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Ok it's beginning to look a lot like a project!

I wouldn't be cutting anything off of moving parts as it will upset the balance don't forget race engines this is one of the things they do for reliability make sure all moving parts are the same weight with a 3 bearing crankshaft this is especially important
 
mr-reno-139 said:
I wouldn't be cutting anything off of moving parts as it will upset the balance don't forget race engines this is one of the things they do for reliability make sure all moving parts are the same weight with a 3 bearing crankshaft this is especially important
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I did wonder, it really is a tiny amount, but I'll just have to fit em from the bottom. The engine is so mucky I think it's best to strip it down & take crankshaft out, in my Haynes it says take off bearing caps & lift it out, but I've tried this & the chain stops it from being lifted out..I'm missing something here yes? !
 
mojobaby said:
Yes, I remember the cleaning, it seemed to carry on for days and days:)

Is it the side of the engine block that is preventing the piston from moving? I seem to remember that I had a similar problem, which is strange because I was using all the same original parts.
The bottom edge of the connecting rod wasn't actually touching anything, but I think it was too close for my liking, so I also shaved a bit off, perhaps about 2mm, from the bottom edge corner of the connecting rod.

It was such a long time ago that I did it, that I can't remember exactly why or what I cut off, but I think it was the connecting rod
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the pistons in the 2nd donor engine go into the sleeves then just a turn upright of the piston & it goes down, mine will not straighten up, there is a tiny bit too much metal on the connecting rod that stops it from being able to go upright, frustrating!
 
Before you take the chain off, there is a small dimple mark on both sprockets. Get some white paint and make a mark on the chain where it meets the sprocket marks. That way you'll be able to set your timing again without any fuss.

Take as many photos of everything, it will help you later when you put the car back together.

I understand now when you said that the pistons couldn't go into the sleeve. The way you explained it sounded like the pistons themselves were too big, but now I understand what you mean but sadly I have no idea how to solve it.

Putting the pistons in from the bottom sounds like a bad idea, firstly because you'll probably have to take the rings off first and then put them in from the other side after the pistons has been inserted. And secondly there is a chance of disturbing the liner seals. But maybe there is no other way.

Hopefully someone will have some better advice for you
 
Do you think that removing (and resealing) liners would be beyond your capabilities? That way you will be able to insert pistons from the bottom of the liner, then fit liners/pistons/rods in the block as an assembly. Otherwise you have to take off timing chain, which is not too easy a task as both timing gears are press-fitted on their shafts.
 
angel said:
Do you think that removing (and resealing) liners would be beyond your capabilities? That way you will be able to insert pistons from the bottom of the liner, then fit liners/pistons/rods in the block as an assembly. Otherwise you have to take off timing chain, which is not too easy a task as both timing gears are press-fitted on their shafts.
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my pistons are out already, timing chain coming off this pm...it isn't the difficulty of the task it is knowing how to do it, most jobs are ok after the 1st time doing them I find.
 
mojobaby said:
Before you take the chain off, there is a small dimple mark on both sprockets. Get some white paint and make a mark on the chain where it meets the sprocket marks. That way you'll be able to set your timing again without any fuss.

Take as many photos of everything, it will help you later when you put the car back together.

I understand now when you said that the pistons couldn't go into the sleeve. The way you explained it sounded like the pistons themselves were too big, but now I understand what you mean but sadly I have no idea how to solve it.

Putting the pistons in from the bottom sounds like a bad idea, firstly because you'll probably have to take the rings off first and then put them in from the other side after the pistons has been inserted. And secondly there is a chance of disturbing the liner seals. But maybe there is no other way.

Hopefully someone will have some better advice for you
Click to expand...
great advice as usual Dave, thank you
 
I'm thinking there must be a lifespan on these skinny bits of metal & 43 years seems to be beyond it.
I've read all of Jurjenz's & Mojobaby's rebuilds now chapeau to both of you.
 
Wow! Wonder what could have caused that?

overheating? No lubrication? Just as well you're doing a thorough cleaning of your engine, just to make sure all the little oil passages are clear.

Well done to you and thanks for the comment:)
 
that's mine, which I thought was bad enough then I discovered the other one!
This deterioration is caused by contaminated oil I'm guessing?
 
it is only the one like this, same one on both engines nearest the timing chain
 
Not good but provided that it is only the white metal bearing not disastrous. I have seen worse but not on an R4. Is there any damage to the crank and will it clean up with a regrind and plus size shell bearings.
 
Wow, never seen crankshaft bearings with that kind of tear and wear, and on 2 engines simultaniously.
About the lifespan, it has nothing to do with age and on my first R4 after 480,000 km (300,000miles) everything was stil smooth.
I would suggest to do a complete engine rebuild, with a (refurbished) balanced crankshaft, new pistons and liners etc. etc.

And change the topic header because this is definitely a complete project
 
this is the first time I've removed these parts, so basically this is pretty dire & this is actually the bearing I am looking at? so this would explain cutting out at low revs, not being able to set timing properly, uneven idling, feeling of catching when trying to start? & what would cause this kind of wear, just filthy oil & no changes, overtight belts?
 
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