need help whats wrong with my cooling system???

[stillhi33]

1985 mercrusier 170hp/470 i finally got the engine to run and notice the oil dipstick and hose hooked to the flame arester that it was pushing out or up fluids....could this be a head gasket problem ??? and i notice the heat exchanger was sizzling at the boot or the boot above the heat exchange i didn't know what to do so i cut off the engine....the engine has been sitting for 4 yrs but did ran 2 yrs ago just with the muffs on in the back yard could anyone help??is it the water pump that is wrong and wich one the front or back?????

 

[jerryjerry05]

Re: need help whats wrong with my cooling system???

Sounds like you need to check the oil level.The circulation pump doesn't usually go bad.It has a seal that will leak antifreeze when it goes bad.
If the boot?? was hot you weren't getting enough water thru the motor.
That's the impeller that went bad. If you got it that hot you need to really look things over.Jerry

 

[bruceb58]

Re: need help whats wrong with my cooling system???

There are many things that can be causing this.

Since you have the Merc 470, a leaky water pump can put water in your engine but that is among many other things including manifolds, cracked block and a bad head gasket.

 

[bruceb58]

Re: need help whats wrong with my cooling system???

The circulation pump doesn't usually go bad.

They sure do...especially on the Merc 470!

 

[bhammer]

Re: need help whats wrong with my cooling system???

Guys, the water pump does not go bad. There isn't even a pump so to speak. It is just an impeller bolted to the end of the cam, but no water pump or water pump bearings or any of that stuff that I see people say gooes bad with this engine.....


I am sure you are saying that it is the Cam Shaft seals though...
The cam shaft seals can leak becasue a groove is formed on the shaft from constant seal wear, but there are two of them, and a drain hole at the bottom of the timming cover. Unless the hole is plugged, there is NO WAY for AF to leak into the oil from this point. Now, if the aft seal was in backwards it could....

You are looking at another issue. Can tell if there was any antifreeze in the oil or was it just water. That will help us to narrow down your search. In a nutshell, the best way to find out what is leaking is to pressure test the system and listen for leaks.

The most common I have heard about: head gasket, power steering pump cooler and crackd head/block.

 

[Prop Buster]

Re: need help whats wrong with my cooling system???

I had constant overheating problems as well the past two seasons and checked and replaced many things......Earlier this season I decided to look at the "shutters" that are inside the cast iron exhaust pipe rights after the risers.......Wish I did that two years ago..........since I saw that my starboard side shutter was broken and cocked inside the pipe in such a way to block the exhaust and water flow to create a 50 degree temp difference than the port side.........

Now it runs as cool as it should..........

Just wanted to put that out there to check everything.
Oh yea, and don't belive any lazy mechanic that don't want to actively search for the problem........

Good Luck