1988 mercruiser 4.3l overheating

hit4thefence

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I have a 1988 mercruiser 4.3l engine (Alpha). Im planning to video the problem in hand. It runs fine but when facing the engine the hose off the left side of the water pump starts to boil water inside and expands.Its boiling from the lower end of the hose. Everything is brand new parts for the engine also the engine is new. Any ideas?
 

hit4thefence

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Feb 26, 2012
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Re: 1988 mercruiser 4.3l overheating

I have a 1988 mercruiser 4.3l engine (Alpha). Im planning to video the problem in hand. It runs fine but when facing the engine the hose off the left side of the water pump starts to boil water inside and expands.Its boiling from the lower end of the hose. Everything is brand new parts for the engine also the engine is new. Any ideas?

Bump
 

Bondo

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Re: 1988 mercruiser 4.3l overheating

I have a 1988 mercruiser 4.3l engine (Alpha). Im planning to video the problem in hand. It runs fine but when facing the engine the hose off the left side of the water pump starts to boil water inside and expands.Its boiling from the lower end of the hose. Everything is brand new parts for the engine also the engine is new. Any ideas?

Ayuh,.... Was the raw water pump rebuilt,..??
 

Bondo

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Re: 1988 mercruiser 4.3l overheating

I purchased a brand new standard water pump.

Ayuh,... The 1 on the front of the motor,..??..??

The Raw Water Pump, is in the lower unit, 'n has a Rubber impeller...

Changin' it is an Annual, or Semi-annual thing that's gotta be done... Maintenance....

Are ya supplin' water, with muffs when ya run it on the wagon,..??
 

hit4thefence

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Feb 26, 2012
Messages
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Re: 1988 mercruiser 4.3l overheating

Ayuh,... The 1 on the front of the motor,..??..??

The Raw Water Pump, is in the lower unit, 'n has a Rubber impeller...

Changin' it is an Annual, or Semi-annual thing that's gotta be done... Maintenance....

Are ya supplin' water, with muffs when ya run it on the wagon,..??

Both impeller and front side engine pump are new. I just dropped lower unit yesterday and impeller is still solid. Yes I'm using hose muffs.
 

hit4thefence

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Joined
Feb 26, 2012
Messages
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Re: 1988 mercruiser 4.3l overheating

Both impeller and front side engine pump are new. I just dropped lower unit yesterday and impeller is still solid. Yes I'm using hose muffs.

Bump.

Still trying to figure this out if anyone can help. I am currently not at home so couldn't make video. It's just overheatining lower left side hose.then boiling the water. It's like something isn't opening.
 
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