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Adding Flush Port/Fitting

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Luciano

New member
Hi there,
I first want to say that the amount of great information provided on here is just amazing, i am new to this forum, have done lots of reading and learning so far.

I have a 1993 v6 volvo penta engine, model is 431B, i live in canada, and am trying to figure out if i can add a "tee" to the inlet of my raw water pump so i can run antifreeze thru my engine for the winter months.

I have test the muff on the lower unit and they leak alot, i dont want to a: waste good anti freeze and b: dont want / minimize amount of antifreeze going into the enviroment.

Thanks alot

Luciano
 
Luciano, I'd strongly suggest that you NOT DO THIS! At least not with the intension that this will protect your Raw Water cooled engine without draining it afterwards!

There is a very high risk of giving ourselves the "False-Positive" when we see anti-freeze coming from our exhaust system.




What is often not considered is:
  • Dilution from existing raw water within the engine block.
  • The thermostat NOT opening enough to give a Full Exchange of Anti-Freeze for raw water (this is the important one!)
  • Most sea water (aka water being introduced via the muffs or your "T" fitting, for example) goes right on through, and out the exhaust. The engine does not receive the anti-freeze until the "Warm" thermostat releases it as temperature dictates. Think of this as an "As-Needed" or "On-Demand" basis!
Everything will seem to be just fine in November.
Come April or May is when we discover that we did not do this correctly!

Best to follow your engine specific OEM manual re; the correct winterizing procedure!

Just plain Air will NEVER freeze and expand causing engine damge!

.
 
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I understand exactly what you are saying, however, i failed to mention that my plan was/is to run boat on muff until at operating temp then run the anti freeze. or do you think this is still to risky?

Thanks for the reply.
 
Luciano said:
I understand exactly what you are saying, however, i failed to mention that my plan was/is to run boat on muff until at operating temp then run the anti freeze. or do you think this is still to risky?
Click to expand...
My 40+ years as a mechanic says YES!
It is the dilution that we have little control over, unless you were to take extreme measures!

IMO, there is no reason to do this if you drain the block/heads/exhaust after a good fresh water flush.

If you want the "feel good" feeling of anti-freeze inside of the engine block, then remove the temp sender, or the thermostat, and pour the stuff in this way. Likewise with the exhaust via the cooling water hoses!
I'd recommend that we always drain this again afterwards!

Like said:
Everything will seem to be just fine in November.
Come April or May is when we discover that we did not do this correctly!
 
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Just drain everything. Don't leave any water or coolant in the engine at all. Change the oil with fresh and put the boat to sleep.
 
I have 89 Baretta with aq131d, 4 cly. I removed the inlet water hose at the outdrive ( volvo 275 ), put an extension on it, and stuck it in three gallons of full strength antifreeze after the engine was warmed up. It sucked it up, and exhausted it thru the outdrive. Do you feel I should still drain the block ? Also, what is the procedure ?
I have the volvo shop manual, it's not mentioned it in. Also, looked around on the forums for the correct procedure . By the way, the muffs worked terrible on this drive, so I went to Lowes and bought a 30 gallon tote for around ten bucks, filled it 3/4 with water, and lowered the outdrive into it. Worked great .
Thanks,
Dale
 
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