Honda BF2 issues

CDory23 · Posted: Fri Jul 22, 2016 8:43 pm Post subject: Honda BF2 issues

I went to start my honda 2hp today since I was planning on using it tomorrow and I"m having issues. At first it started and ran but wouldn't idle low and when throttled fully for a few seconds it just cut off completely quickly in almost a jerky fashion. Oil and gas are fresh and full, new spark plug.

It will not start now and when pulling the cord there is much more resistance then I've ever had with. I unbolted and inspected the cord and reel and all is in good shape so now I"m wondering if it became partially seized or there is some internal engine damage, cranckase maybe. every once in a while I can get a good pull that feels normal but 90% of the time it doesn't. I've also checked spark. My compression tester doesn't fit on that small of a plug so I can't get it but there is decent compression when I put my thumb on it.

Any ideas?

thataway · Posted: Fri Jul 22, 2016 9:03 pm Post subject:

Two questions: Was the carb completely drained after last use?

Have you taken out the spark plug and turned the engine over? I realized that these are air cooled, so no water should get in the cyl. If this is true, perhaps some old gas could get into the cylinder? Pretty remote.

CDory23 · Posted: Fri Jul 22, 2016 9:42 pm Post subject:

Just went through the carb which was pretty dirty. completely cleaned and reinstalled. Still no go. yes I removed the spark plug tested compression with my thumb, checked for spark and installed new plug. Not sure whats going on at this point.

Mikew · Posted: Fri Jul 22, 2016 10:01 pm Post subject:

Seems like you could check for excessive friction by removing spark plug and turning over with recoil. It should spin nicely. With plug still out connect wire, lay plug against block and turn over, check for good spark- kill switch off.
It still may be carb related- I found extremely fine holes in jets and throttle body of my Yamaha carb clogged with a white powder. I used a fine music wire and solvent to clean out, ( guitar E string), carefull not to inlarge jet holes.
Mike

CDory23 · Posted: Fri Jul 22, 2016 10:14 pm Post subject:

I removed spark plug and turned over, very resistant still. The cord just doesn't pull smoothly. It also doesn't make the normal noise when pulled. Maybe 1 out of 10 times it makes the normal noise that pull starts make when functioning properly (the chug chug chug). I even sprayed starting fluid in the cylinder as well as air intake and have gotten no response. Very strange....

I cleaned the carb well and do not believe it is carb related at this point. Air, gas, spark all check out.

Sea Wolf · Posted: Fri Jul 22, 2016 11:45 pm Post subject:

Doesn't that motor have a centrifugal clutch? (As opposed to a switchable gear case?)

If the motor seems loose, check the clutch for binding. The motor should start, free of the drive train. Only engages as rpm rises.

Also, check the prop on the shaft. Free to turn? Lubricant in gear case?

How about fishing line wrapped around the prop shaft? Could have melted and bound up tight if run out of water, which would have kept it cool (un-melted).

Lots to think about!

Good Luck!

Joe. Teeth

Discovery · Posted: Sat Jul 23, 2016 12:11 am Post subject:

Buy a new carb. Their about $65 and easy to change out. My BF2 wouldn't start, so I tried for a few days to clean and adjust it before giving up. The new carb took 15 minutes to change, and started on the second pull. My motor was 9 years old, and I had put it away without draining it too many times.

srbaum · Posted: Sat Jul 23, 2016 8:38 am Post subject:

The problem sounds like the cylinder is seizing or a bad bearing. Was there any metal particles on the tip of the spark plug? Change the oil and let the oil go into a jar or other container that you can see through. Let the old oil sit for a bit and see if there is any metal at the bottom of the container.
Assuming that the newly added oil is at the correct level...place a small amount of light lubricating oil in the cylinder, at the spark plug opening. Pull the cord a few times to see if the added lubricate in the cylinder wall makes the piston move easier. If this makes the piston move through its cycle easier, then you may have a seizing issue.
Bottom line is that a cord that is hard to pull on the Honda is not an issue with the carburetor, though if the carb offices are clogged, the engine will not idle or run correctly.
One of my silly hobbies is repairing and overhauling small outboards. I did two complete overhauls of the air cooled 2 HP Honda's last year and even overhauled a water cooled (older version) of the same outboard. Just for note and nothing to do with your issues, the water cooled version was still an air cooled engine, but it had a water pump to reduce noise and cool the exhaust.
Feel free to call if I can aid you in any way.
757-477-1453

CDory23 · Posted: Sat Jul 23, 2016 12:36 pm Post subject:

Thanks for all of the replies. Its definitley not a carb issue.

When spinning the propeller there is resistance and it feels like the clutch is engaged 100% of the time regardless of the throttle position. I have ran this thing out water because it is an air cooled engine as the previous owner had as well, but never for long periods of time. The manual says to not do this and I think I know found out why the hard way. It must have been the final straw and something got to hot, maybe melted. The shaft was very hot to the touch when I ran it yesterday.

I would think the prop would spin free at idle position and then have some resistance when throttled because the clutch would be engaged. You can clearly hear internal parts spinning at all throttle positions when spinning prop. Yes, the gear oil is fresh and full so that wasn't the issue.

Live and learn, I'm not interested in tearing this thing apart but will most likely sell as a mechanics special. In all fairness I have never really liked this motor. It has a lot of vibration and is very loud since air cooled. I think the Suzuki 2.5 is in my future. I've only heard great things about that motor and its only a few pounds heavier.

Thanks all for the help.

Sea Wolf · Posted: Sat Jul 23, 2016 2:50 pm Post subject:

Yup. your clutch is engaged 100% of the time, so it's probably a broken retractor spring or two between the two centrifugal weights that swing out and push the friction shoes into the flywheel's inner surface to engage the whole clutch mechanism, linking the drive shaft and the power head.

Also ( who knows) the Honda might even have some plastic (nylon) sleeves that serve as bearings on the drive shaft of this air cooled motor without a water pump. Run out of water at high rpm? Melted!

Your profile says "CA". Canada or California? (just curious.)

Joe. Teeth

CDory23 · Posted: Mon Jul 25, 2016 6:02 pm Post subject:

Well I couldn't help myself and I dug into the motor today. I should have already known it wasn't the clutch being stuck the when the prop was spun the flywheel didn't spin. The clutch was in perfect shape.

I got down to the bare motor and the flywheel is extremely difficult to turn. Somehow the motor must have seized. Maybe a vital oil port clogged? At this point I'm thinking the motor itself is shot. I don't see myself tearing the actual motor apart and going any further to bearings...at least yet..