R5 Autopsy

[Czakky]

 
Rebuilt new (used) oil pump. Same problem... I can manually spin the starter wheel and it's fine. As soon as I get going the lines start filling with air. It seems to get worse with more throttle.
The only thing I can think of is bad check valve springs in the spouts.

Any opinions?


I love the pump and it worked fine until I got these damn clear lines...

[SUPERTUNE]

So tell me why if you rebuilt the pump you didn't use John's oem full kit from Economy Cycles?
His kit comes with new oem yamaha check valve springs...
Didn't you pull the pressed in nipples and change them?

IMO, if you do all of the above, use OEM Part # 90445-05M07-00 lines and quit worrying about it, just tune it.
Just trying to make sense of what your doing...

Chuck

[Czakky]

So you're thinking it's bad check valves?

Two reasons I didn't get the OEM kit from Econ.
HVC sells the the tiny plungers that I spent two hours looking for last time I rebuilt a pump.
Also I only saw a couple of seals in that kit and I thought there were four total.
Oh and I needed the wrist pin clips from HVC.....

I mostly try to use OEM. I'll try this again, with the right parts.

[Striker1423]

So you're thinking it's bad check valves?

Two reasons I didn't get the OEM kit from Econ.
HVC sells the the tiny plungers that I spent two hours looking for last time I rebuilt a pump.
Also I only saw a couple of seals in that kit and I thought there were four total.
Oh and I needed the wrist pin clips from HVC.....

I mostly try to use OEM. I'll try this again, with the right parts.

If you are that frustrated with it you can always send the pump to a fella on the ACRD forum named Arrow. Apparently rebuilding these pumps is what he's known for.  But, he's also in the UK. However, he wrote up instructions to follow that helped me out immensely when I rebuilt mine with new seals (HVC kit as well). At the time I didn't know about the rest of the parts (check ball etc) and mine were not leaking oil, so I left it as it was.

http://www.aircooledrdclub.com/smf/index.php?topic=50421.0

There's also these instruction on full engine rebuild with a step by step on full oil pump rebuild. The tips and tricks he shows are essential to prevent searching for parts for 2 hours.  Even with this I almost did the same thing you did with the plungers.

[SUPERTUNE]

Oh well, that link still shows replacing the springs...

I do offer pump rebuilding...but guess with the old site going away none of my info is around anymore.

Pic's of testing when I'm done...no bubbles.
I made a funnel as a oil supply tank...

Chuck

[Czakky]

If I wasn't so efficient at rebuilding these things at this point I'd take you up on that service Chuck. I'm just learning the lessons the hard way....

One other thought I had. Are the spigots supposed to coordinate with a cylinder?
The left cylinder is quite a bit further but pressure being equal and all I didn't think it would matter.

[SUPERTUNE]

That's a thought...I've just always ran them the way Yamaha did it stock, bottom outlet on the pump-right carb, top outlet on the pump-left carb.
Chuck

[Czakky]

Opposite how I had mine... Problems started after I installed clear lines and probably switched them. Either way I'm rebuilding the pump, again.

[quocle603]

you're a lot like me, can't seem to catch a break with your bike...but you just gotta keep on turning wrenches.

[Czakky]

@Quocle. It has been a super reliable bike until this year...

While I wait on parts from Economy Cycle, here's my rundown.

After rebuild it seemed like the pump was working fine so I upped my jet size to be on the safe side as I also had fresh coils. With the 160 mains (previous 150s) it ran ok until 7k rpm then it hit a wall. I had it in my head due to previous experience that it was rich. Even though the wisdom of this forum would've told me to try and go up first I dropped the mains down to 150. So next ride the pump fails etc. Now I've got a full gas tank and I want to run a gallon of pre-mix after pump is rebuilt again. So I disconnect the pump and mix oil to my 2/3 full gas tank. She's running good but once warm I give it full throttle and it just dies. I did go up one size on the mains to 155 to account for the premix. It seems I didn't go up enough and in fact I have been lean since replacing my coils.
So now I will throw 170 mains in. I'm getting good at swapping mains.
I'm not really asking a question just detailing my struggles in hopes that it might help somebody.

[quocle603]

Bad coil(s) will not let you go anywhere at low RPMs once they are heated up. When I was riding with a bad coil, if I were to idle and twist my throttle...it would not do anything except die. One time, I had to wait in the hot sun at the beach for awhile until the coil cooled down for it to fire back up and ride away. At high rpms the plugs would spark and fire accordingly, so I just took the highway back home. Took me awhile to trace the issue, checked my fuel, timing, compression, jetting, etc.

You can't really jet until everything is kosher and running well. No air leaks, timed properly, strong spark, plenty of compression, and etc.

[Jspooner]

That's not entirely true, sometimes a bad coil is bad all of the time, hot, cold, low or high RPM. When mine quit, it quit all together, I ride the bike to work, it ran fine, left for lunch and it dropped one cylinder pretty much immediately and it was done. Had to ride it home on one cylinder. Swapped the coil out for that side and it ran again.

[AAAltered]

That's a thought...I've just always ran them the way Yamaha did it stock, bottom outlet on the pump-right carb, top outlet on the pump-left carb.
Chuck

You guys got me wondering if the pump outputs are side-specific.  I went to an official Yamaha R5B Service Manual to see what it offered.

There is no actual text that states which spigot is for which side.

There are multiple clear photos that show the oil line routing just as Chuck stated.  Bottom spigot, right carb.  Top spigot, left carb.

Talk about minutia...

It took looking at separate two photos with a magnifying glass to really see the routing...

[quocle603]

That's not entirely true, sometimes a bad coil is bad all of the time, hot, cold, low or high RPM. When mine quit, it quit all together, I ride the bike to work, it ran fine, left for lunch and it dropped one cylinder pretty much immediately and it was done. Had to ride it home on one cylinder. Swapped the coil out for that side and it ran again.

Consider me fortunate. I was just speaking from my experience. I guess I could have phrased it better... 

[Czakky]

At 6k RPM without fail this thing just starts bogging and running like crap. It can sort of "clean out" for a bit and sort of buck and make power but then even if I close throttle it will die..... Definitely not a throttle position thing it is at 6k every time.
I'm freaking lost again.