back flush 1978 140 A

I picked up this old bayliner , went to replace the water pump impeller and found the old one to be missing every fin. I found only maybe one complete fin , if that. This means the rest is in the system and I am stumped as to haw to retrieve the rest out of the system. My system has the closed cooling with antifreeze. Also the impeller shaft is quite loose, is this normal ?Thanks in advance

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bayliner1957 said:

I picked up this old bayliner , went to replace the water pump impeller and found the old one to be missing every fin. I found only maybe one complete fin , if that. This means the rest is in the system
Yes, and these pieces must be retrieved. If not, you will have over-heating issues again.

and I am stumped as to haw to retrieve the rest out of the system.
You will need to disassemble all of the components that are down-stream from the seawater pump.
Find all of the broken pieces that you able to, and then perform some good forensic science by trying to layout and re-assemble the damaged impeller.

My system has the closed cooling with antifreeze.
Yes, all of the Volvo Penta OHC 4 bangers are fit with Closed Cooling systems.

Also the impeller shaft is quite loose, is this normal?
NO!

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Continued:

Find the reason why the impeller became damaged.

Short of starting the engine up without a water supply, the first suspect may be the water neck fitting.
These water neck fittings are wear items and must be routinely replaced.
Note the special beaded gasket that installs underneath it.

Second suspect may be the upper pivot tube bushing. If this bushing is worn and creates slop, the beaded gasket will not seal correctly.

Third suspect may be the lower pivot tube O-ring seal.



By the way..... back-flushing may not push all of the impeller fragments out.
Unfortunately, there will be no short cuts!
Take everything apart, find all of the pieces, and you won't need to worry during your next outings.

I don't know about the 140A being that it is fresh water cooled, but my raw water cooled 130C has the water-fed oil cooler immediately after the water pump and the oil cooler will not let anything bigger than about 1/8" in diameter to pass through it. I got lucky recently when my impeller shredded and I found the one missing impeller piece in the front side of the oil cooler.

am_dew said:

I don't know about the 140A being that it is fresh water cooled, but my raw water cooled 130C has the water-fed oil cooler immediately after the water pump and the oil cooler will not let anything bigger than about 1/8" in diameter to pass through it. I got lucky recently when my impeller shredded and I found the one missing impeller piece in the front side of the oil cooler.

Click to expand...

All of the Volvo Penta OHC 4 cylinder engines were OEM with a Closed Cooling System!

Aluminum cylinder head on top of a cast-iron cylinder block!




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