Mercruiser 502's Water Pump by-pass
#11
#12
Both of my engine builders say to always run T-Stats - unless your running big HP blower motors and plan on turning them over 4500 constantly. But if your the average Joe and plan on cruising at say 3400 - 3600 , you'll never build enough heat to remove the moisture in the crankcase ... so they say.
#13
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Joined: Apr 2005
Posts: 966
Likes: 123
20 HP? So has anyone dyno tested the same engine with a water pump vs. a crossover and seen a 20 HP increase?
#14
Both of my engine builders say to always run T-Stats - unless your running big HP blower motors and plan on turning them over 4500 constantly. But if your the average Joe and plan on cruising at say 3400 - 3600 , you'll never build enough heat to remove the moisture in the crankcase ... so they say.
#15
I just have to ask; is it really possible that the engine driven water pump uses 20 HP? I really find this impossible to believe. I have 3" gasoline powered pumps that we use to pump out foundations and manholes. They move infinitely more water (319 Gallons per minute) than a little belt driven water pump. And the Honda engines on these pumps are only 7HP.
I dont really think its apples to apples ....but to answer your question ......no .....
#18
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Joined: Jan 2004
Posts: 4,480
Likes: 43
From: Tennessee
Pasquesi,
You are right. After re-reading, I was thinking of the seapump when I stated the 20 hp number. I was thinking of running the engine with and without the seapump. That pump is worth almost 20, not the circ pump. A lot of builders will not run the sea pump to get a few extra on the dyno. The circ pump is not worth 20 hp. Glad you caught my mistake. I hate giving false info, even if by mistake. Sorry for any confusion.
Eddie.
You are right. After re-reading, I was thinking of the seapump when I stated the 20 hp number. I was thinking of running the engine with and without the seapump. That pump is worth almost 20, not the circ pump. A lot of builders will not run the sea pump to get a few extra on the dyno. The circ pump is not worth 20 hp. Glad you caught my mistake. I hate giving false info, even if by mistake. Sorry for any confusion.
Eddie.
#20
I think your 502 mpi will not respond well to a crossover due to the enrichment function on the EFI that adds fuel when the water temp is cold. If you don't get above a certain temp while running you will end up with poor fuel economy, soot on the transom, plug fouling etc.. Reprogram is possible but a lot of inconvenience for little gain.
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