1986 ? 7.5 honda

duckhunter · 03-18-2010, 07:49 AM

Anyone ever have gas in there crankcase. I checked my oil and it did'nt look right and the oil on the dipstick had a strong gas smell. Also when i run it in a 5 gallon bucket i get a oily film on the ring of the bucket. The motor purrs like a kitten but i need to address these problems. Phil

fishkisser · 03-18-2010, 02:11 PM

Sounds like rings or valve guides ...

Smj · 03-19-2010, 06:54 AM

If the fuel pump is on the valve cover, it runs from a lobe on the cam shaft. It may be that a diaphram in the fuel pump ruptured allowing gasoline to enter the crankcase.

Smj

Azeal · 03-19-2010, 08:51 PM

Before you rip into it, do some checking.

Have you had this motor long? Have you trolled with it much before? Is the motor running and starting ok otherwise?

I had a similar problem with my Honda Classic 8 (essentially the same motor with a silver paint job and electronic ignition). Did some research, and it turned out that running cold when trolling is a known problem with these motors (and many other older 4 stroke kicker motors).

When they run cold from the stock thermostat opening too soon, and the spark plugs not being hot enough, you get partially burnt fuel blowing past the piston rings. You can also get water vapor in the crankcase condensing into water, and the motor never getting hot enough to evaporate it out through the crank case vent. Over time this causes the engine to "make oil" and have the problems you are having. A sticking thermostat can also cause these problems.

The fix is pretty simple... Honda makes a hotter thermostat for these motors, and you go with 1 step hotter plugs. This would be the first thing I'd try.

Next possible problem could be a faulty fuel pump diaphragm.

If the rings are bad, the motor would probably have some issues starting and running.

handoff · 03-20-2010, 03:55 PM

sportscraft put a warmer rated thermostat in mine and solved the problem

duckhunter · 03-21-2010, 01:05 PM

Thanks for the heads up everyone.

seadog · 03-22-2010, 05:14 PM

Quote:

Originally Posted by Azeal

Before you rip into it, do some checking.

Have you had this motor long? Have you trolled with it much before? Is the motor running and starting ok otherwise?

I had a similar problem with my Honda Classic 8 (essentially the same motor with a silver paint job and electronic ignition). Did some research, and it turned out that running cold when trolling is a known problem with these motors (and many other older 4 stroke kicker motors).

When they run cold from the stock thermostat opening too soon, and the spark plugs not being hot enough, you get partially burnt fuel blowing past the piston rings. You can also get water vapor in the crankcase condensing into water, and the motor never getting hot enough to evaporate it out through the crank case vent. Over time this causes the engine to "make oil" and have the problems you are having. A sticking thermostat can also cause these problems.

The fix is pretty simple... Honda makes a hotter thermostat for these motors, and you go with 1 step hotter plugs. This would be the first thing I'd try.

Next possible problem could be a faulty fuel pump diaphragm.

If the rings are bad, the motor would probably have some issues starting and running.

duckhunter · 03-22-2010, 08:34 PM

Today i removed the thermostat and changed the oil. Sportcraft is closed on mondays so i will pick up new plugs and thermo tomorrow. The thermostat was froze open so i am pretty confident this is my problem. The motor ran really well before tearing it down so i don't think it is the rings. Thanks to everyone for all the help an info. Phil

duckhunter · 03-24-2010, 01:49 PM

Back together and running great. New plugs and thermostat. Went hotter on both. When i drained the old oil it came out very thin with the raw fuel mixed in with it so i changed the oil ran it for 45 minutes and changed the oil again. Now i am good to go and thanks again for the help. Phil