oil pump bleeder bolt and bubbles in lines

[CJF]

Just a quick update. I tested out the new line I made up and it didn't work. I think the Polaris check valves I used may have a higher cracking pressure than the T500 lines. The pump didn't push the oil through my fabricated line, while the other side line (stock) worked fine. I ended up giving up on the line and picked up a used replacement...which also has a leaky check valve.

I also rebuilt another pump with new orings and seals and made sure the oil tank breather is clear. The end result is that there are still air bubbles in both lines....small bubbles and not constant. Not sure if this is normal or not....seems like it is still getting plenty of oil, just bugging the hell out of me.

[Vintageman]

CJF

I wonder if we use a seperate check valve like this

http://www.usplastic.com/catalog/item.aspx?itemid=24234" onclick="window.open(this.href);return false;

and then Banjo with no check valves.

These go down to 1/8" (not sure if in Metric) and crack open at 1 PSI which should be OK for avarage Oil Tank Height ( up to ~2 ft high... check my math)

Also given such low pressure maybe just use good low pressure clear/blue lines like that you find on a Snowmobile primer .

More Like Yamaha RD style

[Vintageman]

Those plastic mini check valves may not take the temperature.

The CV or 110 Series here may

http://www.aimsfasteners.com/metal_check_valves.html#cv" onclick="window.open(this.href);return false;

[CJF]

I do think the in-line check valves could work, but I'm not sure where to find the 6MM banjos with the right size inlet where the hose would attach. Any ideas?

[Vintageman]

Can't find banjo yet. Even if 1/4" with 1/8 barb... I'll ask my mechanical mates... so many people make this, but never what you want


Do you think this 1/8 Barb fitting with metric threads would work instead of Banjo?

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... ink:top:en" onclick="window.open(this.href);return false;

http://www.ebay.com/itm/Nickel-Plated-B ... 69&vxp=mtr" onclick="window.open(this.href);return false;

Too bad not right angle, but then if so my have interferance to srew on

As long as the line and check valve is lower than the inlet to engine the line should not bleed empty after sitting a while.

The tygon tubing, Is it real hard stuff? I think the pump is a positive displacement. The reason it did not work with the snowmobile check valve is they may have higher break open pressure, but since the pump puts out so little volume the line may have simple expanded and then contracted pushing oil back into pump.
A lower PSI check valve maybe be OK. And/ Or put the separate check valve closer to pump so less line. Still keep it lower than inlets to engine.

Yamaha RDs is the line is soft. The pump is lower than inlets, the check valve in pump?

[Vintageman]

here is a kawasaki number that shows still avilable by Dillon Brothers http://www.powersportspro.com/" onclick="window.open(this.href);return false;
used on many bikes...

here is the number

92061-018 (no check valve)


16128-009 (check Valve)

[ConnerVT]

The tygon tubing, Is it real hard stuff?

Tygon is very stiff. It does not expand under pressure, and is very resistant to heat and solvents.

I've used it for years in manufacturing equipment.

[Vintageman]

Since oil is not compressible and the Tygon is not elastic in behavior, I suppose since the pump piston since it has no ring like seal the little bit displaced by the piston may slip by it with high break pressure check valves. I assume all seals and orings are good

More likely there is elasticity in system (always is) that is stretched based on high breaking pressure.

What is the break pressure of the Polaris Check Valve?

Possibly more importantly, what is the break pressure of the Kawasaki Banjo with check valve I show listed. I fit is a 2-4 psi like Suz original, than CJF is good to go using these instead!

[CJF]

I'm not sure what the break pressure is on the Polaris or the T500 for that matter....which is part of the problem. I was thinking it would be the same as the Suzuki check valves, since they both run off Mikuni oil pumps.

A post on the Kawasaki 2 stroke forum said the break pressure on the H1 check valves is is 4 PSI.

[Vintageman]

The T500 manual says 3.8 or 3.6 PSI ... read it the other day

I fixed my GT250 lack of oil flow issue (what a mess ruined crank, cyls, and pistons) on my GT250A . An yes seals are the same as t500 I believe (hard to read writing)

I think the lines were plugged for the pump and seals are fine. I used about 10 PSI to clean out line and flushed tank well.

The check valves open somewhere between 5 and 3 psi. I removed Kick started gear under clutch side cover and ran the pump drive with drill ... after a few minutes all the air came out and all line flow nice and even.
Don't seem to leak. If you can get a good stock that is best.

Oh. One spare set of lines I used about I started at 145 PSI air for a significant period. They survived: still open between 3 and 5 psi . Wouldn’t recommend it but they are somewhat robust… sample of one line and two check valves