Oil pressure issue?

Hi;

New owner, and my first post. I look forward to meeting (online) many of you.

Just purchased my 42WLA civilian police bike and it starts up and runs good but the red oil light is on (as well as green Gen light). I disconnected the wire at the oil pressure switch and the red light goes out.

I really don't want to run the bike if there is a real oil pressure issue. I have read that the repo switches require much more pressure than the originals or NOS and I am trying to locate one now to replace the one I have as the next step.

Any words of wisdom? Any way to tell if oil is flowing? I ran the bike for a minute and I really couldn't tell the difference in the temp of the oil line coming from the engine to the tank.

By the way I an in new England where is is around 35 Degrees right now and the oil in the bike looks real think like straight 50.

thanks!

Trying it with a known good switch may prove you are okay but you could attempt to observe the return line's output, even if it has to be removed and directed into a catch can. If you have stock tanks on it the return line is near the top and just forward of the oil cap.
I'd start by insuring you have oil feeding the pressure pump by burping the line at the connection point. The stock feed doesn't make alot of pressure but if your getting consistent return oil it has to coming through the feed pump and there are no keys to shear off excepting the drive tangs on the end of the cam driving it making it very reliable.
The oil pressure switch completes a ground thus making an alternate test light simple for testing it without the bikes wiring, but It's likely a bad switch as you suspect.

The bike is all stock and there are 3 lines coming out of the oil tank. Which one is the return line? My service manual has an engine oiling schematic, but it has a poor non-representative drawing of the oil tank.

When I look inside the oil tank there is a pipe on the right side what is this?

Is there any way to see the flow of oil by looking inside the tank? I am pretty low, almost to the refill line and about to add a quart.

When you say "burp the line" to check for flow, do you mean remove, or crack open? And do you suggest doing this at the tank side of the line?

thanks

[Pa]

The return line on the oil tank is the one with the large round tower looking fitting with threaded hole in the side. Inside the tank the return line routes to the top of the tank from that large tank fitting I mentioned. You can view the oil returning from there. The return oil flow will be slow. The return line also goes to the scavenger pump located on the bottom of the engines rear right side.

It sounds like viewing the return line oil flow in the tank to verify the scavenger pump is working is an easy no-risk think to do. Will this only verify the function of the Scavenger pump? Even if I see flow, would it be possible that that other pump is not working?

there is a very good chance that the low oil level in the tank is dew to what is referred to as dry sumping. in which case oil will return to the tank for some time without the feed working. If you fill the tank it will end up overfilled. There is a drain plug in the side of the case at the bottom left side. drain the case. Drain the tank. Put in some thinner oil 20-50 for a test and try it again.

So I checked again for any sign of oil flow in he tank and found none.

I pulled the oil pressure switch while the bike was idling and nothing came out!?? I am assuming oil should be squirting out of there? Next steps?

Not enough info. Did you make certain that you have oil getting to the feed pump? Did you drain the crankcase as suggested? There normally should be several ounces of oil in the cases during and after normal running. If you drained it without refilling then the return pump has nothing to pump until that reserve is once again established.
Being your tank is so low it is a possibility that the check valve in the feed pump that prevents this is leaking through which will cause a condition called "wet sumping" which is allowing the oil to drain from the tank into the cases while sitting for extended periods.
It's not a good sign that you have nothing at the pressure switch when running. Use caution in running it further especially if the cases are void of all oil. If drained as suggested, add 1/4 pint of oil through the timing hole plug before testing again.
If the feed pump was getting oil supplied to it, then you need to pull that pump and see what's lacking.
I also suggest pulling the oil tank and cleaning it thoroughly unless you've already done so. It could have globs of loose sealant in it or who knows???

as 37ulh said. did you pull the feed line off the feed pump see if oil runs out? the old gobs of goo 70wt that could be in the tank from the previous owner won't flow well in the cold. I think from what you have said that that is your problem. flush the tank and use 20-50 for testing. The feed pumps are very reliable however If oil is flowing freely out of the supply line at the feed pump and you still can't get oil to circulate you will want to take the time and pull the pump to inspect its condition and see that the check ball is not stuck (you will need a new gasket and some know how). Oil should be coming out of the sending unit hole even when the engine is not running.

Sound like your tank is full of thick goo and like have stuck check ball. But your in luck wedneday-fri is going to be warm or at least in Ma.
I'd remove your oil tank and flush flush flush...once you think you have it clean use some warm wd40 (comes in gallon can) add a cup and shake, dump. if no particles come out re-install it fill 1/2 way pull off the feed line and drain in to a bucket thi will flush the feed line. check the flush bucket for goo, silicone bits and metal fines.
If you have compressed air remove the crank drain plug, put drain pan under it, blow 10-20 psi in to the pump while kicking slowly (ign off) if you get some oil out the drain. Now prime the oil pump, pull feed pipe off at the tank fill with oil using turkey baster (marvel oil will do or any light weight oil) plumb air 5-10 psi in to feed pipe use air to push while you kick this should prime the pump rehook up the oil feed pump use a light weight oil 10-30 if fine for now. remove the oil light sending unit and pull the spark plugs and kick slowly (kicking fast will only blow out your knee when the starter pawl skips...BTDT) you should see a dribble of oil come out if not you likley have problems in the pump.
Note: you can test you sending unit with compressed air and a multi meter.

The good news is there is nice flow from the tank to the pump. I unscrewed the nut at the pressure pump and the oil flowed freely

I did get 2-3 oz, of very dirty oil to drain out of the plug on the left case. The oil in the tank was very clean by comparison. The previous owner told me he changed the oil a few months ago and did very little riding after.

The bad news is that the female threads that the pressure switch screws into at the case on the right side are broken, see the pic. This still doesn't explain the lack of flow in thee oil tank return, but it may explain why the oil light is going on. I still don't understand why no oil is leaking out of the hole where the switch goes but it appears the pressure pump is not pumping?

broken-case.jpg

broken-case2.jpg

Crap well you got to fix that first....

looks like the home made gasket on the pump may be missing a critical passage. are you having fun yet?

I think the fun really begins when it all gets taken apart and we see what is inside!

Here's to hoping you won't have to go any deeper than the feed pump but if it's been without oil since it's last change as is indicated by it's not functioning plus the fact that the oil in the tank was clean in comparison to the funky stuff you said came from the crankcase...
Do not attempt to blow through the pump unless removed from the engine so any trash that could have developed will hopefully not be distributed further.
Keep us posted on your progress and findings.

Well, it was a bad oil pressure pump and that solved the problem for one short ride (my first WLA ride ever). The problem is that the used pump I put in appears to be wet sumping.

After leaving the bike sitting for a week, it seemed really hard to kick and then i found that it was puking out oil onto the floor out of the front of the engine after kicking. I could actually hear it gurgling. I drained out the crank case and over a quart came out! Now I need to find a way to rebuild this oil pressure pump correctly or find a good source for an aftermarket pump

You have neighbors up the road a ways that makes a very nice aftermarket pump.

http://www.calas-hp.se/e_prod.php


I have 1 on my 1942 U. It still wet sumps after sitting for some time though. I suspect mine is leaking through the cam bushing.
F

Nice pump but really pricey.

I guess I will try to replace the check balls and springs first before I spring for a new pump

Hopefully between the two pumps you will be able to build one good one if they're the same style. There are others that have worked out ways of modifying stock feed pumps for more pressure and volume and your original pump may still be a good candidate for such a mod as it didn't leak through.
Good luck and i would also struggle with paying $500 for a pump that still wet sumps. I don't see how cam bushings could cause wet sumping, sorry!

I wonder how damage like that (in the pics) even happens in the first place. ???!!?