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2 Stroke oil flow


sezian
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Can someone tell me if I should see a constant flow of 2 stroke oil from the oil pump to the carb, ie should the small clear plastic pipe be full of oil all when the bike is running ???

Having just got the bike up and going I’ve noticed the oil pipe appears to be sending oil in small slugs with lots of air pockets between oil delivery. I’m not exactly sure how the oil is fed, the pump is working but is the oil drawn via some vacuum from the carb ?

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Can someone tell me if I should see a constant flow of 2 stroke oil from the oil pump to the carb, ie should the small clear plastic pipe be full of oil all when the bike is running ???

Having just got the bike up and going I’ve noticed the oil pipe appears to be sending oil in small slugs with lots of air pockets between oil delivery. I’m not exactly sure how the oil is fed, the pump is working but is the oil drawn via some vacuum from the carb ?

When the bike is running if you pull the cable outer away from the cable guide that goes into the engine case you will see that this pulls the pump pulley round to maximum flow and the pulses (slugs) get much bigger, Do this and hopefully all the air will be ejected into the carb in no time.

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Can someone tell me if I should see a constant flow of 2 stroke oil from the oil pump to the carb, ie should the small clear plastic pipe be full of oil all when the bike is running ???

Having just got the bike up and going I’ve noticed the oil pipe appears to be sending oil in small slugs with lots of air pockets between oil delivery. I’m not exactly sure how the oil is fed, the pump is working but is the oil drawn via some vacuum from the carb ?

You could also use the bleed screw on the pump to ensure you dont just have a pump full of air, In the early 70's we were advised to run quarter to half a pint from the bleed then the delivery tube looked after itself

Regards Jim

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When the bike is running if you pull the cable outer away from the cable guide that goes into the engine case you will see that this pulls the pump pulley round to maximum flow and the pulses (slugs) get much bigger, Do this and hopefully all the air will be ejected into the carb in no time.

I did try this but it didn’t have much effect. I will work on this method again (unless you can offer any other suggestion) and try to disperse all the air. But just to confirm should I see a completely full oil pipe all the time ?

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I did try this but it didn’t have much effect. I will work on this method again (unless you can offer any other suggestion) and try to disperse all the air. But just to confirm should I see a completely full oil pipe all the time ?

Yes you should check out my previous post on an other method

Regards Jim

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I did try this but it didn’t have much effect. I will work on this method again (unless you can offer any other suggestion) and try to disperse all the air. But just to confirm should I see a completely full oil pipe all the time ?

The answer is yes a full pipe should be seen, i assume you have bled the air from the pump by removing the small screw from the top of it until bubbles disappear., you should have done this first before running with the pulley turned to max.

Edited to say i had not read jims reply from earlier which states the same. :blink:

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The answer is yes a full pipe should be seen, i assume you have bled the air from the pump by removing the small screw from the top of it until bubbles disappear., you should have done this first before running with the pulley turned to max.

Unfortunately I couldn’t undo the screw and this turned into a bit of a nightmare. I decided to pull the oil feed pipe off that’s connected to the pump and bleed it that way, after all the pipe is right next to the screw, when the oil was flowing freely I went to put the pipe back on but noticed a small slit in the back of the pipe. So I cut a very small length off, now trying to pull the pipe a little to get it back on the whole thing came away in my hand !!!

You can imagine I was not amused, oil pi**ing out and there’s no way you can get to the other end without taking the side casing off. Anyway after a few hours work and much swearing it all went back together.

The screw is still fixed so I can’t bleed from that and I know there’s good flow from the oil tank to the pump, the pump is aligned correctly and working fine I guess it’s just a bit of patients and running the engine slowly until it’s all bled through.

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You WILL have air in your pump and I recommend you bleed the pump by removing that screw before using the bike or you are very likely to undo all the good work you have done thus far. If you cant than ask someone to do it for you or get another pump.

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You WILL have air in your pump and I recommend you bleed the pump by removing that screw before using the bike or you are very likely to undo all the good work you have done thus far. If you cant then ask someone to do it for you or get another pump.

For sure there will be air in that pump, which will not be resolved until the bleed screw is removed, If the screw is butchered just tap it with a hammer to flatten the head out and if ur lucky a screw driver will undo it .. if not a sharpe chisel to the side of the screw may do the job or if there is enough screw head left a good quality mole grip may undo the screw. so let the air out from that point and the delivery pipe should sort itself out.

Sorry OG for replying to ur post but I was just adding on to yours !

Regards Jim

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There is one correct way to work on these bikes and many wrong ways. Four strokes do have their place in this world.

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