Kawasaki Z500 B2 1980 refurb after 78260 miles

[linuxrob]

Forgot to post a few pics as i got the motor out and the jack and supports i used.

Gave the engine a good washdown and degrease. Drained oil and removed filter.

 

To stop any damage to the Motad exhaust some padding was needed, a bit over the top but did the job

 

With the engine brackets on right side, carbs, coils chain and electrics removed a jack was placed under the sump padded with wood and timber placed at the height just above the frame on a trolly. Lift motor up a few inches to clear the brackets tilt to thr left to clear sump and pull out to the right onto the trolly. Reverse to install. Piece of cake with 2 people.

Rob

[linuxrob]

With the engine now on the bench i can get on with the top end.

off with the rocker cover

 

Tappets measured, last time this was done was at 66000 miles should have been done sooner.

Spec

inlet 0.10 - 0.20 mm

Exh 0.15 - 0.25 mm

You MUST use the Factory workshop manual procedure on these as using any other meathod i.e. Clymer manuals etc will give incorrect results.

Basically this:

With cyl 1 @ at TDC of the power stroke, measure the clearance on intakes 1 and 3.

With cyl 2 @ at TDC of the power stroke, measure the clearance on exhaust 2 and 4.

With cyl 3 @ at TDC of the power stroke, measure the clearance on exhaust 1 and 3.

With cyl 4 @ at TDC of the power stroke, measure the clearance on intakes 2 and 4.

my results:

No 1 Inlet = 0.10 mm

No 2 Inlet = 0.12 mm

No 3 Inlet = 0.13 mm

No 4 Inlet = 0.09 mm Nearly!!!

No 1 Exh = 0.18 mm

No 2 Exh = 0.19 mm

No 3 Exh = 0.15 mm

No 4 Exh = 0.19 mm

All in the tight end but accepable, I try to get them about the middle.

With the engine set back to No1 TDC I removed the cam chain tensioner and all the camcaps then took both cams out.

m6 and m8 nuts removed and head off.

Rob B

[linuxrob]

With the head now off, I got out the trusty valve spring compressor that I have used since the Honda SS50 days. The 2 prongs on the business end are a little close together for the Z500 valve caps, so when I did these valves last in 1983 I bent them out a mill or so. It is still a bit of a fiddle to get them on square for removal and even more fiddly to put the collets back. This time I have a lovely magnet from an old hard drive, a rare earth magnet and very strong so making the safe removal of collets a lot easier.

 

 

I use my smaller less powerful pen magnet to draw out the buckets with the shim underneath and into the numbered section of my large eggbox. All valves and springs removed, placed in numbered parts of the egg box in less than 10 minutes.

 

 

Well they all looked pretty yuk, here is just the ones from No 1 cylinder, the rest were the same. How these passed the light oil sepage test is a bit of a suprise.

 

 

You can see from the close-up below of the inlet valve these mating sufaces are not good, also it will be no suprise to learn that the valve guides are well worn. The wiggle test was carried out as I do not have a small bore guage. The valves themselves are well within spec after measureing them in the 3 places required with the 0-25mm micrometer.

Spec:

Wear limit - Inlet 5.41mm, Exh 5.39mm

all valve- Inlet 5.47mm, Exh 5.43mm

 

 

Those marks you can see are pitting not carbon. I am still only going to use fine paste the metal polish to grinde them in.

till next time

rob B

[fastbob]

Looking good , those seats look like they have sufficient width so a light lapping should be fine .

[linuxrob]

Cheers Bob, just a little spoiler.

Took my time and got these results with fine paste and oil. Will finish the rest them pop the valves back in for a liquid and compresses air check. The valve guides are very near scrap with the wobble test. The only option is to get bronze guides from somwhere.

Rob B

[linuxrob]

Decided to make a cylinder head stand, used wood as still have some bits of my old gate left.

Basically I wanted to have the head raised up from the bench and enough clearance to get the valves in and out plus valve spring compressor in without having to balance the thing on blocks. Seen a few on youtube like a "V" shape in metal but I made just a vertical stand. The wood is a bit thick, made a "H" shape using the head gasket as a template and also marked out the holes for the studs.

 

 

Have a dozen 8mm coach bolt 200mm long left in my bolt draw and using my drill press made 8 holes. 8.5mm wide. I used the center 4 holes and 4 outside holes of the head. Fitted the bolts with the head gasket keeping them aligned and tightened them down.

 

Ran 2 M8 nuts down each stud then 1 x M8 steel washer and 1 x M10 copper washer to approx the depth to give me a full nut sticking out the 4 outside head mounts. Copper washers of course to prevent any scoring of the Aluminium head, hand tight to stop any distortion.

 

even supports the head upside down for combustion chamber cleaning and valve lapping.

 

Good result. Now to get on with some work.

Rob B

[linuxrob]

Well finally got on with the jobs to do. Cylinder Head Clean and Blasting.

The easiest (costly) option was to send it with the cases barrel etc to Tiger blast nr York for vapour blasting but being a stubborn bugger and wanting to do as much as possible myself, besides the weather is rubbish and nothing on the telly.

 

 

Before blasting the head was washed with small tooth brushes in diesel and then with scotchbrite in hot soapy water, after drying it off with the air line used 2 coats of paint stripper, then washed 2 more times and airline dried. The combustion chambers were blasted with soda and came up great. The remaining paint had to blasted with the fine black grit I got from the media suppliers in Newton Aycliffe. Had to be very careful not to go anywhere near the bearing surfaces but even plugging a lot of it up the blast media went everywhere.

 

 

After blasting and blowing out with the airline the whole head was washed in diesel then in hot soapy water. A further wash with my power washer was followed by hot clean water and a dry with the airline. It is also imperative the you re-oil the valve guides after each wash, they will flash rust.

 

A further power wash and hot water rinse was carried out followed by 2 more brush washes and power wash until no more debris was left in the bottom of the bowl. It pays to keep washing and rinsing, the power washer set to a needle spray down the oil ways was great but I ended up very wet.

 

 

When it comes to my spare head, or any other for that matter I will plug and mask everything. The soda is no problem as it dissolves in water but this fine grit was a real pain to get out. I suppose a large hot ultrasonic tank would be a good idea but for me impractical and way over budget (see comment at the start of this post).

Painting next

Rob B

[linuxrob]

Nov 27th update, better late than never

I got the heater on in the shed and used up the last of my Satin Black paint on the cylinder head. The masking and etch priming was done a few days ago so was ready to apply some colour.

Masked primed and bottom coated with Satin Black, this is an old can of Wilko's Satin Black enamel.

Below with a just a mist coat of black, old bolts and exhaust studs screwed in and old head gasket used.

 

 

Mist coat dried followed by a medium wet coat and 2 wet coats. left to dry then turned over.

 

 

This is where my can ran out. Will let is harden and have a close look at the finnish and decide if Wilko's Satin black is to used to finish off the head and then the barrel.

While we're here this is my shed as I was preparing for today's painting with the GS125 outside in the cold.

 

Finally, yours truly in suitable attire.

 

Rob B

[Guest Richzx6r]

So its coming along slowly then good to see you are taking the time and doing a proper job on it

[linuxrob]

So its coming along slowly then good to see you are taking the time and doing a proper job on it

Cheers, will post more v soon

Rob

[linuxrob]

After a good Christmas break it's back to the shed.

Left the lacquer to harden before final check, clean and rebuild.

 

Very pleased with the job so far, this my spare head with valve guides just in spec. Got the number of a local guy to make up some Phosphor Bronze guides for the original head.

No 2 Combustion chamber before

 

No 2 Combustion chamber after

 

You can see that soda blasting makes short work of getting rid of the carbon deposits.

Valves lightly ground in, fitted with springs just compressed then tested with water in the inlet and exhaust and air line blown around the valve face, no bubbles, lovely.

At this point I checked the seals and gasket box and I had not ordered any Valve stem seals. MPS (https://www.motorcyclespareparts.eu/en) had a 10% offer so ordered the seals, 2 engine bolts and some rear sprocket tab washers (the Z500 rear sprocket is held on with 4 bolts not 6 as with the 550).

So while I wait will have to find another job to get on with

In the meantime here is the measurements relating to the valves.

 

 

You can see the valve heights are all well within spec, should hope so as they have only ever had a light grind in.

The only thing to look at is the No 3 Exh valve and No 1 and 4 Inlet clearance, will look through my shim collection to get them in the middle of the recommended settings.

Till next time...

[linuxrob]

Valves ready for installation.

 

 

More time in the shed this week. Seals arrived in a few days, nice quick post from Europe.

Here you can see the difference between OEM seals and pattern ones. The Kawasaki part number is: 92049-1153 which replaced the earlier part number 92049-1050 both these seals have the following dimensions 5.5 X 12 X 6 X 9.8mm. The pattern seals have a hole for the valve at 6.0mm, so oversize. The old seals are from a pattern gasket set I bought 4 years ago, a Vesrah one but still the seals are not correct. Always use OEM seals and head gaskets.

 

 

After a good whizz round with a alcohol soaked rag the head was placed on the stand and the new seals greased with Red Rubber Grease.

 

 

Located with the paint brush (non brush end obviously).

 

 

and pushed on

 

 

Valve oiled and inserted from below.

 

 

Springs, top retainer in, springs compressed and collets fitted.

 

 

Before unscrewing the spring compressor I find it a good idea to place some cloth over the collets to stop them pinging out.

 

 

The other 7 valves were fitted in the same way.

 

 

Head was now covered in bubble wrap and stored out of the way. The Exhaust studs and inlet boots will be done last to avoid damage (to me if not them)

Exhaust studs are with the rest of the bolts in the to zinc plating que.

Pistons off next

[fastbob]

This becoming a restoration masterclass .

[linuxrob]

Cheers Bob, this is the first time i have been able to fully document a full strip and rebuild. I have had many a bike in bits over the last 40 odd years and it is good to record all the jobs. Did a small thread on my Bandit 53000 mile tidy up a few years back, will repost it here I think.

Rob B

[Guest Richzx6r]

Seeing all this I'm tempted to strip my old ninja and give it a good refresh not sure I'd be able to document it as well as you are though

[linuxrob]

Barrels next

First job was to make sure my micrometer as reading OK, so out with the std 50mm bar and:-

 

Perfect

 

From Fig H49 in the manual (see above) Measurement are taken in 3 places, Top (10mm down bore), Middle (40mm down bore) and Bottom (10mm in from base of bore, unworn part). Both front to back and side to side measurements are taken at the above places to check for an oval bore.

 

 

Above is No 2 cylinder bore marks, the worst bore and No 4 side to side bottom measurement showing 55.01mm.

 

Then i mic'd the pistons and gudgeon pins

 

 

After making sure that the pistons – rings and bores were within spec and round enough it was time to prep for painting. I decided to just use soda blasting to clean the flaking paint and oxide build up as :-

A: The more aggressive media took an age to clean out of the head.

B: I did not want to accidentally blast he cylinder bore surfaces.

It took about 2 hours to get enough of the paint off to have a good keyed surface.

A good wash in hot soapy water, final clean hot water rinse and blow dry with the airline was followed by a smear of thick gear oil on the bores to prevent flash rusting.

 

 

Painting next

[linuxrob]

painting now done and quite a lot of things done as nowhere to go.

 

 

Also used my cheap draper honing stones to deglaze

 

 

Soda blasted the pistons

 

 

 

rings fitted

 

 

dressed up all my good old cross head bolts finished plating them and added them to the finished bottom end

 

 

loving this good weather.

Rob B

[linuxrob]

Kawasaki have there own tool to keep the pistons supported and level while fitting the barrels. Basically bent wire that fits under the piston skirt.

 

 

In the past with the aid of my dad, fitting pistons 2 – 3 then 1 – 4 was made easier by stuffing more lint free rags into the crankcase holes as a support. Always had 100% success. Now Dad no longer with us I have need the pistons firmly supported.

My first Idea was to copy the Kawasaki tools but have not got the right gauge wire, so in the absence of aluminium plate or even suitable chunks of plastic to make a tuning fork shaped support I opted for plain kitchen sponges under the pistons. This was OK but in crease the stability I cut some 2 strips of hardboard to to lay over the mouth of the crankcase then wedge sponge round the pistons.

 

 

When the new oil seals turn up Barrels on

Rob b

[linuxrob]

Waiting for new oil seals for the barrel so took the back end apart again and replating the bolts this time with the proprietary chemicals and making them really shiny.

So far done the disc bolts and sprocket nuts and bolts and half the spindles. Also did the nuts for the inner tube / tyre securing bolts.

here is the wheel bits bolted back on

[linuxrob]

Finally my oil seals arrived:

Anyone with a Z550 or GPZ or maybe any Z from this era and possibly onward when you are cleaning the crankcases, blasting or otherwise, make sure you check the part list diagrams for small "o"rings if a couple of your head stubs are NOT blind drilled and tapped holes.

On the Z500/550 series there are 2 studs drilled and tapped through into the upper crankcase. They have each a small 8mm "O" Ring fitted, they No 3 on the part diagram. Part No 670D1508. not to be confused with the 2 oil redistrictor "O" Rings for the barrel No 10, part No 92055 - 101 now replaced by part No 670D2010

 

 

 

 

this was the state of mine

The rear on was OK

 

The front was split so I ordered and replaced both.

I nearly forgot to fit these little buggers before the new base, Phew!!

using my sponges as Piston supports the old pistons and rings went in with the minimum of fuss.

 

 

Final job for the day was new "O" Rings later oil restrictors and head back on

 

All bolts torqued up. Tea Time.

Rob B

[linuxrob]

Engine finally back in

[Ian Frog]

That is looking really good.

Credit to you and cant wait to see it finished.

Like the "Blue Plaque" by the way

Cheers

Ian

[linuxrob]

That is looking really good.

Credit to you and cant wait to see it finished.

Like the "Blue Plaque" by the way

Cheers

Ian

 

Many thanks Ian, should really blur out that Plaque, gives too much away. Made my better half as this is how i refer to this house.

In 2016 when i took it off the road I thought that there was plenty of time to take it to bits, clean it up, pop it back together. Winter 82 -83 when it was last in bits it took only a few months to strip clean and rebuild. We both are a lot older now and even though I have a better shed I have slowed down more than I imagined.

It's 40th birthday in 1st August this year and that is pushing me to get it done, at least so I can pose it on the front and take an updated pic in the same place it stood when my first "on the road" pic was taken. See first page of this thread.

Regards

Rob B

[fastbob]

Absolutely stunning . It makes my previous attempts at restoration look like something from Wheeler Dealers !

[linuxrob]

Much appreciated Bob, This bike has been with me Man and Boy and has quite a few battle scars. Have kept them all as it is part of our history. Have seen bike where the history has been for want of a bitter word "reset".

found a video on YouTube of the Durham dales run 2008, low and behold a short clip of muggins here, took a screen for the album

 

Wheeler Dealers indeed!! Have seen you posts and they are top quality as are all on here. It is a joy to see us all enjoying our bikes in every way we can.

Rob