Topic: Maui Z1 1973

[RAFster122s]

Tank bottom looks perfect. Really skilled at making his work disappear or he used techniques that are not easily detectible. The guy is a master metalsmith, no doubt... You are lucky to find someone like him, there are not that many artists like him around

[MauiK3]

That’s why he’s doing the Acty.
He’s also a very nice guy, it’s a pleasure to support local talent like that.

[RAFster122s]

Glad you have the money to do that and to share with us the build and project and candy like his metal work and the paintwork

[grcamna2]

That tank is a Gem,Steve 

[Terry in Australia]

Good work Steve, looks like all your oil passages are good, what’s next? I asked John Clifton if he’s seen the FB post re the torque plate and like me he saw it, but couldn’t find it sorry.

[MauiK3]

Since I have another pump I am going to install it and try a no valves or springs crank test on the battery

[Terry in Australia]

Excellent, make sure that you shoot a vid, I’m keen to see if the new(old) pump makes a difference.

[MauiK3]

I have not posted on this for some time now, between my frustration with it and a host of home projects that have happened I had to set it aside.
I split the cases again and blew air through the system looking and listening for air where it should be and where it should not be. So far the only thing I can verify is air comes out where it should. I also did not hear or see any air where it should not be.
I must say these cases are pretty easy to open and close……3 times.
I have a replacement pump that I installed, it measured fine, perhaps better than the original but nothing too dramatic.
I hope to get back into reassembly soon.
One theory I have, since I have seen no definitive defect is that I may be the culprit. Using my experience with my K3 750 I spin the motor with the battery until the oil light goes out. No plugs installed. With the low pressure system on the Z1 I wonder if that is too much time at a very low rpm, the assembly lube may get “turned out” causing the problem. Just an idea.
I should get back to it soon.
The body work sure looks great, I’m having the same fellow paint our new to me 1996 Honda Acty Attack Kei truck. It’s over on Oahu. Not sure when it gets here.

[grcamna2]

Oh good,you're still 'on it' Steve 

The replacement pump is a good idea;I could feel your pain after a few times with this problem.
I hope this pump you've installed has good working action,etc.

Do you thinking pre-filling all the camshaft oil outlets is an idea,then installing the cams?
Does the system have a check valve which holds the oil up in the head/cam passages ?

Steve,both camshafts are 'true' and bearing fit is acceptable ?

[Terry in Australia]

If it all gets too hard Steve, send it to me, I always wanted a Z1……

[BenelliSEI]

..... I feel your pain.

When the Sandcast barrels were stuck solid to the case, I got really frustrated. Left it for several weeks, got some good advice here, and then worked it out. I’m sure your efforts will be rewarded! J.

[Stev-o]

I have faith in you, Steve...

[PeWe]

How do the Z1-900 mechanics do the builds?
The oil pressure thing is different as you wrote.
High pressure as CB750 is older tech if I have got it right.

I read about high oil pressure crank on a Porsche forum where oil viscosity/quality was up due to early engine failures. Later engines different crank - rod design running lower pressure and  thinner oils. 20W-50 vs 10W-40 oils.

So what is done with a CB750 can differ.
Like how to start the new build, getting oil to crank-rods-cam.

I wish you'll find out and get it running.

I plan to visit my local shop,  leave a crank and alternator for updates.
I'll ask him if he has any ideas.
He has worked on many Z1-900 engines since the Russ Collins era.

[MauiK3]

PeWe
Thank you, I would appreciate any suggestions or help, I’ll split the cases again if there is something I’ve missed. While I was puffing compressed air in through my fitting I made from an oil filter bolt I was sure I’d find a gallery plug missing and causing an oil flow loss right back to the crank case. It’s a pretty simple system of passages. I’ve wondered about the lower cylinder gasket and I make sure there isn’t a blockage there, the head gasket too. I puff air in when the head is on to be sure the puffs make it up to the cam bearing oil holes, which they do.
So I’m left with the oil pump, I changed it and maybe it will work.
Please post if you are given any words of wisdom, I will try anything, I want to ride this thing.

[PeWe]

Yes, we are many that want to hear that beautiful bike back to it's glory!
It is also an unanswered mystery to solve.

[PeWe]

I have got answer from my local shop's mechanic.
He has never encountered a problem like that.
He has repaired and rebuilt those engines (and other engines) since the 70's.
All work needed to double the power for street, racing and dragracing without falling apart.

He wrote that the pump is small and probably need the engine to be started to run fast enough. Only on starter might be too slow.

[MauiK3]

Thank you, if that's the case, my CB750 experience really led me down the wrong path. We'll find out!

[PeWe]

The Kawasaki guys on the KZ forum might have started their fully restored engines like that too.

[craz1]

I pretty much check all the tolerances on the oil pump and get a new gasket. But I never found one that was bad. Cant remember if you took the pump cover off and checked the clearance on the gears to the body. Should be less than .004. Also the gasket is only about .004-.005 I know some of those gaskets you find are way too thick. If you used one of those you may not be getting the flow you need.

[grcamna2]

Steve,have you gotten to the next step of diagnosis on your Z1 ?

[ekpent]

Steve,have you gotten to the next step of diagnosis on your Z1 ?

Yep - step away from the table saw and wood planer.   

[Stev-o]

Steve,have you gotten to the next step of diagnosis on your Z1 ?

Yep - step away from the table saw and wood planer.   

We are getting impatient!

[Kelly E]

Steve,have you gotten to the next step of diagnosis on your Z1 ?

Yep - step away from the table saw and wood planer.   

We are getting impatient!

Yeah, you started first and I rode my KZ 1000 LTD a bunch this summer.  Here's some motivation.

[dragracer]

Okay. This is one of those minor things that can slip by even a seasoned KZ engine builder. It can drive a person nuts trying to figure out why there's no oil pressure. The problem occurs when an engine is torn completely down for cleaning and small parts,are removed.

Refer to the attached pictures and parts diagram. I think you are missed either the spring, the ball bearing or both on the bottom half cases at the oil filter cavity. Number 33, 32.  If any of those pieces are missing,  you will not build pressure becausethis acts as a bypass. Also be certain the o ring on the top case is in place leading from the filter boss. The likelihood that the oil pump is bad are slim to none unless the screen is clogged.

Let me know what you find under that bolt. Good luck.

[MauiK3]

Thank you
I will check again
The bike is mostly assembled, I've avoided finishing to see if I can think of anything new.
I'm pretty sure I can see the ball bearing and push up against it and feel the spring.
If it doesn't run this time I will be forced to sell the project. Very disappointing.