Installing heat exchanger

kvkon

Seaman
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Aug 6, 2006
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64
I have a 2004 4.3 MPI/Alpha 1, raw water cooled, single point drain. I have a heat exchanger I want to install (engine only). Would anyone have a flow diagram for the current setup? Anyone done this install? Tips? Thanks!
 

achris

More fish than mountain goat
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May 19, 2004
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2004, too late. Heat exchanger needs to go on with less that 10 hours or 6 months in salt... You'll cause more problems than you'll solve by closing the cooling system now.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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if you had a fresh water only motor, then you have a chance to use a HX. otherwise after 14 years, it wont help a bit
 

kvkon

Seaman
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Aug 6, 2006
Messages
64
Fresh water until this year. Has less than 10 hours total salt time and drained and flushed after each salt water dip. I'll pull the thermostat housing and see what it looks like. Thoughts? Another question, if I run it this way until the salt eats it and then build another one with HX installed what do I need to look for in a block? Will the correct casting number give me all the mounting points and connections I need?
 

achris

More fish than mountain goat
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...Another question, if I run it this way until the salt eats it and then build another one with HX installed ...

That is going to take quite a few years... Saltwater engines are generally good for 20 to 30 years, as a minimum.... Or until the elbows rot (because they are not being inspected regularly :facepalm:) and take the engine out.

Chris......
 

kvkon

Seaman
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Aug 6, 2006
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Wow, OK I'll just run it as is. I wasn't aware I could get that kind of life out of a raw water cooled engine. Thanks all!
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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your exhaust elbows will only last about 5 years. your manifolds may last 10. the block and heads with proper maintenance will last another 20-30 as Chris stated

however every few years you need to pull the elbows and inspect. when the elbows go, they leak water into the motor which kills the motor.

also, your impeller wont last as long in salt.
 

kvkon

Seaman
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Aug 6, 2006
Messages
64
Thanks, excellent info. I have the dry joint elbows. Any thoughts on them vs old design?
 

achris

More fish than mountain goat
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May 19, 2004
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27,468
Yeah. They're great! Takes away the weak point in that old design. I'm on my second pair of elbows, the first lasted 8 years...
 
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