coolant leak from front cover/water pump

vicsponjr

Petty Officer 2nd Class
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Aug 21, 2004
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Hi Guys, need some help. I'm really new to boats. <br />I had mt boat out yesterday, 85 Citation with a 3.7 merc 190 hp/alpha outdrive. Boat was running great, temp around 170 degrees for at least an hour or so. When we slowed down I noticed coolant smell/steam. I looked things overand noticed coolant dripping out of the front cover, or water pump. I know on a car this means replace the water pump. I read here that the seals on the timing cove are cutting into the camshaft? is this correct? It seamed to happen all of a sudden, loosing a lot of coolant fast. i'm thinking that if it were the seals cutting the cam it would be a gradual problem.Could it just be that the water pump went bad?
 

tommays

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Jul 4, 2004
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Re: coolant leak from front cover/water pump

i think you mixing up two different things if the water pump is leaking it really has nothing to do with anything else <br /><br />a water pump is and easy DIY job just be sure you buy a good marine water pump and new gaskets<br /><br />tommays
 

vicsponjr

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Aug 21, 2004
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Re: coolant leak from front cover/water pump

That was what I'm hoping, just the water pump. When I searched the posts I read that it might be the t/c seals.
 

Don S

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Re: coolant leak from front cover/water pump

EDIT: Oops, disregard, I read his post as a 5.7, not the 3.7L engine......completely different.
 

Bt Doctur

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Aug 29, 2004
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19,345
Re: coolant leak from front cover/water pump

On these motors there is no sep. water pump. circulation is from an impeller mounted on the end of the cam.looking at the motor ,if the leak is lower left near the cover pan area suspect the 2 seals in the cover.one seals the oil, the outer one seals the A/F side.visable A/F is an indication of seal failure either from a worn seal or a groove cut into the camshaft end.
 

tommays

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Re: coolant leak from front cover/water pump

read your link my bad sorry<br /><br />tommays
 

vicsponjr

Petty Officer 2nd Class
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Aug 21, 2004
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Re: coolant leak from front cover/water pump

OK. So I can set my sights on just the seals being bad and no grooves on the cam (i hope). Now does anyone have a link on how to remove the front cover? I looked on mercstuff.com but couldn't find anything.
 

Don S

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Re: coolant leak from front cover/water pump

You will need to order the service manual from Mercruiser. It's manual #8 and the PN for the manual is 90-44553.<br />The 470 style engine was only used by Merc from 85 to 89, and no one else manufactured them, it was strictly a Mercruiser engine.<br />But if you are going to be working on your own engine, it will be a very handy TOOL to your toolbox.
 

vicsponjr

Petty Officer 2nd Class
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Aug 21, 2004
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174
Re: coolant leak from front cover/water pump

You got to wonder why they didn't make the water pump a part easier to replace, like that on a car engine.
 

delsol

Senior Chief Petty Officer
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May 27, 2002
Messages
749
Re: coolant leak from front cover/water pump

i always think they make it difficult on purpose.<br />take your time you can fix it
 

vicsponjr

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Re: coolant leak from front cover/water pump

thanks don, bob. A guy a work has a puller for the balancer and has done this job before. He said he'll give me a hand if i run into trouble. I just don't want to screw up the charging system, it looks expensive to replace.<br />Do you need any special tools to replace the balancer? I can't get a manual till tomorrow when the marine store is open.
 

Bt Doctur

Supreme Mariner
Joined
Aug 29, 2004
Messages
19,345
Re: coolant leak from front cover/water pump

Just a longer threaded stud to start drawing the balancer back on untill there are enough threads to install the original bolt.<br />DO NOT HAMMER BACK ON .youll destroy the magnets
 

vicsponjr

Petty Officer 2nd Class
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Aug 21, 2004
Messages
174
Re: coolant leak from front cover/water pump

I got my parts together and I am going tomorrow morning to pick up the boat from the marina. I didn't get any repair sleeves for the camshaft, hoping that it isn't the problem, although I looked at a couple of used cams at work (engine plant) and I saw where they wear. A friend suggested not installing the seal back in the exact spot, so the seal would ride in another location on the shaft?? Anyone ever try this? I read somewhere that the sleeves are $40 each, and need special tool. Anyone know where to get them at a more reasonable price? I bought a manual, Seloc, not much detail on the repair.
 

tommays

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Jul 4, 2004
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Re: coolant leak from front cover/water pump

i use the sleeves on machinery and they are great but they are only about a .005 wall and each size needs a tool or it is toast on the install <br /><br />the sleeve will outlast the motor and save you haveing to go back in again<br /><br />tommays
 

vicsponjr

Petty Officer 2nd Class
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Re: coolant leak from front cover/water pump

Does anyone know what size diameter the camshaft nose is?? I forgot to bring home a micrometer. :(
 

delsol

Senior Chief Petty Officer
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Re: coolant leak from front cover/water pump

you work in an engine plant and forgot your tools
 

vicsponjr

Petty Officer 2nd Class
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Re: coolant leak from front cover/water pump

Problem. I made the repair as instructed and it is still leaking out of weep hole but not like before. I pulled it apart again and as far as i can see the seal is riding on the sleeve. The back of the seal (facing inside of engine) looked like it got hung up on the sleeve when i was putting the cover on. It doesn't look dammaged but.......... I also looked for cracks in the cover but didn't see anything. Does anyone have any suggestions????
 

delsol

Senior Chief Petty Officer
Joined
May 27, 2002
Messages
749
Re: coolant leak from front cover/water pump

you sure you did not damage seal
 
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