Griff

I agree, it looks like the hoses are hooked up wrong.

Water exits the manifolds into the riser the same way as stock merc iron manifolds with holes between them.

Here's a pic of my old engine with Imco exhaust. My hoses are the reverse of yours.

BTW, those manifolds are not very new that he sold you. I would say at least 5-6 years. They changed the letering on the sides about that long ago.

Krumbsnatcher

mod image so you can see the hoses

mobilecal

uh oh.. Time to make another call. Sounds like a free rebuild......

GoCiggie31

Dave N,
thank you for the diagram. It looks like the hoses are switched. Dropped off boat at the shop today. Odd thing is that both sides are hooked up the same and only one side appeared cooked. Maybe the other side was on its way. I did notice a little more of a restriction kink in the bend of the hose on the side the manifold that fried.

Coin, . He built one motor and installed these new manifolds on both engines that I purchased from him, plus he does allot of go-fast stuff out here. . .yes gotta believe the repair shop will do the right thing I got faith in this guy keep ya all posted good or bad-wish me luck

GoCiggie31

Just wanted to close this thread out and keep ya all updated on what happened.

Manifold gasket burnt due to restricted flow(sticking thermo or check ball I think). So replaced manifold/gasket, pulled all the spark plugs, cranked out all the fresh water in the cylinders, douched with wd40, performed compression check, replace plugs and VAROOM, it started with no funny noises and idles as it did before along with pulling up to +5100 RPM... whew...boy do I feel lucky I did not bend a rod or ?. Just call me LUCKY.

Attached find the IMCO water hose routing recommendation FYI which recommends to remove the check valve(also different hose routing w/ IMCO applications vs Merc)

As always many thanks to you guys on OSO and Fred at Imco on the gaskets ++ and SUPPORT