Getting pistons back into cylinders!

**Max Preload** · 21st November 2010, 16:41

Lubricate the bore and gudgeons lightly with ATF (automatic transmission fluid). It burns off quickly on start up. Position the crank so all the conrods are at the same height.

You start on the middle two cylinders. Put all the pistons, with the inward facing gudgeon pin circlips already in place, into the bottom of the the sleeves just high enough that the oil ring is captive in the bores for the middle two piston, and well up into the bore for the outer two pistons, then match up the two middle conrods with the pistons and put the gudgeon pins and outward facing circlips in. Then you tap the outer two pistons down to allow those gudgeon pins and circlips to go in easily.

**Max Preload** · 21st November 2010, 16:53

Originally Posted by cbfb

I have heard about a ring compressor, but I can't figure out how it would work if I'm trying to slide the block over the assembled pistons?

I doubt very much that the dimensional constraints will allow you to.

Originally Posted by cbfb

No the conrods stay in place and the pistons go on the little ends, then the block goes on top. That's what it says in the manual anyway...

That will be very difficult. Put the pistons in the liners first.

**cbfb** · 21st November 2010, 17:03

Originally Posted by Max Preload

Lubricate the bore and gudgeons lightly with ATF (automatic transmission fluid). It burns off quickly on start up. Position the crank so all the conrods are at the same height.

You start on the middle two cylinders. Put all the pistons, with the inward facing gudgeon pin circlips already in place, into the bottom of the the sleeves just high enough that the oil ring is captive in the bores for the middle two piston, and well up into the bore for the outer two pistons, then match up the two middle conrods with the pistons and put the gudgeon pins and outward facing circlips in. Then you tap the outer two pistons down to allow those gudgeon pins and circlips to go in easily.

This sounds much easier, couldn't see the wood for the trees. Will have to get a base gasket sent out (hopefully not from Japan) then will get cracking.

Many thanks

**Paul in NZ** · 21st November 2010, 17:11

If you look at the bottom of the block where the sleeves stick out, is there a pretty decent champfer? ie is there a taper into the cylinder?

If there is a good sized one it is just possible to do this without a hose clamp or ring compressor provided you have help and work carefully. If you are unsure a hose clamp will help.

**Katman** · 21st November 2010, 17:15

There's a reason mechanics aren't made overnight.

**Paul in NZ** · 21st November 2010, 17:23

Originally Posted by Katman

There's a reason mechanics aren't made overnight.

Is it because the manuals are still in japanese?

**cbfb** · 21st November 2010, 17:34

Originally Posted by Paul in NZ

If you look at the bottom of the block where the sleeves stick out, is there a pretty decent champfer? ie is there a taper into the cylinder?

If there is a good sized one it is just possible to do this without a hose clamp or ring compressor provided you have help and work carefully. If you are unsure a hose clamp will help.

Yep there is a bit of a chamfer, but the rings don't quite fit in without some effort. However if I use Max Preload's suggestion and fit the pistons one by one beforehand, it should be OK (I have tried this and because of the chamfer like you pointed out, it slides in nicely). Just wouldn't be able to get all four in at once very easily.

Originally Posted by Katman

There's a reason mechanics aren't made overnight.

+10. I enjoy learning though, especially when something really tricky comes right.

Originally Posted by Paul in NZ

Is it because the manuals are still in japanese?

LOL well at least it keeps people coming back to KB!

**cbfb** · 25th November 2010, 20:37

Just a quick update, I had a crack at this tonight. A wee bit tricky but not nearly as bad as I thought it would be.

Tried putting the pistons in the block and installing like that, no go, far too little room to work. So installed the pistons on the conrods and lowered the block down, 2 pistons at a time (inside first) with a bit of help from fingernails and a flat, thin bit of metal. Even did it all on my own without an adult helping

THANK YOU to everyone who replied, appreciate the help.

**Crasherfromwayback** · 25th November 2010, 21:16

But I think you'll be doing this all over again.

Next time...why don't you ask a nice mechanic if you can watch him/her do it correctly. It's great that you want to be able to do such things...but you were way over your head.

**cbfb** · 26th November 2010, 07:34

Originally Posted by Crasherfromwayback

But I think you'll be doing this all over again.

Can you elaborate before I bolt the head back down? If there's something you think I've missed I would appreciate the advice. I have followed the service manual to the letter and given the crank a few turns since putting the pistons back, all seems ok. Many thanks.

**Crasherfromwayback** · 26th November 2010, 11:57

Originally Posted by cbfb

Can you elaborate before I bolt the head back down? If there's something you think I've missed I would appreciate the advice. I have followed the service manual to the letter and given the crank a few turns since putting the pistons back, all seems ok. Many thanks.

I simply think you've bitten off a tad more than you can right now chew. Good on you for having a go mate, and I hope it all works out ok!

**cbfb** · 26th November 2010, 12:05

Originally Posted by Crasherfromwayback

I simply think you've bitten off a tad more than you can right now chew. Good on you for having a go mate, and I hope it all works out ok!

Ah OK, thanks, I've done everything in the manual, checked the piston, bore, pin dimensions, replaced the circlips etc etc as it instructed. Hope I've done everything right. This was the only bit I got stuck on cause the manual said to just whack the head back on... but that's what KB is for.

Anyway cheers will hopefully get it finished on Sunday and fire it up.

**Crasherfromwayback** · 26th November 2010, 12:18

Originally Posted by cbfb

Ah OK, thanks, I've done everything in the manual, checked the piston, bore, pin dimensions, replaced the circlips etc etc as it instructed. Hope I've done everything right. This was the only bit I got stuck on cause the manual said to just whack the head back on... but that's what KB is for.

Anyway cheers will hopefully get it finished on Sunday and fire it up.

Good stuff. Make sure you turn the engine over by hand before you try and fire it up, just incase you have the valve timing wrong. Bending those lil valves is expensive!

Pete

**cbfb** · 26th November 2010, 12:22

Originally Posted by Crasherfromwayback

Good stuff. Make sure you turn the engine over by hand before you try and fire it up, just incase you have the valve timing wrong. Bending those lil valves is expensive!

Pete

Will do, thanks

ps have also checked the head isn't warped, not done the valves as i don't have the tools/knowledge.