2008 mercruiser 5.0 alpha1 gen2 overheating

[rvguy1]

just bought this boat and cant use it. replaced thermostat and impeller, getting water into block and elbows, still overheating even if I take the thermostat out. like the water is stuck inside block and not going out the exhaust, but you can see it coming out of the pipes, however, nothing coming out of bellows. desperately need help

 

[Lightwin 3]

What shape was the old impeller in? All the blades still there? If not, one or more are probbably in the water passages.

A previous impeller service may have left something in there.

I would start by removing hoses and flushing with the muffs, engine OFF. A little messy but it's just water.

 

[rvguy1]

old impeller looked good, all blades there, seems like plenty of flow coming in also, pulled one riser and elbow last night and cleaned, not sure how clogged it was because a bunch of rust fell off when I removed it. also someone else has taken them off before and installed with steel plates and permatex, no gaskets, but there weren't any signs of water intrusion in the manifolds. question. should water also come out of the bellows?

 

[rvguy1]

by the way, these are dry risers and elbows with semi restrictor gaskets (big hole on one end and pin hole on other)

 

[alldodge]

What's your serial number?
Is this a 1, 2 or 7 point drain system?

 

[Bt Doctur]

you got the gaskets reversed