I have a 1973 175 CT3- oil pump was delerted when I got it and I am working on getting a pump reconnected.  I got two used pumps and rebuilt one- new seals, installed and bled.  The plunger moves but I am not getting any flow- some oil will make it up through the line to the cylinder but it doesn't really flow- definitely not enough to do any goood and no flow at all at idle- even with plunger moving slightly.  Any ideas what to check?  And anyone have a working oil pump for the CT3 you want to get rid of?

Contact member DEET excellent work 

Not sure how you've determined pump isn't putting out enough.  

Best thing to do is measure the output of 200 cycles of the pump plunger both at idle and with pump pulley rotated to full throttle. Pumps don't put out much oil.  You might be just fine.  

Also, putting clear line on the pump is often a bad idea.  Stock hose is tiny, most clear hose has a larger ID.  There's a reason Yamaha did this.  Using a larger ID hose than stock is not a good idea IMHO.

Thanks for the feedback. I have the original oil line. And at first, I thought I would be OK because I saw some coming out. I hooked up a hose and did about 25 to 30 pum cycles and it would work itself up the line a bit a d then stop- And those 30 cycles, nothing made it into the container to measure volume. I guess it could be a pocket of air in there. Too.  

Are you holding the throttle open when you're cycling the oil pump? If not, you're only going to get a very small amount of oil.

Thanks- I did both- I held pump wide open and also at idle- I still have premix I. The bike so I am testing it connected and bike running.  At idle then manually opening the pump al the way and rev the bike to mid rpm’s.  I counted 25+ pulses and  while I did see oil come out, none made it into the syringe to measure.  Next step I guess will be to do the full 200 and just see.  

Maybe it's the crazy heat here but you're not making sense.  

Originally you said you could see the oil making it up the line.  

I mentioned clear line being a bad idea.

You said you're using the original oil line (which is black, not clear)

Tom tried to help and you said you saw oil come out but not make it into the syringe? 

I'm not sure how you could see the oil at all with the original line and it not come out unless you have x-ray vision?   

I'm not saying that clear line is your problem.  But clear line often creates an optical illusion and any line that has a larger ID than stock will often show air near the cylinder (and that's not a great thing). 

The problem is it's difficult enough to help someone solve a problem remotely if the info and feedback is perfectly accurate.  When it starts not making sense, helping solve can be impossible.  

After you post a few more times maybe you can put a video on youtube or someplace, post the link here, and show us what's happening?  (You need to have a few posts before you can post links)

Stupid question from me but i guess the syringe had the plunger out of it.
Just thinking air pressure if the plunger was still in place a bit [although minimal if any] that the oil would make pumping into the syringe nozzle.
Ignore me, reads a bit silly now i've done it.
I wonder if you fitted a clear small diameter line vertically & watch the oil slowly rise.
Even a semi clear line of which i have different sizes for my chainsaw etc.
Pic one of similar size to the outlet union.