Bought a 72 some months back that had been sitting for about six years and been working on it a lot and riding it very little it seemed to me and right when I was gaining a little trust with the old girl she starts making some noises I didn't want to hear. I got her back to the house and the oil is full of shiny metallic stuff that looks like brass to me. Any how I got the motor out and top end pulled off. The cylinders are at .070 and the rear is scorched on the front and rear of the cylinder wall pretty bad. It had two different makes of pistons in it and not sure why or if it was right but the base gaskets were blocking off where the oil could return through the cylinder back down into the cases. The bike had an Andrews B grind along with a Crane Iggy. My winter project just became a lot more in depth than I had anticipated. Money is tight but I'm gonna have to do something even if it's wrong.

 

I have a 73 FLH with a stock motor. The holes in the cylinder bases are blocked on mine. I can't say for sure, but I think that they are open on strokers. Sorry, but I can't help with the rest.

 

Check your connecting rod and camshaft bushings, Sounds like some one threw her together just to cash it..... Sorry to hear man.... Got a manual?

 

98hotrod I have a manual and the cam bushing doesn't look to bad as far as the amount of debris that is in the oil so im guessing it's the rod bushings as I have yet to split the cases. Yeah I haven't had very good luck when it comes to purchasing a bike and riding it for more than a couple hundred miles before needing some major surgery but in the end I'll either have a basket case scooter or a kick a$$ Shovel hopefully when it's all said and done the latter of the two

tbp looking at the manual it's hard to tell but the oil system diagram looks like it should drain back down through there but I could have been mistaken and will check again tonight if I get a few minutes

 

Find out what size pistons those are, the cylinder walls look thin in that picture. Post back the piston measurements as I have several new sets of 74 pistons I got on the cheap over the years I can part with to help a guy in a spot.

 

Bigger concerns would be crank pin, IMHO. Take a hold of your connecting rods to see what kind of free play up and down on that crank pin. Should be next to zero. Good indicator if you need to split the cases. If it's tight, I wouldn't bother with anything but the top side.

Keep us updated ... Love those old shovels

 

Okay so I went ahead and split the cases. Taggs the rear rod felt pretty snug up and down but had a little side to side movement.The front rod has close to .040 movement side to side but feels pretty snug up and down. I'm gonna do a full rebuild. I noticed that the rear cylinder had a mod done to where the oil was supposed to drain back through the cases but the gasket kept the oil from doing so and the mod had a roll pin blocking off the original oil hole..The front cylinder was replaced at some point and did not have the mod done. I included some pics of the modifications.





TwiZted,Thanks for the offer and I measured the pistons and best I can tell they are 3 7/16 but have .070 stamped on the top of them. I sent you a PM also.

 

Yeah that's what I was afraid of those cylinders have been over bored as far as they can go, sorry man but this ones going to get involved.

 

I agree with TB, the jugs are maxed out for resizing. You may want to attempt to clean them up by honing, but not likely they will clean up to be within safe specs. Not sure of your tool box but to even hone them could mean a trip to a shop capable of doing it and miking them. Replacement jugs may be your best bet.

The connecting rod side play is ok. Sounds like up and down would tell me the crank pin is good. The only thing you need to weigh out, going this deep,do I go into the bottom and complete peace it's solid when complete. Or just go the top end with the question in your mind, how long before the crank pin goes south??

I understand the dollar pinch. It's a pricey job no matter what. All I can say is, the shovels are noted for soft crank pins. Running it if a rod lets go will take out engine cases. Doing as much on your own, you could do just the top and listen for strange noises when complete. Any noticeable noises after that your probably going back into it.

Best luck...

 

Well a couple months and several thousand hard earned pennies later I have my first TroubleShovel going back together. I went back with 80" wheels and some of the parts and pieces I used may not be up to par with some but all I can say is it will either run and hold up or it won't at this point. I'm ready to put the motor back in but keep tinkering with other minor stuff. I'm hoping to hear her run before to long.