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BF8 overheating

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SkipperBrian

New member
I recently went to put my BF8 to bed for the winter and wanted to run the fuel dry. I put on the gear to allow cooling water into the motor and turned on the hose. When I started the engine, to my surprise there was no cooling water coming from the tell tale. I disassembled the engine, and to my horror found that the metal volute case inside the plastic water pump had rotated and cut off the water discharge port. The only thing that holds it in place is a small tab which had been straightened. This to me seems like a manufacturing/design issue and I was wondering if anyone else has come across this.
 
BF8?....pre 2003?

What happened can be expected if the housing and cup haven't been replaced in a long time OR if the pump is allowed to run dry. I have also seen them badly damaged when new if the mechanic forgot to use marine grease on assembly.

Those pumps are very powerful devices that can produce a large amount of heat.

My opinion is that those parts should be renewed about every 5 seasons. Although, I know of some that have lasted more than 10 years.
Not a gamble I would take though.
I would also NOT use a new impeller in an obviously worn cup.

They don't last forever but, my opinion, based on my professional experience servicing them, is that
they are of more than adequate design and quality if properly serviced/replaced in a timely manner.

I do think it unfortunate that the service literature doesn't do a better job of outlining and emphasizing these points but the information for maintaining many parts of an outboard fall short in my opinion.

Sorry you're having troubles.
 
It's uncommon for the metal volute case to rotate, potentially causing water flow problems. While it's not a widespread problem, occasional manufacturing variations or defects can occur. Is the problem solved now?
 
Kenneth, that's what I was thinking. Having been meticulous about ensuring the engine was never run while the water intakes were submerged, I cannot understand why this part would fail. As JGMO said, they can generate a large amount of heat, but with the water as a heat sink to remove that heat, the tab holding the volute in relative position to the housing should NEVER straighten allowing the volute to migrate.
 
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