Check the mating surfaces between the riser & manifold.....
Pressure test the manifold.....
Pressure test the heat exchanger.....​

 

[JoChek219]

Re: Leaking Antifreeze?

when taking off the exhaust manifold, should I heat it up to loosen any gasket material or just use a rubber mallot or a piece wood??

 

[JoChek219]

Re: Leaking Antifreeze?

update:
I pulled off the Exhaust elbow resevoir and noticed there is a hole where the rubber boot connects to the upper exhaust elbow assembly..... As I took it apart I noticed a stain on the elbow assembly, could that be why I lost all of my antifreeze or is that just exhaust water that leaked out the hole down the elbow?

Curious if I need to keep looking and try to take off the exhaust manifold to check our that gasket.....what should you use to get the manifold off the block... wood, rubber mallot, wd 40 or something on the studs to help free it up??

All help is greatly appreciated

 

[Coors]

Re: Leaking Antifreeze?

a hole is not good; slap it off with your hand, it is not stuck that hard.

 

[JoChek219]

Re: Leaking Antifreeze? UPDATE

Re: Leaking Antifreeze? UPDATE

well that hole in the reservoir/exhaust elbow i'm told is molded that way, anyways took the manifold off and the gasket and the gasket seems fine, So I guess I'm going to have to press. test that somehow and see what happens...and if that turns out fine next is the heat exchanger....


Just shocked how quickly the gallon of antifreeze went straight thru and out the outdrive.... I"ll post my results....thanks for the advice and if you can think of anything else that would be greatly appreciated