350 mag mpi overheats only at idle

[silver_power]

I changed thermostat and as it was expected nothing changed. Let me ask something....as I just changed manifolds and risers, is it possible my mechanic to install the gaskets between risers and manifolds wrong? My engine is open cooling dry joint manifolds, so the gaskets must be positioned in such way that the hole at the front of the gasket where the hoses attached must be closed. If my mechanic installed them wrong, would be possible the engine to overheat at low rpms and not after 100 rpms? What would be the symptoms.?I do not want to disseamble them as I then will have to buy new one for installation.

 

[silver_power]

I ment 1300rpm, not 100 rpm. ....mistake

 

[alldodge]

The way I see it is there is not enough water going thru the motor. If the wrong gaskets were used and closed off the passage between manifold and riser, the riser would be cool, and the manifold would get very hot.

 

[silver_power]

This does not happen.....both risers and manifolds are hot...I can not think somethING else but a test in the water...

 

[silver_power]

Is it possible the cause of overheating at idle to be the fact that I use muffs without trim down the drive? I have the drive at the point that trim limit stop the up direction of the drive.....Just before trailering...I can not lower more while on muffs.

 

[thumpar]

The trim level wouldn't effect anything but running on muffs can. The impeller can pull more water than a lot of home water supplies can provide on a hose.

 

[Bt Doctur]

reversing the gasket will cause an over heat on a dry joint, I know, I did just that