1981 Kawasaki GPz550: Restoration

[Cipher]

Im surprised that did not bust your crankcases or do some other sort of horrible damage.
Did you dind all the bits in the oilpan?

Are these parts still available?

Oh, so this is where you've been hanging out all these years! I applaud you for sticking with it.

Corey

When you said bigger problems I never imagined this

[roeme]

Such bad luck, but I'm learning a ton just by reading. Friend of mine own's a Z500, loads of fun.

[rphillips]

Gosh, hard to imagine such a bummer. But on the positive side, the second time around is always much easier than the first, the accumulated knowledge works wonders. May want to sit back & take a minute. Those are great little bikes, & when completed you'll have both a great bike & a whale of a story. Surely you've used up all the bad luck. Keep us updated.

[Nessism]

Damn Steve! That's some seriously bad luck there.

Keep your head up buddy! It's only money!

[srsupertrap]

Oh boy #1 exploded


Connecting rod must have bent back in Aug 2016. Both nuts came off the connecting rod bolts






Crank journal looks good but without measuring it's probably a boat anchor

[srsupertrap]

1. Removed the main oil galleries drain plug which is below the points cover
2. Turned the crank over with a ratchet by hand several times and some oil came out.
3. Then the crank jammed, figured the cam chain got jammed so removed the exhaust cam. Still jammed
4. Using two 1/4" drive as a gages



Number #1 piston is not happy

[srsupertrap]

You can learn how fast the engine can dump 4 quarts of oil on the ground. Not a good idea.

When you replaced the valve spring retainers did the shim stick up above them? Was the shim sitting on the top of the valve and not contacting the keepers?

IIRC, I checked the valve stem keepers were below the top of the valve stem tips, i.e. the valve shim was not contacting the keepers. I will of course verify when removing cams tonight . . .

4/7/17: Removed the intake cam to get a look under the buckets. If the keepers were contacting the valve shim damage would be evident. What caught my eye and hopefully yours in the first photo . . . there ain't much oil up there considering the engine ran and the oil gallery under the cam bearing cap is quite large.



Removing the buckets on the intake cam where I believed the knocking noise was coming. The valve stems are not damaged and valve keepers are in place. NOTE: Look at 2 & 3 valve retainers you will see where the machinist milled off the top of the valve spring retainers. Ok, that makes me feel better but doesn't solve anything. Back to August 2016, what other damage could have occurred when #1 piston chewed the spark plug electrode?

Could the connecting rod bend? Second why isn't there any oil up in the cylinder head galleries . . . the GS has a big pool? From the previous page, I also heard some mechanical noise when shutting the engine off ( Chink, chink . . .). Clearly not a valve keeper.

Looks like this is more than just removing the Head & Cylinder

[Nessism]

Sounds like a stupid idea but can I learn anything from running it with the valve cover removed?

You can learn how fast the engine can dump 4 quarts of oil on the ground. Not a good idea.

When you replaced the valve spring retainers did the shim stick up above them? Was the shim sitting on the top of the valve and not contacting the keepers?

[srsupertrap]

I am speculating a lot and not having a lot of experience with motorcycle engines which make loud knock noises take anything I say with a grain of salt. I pulled the valve cover and measured the GPz550 valve clearance. Expecting real bad considering the engine knock but measurements look correct. Recall I had a machinist remove material from the valve stem tips, the 11/12 date shows valve clearance after it was reassembled. The 4/5 date shows the measurements after starting this weekend and said knocking noise.

After checking valve lash, I noticed the intake cam oil galleries did not have any oil in them. The exhaust cam galleries did. I removed the spark plugs, turned the engine over roughly 20X by hand, saw the oil level in the sight glass drop but no additional oil up in intake cam oil galleries. I would suspect the oil pump is working if the oil level drops while turning the engine over but not having oil circulating could certainly explain a knock noise right . . .

GPz550 Valve Clearance
Date: 11/12/16	Cyl 1	Cyl 2	Cyl 3	Cyl 4
In .004-.008	0.009	0.007	0.008	0.008
Ex .006-.01	0.01	0.011	0.01	0.011
Date: 4/5/17	Cyl 1	Cyl 2	Cyl 3	Cyl 4
In .004-.008	0.008	0.005	0.007	0.009
Ex .006-.01	0.008	0.008	0.007	0.01

[srsupertrap]

Checked & rechecked items on Saturday including Static timing, compression check, piston location, verified Dyna S wiring was correct, coil wiring was correct nothing reversed etc. The compression check albeit low was consistent across cylinder 1-4. Then I recalled when reinstalling, the Yosh pipe in February one fibe exhaust gasket OD was too large. I made it fit by unwrapping several windings from the OD, trimmed the excess, reinstalled thinking I was good which led me to believe Saturday night maybe all I had was an exhaust leak.

Sunday I tightened up the exhaust system bolts, started it and was greeted with a loud knocking noise from the intake cam which is a different than the exhaust leak. Sounded like excess valve lash with a running clearance of .25" (exaggerating). Recall I went to all the trouble of grinding valve stems (.50mm to .70mm) max to correct the valve lash and bench shimmed the head etc. What I can share is the machinist from Iowa milled off material from the top of the several valve spring retainers but didn't increase the counter bore depth. With the valve shims installed in the retainer several shims actually rocked back and forth (red X) and one shim once installed could not be removed. To alleviate that situation I replaced those valve spring retainers with EBay KZ550 un-machined valve spring retainers, the rocking valve shims went away and the shims could be easily installed & replaced. Apparently some valve stems were no longer contacting the valve shim. That's the only thing I can deduce. I think I heard a valve spring keeper came loose but won't know till I open it up . . . again


4/4: I pulled the valve cover tonight. I turned the engine over by hand, no mechanical interference felt & crank resistance seems normal. Cam sprocket bolts installed and have not moved. Checked valve lash on 3 & 4 Intake which measured .009" & .008" respectively which is were I set them. I will check rest Wed.
Sounds like a stupid idea but can I learn anything from running it with the valve cover removed?

No good answer that I can think of. Do you think it is possible that the crank through moved when the piston hit the ceramic? Long shot. You could possibly check for this with a dial indicator in the spark plug holes, comparing distance to the pistons at indicated top dead center. If they are not all the same, that would be a good indication that all isn't well.

[srsupertrap]

With the help of Scott, my neighbor the GPz is back in the garage


Ray came over Sunday, we started it and immediately noise came from the #1 cylinder. Ray characterized as misfiring or incorrectly timed I thought it was similar to noise when it ate the spark plug electrode in August . . . it ran a whole 5 seconds maximum before I shut her down.

We didn't see much value in starting it up again. Scratching our heads Ray suggested perhaps a valve was stuck but we ruled that out. Ray suggested perhaps the wires to the coils were reversed and it was firing 180 degrees out. I jumped on that idea because I was not looking to disassemble this thing yet again and was hopeful for an easy fix.

I ruled that out pretty quick by reviewing the wiring diagram & photo of Coil 1-4 below when it was disassembled back in Dec 2013. The Yellow/Red is the switched power going to both coils, the black wire going to the bottom of the coil indicates it's Coil 1-4. The green wire goes to Coil 2-3 and plug wires go to correct cylinders. . . I verified that was correct.



The culprit could be the Dyna S wiring i.e. switched. I took several picture in 2014 but couldn't tell which wire of the Dyna S was installed in the 4 position connector (Kawasaki Wiring Description). Below is the Dyna S which is a bit confusing because Dynatek shows a Black wire going to Coil 1-4. In reality 1-4 is the pick up on the left side which I redlined, it's a White wire which has a heat shrinked black sleeve on it. Conversely 2-3 is the right side pick up which I also redlined. The 2-3 is a black wire which has a heat shrinked green sleeve on it.

Glad you're following because back in August I installed a new connector to eliminate the PO jury rig. The index card wiring below reflects the wiring which goes to the 4 position connector which I believe is on Page 30 +/- page. The rectangular symbols represent the heat shrink. The wires from the bottom represent the Dyna S wiring. That being said it looks correct to me.



I will have to perform a static timing check per Dynatek's recommendation to determine if I have correct spark to the right cylinder. Just to throw another variable into the mix, I performed the static timing test back in August and with the #4 spark plug removed, grounded to the cylinder head nut I saw it spark.

We also turned over the engine with spark plugs installed and the plug wires removed from the spark plugs. That sounded completely normal. . So the noise is attributable to firing, compression, mechanical damage or other. Feel free to ask questions or comment on what could cause the noise Ray (Ghostgs1) & I heard.

Sure Steve, this weekend?