I recently boght an old ironhead chopper. I've ridden it in short bursts about 20 miles total. Not having a lot of knowledge about them i was going to check for oil pressure out of curiosity, took out the plug where the sending unit go's added a guage and no oil pressure, removed the pump inlet hose no oil, blew into the tube and heard air come out of the tank. The lines were backwards. I switched the lines an i had pressure and could see oil flowing through the tank. how much damage if any should i expect? the engine sounds fine. I know the run on roller bearings.

 

Others are more expert than myself, but from my limited knowledge i would say virtually no dammage done, especially if it was ridden at lower RPMs. 20 miles is not much. There would have been enough oil to sustain it for that distance. See what others say too.

 

You will know shortly if there was any damage done to the engine.
The first thing that will happen without proper oiling is the cylinder walls and piston skirt(s) will scuff. Then it begins burning oil.
So if you see a blue trail from the pipes, you have done some damage.
How much damage? Cannot tell until you pull off the top end. The bearings being either ball, needle or rollers may come out OK, but I would think the bronze bushings in the timing cover may have had some damage. You will not know until you look.

This is just another fine example for others who buy a machine and trust the seller to know anything about what you have just bought.
The natural rush is to crank it up and ride off. In this case that was not the smartest thing you could have done.
If the oil lines were switched, then it was done by someone who should not be allowed to even own a screwdriver. I fear there are many out there who fall into this class.
Get a factory service manual and learn a little about your machine before you start riding and working on it. Pulleeeze!
Assuming the machine is a 1967 to 1974 (you did not say what year) the oiling situation is this:
The oil feed line will be the lowest on the oil tank. This connects to the oil pump inlet at the rear of the pump.
There are two more connections on the oil tank. One is the oil return line and the other is the vent line. Both of these connections have stand pipes inside the oil tank, ending with an open top tube about an inch below the roof of the tank.
The oil return connection on the crankcase is located just behind the base of the rear cylinder.
The crankcase vent connection is located on the backend of the timing cover (behind the sprocket side cover). You have to remove the sprocket cover to get to or even see this connection. Should be a 90° brass elbow pointing up.............pg

 

Thank you for the information. I will be replacing the oil lines because the feed was rubbung on the chain and almost worn through, WTF? but hey, they saved an inch of hose to use someplace else. I will post later on, If i find any damage I'll send it by smoke signals.

By the way, It's a 1971 XLCH chopster.

 

i have found various diagrams and info online that is wrong regarding this.the bad thing is you dont know if the guy you bought it from ran it like that and for how long....it may have alot more than 20 miles on it.hope it works out for you.

 

thats it. you dont know how long it was run like that, although it wouldnt run to long without oil. if it were mine, and you wanted to be safe, id pull the heads and jugs and check them out, you can also check the crank at that time. see how much play they have. after all it would be cheaper to find a small problem now than to have to replace half the motor later if it were to gernade on you. might be just fine, in that case it would oly cost you some gaskets.