[Howitzer69]

Case scrubbing time... a toothbrush and parts solvent.

Kevin Bergeron says one should only use the blue "Scotch Brite" scrubbing pads on the gasket surface (he says the green Scotch Brite pads will scratch up the naming surface and shouldn't be used).

Comments anyone?

We also have an oil seal that doesn't seem easy to remove, I don't want to marr up the seal housing on the case... I know there are seal pullers one could use.

 

[WFO-KZ]

Looking great! I have never used scotchbrite on a gasket surface, let us know how it works out. I have used normal, steel gasket scrapers but you have to be super careful, or plastic scrapers. Permatex makes a gasket remover spray, but it is not good to breathe and not good on plastic or rubber parts.

I have a set of bushings designed for pushing out bearings or oil seals but sometimes you can find a socket that fits perfectly. You can try heating the aluminum around the seal with a hair dryer. The aluminum will expand faster than the steel band inside the seal. But really, if you get the right size socket or bushing, you ought to be able to push or tap it out with no heat. Some people will pry it out with a screwdriver but you do have to be careful not to damage the aluminum bore. Save all seals and bearings as you made need their part numbers to get replacements.

Be aware however that bearings come in different classes of fits and this is not normally part of the number that appears on the bearing.

 

[Howitzer69]

Looking great! I have never used scotchbrite on a gasket surface, let us know how it works out. I have used normal, steel gasket scrapers but you have to be super careful, or plastic scrapers. Permatex makes a gasket remover spray, but it is not good to breathe and not good on plastic or rubber parts.

Would steel wool be too harsh on the aluminum? I would think a steel wire wheel on the bench grinder would be a no-no eh?

I have a set of bushings designed for pushing out bearings or oil seals but sometimes you can find a socket that fits perfectly. You can try heating the aluminum around the seal with a hair dryer. The aluminum will expand faster than the steel band inside the seal. But really, if you get the right size socket or bushing, you ought to be able to push or tap it out with no heat. Some people will pry it out with a screwdriver but you do have to be careful not to damage the aluminum bore. Save all seals and bearings as you made need their part numbers to get replacements.

I was thinking about using a socket to tap the seal out, but I'm going to wait until I have a replacement before I try to remove the old one (so I know how the seal looks). It's tough to see which part is the seal and which part is the aluminum case housing.

Be aware however that bearings come in different classes of fits and this is not normally part of the number that appears on the bearing.

I bought the two crankshaft bearings locally but now I'm wondering if they are the correct ones. They are a C3 clearance bearing, the replacement bearing offered by Partzilla appears to be a C3 bearing too (the pictured bearing has a C3 number stamped on it). The bearings I bought are sealed bearings (I'm told the plastic rings can be removed).

Thoughts?

 

[1981GPZ550]

Steel wool and steel wire brushes are a poor choice for cleaning any aluminum. They leave behind small unseen bits of steel which will promote galvanic corrosion.

 

[Howitzer69]

Steel wool and steel wire brushes are a poor choice for cleaning any aluminum. They leave behind small unseen bits of steel which will promote galvanic corrosion.

Ok, good to know. Thanks for the tip, what technique/method would you advise?

 

[WFO-KZ]

I agree with GPZ550. I would not use steel wool.

Gasket scraping is a labour of love. It takes time and patience if the gasket is stuck like glue. In many instances like on valve covers, we just don't have much choice, but in your situation here is something you could try:

Buy your wife a brand new cookie sheet and "borrow" one of her old ones. Pour about 1/4" of varsol or similar solvent into the sheet and then lay the gasket surface down and let it soak for a day or two to see if it has softened the gasket, making it easier to remove. If that does not work try the same process but with very hot water.

I don't see a recent picture of the bearing you removed, but recall that your cases were split by someone else so you cannot be sure that these are original bearings. Having said that, the C3 is probably fine. Does your manual give you any guidance? The generic example below would indicate C4 but you would probably be ok with C3 and yes the shields can be removed.

 

[1981GPZ550]

With patience and practice a single edge razor blade is your friend when it comes to gasket removal. Also anaerobic sealers are very effective. If you find imperfections on the mating surfaces sandpaper on a large sheet of glass can clean and dress the parts in question. Again I stress the need for post repair pressure test. Looks like you are making substantial progress. Kawasaki used that engine extensively and all were wonderful little motorcycles. Sadly I am old enough to remember uncrating, assembling and doing pre delivery on countless examples. How I miss the old days of simple honest motorcycles. You have a gem.

 

[Howitzer69]

On another note, we just discovered that we are missing the entire muffler assembly (muffler, muffler cover, baffle tube).... grrrrrr....

My brother thinks he might have tossed the parts into one of his many scrap metal piles at the farm, now under a snowbank until spring... hopefully it turns up. I did find a couple possible leads on eBay but the shipping is a killer (big unique-shaped part I guess).

 

[Howitzer69]

With patience and practice a single edge razor blade is your friend when it comes to gasket removal. Also anaerobic sealers are very effective. If you find imperfections on the mating surfaces sandpaper on a large sheet of glass can clean and dress the parts in question. Again I stress the need for post repair pressure test. Looks like you are making substantial progress. Kawasaki used that engine extensively and all were wonderful little motorcycles. Sadly I am old enough to remember uncrating, assembling and doing pre delivery on countless examples. How I miss the old days of simple honest motorcycles. You have a gem.

Maybe a razor blade will do the trick.

 

[Howitzer69]

I agree with GPZ550. I would not use steel wool.

Gasket scraping is a labour of love. It takes time and patience if the gasket is stuck like glue. In many instances like on valve covers, we just don't have much choice, but in your situation here is something you could try:

Buy your wife a brand new cookie sheet and "borrow" one of her old ones. Pour about 1/4" of varsol or similar solvent into the sheet and then lay the gasket surface down and let it soak for a day or two to see if it has softened the gasket, making it easier to remove. If that does not work try the same process but with very hot water.

I don't see a recent picture of the bearing you removed, but recall that your cases were split by someone else so you cannot be sure that these are original bearings. Having said that, the C3 is probably fine. Does your manual give you any guidance? The generic example below would indicate C4 but you would probably be ok with C3 and yes the shields can be removed.
View attachment 42650

We do have the majority of the gaskets removed, it's just the remnants that are still visible (heck you can't even feel the remnants)...

Like you said, we could soak the case's gasket surface in a layer of parts solvent.

 

[Howitzer69]

I don't see a recent picture of the bearing you removed, but recall that your cases were split by someone else so you cannot be sure that these are original bearings. Having said that, the C3 is probably fine. Does your manual give you any guidance? The generic example below would indicate C4 but you would probably be ok with C3 and yes the shields can be removed.
View attachment 42650

I will do some reading in my Clymer service manual.

 

[Howitzer69]

More progress:

We decided to open up the carb:

Needs some TLC and elbow grease... comments? A large amount of chalky crap to clean out... vinegar maybe?

The newly purchased carb kit is definitely needed.

Removed the float, jets, needles, etc... used some carb cleaner, more cleaning to go.

 

[WFO-KZ]

Soaking in carb cleaner is a good start. If you have access to an ultrasonic bath cleaner, they are awesome.

 

[WFO-KZ]

Here is a short video explaining how ultrasonic cleaners work. The microscopic bubbles will form everywhere including deep inside small places that a brush cannot reach.

 

[Howitzer69]

I've just dropped off the following at a local engine head/cylinder rebuild shop:
1. The cylinder - I was told it looks ok and just needs to be unglazed/cleaned up.
2. The head - I was told it will be checked to see if it's flat. It will also be cleaned up.
3. Piston with old rings installed. I was told it is oversized (I was shown that this is stamped on the piston). I was told they will get new rings to use with my old piston.
4. Crankshaft and rebuild kit. I was told these parts will be sent out for the crank to be rebuilt and balanced. I was thinking of just sending the crank and kit to a rebuild shop myself but I decided screw it - let this shop send it out.

Comments anyone?

 

[Howitzer69]

Here is a short video explaining how ultrasonic cleaners work. The microscopic bubbles will form everywhere including deep inside small places that a brush cannot reach.

Wish I had one. 😪

 

[WFO-KZ]

I wished I had one too until I bought one and then I wished I had bought one decades ago. I think I spent about $150 CDN to get a nice big one. The tank is not big enough to fit an entire bank of 4 carbs (that was beyond my budget) but I can do the entire bank by angling them in and doing half at a time. The carbs were stripped down of course, just not separated.

It also does a really nice job cleaning up jewelry.

As long as you trust the shop you took your engine to, there is nothing wrong with one-stop shopping.
Can they weld the broken fin back on for you?

 

[Howitzer69]

Can they weld the broken fin back on for you?

Yes I think so.

 

[Howitzer69]

I asked the rebuild shop to give me a rough price quote on the work needed.

1. Crankshaft rebuild (I supplied the rebuild kit). They are going to send the crank out to be rebuilt. The shop they are sending it out too is back-logged and might not get to it for up to a month.
2. The shop will buy new rings and install them on my old piston.
3. The shop will clean up the cylinder (de-glaze/hone). Clean up the entire cylinder (nice and shiny, I was shown an example of a nice clean one they just did).
4. Clean up the head to make sure it's flat and true.
5. Weld on the broken cooling fin as well.

The amount I was quoted was approximately $200-300. They were not quite sure until they get the work done. You would think they would be more precise on a price quote, I guess they don't want to commit to a price until they see how much work they put into it. $300 may not be too bad considering the work being done.

I wanted to save a few bucks, the guy I dealt with seemed a bit frustrated by this, like I was just being chincey about it. Fair enough, I didn't want to look cheap about it but I do want to get as good of a deal as possible. I guess that's how it goes when dealing with a shop.

 

[WFO-KZ]

Did you ever get a quote from the other crank rebuilding places you contacted?