Author Topic: Maui Z1 1973 (Read 47463 times)

MauiK3 · « **Reply #700 on:** December 28, 2021, 07:29:32 AM »

Ugh
A cam bearing spun. I took the head off to inspect everything. Now I have to figure out why. I'm going to try to blow air up from where the oil pump mounts to make sure it comes out where it should. No sign of any other damage, nothing ugly in the oil pan. Lots of things to check.
I'm even thinking of removing the valves and springs so I can assemble all the cam bearings, cams, and caps to see if it all spins well.

grcamna2 · « **Reply #701 on:** December 28, 2021, 11:31:10 AM »

Quote from: MauiK3 on December 28, 2021, 07:29:32 AM

Ugh
A cam bearing spun. I took the head off to inspect everything. Now I have to figure out why. I'm going to try to blow air up from where the oil pump mounts to make sure it comes out where it should. No sign of any other damage, nothing ugly in the oil pan. Lots of things to check.
I'm even thinking of removing the valves and springs so I can assemble all the cam bearings, cams, and caps to see if it all spins well.

I see,possibly a lack of oil pressure to that cam journal?

PeWe · « **Reply #702 on:** December 28, 2021, 12:49:14 PM »

Oil pump priming/air bubble issue?
Or blocked oilpassage to head/cam?

MauiK3 · « **Reply #703 on:** December 28, 2021, 01:20:57 PM »

I’m going to be investigating all that. Pretty discouraging. I may order extra head gaskets so I can assemble and test flow before the valve gear goes in. The head was very, very clean, these oil passages are pretty easy to blow out. I know they’ve been in use for a long time but this motor has HD head studs which restrict the annular space. Just thinking out loud. Good thing I’m not in a hurry.

Terry in Australia · « **Reply #704 on:** December 28, 2021, 04:10:25 PM »

I wouldn't worry about H/D studs Steve, thousands of Z1's were drag raced over many years with H/D studs, with only positive benefits. I have H/D top and bottom studs in both of my hotrod Z engines, but as yet I haven't fired them up. Did you use a sealant on your base and head gaskets? If you used too much you theoretically may have restricted oil flow? I presume that there was no scratches or burring of the bearing surfaces on the cam that the bearing spun on? Are the cam bearings new, or used? I used the used ones that came with the head I bought and there's probably a tad of wear in them, but I'm not worried, after riding Suzuki GS1000's for years and thousands of miles, I learned long ago that slightly worn cam bearings don't hurt anything. I'm looking forward to seeing some pics.

Stev-o · « **Reply #705 on:** December 29, 2021, 08:39:40 AM »

Quote from: MauiK3 on December 28, 2021, 07:29:32 AM

Ugh
A cam bearing spun.

Sorry to hear this. Did it come to you with the spun bearing?

MauiK3 · « **Reply #706 on:** December 29, 2021, 02:00:34 PM »

I put in new bearings. This may not be an altogether new problem. When I took it apart the 1-2 side of the head had a few wear indications. Now I need to assume there is an oil delivery problem to the 1-2 side or maybe the whole head. I will be taking the cylinders off and trying to see what I can find out. I may put together an air gun set up to blow up from the oil pump connection. I didn’t use any sealants anywhere except the two engine halves, a very thin (see through) coating, there was no squeeze out.
The cam is toast but I happen to have another hollow cam. The cam actually measures ok, I may see if the local machine shop could polish it up but I have doubts it would be within the service limit.
This certainly is discouraging.

Terry in Australia · « **Reply #707 on:** December 29, 2021, 09:42:52 PM »

Fcuking hell Steve, that bearing is screwed! I wondered if maybe the cam was slightly bent? The bearing surface on the cam doesn't look that bad in the pic, so to do that damage, something bad is going on. Take the bad cam to the shop and have them seit it up between two centres and see if it's true? Get them to check your replacement cam while you're at it. If they're both straight, get them to polish the bearing surfaces for sure.

PeWe · « **Reply #708 on:** December 30, 2021, 06:29:49 AM »

You'll hopefully find where the oil is blocked so you can ride in piece when fixed.

This is a nightmare to get, often mentioned on the forum.

I have noticed that dirt can fall off when removing the top end.
Fiber gaskets have often burrs around its holes.

Oil studs must be off or completely covered when painting the crank case. Especially where oil feed to head.
At my last assembly a small piece of silicone had entered one cam holder oiling hole. Creeping in like a 7mm long, 1mm thick worm.
Only way was when I took it apart. It was under the rubber pucks.
I blew all holes with compressed air and used drive chain cleaner spray inside those holes and a thin steel wire. Removed the oil restrictors in head before.

Assembly lube give longer time to run without oilpressure, no oil to cam.

This will hopefully end up in something to improve that you have not seen before so this sad incident has a value.

Soon new year, 2022 with new rides to enjoy.

ekpent · « **Reply #709 on:** December 30, 2021, 04:54:46 PM »

Sorry if I have not totally been keeping up Steve but if I remember you had it running before the tear down. Has it actually run with gas since its been put back together or is that from just spinning over the engine with the starter getting oil pressure up and other things ? Must have missed a fire up with that kind of damage. Sorry to see you having to deal with that. The bike was really coming along well but sure you will get it sorted. Eric

MauiK3 · « **Reply #710 on:** December 31, 2021, 07:15:37 AM »

I'm working through all the possibilities, yes, it ran for a bit which is why there is so much damage.
Stripped the head yesterday so I can check new bearings when they arrive.

MauiK3 · « **Reply #711 on:** December 31, 2021, 01:35:34 PM »

Just a what if question.
Stock cams for early Z1’s are not easy to find, I suppose a damaged one could be welded and machined…..maybe. So if a guy wanted an aftermarket cam set that was essentially stock, is there a widely accepted brand? Just wondering, I have a working set of cams but I’m always thinking about “what if”

Terry in Australia · « **Reply #712 on:** December 31, 2021, 08:37:59 PM »

I think my cams are GPZ1100 items Steve, but Megacycle's 470/05's are what you need for a stock engine, they're drop in cams, so no need to degree them. Like my Andrews CB750 cam, they're probably stock lift so no need for stronger springs, with a little more duration for some extra midrange torque.

https://megacyclecams.com/catalog/catalog.pdf

craz1 · « **Reply #713 on:** January 01, 2022, 08:33:03 AM »

When you get those bearings check the clearance with plastigage along with checking runout on the replacement cam, you will need to pull the valves but may be worthwhile. I have replaced those bearings on many engines without checking the clearance with no issues. If you cant find the hollow cam just use any from 74 on up through the KZ900. I have several sets of cams sitting here and a friend of mine has several sets of 73 hollow cams. If you must have the hollow cams PM me. I believe there was a problem with the hollow cams breaking and Kawasaki went to solid.

Im assuming you have been using assembly lube and not just oil doing your build right.

MauiK3 · « **Reply #714 on:** January 01, 2022, 08:39:25 AM »

Assembly lube all the way. That stuff is pretty sticky.
Waiting on my bearings now, valves are out of the head.
Hopefully it will all come together as it should.

grcamna2 · « **Reply #715 on:** January 01, 2022, 10:46:35 AM »

Quote from: craz1 on January 01, 2022, 08:33:03 AM

When you get those bearings check the clearance with plastigage along with checking runout on the replacement cam, you will need to pull the valves but may be worthwhile. I have replaced those bearings on many engines without checking the clearance with no issues. If you cant find the hollow cam just use any from 74 on up through the KZ900. I have several sets of cams sitting here and a friend of mine has several sets of 73 hollow cams. If you must have the hollow cams PM me. I believe there was a problem with the hollow cams breaking and Kawasaki went to solid.

Im assuming you have been using assembly lube and not just oil doing your build right.

+1 on checking the runout/'true'ness of your camshaft.

craz1 · « **Reply #716 on:** January 02, 2022, 09:38:18 AM »

Also are you sure you got all the grit from blasting out of that engine.

grcamna2 · « **Reply #717 on:** January 02, 2022, 11:09:25 AM »

Quote from: craz1 on January 02, 2022, 09:38:18 AM

Also are you sure you got all the grit from blasting out of that engine.

The damage to the camshaft and bearings really does look like it had abrasives in it..

MauiK3 · « **Reply #718 on:** January 03, 2022, 06:08:05 PM »

I just heard from the Oahu shop working on the fuel tank and paint. He reports it will be ready for paint next week. No photos yet. I’m really hoping this works out, if it does the bike will have the original tank on it.
Parts still coming for engine work.

Alan F. · « **Reply #719 on:** January 03, 2022, 07:03:49 PM »

Good news!

RAFster122s · « **Reply #720 on:** January 03, 2022, 08:23:45 PM »

Incredible...

Terry in Australia · « **Reply #721 on:** January 04, 2022, 04:55:33 PM »

Double check to make sure it's the same tank, if it is, that guy is a miracle worker!

RAFster122s · « **Reply #722 on:** January 04, 2022, 10:41:49 PM »

I bet he replaced a lot of metal rather than trying to reshape all that damage to the tank. Even so, he is skilled metalsmith to roll the curves to match everything to the tank. Godfrey does custom tank work blending two different tanks or stretching capacity or grafting in fuel pumps or similar kinds of things. It takes some pretty incredible skills to save a tank like that…

Terry in Australia · « **Reply #723 on:** January 05, 2022, 02:54:37 AM »

I know a guy who had a badly damaged very early K0 "Wrinkle" tank. The "Wrinkle" part of the tank is in the bottom section, and it was undamaged, so he cut a K2 tank in half and welded the top half to the K0 "Wrinkle" bottom. He wasn't doing it to sell or to deceive anyone, he needed the correct tank for his sandcast.

MauiK3 · « **Reply #724 on:** January 08, 2022, 01:37:16 PM »

While waiting for parts I checked my cam runout using my wheel truing stand, worked great. Cams checked out straight. I had to drill more holes in the stand to set the bearings the right distance apart.

News:

Author Topic: Maui Z1 1973 (Read 47463 times)