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New engine not cooling off muffs

T

twinflyer

New member
Just rebuilt 5.7GL Volvo Penta. It will not pull water on the lake. Not enough anyhow. So far I tried a new aftermarket impeller. No change. I just taped up the inlet veins on the foot and put water in the hose just behind the power steering cooler. The only place water is leaking from is one of the 4 small holes on the SX-M drive. New pump on order but is this water coming out the small hole an issue? Also see attached pic of old pump housing. Thanks in advance
 
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Are you sure you did not reverse the in and out hoses? ALSO, notoriously, for Volvo pumps, there are different impellers available that are very slightly different in size... ONLY the exact one will work. Owned/maintained boats for over 50 years and have learned to not use aftermarket rubber goods.
 
Not sure which pump they use....that said, in the bottom of the bore, looks like there's noticeable wear...most pumps have a wear plate there. The cam also appears to have a fair amount of wear...you may want to see if they offer a major service kit for the pump...
 
I’m positive the hoses are correct. Just took it to the lake backed it in and bam worked great. Pulled it out took straps off. Put it back in and nope no flow. Stopped a mechanic at the docks. He said if I had water coming from one of those 4 holes that that means exhaust is probably filling that cavity as designed and pump is sucking in exhaust gas. Thoughts?
 
sandkicker said:
Are you sure you did not reverse the in and out hoses? ALSO, notoriously, for Volvo pumps, there are different impellers available that are very slightly different in size... ONLY the exact one will work. Owned/maintained boats for over 50 years and have learned to not use aftermarket rubber goods.
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Sorry I did t see the correct reply button. I’ve posted a few updates. Would love to get your feedback.
 
FWIW.... after having my engine overheat when I picked up a plastic cleaner's bag on my leg years ago, went thru hull with a strainer. Over the years and several boats I've changed to an external wedge shaped strainer with the largest screen hole size available... I also plumbed in a T at the thruhull with a hose bib to make inseason flushing, winterizing and engine testing easy. I connect a 3 ft length of garden hose to the hose bib and put the other end in a 5 gal pail that has a free running water hose in it. BTW, Volvo's fascination with "creative" plumbing sealing methods is a turnoff for me. But then again, I'm just a crusty old retired design/development engineer.
 
Some Volvo drive legs have "gills" on the side that nicely accept muffs, however they also have a hole usually on the bottom of the leg that is not covered by muffs, that will dump water from the muffs, but not when immersed. If your model has this extra hole, plug it while on miffs.




























so
 
sandkicker said:
Some Volvo drive legs have "gills" on the side that nicely accept muffs, however they also have a hole usually on the bottom of the leg that is not covered by muffs, that will dump water from the muffs, but not when immersed. If your model has this extra hole, plug it while on miffs.




























so
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There is a tiny drain hose on the bottom. Maybe the size of a small nail. Does it need to be plugged?
 
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