Topic: Maui Z1 1973

[Stev-o]

Let me know if you decide to come here

Thanks...I'm waiting for the Z1 to be finished!!

[PeWe]

[grcamna2]

Oahu has about 1 million people, Maui has about 170,000 not including tourists. The islands are not far apart in size. Steve-o is right , the north shore and some other areas are still very nice and beaches are public in Hawaii which saves it, otherwise they would be mostly closed. Traffic is terrible pretty much everywhere on Oahu. A famous bay that was being killed with visitors (Hanauma Bay) was finally put on some visitor restrictions so the reef could come back and it's doing better. Starting in October, they can't sell sunscreen here on Maui with certain chemicals that tend to kill the reefs here, which are suffering like they all are.
Oh, and I know of one beach that is private, it's a property about 10 miles from where I live and Jeff Bezos just bought it.
All in all, I'd still rather be here than on Oahu, or in Hawaii for that matter, best weather on the planet and property taxes are low.

Kahului is So much more pleasant than Waikiki

[MauiK3]

Yes, I really want the Z1 on the road too. I’m sure I’ll need the garage space for “Acty improvements” when it finally is here.
Getting anxious
And Maui in general is great. My property tax is about 20% or less of what it was in Davis, Ca. Which is near Sacramento.

[MauiK3]

As I plod through the project I got back to points. I found I had to put together parts from 3 sets to get one set that seems to align and adjust well. One of the back plates was sloppy in the engine mounting land, points looked poorly made, etc. I finally got a set that seem to adjust in to spec. I need to look for some NOS point assemblies and get maybe two.
Next I will fill with oil and turn it over before I mount carbs. The valves are adjusted. It’s been tough, many demands on time.

[MauiK3]

I guess I will just admit defeat.
I got it put together today after assembling the head without valves to be sure the cams moved freely in new bearings with caps in the proper position and torqued down. Then I put the valves in.
I put it all together and started it. It started right up, oil light went out, ran great for about a minute and froze up.
Pulled the cam cover and sure enough, cam bearings froze. Plenty of oil pumped into the pockets.
I am out of ideas, I guess it gets parted out.
I was sure it would be ok this time. All the cam bearings showed signs of galling. They were brand new and checked for clearance all the way around. The cams were nicely polished and within spec.
I’m done. This is beyond my ability to figure out why this is happening.
This thing is way too picky for my taste. Something is wrong with this head that is beyond my ability to see or measure.

[ken65]

I guess I will just admit defeat.
I got it put together today after assembling the head without valves to be sure the cams moved freely in new bearings with caps in the proper position and torqued down. Then I put the valves in.
I put it all together and started it. It started right up, oil light went out, ran great for about a minute and froze up.
Pulled the cam cover and sure enough, cam bearings froze. Plenty of oil pumped into the pockets.
I am out of ideas, I guess it gets parted out.
I was sure it would be ok this time. All the cam bearings showed signs of galling. They were brand new and checked for clearance all the way around. The cams were nicely polished and within spec.
I’m done. This is beyond my ability to figure out why this is happening.
This thing is way too picky for my taste. Something is wrong with this head that is beyond my ability to see or measure.

Sorry to hear that.

[ekpent]

I also am sorry to hear about all the troubles this bike has given you.

[Terry in Australia]

Sorry to see Steve, that sucks. Don't give up, there's got to be a reason why it's doing this, don't do anything right now, just put it to one side for awhile and think about it, and you'll eventually work it out. I'm wondering, you've got the cam cover off, why not pull the plugs and observe the oil delivery to the cams by cranking the starter and just watching where the oil is actually going? Maybe after running for a minute it delivered enough oil to the top end to make it look like there was plenty getting up there, but I'm wondering if it was just dribbling in? The oil pressure light could be faulty, I'd be interested to see if you got a reading with an oil pressure gauge?

If all else fails and you decide to sell it, you'll have no problems selling it for good money, but you'll hate it if the new owner finds out that it was just something simple and an easy fix. Are there any good bike mechanics on your island? There's no shame in getting a second opinion.  

[PeWe]

Agree about not giving up.
Really sad that good parts were ruined again.

Maybe test cams can be used until it works, better (real stock) used later.

This bike is a special one that will be a very fine bike. Even better when running as it once did early 70's.

It must be others that have faced same issue. Kawasaki forum....

I could not resist to search. Maybe not the reason here but well worth to add here.
https://www.kzrider.com/forum/2-engine/308340-disintegrating-cam-and-valves

The first reply, answer was either oil starvage or tensioner mounted wrong so cam chain will sit too tight.

[MauiK3]

I'm wondering if the cam bearings I'm getting from Z1 Enterprises may be the culprit. Pretty sure the cam chain and tensioner is correct, it's pretty simple and it's a NOS unit as the bike came with an aftermarket setup.
I had the valve cover off and cranked it, no spark plugs, until oil showed up at the head. The oil pressure switch is NOS and has the little bleed hole to prevent air lock. The "piece 30" oil seals are also installed in between the engine cases and in the oil pan.
If I decide to see this through I'll need to think of something new to try, like assemble the bearing shells in the saddles, no cams, and hone them out or something.
I am not accustomed to this type of failure, something very hard to spot is going on here.

[grcamna2]

Steve,you're really going through hell with this KZ900 camshaft issue..
The cam chain may somehow be binding? I don't know  is there a way you can adjust the cam chain to a different(less)tension ? or is that preset by the tensioner ?

[Stev-o]

+1...so sorry to hear about this issue.   Take a step back and revaluate. I like Terry's suggestion about getting a second opinion if you can find a vintage bike mechanic.  Good luck hoaloha...

[MauiK3]

There is one person here I know of, I’m going to see him.
The cam chain and tensioner are pretty straight forward, much like the CB750. Not much opportunity for error there. I’ve had many theories about this problem but I’m back to oil delivery now. When the engine was apart this time I spent a lot of time looking for places the oil might be escaping to. It’s a very simple system of passages. Not much to check. I have to find something completely different that I never would expect and it may be something subtle or it may be right in front of me. I did a lot of checking for any restrictions.
The only thing I know of are the heavy head studs it has, they came with it, many run with them so they are not likely to be the problem.
I guess I’ll remove the oil pan and oil pump and try to devise an air fitting to blow air into the oil passage and see where it comes out.

[Terry in Australia]

I’m glad that you’re still thinking positively Steve, it’s easy to give up, as anyone who’s restored a bike will know. Do you still have the original shells? If so, clean them up and stick them in, and fire it up again. If it doesn’t seize, then you know that the new shells are the problem. How much oil came up to the head, a flood, or a dribble?

A NOS switch can fail, so don’t assume that it’s beyond reproach either. Good luck with it mate, we’re all rooting for you! (in the American sense, in Oz that means something entirely different…..)

[craz1]

Have you actually inspected the oil pump. And just to be sure you installed the seal between cases and the seal on the oil pump. They use the same seal which is a special seal and not just an oring. What were the readings on the plastigage when you checked clearances. I run heavy studs in all my Z1 bikes and we have used them in 2 CB750s and in my CB550. Also the Z1 oil pumps don't have issues with air locks, you still should fill the cam lobe cavities just before starting.

Remind me was that engine running when you bought it.
Did you find ANY sand at the oil pan.

[Terry in Australia]

Yep, the APE studs aren’t the issue, I’m running them in my Z1-B’s hotrod 1100cc engine with no issues.

[MauiK3]

Seals in place, they are “piece 30” in the parts book.
Plastigauge readings were on the higher end of clearance. Here’s the thing about these shells, there are no size steps so if you’re parts measure ok but the plastigauge measures out of spec or on the high end, what would a person do?
I don’t have the old shells.
I may put together a set out of my inventory, assemble them with no cams and get a bore gauge to test for roundness when assembled. If they are not round I may figure out how to hone them round. Snap gauges might work but a bore gauge or a ball gauge would be more accurate.
I’m still worried about oil delivery, I poured oil in the pockets before start up.
At any rate, the head comes off again.
Thanks all, I’d love to ride this thing but who knows, maybe I’m cursed.

[craz1]

I would really suspect that the cam caps are not original. After all you have done. I would source a known good head. May not be original but would probably take care of you problem. Again did you mount the cams in the head without valves and rotate them by hand and look for any spots that may be binding. Ive installed at least 8 sets of those shells from Z1E without issues. You should be installing them with a glove to avoid oils from your hand. Could cause problems but not like your having.
Normal clearance is .0008-.0028 or .020mm - .070mm  and max should be .16mm or .0063

Here is how Achim in Germany runs his new bearings in. You could post on the site and see what kind of answers you get. What I don't understand is you stated that they were galling. Are you depositing bearing material on to the cam journals?
http://www.kawasaki-z-classik.com/forum/viewtopic.php?f=27&t=2072&p=16078&hilit=cam+bearing#p16078

[grcamna2]

I would really suspect that the cam caps are not original. After all you have done. I would source a known good head. May not be original but would probably take care of you problem.

I can see the benefit of what you're saying.
I would hope that would be a complete head.

[Terry in Australia]

If you find another head Steve, I’ll buy your old one, I need a head for a ‘73 engine that I’m building. I’m not fussed about mismatched cam caps.

[craz1]

You should be unless you have the expertise to remachine to work. There are a few guys on the form who have used mismatched caps but had to tweak them. Beyond my pay grade.

[MauiK3]

I don't have any way of knowing if the cam caps are original.
Yes, I installed the shells with no valve gear to check free rotation.
I'll check the link out.

[PeWe]

Do not give up on this.
If oil is floading where it should but cam starve, the caps seems to be the issue as the other experienced guys writes

Not enough play or if bearings sit too loose so they can rotate and block?
Just thinking, I have no experience of diggin inside this type of engine.

I'm just back from a 270km carb adjusting ride on my K6. Finally good enough after replacing jets >100 times. Good idle, even low speed with good snappy acceleration way over the speed limits!!
Lots of brass purchased and destroyed around 3 sets of rubber float bowl gaskets.

I had this in my mind for years. Wrote down all changes with result in an Excel file. From last year my phone.
Several dyno runs which learned me when too rich and lean. Like an arrow where to go when I had done what.

On top of this 2-3 head, cylinder removals hunting oil consumption. 
Tested another cylinder and head between there with 3 cam changes within a few days.
3 setups of ported heads and cylinders last year 2021. 1005cc, 890cc to guess how much the shop should cut the 12.5:1 pistons to rideable compression. After that 970cc and 2 heads tested, oil drinking head verified and fixed.

The feeling when you win over the cursed engine will be well worth it.
Mechanic and an Excorcist?

The thing is to not rest, just continue getting your skin oiled and smooth!!

I worked from home the last +2 years which made all wrenching, rewrenching and wrenching again possible.

[Terry in Australia]

Well if you installed the cams without the valve gear and spun them over without issue Steve, I can’t see the caps being the problem? I’d do it again, drop all the valves out, oil up the shells, drop the cams back in and once again with the plugs out spin the engine on the starter to observe any issues that it might have, and see how much oil is moving in and out of the head.

Considering that the bike “Ran when parked” and all you’ve done mechanically is stripped the engine down to repaint it, there’s no reason to assume that somehow the wrong cam caps have been installed, I doubt it very much.