Harley VL cylinder galling

[Buster]

Just galled the front cylinder on my 1931 VL for second time. 4.5-5 thou clearance, priming with 2.5 oz oil and accumulates 5 oz after 200 miles in cases. How many oz should I be priming with and how many oz should I accumulate in cases. Crank bearing and camchest is oiling. Believe my initial priming is not providing high enough oil level to reach flywheels to oil front cylinder. Thanks.

[T. Cotten]

Just galled the front cylinder on my 1931 VL for second time. 4.5-5 thou clearance, priming with 2.5 oz oil and accumulates 5 oz after 200 miles in cases. How many oz should I be priming with and how many oz should I accumulate in cases. Crank bearing and camchest is oiling. Believe my initial priming is not providing high enough oil level to reach flywheels to oil front cylinder. Thanks.

Please, Buster,

Can you post pics of the associated galling upon the piston skirts?

It may be a clue that oiling is not the issue, or at least the only one,

....Cotten

[Buster]

This cylinder has passed leak down tests and has peak seals on intake. Intake nipples were pressure tested. Don’t believe I’m priming with enough volume of oil possibly.

[T. Cotten]

I was curious if there may be a slant on the piston scars, Buster,

But that's SO fried, it is amazing that overheating, noise, or smoke wouldn't have alerted you sooner.

I hope you used a constant, regulated air supply for the bubble-test, and snooped absolutely everywhere, even the headgaskets and sparkplugs by turning the motor through.

"Peak" seals are a liability if the manifold spigots are not pristine, the seals custom-cut to a squeeze-on fit, maximized within the nut rather than brass-thin, and scrupously matched to the internal bevel of the nuts, which could be anything these days. Mass-produced one-size-fits-none PEEK seals have ruined the brand.

Wouldn't an oiling problem eat the other cylinder too? It looks more like an interference (or debris) issue; What overbore is it, and was the cylinder ever sleeved?

...Cotten

[dukekleman]

Buster,

You are correct, that piston is lacking proper lubrication.

Now of course the task of pinpointing why the lubrication was not present...

Duke

[Steve Slocombe]

Dear Buster, it's always the front cylinder that nips up on the VLs as it's a struggle to get oil there. The flywheels rotate clockwise seen from the timing side, so oil is thrown into the rear cylinder but struggles with the front. Harley fitted full baffles under the front cylinder and half baffles under the rear to try to get oil mist preferentially sucked into the front. Baffles are often damaged or knocked out deliberately, so watch out for this. The forked con rod is at the front on the VL but at the rear after 1940, so you will sometimes see VL rods reversed which affects the oiling. I'm building VLs slacker these days, and might go 6 thou piston clearance on the front cylinder and 5 on the rear. Also remember VLs were never originally fitted with oil rings but most of us are fitting the Eastern strutted pistons with oil rings. I now omit the front oil ring, and the rear one too on a couple of racing-type engines. On oiling you are trying to keep 4-6 ounces, say 150-200 ml in the cases at all times. Check my VL book for running-in tips. First check your hand pump is delivering about 50 ml per full stroke, drain the cases, put in 3 strokes of the hand pump, go for a ride, drain cases into a measuring cylinder, repeat until happy.

[Buster]

I'm not priming with enough oil. Only been pumping 2.5 oz and it is not reaching flywheels. Thanks.

[Jerry Wieland]

Just galled the front cylinder on my 1931 VL for second time. 4.5-5 thou clearance, priming with 2.5 oz oil and accumulates 5 oz after 200 miles in cases. How many oz should I be priming with and how many oz should I accumulate in cases. Crank bearing and camchest is oiling. Believe my initial priming is not providing high enough oil level to reach flywheels to oil front cylinder. Thanks.

Buster - IMO - One of the problems with HD's total loss oiling systems is that the oil flung up from the flywheels does not get to front cylinder. Usually the rear cylinder catches all of the oil and the front cylinder starves. The old dealer around me said he used to leave the oil ring out of the front piston so more oil stayed on the cylinder wall. I also think that the baffles might have been designed to help get the oil past the rear hole.

Jerry