Honda BF50- 1001418 Year and compression

[w2much]

Picked up this nice looking little motor a while back and finally have a chance to look at it. There is an issue in the lower unit, feels like a square bearing as it locks up every so many turns of the flywheel. I took the L/U off so I could do a compression test. I crank as my wife holds the rubber nipple type (Hawk) tester in place. Tester shows about 90 pounds on this one cylinder motor. Actually feels like less. What should the compression be roughly? What year is this little beast.
Thanks

 

[w2much]

I just realized there must have been a powerhead swap in the past. Numbers in title are from the powerhead . The following numbers from the IS tag on the swivel bracket
BF50 .1000267

 

[ahicks]

Using the info you've given, I have it around an '85-87. Also, different engine and data plate numbers are not that unusual in my experience.

While 90psi might not be all that great, there's a good chance you're tester isn't up to snuff, there could have been some leakage with your wife holding it, and unless the carb was set wide open, that could also contribute to a low reading.

I'd fix your square bearing issue, clean the carb, and see how well it runs afterward.

 

[w2much]

I put a garden hose on the water tube after removing the lower unit, added some oil and gave it a few yanks. Motor runs great. Lower unit is a different story. As I drained the gear lube I could see there would be problems, lots of fine metallic shiinning up at me. The clutch was shattered which in turn has probably ruined each gear, bearing and prop shaft. The case appears to be usable. I figure about 300 in parts or get lucky and find a used lower unit. So if you know, I am in the market for these parts or a used lower unit for a 5 Hp Honda. Or it goes in the parts motor pile which I hate to do.