Merc 470 Exhaust Manifold Test

[cshirley]

I have this manifold, does anyone know how you'd go about testing it? My coolant is flowing out of the exhaust at a pretty rapid rate (like big hole somewhere and not a crack and bad gasket).

http://marineengineparts.com/shopsite_sc/store/html/product721.html

I see 3 ports where the riser goes up and water flows out all 3 and into the riser, should the coolant flow through the riser and then back into the engine while the seawater flows through the riser and out the exhaust?

Trying to determine if the problem is the manifold or riser.

Thanks.

Curtis

 

[bhammer]

Re: Merc 470 Exhaust Manifold Test

Need to check your heat exchanger for a leak as well. Very common place to find leaks and would loose coolant. Here is hte page from the 470 manual.

 

[cshirley]

Re: Merc 470 Exhaust Manifold Test

Sorry forgot to post that but I already checked the heat exchanger and its fine. I can literally put a hose in the reservoir and it turn it all the way on and watch the water pour out the exhaust on the back of the boat.

I'm about to pick up another 470 for cheap that has an upgraded aluminum manifold but I've read that it won't work on mine as mine is the earlier version. Anyone know any truth to that?

By the way, Fort Worth, very nice place. I have family in Carollton, lots of very nice homes up that way!

Thanks!

Curtis