Topic: Maui Z1 1973

[MauiK3]

I hope to post some, I’m just having a tough time getting the time. It’s been busy here

[MauiK3]

Yesterday I put the cams in, no valves, spins easily!! Before that I tried to push oil up into the head via my air pressurized canning jar through the oil gallery port on the points side of the gallery. None showed up, I attributed that to the rate of flow I could generate, which isn't much. I had the regulator way down, I pushed two quarts but it all went to the oil pan. I even blocked the oil pressure switch off so I couldn't flow back that way.

So I put the gauge back in, set the oil pressure switch back up and spun it using the starter. The oil light went out right away, no oil showed up at the cams and the gauge didn't bump off the peg at all. So now I have to look for a few things.
Is the pump actually making enough oil pressure to do anything? I guess I have to look into it again,
Is there a large unseen hole in the oil gallery that is dumping the oil back to the lower engine?

The mystery continues.

[BenelliSEI]

Following and baffled...... That “feather test” definitely suggests no obstructions. When I do this on a cb750 (plugs out, spinning up to see oil pressure before a first start) I usually see 40-60 psi just on the starter! I suspect the pump?

[MauiK3]

I’m thinking pump. Here is a photo of the little oil system I pushed oil in with, I don’t think I ever generated enough volume to overcome the crank feed losses. There is also a photo of the gauge, that needle did not budge during cranking. I’m going to do an open tube test by putting the gallery plug with the fitting and tubing back on and cranking with the tube up to see how far up the oil is pushed.
I either have a hole in the main gallery spilling all the oil back to the crank case or pump does not generate enough oil to supply the head, very strange, at least I’m narrowing down the possibilities. Hopefully I’ll find something to fix.

[Alan F.]

Could this be the reason the bike was parked by the PO?

[PeWe]

Found oil pumping problem during the test is going forward for this build.

The detailed  root cause is soon found so this can be sorted and bike back on the road without worries.

[seanbarney41]

Following and baffled...... That “feather test” definitely suggests no obstructions. When I do this on a cb750 (plugs out, spinning up to see oil pressure before a first start) I usually see 40-60 psi just on the starter! I suspect the pump?

just so you know, the Z1 engine is quite different from a Honda, in this respect.  It has a roller bearing crankshaft, not plain bearings like a Honda.  So whereas the clearance built in to a Honda's main and rod bearings actually need high pressure, and when correct, add to the pressure for the top end, high pressure would actually work towards pushing the Kawi's roller bearings apart.  You should only ever see less than 20psi with a Kawi.  Less than that, when fully warmed and idling.

[grcamna2]

Steve,with oil in it while cranking it over with a hot battery to the starter,it didn't even register 1lb. of PSI on the gauge ?

[Terry in Australia]

Well that’s excellent progress Steve, and while you haven’t solved one mystery you now know why the engine locked up and your cam bearings are seized. I reckon it wouldn’t hurt to buy a used oil pump (or borrow one if you know someone with a spare) and swap it out with yours to see if that makes a difference before you pull your engine down again? If you can’t find one, I think the one for my 1428 KZ1000 is in a box here somewhere, it’s just an old used OEM pump, but I’ll be happy to loan it to you, if you’d like?

[MauiK3]

First, yes, I did not see the gauge needle even bounce a little. If the pump is working then there is a massive leak or bypass robbing the oil, I will look but there are only a few places that could happen. I’m going to do a few more little tests before I remove the head and cylinders and oil pump to look the gallery over some more. My oil pump bucket test showed that it can move oil but not how much head it can generate.

Terry, thank you for the offer, I may take you up on that, of course I would cover all expenses. I’m going to try to find a pump just for fun.

I feel like I’m getting closer.

[MauiK3]

I ordered a pump from EBay, hope for the best. Maybe I’ll do a bucket test to see if it seems different

[BenelliSEI]

Following and baffled...... That “feather test” definitely suggests no obstructions. When I do this on a cb750 (plugs out, spinning up to see oil pressure before a first start) I usually see 40-60 psi just on the starter! I suspect the pump?

just so you know, the Z1 engine is quite different from a Honda, in this respect.  It has a roller bearing crankshaft, not plain bearings like a Honda.  So whereas the clearance built in to a Honda's main and rod bearings actually need high pressure, and when correct, add to the pressure for the top end, high pressure would actually work towards pushing the Kawi's roller bearings apart.  You should only ever see less than 20psi with a Kawi.  Less than that, when fully warmed and idling.

I didn’t know this. Could the roller bearings be the “open bypass” issue? Do you suppose the engine actually has to be running for the oil pump to generate enough volume to get oil up to the head/cam journals?

[MauiK3]

I've thought about that but then it would seem that the cams have to wait quite a time for oil to get there starting from an fresh fill of oil.
Others have said that I should be able to do what I've done, the spin test on just the battery, and see oil up there.

[grcamna2]

I hope that it's not a gasket,etc. blocking or diverting an oil passage.

[MauiK3]

Two more tests.
I re-oiled the cam bearings and put a tube on the gallery port above the points. The oil came out and rose higher than the cams.
Next I put the gauge back in and still no needle movement.
Next I’ll do another check to see if there is a flow leak somewhere else, otherwise it must be the pump.


I’ll post a clip, forgot how to do it.

[MauiK3]

[MauiK3]

For some reason the videos don’t work, have to keep checking

[MauiK3]

Ok, the videos play on my laptop and not on my iPad, weird

[grcamna2]

The videos play for me.

[Kelly E]

At this point I would put in a known good pump. It's cheaper than ruining more parts.

[Terry in Australia]

Yay! That’s an excellent test Steve and proves that while a “low pressure” oiling system, Kawasaki Z1 engines have a “high volume” pump to make up for it. The fact that the oil is freely moving uphill is proof that your pump appears to be working fine, but it also appears that there’s either a blockage between the pump and the cams, or as you’d previously thought, somehow the oil is returning to the sump without making it to the head.

I wouldn’t be too fussed about the oil pressure gauge not reading when cranking the engine, once again it’s only a low pressure system. The main thing is that you’ve solved another question, your pump works, but there’s something blocking oil flow to the head. Give yourself a pat on the back, you’re almost there!

[craz1]

Have you actually taken apart the pump and inspected the gears. If so what gasket did you use. some are too thick and may cause blow by. The last 73 I pump i inspected was good and I made my own gaskets to obtain a good clearance.

[MauiK3]

I've had it apart to measure, twice. The gasket was NOS.
I'm about to take it out again and look at that, gear pumps are "almost" positive displacement unless there are losses around the parts.

[PeWe]

Can the pump gasket cover oil holes? Flipped?

[BenelliSEI]

This is making me crazy! Hope you find something soon……