Oil Pump Breather Timing

[mrbigcarp]

I just finished a restore on a 1958 XLH. I was having a problem with the oil disapearing. Nothing came out of my breather pipe when I ran the bike. I understand and repaired the oil pump check valve ball and stopped the oil draining out of the tank. All the oil ended up in my primary. Upon further investigation I realized the bottom bolt for my primary chain adjuster was open to my crankcase. I then removed and sealed up the bolt to stop any migration of oil through the bolt threads. The oil tranfer valve is new the one between the crancase and primary. I guess my question is the timing of the oil pump breather. I'm almost positive I got his timiming right as I am very a--l about geting everything right. I get a good positive pulse from the breather when it runs. If the timing was not right would it create too much crankase preasure and would it run as well as it does? I'm planing on puting it in the judging at Davenport and I am bit frustrated with this problem. I'm going to let it sit until the weekend and then try to start it with the primary cover off to see if the oil left in my crankcase migrates back to the oil tank or some how gets into my primary. I can't drain it because the crankcase plug has been welded up. Anyone heard of or seen this problem and any coments on the crankase breather. I don't want to pull the primary cover this close to the Davenport gig. Thanks Loren in Phoenix.

[kg993]

I take it that the tank is draining with no return. I believe you should have some return reguardless of the pump timing. I have found a large variety of objects obstructing oil and fuel lines-kinked lines and gaskets not cut right. It's allways possible that the pin sheared on the return gear.
I'd pull the line off the case and ck. for flow there first.

[mrbigcarp]

Thanks kg993

I have oil return to the tank. I think I'm trying to find out if the pump timing was off a tooth would it increase the crankcase preasure enough to cause the front motor seal to leak by into the primary? Is the "25075-55 Oil transfer valve assembly" a devise that opens when the crankcase preasure get to high because of excessive oil that has, migrated past the check ball, and then pushes the excess oil ino the crank case. If that is the case the oil that ends up in the primary has no way to get back up to the tank. Stupid design wouldn't you have to agree. I know HD didn't install this transfer valve until 55. There must have been a good reason for this modification. Or does the preasure from the primary side get pushed into the crankcase and maybe this valve doesn't close all the way allowing the oil to get through that way. I'm not real sure on this issue and I'm just trying to educate myself and remedy this problem. With all this oil landing in the primary I'm just having a hard time with the fact nothing came out of my breather! I surely appreciate your comments. If you make it to Davenport this year stop by and say HI. I'll have the 1958 Calipso Red XLH.

Loren in Phoenix

[kg993]

O.K.. The breather is hard to get off a tooth. When timing one it's rare to see one line up perfectly but if you move it a tooth either way it will be way off and extreamly noticable. I've seen some pinion Dr. gears with a slip fit and it's possible the motor can roll backwards and push the gears off the splines, maybe get reinstalled and not ck. timing. You won't get a good vaccume pulse at the vent if timing is off.
Is the sprocket shaft seal new? My experience is the pushrod cover corks are the weak link when it comes to pressure.
The 25075-55 I believe was installed first in 57. It's a one way valve causing a vaccume (when they work) in the primary side. It's set too high to draw oil from the primary and normally cranckcase oil won't get high enough to leak thru to the primary. The more I think about it I believe oil was pushed into the primary thru the bolt hole while running. Now that is fixed I'd set the primary level and oil tank level and try it again. Hope it is all good.
Kerry

[mrbigcarp]

Kerry

The brass screen in the oil transfer valve is missing. Looking back at the pictures I took to document this build I realized it was there at one time. I found small bits of what I thought was brass in the primary when I took the cover off to do my inspection. I'm thinking this valve failed and the preasure from the crackcase with oil blew it out into the primary chain and ate it up. I have only run this bike standing still. I ordered a new valve and hope to change it out this weekend. I pushed a small scratch awl in the hole to see if maybe I could reset this little valve and now it blows out big time when I crank it over. Stupid idea on my behalf. I'm not sure what the back of this looks like but it didn't take much to open it right up. I'm hoping there wasn't any damaging parts that fell down into the crancase. I guess I'll find out when I receive the new valve this weekend. I'll then have a better understanding of the valve. Seems strange that the brass screen came out of this stupid litte piece of cr-p. When I explaind this to my mentor Roger Meinke he remembers the bottom chain adjuster hole as being open to the crankcase. I don't remember ever having to seal the threads in the past. Have you ever removed this valve? It doesn't seem like much of a problem to screw out and replace. If it was leaking by it could explain why the primary was filling up and why there wasn't any oil coming out of my breather. Path of least resistance. This whole thing is a new build with all new parts. Almost 9 years of collecting and restoring parts. I'm pretty sure it will pull a 99 point score in the Junior Class. I have been driving it for over 30 years and never had such a wierd problem. I'm talking too much! Any coments are apreciated.

Loren lorencarpenter@cox.net if you'd like to see pics it is a rare one.

[kg993]

It would be hard to have anything go back thru the valve, there is only a small hole on the crank side. I remember them as being difficult to remove though.
Sounds like a nice bike you are getting together. Makes me think about getting started on my 60 XLH, too many projects and not enough time.

[mrbigcarp]

Kerry

I got the valve out OK. I did push the small metal reed like valve into the crankcase. I get the official "DUMB A-- Award" for that move. I'm going to try and fish it out with a small strip of flexable magnetic sign through the 3/4 hole where the valve goes. If I can't it's not really a big deal it can't go into the oil pump breather and into the camgear side because of the breather screen. Still not sure why nothing came out of the breather pipe. Got a good pulse of air when it ran. I'll install the new valve and try it all over again. I need it to run for Davenport and I know it does that. If I need to do any major repairs it will have to happen when I get back. Thanks for your get backs. I'll let you know how it comes out.

Loren