1980 Engine Top End Rebuild

I have a more urgent problem to address now... I got a couple gaskets I was waiting on in the mail today and got the last few things buttoned up before I put the engine in the frame: I installed sump plate, oil filter, and tensioner gaskets; re-tensioned the cam chain tensioner; replaced the o-ring on the bell-shaped cover nut for the tensioner; and took the starter motor apart to check it and clean it and then hooked it up to a battery to make sure it spins.

All of this went well but then I put about 2 qts of 10W40 motorcycle oil in the engine (not to run it on long term, just to lubricate it initially flush it out because this is what I had lying around). I wanted to check if oil is flowing before I put the engine back in the frame. So I kicked it over for a minute and didn’t see anything through the valve access openings. So I loosened a banjo bolt on the oil feed and kicked it over for awhile and still nothing. So I poured 2 more qts of oil in until the level was about up to the full line on the dipstick and I kicked it over for awhile and then hand cranked it and still no signs of oiling. Should I be seeing oil flowing from kicking or hand cranking or would I have to crank it with the starter motor for that? I don’t think there was an oil circulation issue before the rebuild and from what I understand oil pump failures are pretty rare. Any thoughts? Thanks.
 
One of the nice things about these motors is that the oil pump is easily accessible with the engine installed. I can't answer your question as I always use the starter to get the oil flowing. If it were me, I'd put the engine in and spin it with the starter. If you have oil problems, the pumps easy to get to, to inspect and possibly prime if needed. Take the plugs out and remove the valve adjusters and the starter will spin it quiet fast... and the starter's just loafing along with little load on it. You'll get some splash from the cam chain, but look for oil running out of the rocker arms.

Just a thought... did you have the clutch pushrod installed? You'll lose pressure there if you didn't.
 
That’s good the oil pump is easily accessible, but is it possible something else could be causing the problem? I would like to get oil flowing before I put it back in the frame.
Could I spin the starter motor without the engine in the frame with no plugs in to check?
As far as the clutch pushrod, I am not sure where that is because I didn’t mess with anything on the bottom end. Is that the smaller rod in this photo?
1A86669E-BBBB-42B2-BFEE-C8582736A47A.jpeg
 
Other than completely blocked oil passageways... and off the top of my head, I can't think of anything in the oil system that couldn't be addressed with the engine installed. But yes, properly supported, spinning the starter on the bench would be easy enough to do.

And yes, your red arrow points to the clutch pushrod. Good oil pressure will push it out and make a mess. Put the left cover on while you're spinning it to keep it in place.
 
Great, thank you. I will give the starter motor a spin and provide an update. I can’t imagine an oil passageway is completely blocked. It seems very unlikely the oil pump went out during the rebuild also. It was piling fine before I tore it down, I’m pretty sure. The cam, tappets, valve springs, etc all had a nice coat of oil and there was no sign of excessive wear.
 
The battery in the bike is toast and won’t charge above 6V with the trickle charger on it all day. I tested the starter motor with the car battery earlier and sparks went flying everywhere but it spun like crazy so I don’t want to do that again and it would be really difficult with the motor connected to the engine anyway. Is there any way to spin the starter with a trickle charger or trickle charger/shitty battery combination or anything so I can see if it gets the oil flowing?
 
I figured it out. Everything is oiling fine. I needed to prime the oil pump by pouring some oil down the opening at the bottom of the oil feed pipe. It says to do that in the Haines manual. After doing that I kicked it for a minute and saw oil dripping from all the tappets :D
 
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Be aware that that battery is a little longer than the stock one, but maybe that's no issue on your custom build?
 
Anyone have suggestions for a product to use on areas that have rust forming where there is paint. I have read about a lot of different options, but I am most interested in if anyone has used a rust converter product and then painted over it. Ideally I want to clean off or convert the rust, prevent more from forming, and not damage any paint.
 
Well I got everything back together and fired it up. It started right up first try with the e-start. I let it run for a couple minutes and started easing the choke off and it would instantly start to die until I quickly turned the choke back on. I let it run for 5 minutes and once it started heating up it started getting really smoky from all the blaster and wd40 and whatnot burning off even with my 450 CFM fan blowing and the garage door open. I shut it down and pulled the carbs to give them a thorough cleaning. After cleaning the carbs I started it up again and it ran fine. After a minute I turned off the choke and it eased into a nice steady idle. I gave it some gas a couple times and shut it down to hook up the chain, clutch controls, throttle etc. the very last thing I went to do was the clutch control cable. I hooked it up and closed the cover and adjusted the adjuster about 1/4 turn and something wasn’t right with the clutch lever. It wouldn’t pull in or spring back correctly and the cable seemed to be moving fine within the cable cover. I readjusted numerous times, read all the threads and watched all the videos I could find and nothing is working I have tried much tighter and much looser than 1/4 turn on the adjuster, tried different things in conjunction with the lever adjuster, etc. I remember the clutch lever being hard to pull when I last rode 4 years ago but this seems like a different problem. The worm mechanism doesn’t seem to want to turn and push the clutch pushrod when the left cover of the bike is on (it works very smooth with the cover off). I am out of things to try and this is the only thing keeping me from going for a ride. Please help if you have any ideas! Thanks
 
The clutch plates may be all stuck together from sitting so long. I think you're going to have to pull that right cover and pull the clutch apart (take all the plates out).
 
I have been working on getting the engine running and getting everything else finished up to make this thing rideable and I noticed when idling that my starter motor is not shutting off once the key is not turned anymore. The starter motor just keeps turning as the engine runs. I figured my starter switch might be bad and not reverting to the 'run' position from the 'crank' position, but I removed my switch and tested with my multimeter and I believe it has continuity on the correct posts for each key position:
starter switch test.jpg

So it looks like it is a 4-position switch with accessory, off, on (run), and start (crank starter) positions and in my case the accessory is not connected to anything.

I then decided it must be either a wiring issue or the solenoid is just stuck in the closed position, but I am not sure. I went ahead and ordered a new solenoid from Mikes because I figured having an extra couldn't hurt anyway since they are only $25, but now I am working on figuring out the wiring and I have a question. In all of the wiring diagrams that I have looked at, the solenoid low voltage circuit has power coming in on one side and then exiting to ground on the other side, but the way mine was wired previously, the low voltage circuit brings power in on one side and then on the other side it connects (blu/wht wire) to the high voltage post on the solenoid running to the starter motor as shown below:
wiring diagram 5-17-20.jpg

The bike ran like this previously and in theory based on my very limited electrical knowledge I think this would work, but is this the best/proper way to do it? I believe they did this because it would be inconvenient to ground the solenoid due to its location within my electrical system 'orb'.

Also, does it sound like the issue with the starter not shutting down is a bad solenoid? Is there anything else in this diagram that might indicate a wiring issue?
 
JTD1989 said:
I then decided it must be either a wiring issue or the solenoid is just stuck in the closed position, but I am not sure.
Click to expand...
If the solenoid was stuck closed, the starter would run even with the key off. Direct shot from batt to sol. and direct from sol. to starter. As soon as the batt is connected, starter would run... so I don't think it's your solenoid.
 
My large gauge wires were switched in how they were attached to the posts of the solenoid. I didn't catch this initially because the motor would still turn over and run. But this is why the starter wasn't shutting off. I'm glad I got that figured out. I think my wiring is set now. Just have to get some more fuel and hopefully I can get it fired up and idling and get everything tuned.
 
Just when I thought the electric was figured out... I checked and my new battery is not charging. At idle the voltage is lower than it was reading with the motor off and there is no increase in voltage when I give it gas.
Did lots of research and did some troubleshooting. I’m getting 0.5 or 0.6 ohms between each yellow leg on the PMA with the reg/rec disconnected and the engine off. I have read that 0.7 to 1.0 ohms is what we are going for. So that seems okay.
I measured voltage between yellow PMA legs at idle and it was 25-26 V AC for all three combinations and I can’t find a reference for what you want to see, but that seems good. I checked the ground for the reg/rec and the battery and both are good so the only thing it seems like it could be is the reg/rec which I think is a combined aftermarket unit or a problem with the wire running from the reg/rec to the positive battery terminal.
The second case seems unlikely but I cannot rule it out without compromising the wire insulation because of how the connection is sealed onto the reg/rec unit. Is there a way to confirm the reg/rec is my problem here? the only info I have found so far is for the stock reg/rec systems.
 
I went ahead and poked a small hole in the wire insulation on the hot wire coming out of my rec/reg and it has continuity and low resistance 0.2 ohms between it and the positive battery terminal so it should be flowing fine there. It seems like the issue here must be my rec/reg, right?
 

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