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BF20 overheating problem. HELP!

Ponjon

New member
I have a 2007 bf20. I have ran this motor for trolling applications since it was new. I have never had a problem. Until today. Went to the lake, motor started right up first pull like usual. Cruised out to our spot, threw the lines out and started trolling. . . . After trolling for approx 3 minutes the motor shut off. Pulled the cord and it started right up. When it started back up I realized there was no water coming out of the pee hole. I gave it a little throttle and water started coming out the pee hole but not at a very high volume. Long story short. . . . . If I run at low rpms=no water out the pee hole. If I run at high rpms=water out the pee hole runs fine no overheating. When running at low rpms it is just blowing steam out the pee hole.
I checked intake screens they were not obstructed. I checked the pee hole and ran a wire through it, it was not obstructed either.
My first thought is that my impeller is damaged/inefficient which is why it would only work at higher rpms? My impeller is the original one it has never been changed.
New thermostat?
Any help is appreciated.
 
Drop the leg and check the impeller. Likely it is missing vanes and needs replacing, this is a service part and should be checked/replaced every season.
 
7 years and no impeller?????!!!!
You may have set the record. Your owner's manual CLEARLY states change once a year. Most go two with no problem. Letting one go 3 or more is ASKING for trouble.
Do you change the oil? Service the gear case?
These engines are rugged and will last DECADES. But not without some basic service and care.
Just sayin'.
 
I like setting records........... just not ones for not properly servicing my motor! :) I change the oil and service the gear case regularly. I will change the impeller and see how she runs. thanks for the help
 
ATTABOY! Good attitude! Like skronkman suggests though, you will LIKELY find that there are SEVERAL arms broken off of the impeller. I believe there are five....I will predict there are only partial arms left.
It is ABSOLUTELY CRITICAL that you find all the pieces. If you don't make a concerted effort to find and clear them out they may come back to haunt you. Most of the big pieces will be in the case UNDER the pump. But, some smaller chunks could have made their way up to the thermostat housing area. Since you probably haven't serviced that yet either....it is also time.

This is GOOD advice. PLEASE...take it!

You own what I personally consider the finest, ruggedest, dollar for dollar, more bang for the buck, small displacement OB in the BF20. I would own one myself if I could afford one. Like I said...it SHOULD last for DECADES with just a bit of maintenance. I have experience with these going back to 2003-04 and 05 models with hundreds, if not 1000's, of rental hours on them without ONE MAJOR FAILURE!

Buy the COMPLETE WATER PUMP KIT that Honda offers. It has everything you need for a QUALITY repair. Your housing is most likely scored and worn so just replacing the impeller will NOT get you back to 100% pump performance. See Item #2 on the parts page link below.

http://www.boats.net/parts/search/H...20DK3 LHTA/WATER PUMP IMPELLER KIT/parts.html

In addition....Buy a new thermostat, gaskets and flush valve set. Items 2,3,4,5,7 and 9 on the page listed below.

http://www.boats.net/parts/search/H... and Later/BF20DK3 LHTA/THERMOSTAT/parts.html

THIS IS NOT EXPENSIVE!! Consider that ALL of these items have served you well FOR 7 YEARS! As my old pappy used to say...THEY DON'T OWE YOU A DIME.

And, when you consider that, statistically, over 70% of ALL CATASTROPHIC engine failure begins with a malfunctioning cooling system....This is CHEAP insurance.

Good luck and let us know what you find and how you make out.
 
Also, if you want to do the work yourself, there are some tricks and procedures that are ESSENTIAL to getting it all put back together correctly. The HELMINC. official Honda shop manual is a GOOD BUY. It is much more expensive than the other, "imposter", shop manuals but worth every penny for the DIYer. Far superior to Seloc-HAYNES-CLYMER all of which are NOT worth what they cost.

For example: You will need to separate the upper and lower shift rods at the front of the lower case extension in addition to removing the bolts that hold the gearcase on to access the water pump. The manual would be handy for getting the shift rod adjustment correct when you go back together. You would have clear, concise directions along with the proper specifications for smooth shifting and operation. Get it wrong and the transmission could be damaged. And that's just ONE example.

But, if you need advice on how to do it, that's why we are all here.
 
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