do we have a resident expert on Mercruiser 3.7 and a alpha 1 gen 1

[Dodgy Diver]

just want to know if there is a way of testing it , I cant see circulation anywhere

I need to try to re weld the exhaust manifold as its leaking from a crack
then ill do a head gasket test

ive just got a feeling this engine has been run very hot before
the impeller was melted when I changed it

I really hope I can get this sorted

 

[madabouttheboat]

??? I was thinking of the v8 block all sea water cooled.

I had a V8 with FWC.

 

[spannerman]

It doesn’t matter whether it is FWC or seawater cooled all inboard engines have a circulation pump to move the water around the block etc.

 

[Mr Googler]

It doesn’t matter whether it is FWC or seawater cooled all inboard engines have a circulation pump to move the water around the block etc.

so…..the sea water cooled v8 say…..have an impeller in the leg and water pump on the engine? Didn’t know that ??

 

[Dodgy Diver]

well I believe I have a fudged manifold

so this is my thinking

I have taken off the manifold totally from the engine I have joined the aluminium water pot lets together ( I am assuming this is the engines cooling system side ) then the other end is cast iron , I am assuming this is the sea water end .

BUT and here is the Kicker

with the header tank connected to the garden hose , water comes out the manifold exhaust port at the end that exits the boat

im thinking internally the manifold has either a hole or at least a big crack.

 

[volvopaul]

Isuzu engine or Vauxhall corsa 1.7 tdi engine

 

[Dodgy Diver]

Mercruiser 3.7 470

Isuzu engine or Vauxhall corsa 1.7 tdi engine

Mercruiser 470. 3.7


thanks

 

[Dodgy Diver]

Mercruiser 1980 470 Exhaust Manifold Elbow and Reservoir #71527 | eBay

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