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Problem with initial valve adjustment after rebuild

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leadnavel:
I was able to get back to the project yesterday and swapped the pressure gauge for the oil pressure switch, pumped the kick start a few times (50) still no oil coming through! Before I remove the oil pipes (hopefully tomorrow) from the oil tank to check those, I thought that I would try a suggestion given by Hondaman on the other place.

http://forums.sohc4.net/index.php?topic=12686.0

Basically it’s a kicking/bursting routine. Firstly using the kick start 40-50 times then a short burst of the starter for 2-3 seconds then do it a second time. I did this routine 4 times, making sure that the oil in the sump didn’t run dry, this didn’t work for me either. All that I’m still getting is the oil from the sump getting pumped back to the oil tank when kicking it over (or using the drill attachment to speed up the process) with the sump running dry.


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K2-K6:
Something definitely odd there, it shouldn't need so much spinning to get any output.

The scavenge side is obviously fine (different segment of pump) and should outstrip the pressure side always by design capacity (else all the oil would end up in the sump when running) so ok there.

I'd definitely check supply of oil to the pump before turning the engine any more without oil supply. 

The pressure guage won't make any difference if there's no oil. It all has to go to the filter first (through that delivery pipe to filter housing) to get to any components, there's no other route. Not worth putting the filter on until you see oil present in that delivery route as nothing else will be supplied.

Without the oil pump fitted, the oil tank content should run through the supply pipe and out the hole the oil pump fits to.

K2-K6:

--- Quote from: leadnavel on May 25, 2022, 05:13:43 PM ---
--- Quote from: K2-K6 on May 25, 2022, 04:23:35 PM ---Worth checking basics then as it should be doing something.

First would be supply hose from tank to see if it's impeded, then remove pump to inspect internal and verify passage from feed hose down to pump.

--- End quote ---

Both oil hoses are new, the oil pump was stripped and refurbed, that's not to say that not where the problem lays though. Which of the two oil hoses is the feed and which is the return?

--- End quote ---

Did you strip the "leak stopper" valve in the oil pump ? as this could give a problem.

leadnavel:
I’ve got two pumps, I’ve stripped and replaced seals and rings in both of them but not the springs as they A. They looked and felt ok and B. I couldn’t get hold of any. I bought a secondhand pump because on the strip down of my original pump the rotors looked overly marked but I have subsequently done some research on the rotors and found that the marking are pretty standard and I could’ve used my original. If the pipes look ok I’ll remove the pump and double check everything.


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smoothoperator:
I don't know if this helps but I think the info on this thread might be related. I recalled something about using vaseline to overcome airlocks in 750 oil pumps. Also might be better in a new thread as this one has moved onto a new topic.

http://www.sohc.co.uk/index.php/topic,23297.msg218481.html#msg218481

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