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OK, this is my first postings on forum asking for advise. It is primarily about managing several oil leaks. But I also would like to share what I have done on the restoration and am “fishing” for comments on my approach to identify any flaws or suggestions. Thanks in advance. OK, here goes:
I have a 1946 UL. After I purchased it, I ran it for about an hour and saw the pri chain was very taught. So opened primary to adjust chain. Chain looked sketchy, so ordered a new pri chain. While waiting for a new chain, bike sat. Didn't want to chance running it with the old pri chain. While waited for chain, noted that it was leaking oil under both heads, between both cylinders and the casing, along bottom of cam cover, and perhaps transmission (oil here could have blown back from base of cylinders). What started as an adjustment became major surgery. Pretty much took everything apart except did not split casings, and did not take apart the steering head. But I figured what better way to really get to know the bike.
Removed heads and found unequal combustion chamber volumes. Cylinders were scored. So I had cylinders re-bored, new pistons, hardened valve seats and new valves/guides, ground one head so had equal combustion chamber volume. Replaced electrical harness, added a fuse (old harness had fried wires at terminals in switch). Along the way, I cleaned and stripped to bare metal old fasteners and parkerized them, or replaced modern ones with decent repros (Colony etc). Replaced F&R brake pads and took springer apart to clean/parkerize all springs and rocker nuts etc. I took cover off transmission and examined teeth on every gear – no chips or gouges. Disassembled and cleaned carburetor. Disassembled and cleaned and greased star hubs. Replaced the gear on generator with proper (repro) slinger type.
Now for the oil system. Took both feed and scavenger oil pumps apart and cleaned. I lapped feed oil pump valve seats and gave a light tap; both using a 3/8” diam SST ball welded to a rod. Replaced SST balls and springs on feed pump. The replacement springs that are available AM do not have the free length listed in Service Manual or Palmer (1-9/32” (1.28”) for check valves and 2-1/16” for PRV). The AM springs for the check valves are about 1.6” long. Harley designed the springs for specific pressure (check valves to open at 1.5 psi), so length seemed important. Based on that, I trimmed check valve springs to 1.28”. (uh oh they say). Another potential issue is the valve seat on pressure regulating valve developed a chip after applying lapping compound. See before after photos. My thinking was oil goes first through the check valve, then to PRV, so that chip would not be a big issue for sumping, because first check valve would (should) prevent/reduce sumping.
I assembled engine and transm with new James gaskets and THIN application of ThreeBond 1184 using a fine paint brush. Only exception to using James gasket was a thinner gasket on the oil feed pump. I made adjustments per Service Manual and Palmer 3rd Edition, checking this forum, and reviews of helpful videos from Tatro Machine and Pacific Mike and others on YouTube. Pretty much any advice I saw, I tried to verify with another source. OK, that’s all good, and really was fun. BUT…
After start-up, changed oil and cleaned oil tank with kerosene. But now bike would start, but was not coming off idle, was stalling. I had missed cleaning interior of fuel tanks. Took them off and found some fine debris in tanks, brand new strainer, and previously clean carb bowl. While I cleaned those up, bike was sitting about two weeks. In that time, the oil drained completely out of oil tank into casing and leaked from several places. Leaks included:
(1) Leaked from a gap between generator (CycleElectric) and casing/cam cover. When I installed gen, I noted exposed threads on the lower generator mounting bolt. Apparently when PO bored out from ¼” to 5/16” to accommodate the CycleElectric, the hole drifted. See photos. There were/are no paper shims (a shim under generator would have made gap worse). I saw this as potential problem during gen install and tried to seal with ThreeBond. The other concern is the screw for the generator strap goes into a threaded hole directly into the front of engine casing. Can’t tell if an oil leak is coming from there.
(2) Leaked from the breather tube. My thought on this is the oil level was so high under cam cover, oil just flowed over the breather tube. If oil was this deep, it may also have contributed to oil coming out at base of generator.
(3) I removed the primary outer cover yesterday. There had been some oil on bottom of primary at seam between inner and outer primary. I was thinking perhaps there was a seal leak at engine shaft to sprocket, between casing and inner primary. However, upon inspection, there was no oil present on surface of casing or on inside of inner primary under the motor shaft. Did same look under clutch hub shaft. There some a small amount of oil on transmission casing below clutch hub shaft. Of interest, there was film of oily sludge, just on the forward half of inner primary. See photo. I used assembly lube on all parts and used a waxy chain lubricant on primary chain. (Prior to bike assembly, I had blown out passage for oiling the primary chain. There was oil under the brass nipple that projects over primary chain, so the primary chain oiler is working). Could the sludge be from Ass’y lube? Or from engine oil mixing with waxy chain oil?
The oil tank is now empty, all of it draining down. I took a swipe of stuff on bottom of oil tank and there is a fine sludge. I am thinking that some of that got onto feed oil pump check valve and fouled it, allowing oil to leak down.
So here’s my thoughts on possible fixes:
Any comments or suggestions on all this would be appreciated.
002 Oil Pump PRV Seat After Lapping_IMG_8443.jpg
007 Primary Sludge Detail IMG_6658.jpg
I have a 1946 UL. After I purchased it, I ran it for about an hour and saw the pri chain was very taught. So opened primary to adjust chain. Chain looked sketchy, so ordered a new pri chain. While waiting for a new chain, bike sat. Didn't want to chance running it with the old pri chain. While waited for chain, noted that it was leaking oil under both heads, between both cylinders and the casing, along bottom of cam cover, and perhaps transmission (oil here could have blown back from base of cylinders). What started as an adjustment became major surgery. Pretty much took everything apart except did not split casings, and did not take apart the steering head. But I figured what better way to really get to know the bike.
Removed heads and found unequal combustion chamber volumes. Cylinders were scored. So I had cylinders re-bored, new pistons, hardened valve seats and new valves/guides, ground one head so had equal combustion chamber volume. Replaced electrical harness, added a fuse (old harness had fried wires at terminals in switch). Along the way, I cleaned and stripped to bare metal old fasteners and parkerized them, or replaced modern ones with decent repros (Colony etc). Replaced F&R brake pads and took springer apart to clean/parkerize all springs and rocker nuts etc. I took cover off transmission and examined teeth on every gear – no chips or gouges. Disassembled and cleaned carburetor. Disassembled and cleaned and greased star hubs. Replaced the gear on generator with proper (repro) slinger type.
Now for the oil system. Took both feed and scavenger oil pumps apart and cleaned. I lapped feed oil pump valve seats and gave a light tap; both using a 3/8” diam SST ball welded to a rod. Replaced SST balls and springs on feed pump. The replacement springs that are available AM do not have the free length listed in Service Manual or Palmer (1-9/32” (1.28”) for check valves and 2-1/16” for PRV). The AM springs for the check valves are about 1.6” long. Harley designed the springs for specific pressure (check valves to open at 1.5 psi), so length seemed important. Based on that, I trimmed check valve springs to 1.28”. (uh oh they say). Another potential issue is the valve seat on pressure regulating valve developed a chip after applying lapping compound. See before after photos. My thinking was oil goes first through the check valve, then to PRV, so that chip would not be a big issue for sumping, because first check valve would (should) prevent/reduce sumping.
I assembled engine and transm with new James gaskets and THIN application of ThreeBond 1184 using a fine paint brush. Only exception to using James gasket was a thinner gasket on the oil feed pump. I made adjustments per Service Manual and Palmer 3rd Edition, checking this forum, and reviews of helpful videos from Tatro Machine and Pacific Mike and others on YouTube. Pretty much any advice I saw, I tried to verify with another source. OK, that’s all good, and really was fun. BUT…
After start-up, changed oil and cleaned oil tank with kerosene. But now bike would start, but was not coming off idle, was stalling. I had missed cleaning interior of fuel tanks. Took them off and found some fine debris in tanks, brand new strainer, and previously clean carb bowl. While I cleaned those up, bike was sitting about two weeks. In that time, the oil drained completely out of oil tank into casing and leaked from several places. Leaks included:
(1) Leaked from a gap between generator (CycleElectric) and casing/cam cover. When I installed gen, I noted exposed threads on the lower generator mounting bolt. Apparently when PO bored out from ¼” to 5/16” to accommodate the CycleElectric, the hole drifted. See photos. There were/are no paper shims (a shim under generator would have made gap worse). I saw this as potential problem during gen install and tried to seal with ThreeBond. The other concern is the screw for the generator strap goes into a threaded hole directly into the front of engine casing. Can’t tell if an oil leak is coming from there.
(2) Leaked from the breather tube. My thought on this is the oil level was so high under cam cover, oil just flowed over the breather tube. If oil was this deep, it may also have contributed to oil coming out at base of generator.
(3) I removed the primary outer cover yesterday. There had been some oil on bottom of primary at seam between inner and outer primary. I was thinking perhaps there was a seal leak at engine shaft to sprocket, between casing and inner primary. However, upon inspection, there was no oil present on surface of casing or on inside of inner primary under the motor shaft. Did same look under clutch hub shaft. There some a small amount of oil on transmission casing below clutch hub shaft. Of interest, there was film of oily sludge, just on the forward half of inner primary. See photo. I used assembly lube on all parts and used a waxy chain lubricant on primary chain. (Prior to bike assembly, I had blown out passage for oiling the primary chain. There was oil under the brass nipple that projects over primary chain, so the primary chain oiler is working). Could the sludge be from Ass’y lube? Or from engine oil mixing with waxy chain oil?
The oil tank is now empty, all of it draining down. I took a swipe of stuff on bottom of oil tank and there is a fine sludge. I am thinking that some of that got onto feed oil pump check valve and fouled it, allowing oil to leak down.
So here’s my thoughts on possible fixes:
1. Remove oil tank and clean it more thoroughly while it is off the bike.
2. Drain oil from casing and cam gear area.
a. I’m not inclined to remove casing drain plug. It is tight to frame and hard to access. When engine was out of frame, I removed drain plug and tried to replace it, but the new machine screw plug (Colony) did not thread well, so went back to original plug.
b. Drain by removing oil line at the scavenger pump. I can turn over engine using kicker to get pump to cycle out most of oil.
3. Take feed oil pump off of casing and clean it again.
a. Examine valve seats.
b. Replace valve springs with proper NOS springs (if available - no luck so far).
c. If can’t get NOS springs, use the AM springs at 1.6” length for the check valves. Interestingly, yesterday evening I saw a video by Tatro from 2016 where he measured wire thickness, coil diameter, spring length, and compressed spring length on several springs. On the 1936 check valve springs (26363-36), his dimensions were 0.018”, 0.312”, 1.6”, and 0.562” respectively. I checked some extra AM springs I had and they were very close to those dimensions. So I’m a bit more confident in using the AM springs. (By shortening the springs, I probably contributed greatly to my sumping – oops)
4. Generator. Two options after draining most of oil from crankcase:
a. Leave generator in place. Clean off surface between generator and casing where threads are exposed and apply a thicker layer of sealant. Perhaps Permatex 82180?
b. Remove generator and check face where the lower mounting bolt passes through and try to seal it better. (Minor challenge here is that strap for generator was a very tight fit. When I installed, front cylinder exhaust was off and access was easier. I needed a ratcheting bar clamp to compress the strap to expose sufficient bolt threads to affix the nut. Reviewing literature, I see there are two straps, one for OHV that is 8-9/16” and one for BTSV that is 9” long. Apparently, I have an OHV strap.) Once generator is removed, I would build up a shelf of JB Weld around the outer edge of 5/16” lower bolt mounting hole to replace material where threads are now exposed. Then grind the JB Weld smooth with a Dremel. And then measure the strap and if it’s an OHV one, replace with BTSV strap.
Any comments or suggestions on all this would be appreciated.
002 Oil Pump PRV Seat After Lapping_IMG_8443.jpg
007 Primary Sludge Detail IMG_6658.jpg
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