Single cylinder shovelhead?? - The Harley-Davidson Riders Club Great Britain

**Panhead Boris** · #1 23-09-2007, 10:10 PM

Taz's shovel seems to drop the front cylinder when it gets hot (after 15 miles or so). It starts second kick when cold, and runs REAL strong, then suddenly drops front cylinder with no warning / progressive symptoms.

It's a 1981 80" FXWG rebuilt by a highly reputable independent about 6000 miles ago, runs S&S Super E and points but otherwise pretty stock as far as I know.
When it drops to just running on the rear cylinder the front plug is always wet and smells of fuel. In a service station we checked points, changed condensor to no effect, then tried swapping to my HT lead, then my coil, which made no difference.

Must admit I'm pretty puzzled. We are going to attack it in earnest next weekend. Has anybody got any ideas please?

#2 23-09-2007, 10:14 PM

Get a couple of those neon plug caps from Halfords, you see straight away if it is the spark, doubt it though as it single fire (Innit?) so both pots would go. It does sound like it could be a heat related thingy though, has it got solid pushrods? if yes are they adjusted properly?

#3 23-09-2007, 10:15 PM

Oh and try new plugs and that the inlet doo dahs are done up tight enough, by doo dah the big jubillee clip type things.

**Kiwi** · #4 23-09-2007, 10:33 PM

is a valve sticking open?

sometimes the tolerences on the valve guides are too tight and the valves stick open

**Panhead Boris** · #5 24-09-2007, 12:07 AM

Thanks for that guys.

I have checked ignition and get a good spark on both plugs (yes they do both spark together)

It has hydraulic lifters which is where I was planning to check next.

Also, it has bags of compression but I guess a peak at the valve movement needs to be done.....gonna be tricky as I guess we'll need to get the motor hot to diagnose.

**chilly** · #6 24-09-2007, 10:06 AM

Plugs are a good place to start,they maybe spark ok outside the engine ,but under compression is a different story,well worth changing or swapping over just to make sure the easy fix is tried first.

**Panhead Boris** · #7 17-05-2008, 07:47 AM

I forgot to complete this one for anyone that is interested.

It was the rings worn. Surprised the hell out of me, but all sorted now.

Thanks again for the advice above.

BaZa® · #8 17-05-2008, 08:59 AM

Thanks for coming back and completing the story always good to get a ending. Successful as well is even better well done Boris....BTW how's the new job going in London..