Hey, just picked up a 1976 FXE as a second / project bike. Previous owner refreshed the top end then never installed the gas tank or ran it, it sat for 5 years under a carport afterwards.
Got it home, mounted tank fuel lines etc. new battery & she fires right up and runs awesome. I was taking it real easy warming her up and breaking in easy,changing fluids etc, etc.
Today I took for a ride and everything was great. The after 3 miles rear cylinder started popping & then suddenly it sounded like an exhaust leak at the rear cylinder. Now she's pretty much running on the front cylinder. Compression is 110psi front & 50 psi rear. Checked the push-rods and they seem normal.
Maybe someone has seen rebuild failures similar? I realize I need to tear it apart but wanted some past experiences with Shovels as most of my tear-down experience is on Evos. I have a manual, tools and decent wrenching experience. Just seems to me with the leaky hissing sound that it may be a bad seal in the head, otherwise would it be a valve, rings, or worse a HOLE in the piston? Something else?
Thanks in advance.

 

Update: Now that she's cooled down, I checked the pushrods again. The intake pushrod is bent!

 

you could have a bent valve push rods only bend if they come to a stop against something like the valve

 

Yeah, I'm considering that.
I'm thinking that it may be possible that the pushrod was adjusted too tightly causing it to bend.

 

sure it bottomed out and had no place to go so it went to the side ( bent pushrod )

you will be in a box if you dont remove both heads just to check, also i would replace the lifer roller and even the hydraulic unit as they both were maxed out and just might not work correctly again -- jz

 

Yep ,

OP , the bike have hyd. or solid lifters in it ?

 

Has hyd lifters.
I just removed the rear head to have a look. My head gasket is burned up near the intake. When I removed the intake manifold, I found the rear seal (big o-ring) was pinched off with 1/2 of it flopping around inside. I believe that the heavy detonation due to the intake leak was the culprit to the fried gasket.
Now next the pushrod & valves. The valves look fine, matter of fact they look as new as the previous owner claims, they look like they have the 5 miles I put on them. The pushrods are original according to the last owner and I believe they are and were bent before the refresh.
Rewind - The reason the last guy rebuilt the top end was due to an air breather mounting bolt that got sucked into the rear intake and jammed into the intake valve. The pushrod in question was bent by this incident and was installed back where it was originally.
So, I plan to replace the pushrods, head gasket and give her a whirl.

 

you should take the two heads out side and turn them upside down - put something ( thinner - parts washer fluid - gas - ) out side and in the shade and leave it an hour - if the fluid has gone into the port than you need to have that taken care of - the valve or the valve job is not good -- jz

 

Thanks, that's really good advice. I will do this & follow up with results.

 

OK, did the leak by test on the valves by using gasoline mixes with Marvel oil for coloring. After waiting 1 hour - both heads are good to go with no leak-by whatsoever. Valve job is good, but assembly was very bad.
The head, valve, & cylinder work was all performed by a good reputable local shop.....assembly was by the previous owner.

Thanks again jz for the pointers.