Cant get pistons out

[TIB3300]

Hello
I have an engine with new rings fitted to the pistons and want to take them out , but the bore has a lip and the rings wont go past it.

This is a new problem to me, done a bit of reading up and seems I may need a ridge reamer. Is there another way to get them past?
and If I was to buy a ridge reamer what's best but not silly money as will probably only use it this once
thanks

[Pete]

Well, the previous owner managed to bash them in past the ridge to get them in....

If the ridge is that bad, then I bet the motor needs a re-bore anyway....

Check the Bores along the thrust line with an expanding Micrometer to see what the wear on the bore is like.

Bore to piston skirt clearance should be around 0.0035 - 0.004"". I bet your Ridge is more than that if you can't get the pistons out...

Plan "C" time, I fear.....

[TIB3300]

Well, the previous owner managed to bash them in past the ridge to get them in....

If the ridge is that bad, then I bet the motor needs a re-bore anyway....

Check the Bores along the thrust line with an expanding Micrometer to see what the wear on the bore is like.

Bore to piston skirt clearance should be around 0.0035 - 0.004"". I bet your Ridge is more than that if you can't get the pistons out...

Plan "C" time, I fear.....

Nope still, plan B.1 but with rebore and new pistons maybe???

[Pete]

Quite possibly, and a re-balance.

Worth looking at a stroker rotating assembly as once you have weighed up the parts and machining cost you are not a million miles away from a 440 source unit - and it is all new and balanced with rings and bearings.

You really need to check everything that the previous owner has done / had done, as they clearly have cut corners on the Pistons / Rings and Bores.

That timing set does not look great either - hard to see from the pictures but I would only ever fit a double roller if I was not using Gear / Belt drive....

[TIB3300]

Well, the previous owner managed to bash them in past the ridge to get them in....

If the ridge is that bad, then I bet the motor needs a re-bore anyway....

Check the Bores along the thrust line with an expanding Micrometer to see what the wear on the bore is like.

Bore to piston skirt clearance should be around 0.0035 - 0.004"". I bet your Ridge is more than that if you can't get the pistons out...

Plan "C" time, I fear.....

After speaking to a chap at Sheffield engine sevices. Was to to bash them!! well what do you know, came out.
Bit of lube and a bit more enthusiasm I was worried of more bad news by breaking something.

[Pete]

I was worried of more bad news by breaking something.

Remember: "Measure, Measure, Measure".

You will probably find that the bore is excessively worn and that the Pistons and Rings you have just removed need replacement in any case.

I would imagine a re-bore is on the cards if the Ridge is that big....

[Dave999]

This might work
if you have an old set of feelers...
or a cheap Chinese set
oil them
if its worn they might well go in bit of wiggling

piston down an inch
ram 3 feelers between it and the bore 120* apart. they will get pushed out but you just need the first ring past the ridge before you re apply wtice more

push piston up

it might save the rings

but if it needs a rebore anyway hone or abrasive paper over the ridge to smooth the way

last resort welly them out


Dave

[TIB3300]

I was worried of more bad news by breaking something.

Remember: "Measure, Measure, Measure".

You will probably find that the bore is excessively worn and that the Pistons and Rings you have just removed need replacement in any case.

I would imagine a re-bore is on the cards if the Ridge is that big....

Looking at it with the pistons out, its not that big a ridge. It was just with it having new rings in it,, it was tighter then old rings.

But yes will "Measure, Measure, Measure".

[TIB3300]

Quite possibly, and a re-balance.

Worth looking at a stroker rotating assembly as once you have weighed up the parts and machining cost you are not a million miles away from a 440 source unit - and it is all new and balanced with rings and bearings.

You really need to check everything that the previous owner has done / had done, as they clearly have cut corners on the Pistons / Rings and Bores.

That timing set does not look great either - hard to see from the pictures but I would only ever fit a double roller if I was not using Gear / Belt drive....

Have you seen this make befor? any good ?

[Pete]

Personally I would not use one of those = I think they are called a "Hyvo" style and are designed to run more quietly - they are of cheap manufacture and I would only use a Double Roller Timing chain or a Belt or Gears.

It is amazing how quickly the set ups wear in a v8 with no tensioner, but they seem to keep working...

[TIB3300]

Personally I would not use one of those = I think they are called a "Hyvo" style and are designed to run more quietly - they are of cheap manufacture and I would only use a Double Roller Timing chain or a Belt or Gears.

It is amazing how quickly the set ups wear in a v8 with no tensioner, but they seem to keep working...

Thanks


Where would one get a Double Roller chain ?

What name to look out for?

[Dave999]

I used Romac aussie gears with German IWIS chain.
also sold in the US for 318s etc under the ROLLMASTER brand

the one you took out looks like an aftermarket copy of the standard type or maybe the standard one. nothing wrong with them but better exists for little extra outlay and much less stretch in use

Dave