I'm wandering if someone has done this to salvage a cracked block?

Are these a dry liner engine (outside of sleeve only touches metal not coolant), maybe it had bad rebore and this was the only way to make it usable?

A practice piece for a machine shop apprentice?

Yes.. that's my thought.

If there isn't a "750cc race series" that this engine was modified for (and there are no signs of any other porting or tuning work in the engine) then that suggests the new liners were squeezed in there to solve a problem with the original liners (some parts of which appear to still be in there).

It could be that the engine seized up or had a valve failure (etc.) that wrecked one or more liners... or as you say, there could have been a bad rebore etc.... except that I have no idea how fitting 4 new liners and pistons would be cheaper than just replacing one or two damaged liners and pistons with original equipment. It's a weird one.

I also tried to find a 57.8mm piston. Fiuders will be pleased to know that the only 57.8mm pistons out there are made for single-cylinder 150cc Chinese scooters. Ahhhh Ahhhh Ahhhh It's none of it good... Hopefully in a few years time, Fiuders will at the least have an amusing story to tell..


Ralf S.

Yeah i dont know if i want to put this in my car.
The original engine has seen about 180000 Kilometers.

The problem with the original one is the seicento ticking noise from the lifters and a possible head gasket leak, which both would be fixed by just swapping the refreshened head from this engine, so i think ill ditch the bottom, as it makes for a really weird engine.
Like having the ecu spray as much gas as it would spray for a bigger engine, a stupid gap inside the head gasket and possibly the emissions going totally haywire.
Also the loss of power would propably be quite substantial.

Again, the pistons wont come out from the back because the casting is blocking them from coming out, trust me, ive tried in every possible way.
Not that im even really interested anymore on removing them.
I looked into re-boring and sleeving this, but makes no sense for the cost.

In that case the pistons could ofcourse be taken out in pieces, but not gonna do that.

Even the pistons (if could be found from anywhere to begin with) would propably cost more than i would be willing to pay.

Maybe if the engine which is on the car would like some underside renovation at some point, would just go and do it a bit quik and dirty while the engine is still attached to the car.

For now i propably just go with the head.

btw, if anyone has a spare tappet plate (the small coin kinda thing behind a tappet) i could be interested, as i think i lost one .

Could just get one made on a lathe tho wouldnt even cost much.

From now on this thread will propably be mostly about the head, and maybe gonna go and see what the gas spraying thingie with a round black hat has eaten.

Thank you all for the replies! Been a pleasure

Ralf S. said:

Yes.. that's my thought.

If there isn't a "750cc race series" that this engine was modified for (and there are no signs of any other porting or tuning work in the engine) then that suggests the new liners were squeezed in there to solve a problem with the original liners (some parts of which appear to still be in there).

It could be that the engine seized up or had a valve failure (etc.) that wrecked one or more liners... or as you say, there could have been a bad rebore etc.... except that I have no idea how fitting 4 new liners and pistons would be cheaper than just replacing one or two damaged liners and pistons with original equipment. It's a weird one.

I also tried to find a 57.8mm piston. Fiuders will be pleased to know that the only 57.8mm pistons out there are made for single-cylinder 150cc Chinese scooters. Ahhhh Ahhhh Ahhhh It's none of it good... Hopefully in a few years time, Fiuders will at the least have an amusing story to tell..


Ralf S.

Click to expand...

Maybe i could now show this thing some angle grinding ledgehammering love to try and remove the sleeves to figure out if there is something going on in the block, will remain to be seen if i get motivated on doing that

A chinese scooter version of seicento would be kinda rad tho

Interestingly, I think.

The 750 motor club in the UK has allowed Fiat engines since 2003, but its the 1108cc Fire engine that they use.

D

Could you temporarily refit the crank and check the stroke on the engine?

If the bore has been messed with you never know if the crank is standard.

Wiki shows a USA only 817cc engine but offers no info for bore/stroke size.

Stroke seems standard

Fiuders said:

Stroke seems standard

Click to expand...

Yes... to change the stroke you would need shortened con-rods and a whole lot of machining off the block.. then modifications to the push-rods etc. - you really wouldn't bother.

In any case, look how thick those liners are. Someone really wanted to put new liners in there. I presume they chose the 57.8mm pistons because they could be the only pistons they found that fit onto the stock (?) Fiat con-rods.

I don't think reducing the capacity was the main intention... I only don't understand how all this was cheaper/easier than just fixing any damage using OE spec' parts.


Ralf S.

Ralf S. said:

I only don't understand how all this was cheaper/easier than just fixing any damage using OE spec' parts.

Click to expand...

Yes very odd.
An awful lot of work to make the engine produce less power, especially when you consider I nearly purchased a spare 899 engine for £50 a few years ago...

Maybe someone had had bad luck with blocks cracking, and built this one for extreme longevity

Did removing the wrist pin and pushing the piston out the top work?

That might work, but not gonna bother as im not gonna use this anyway.

Ralf S. said:

Can the engine ever have been sleeved down? Is there some engine size/formula that makes the car cheaper to insure/for young drivers etc. in Finland? Or some 700cc race formula? The shells are quite worn for a road engine...

Meanwhile, there is no 4-cylinder "700cc" standard Fiat engine. The twin cylinder 700cc engine out of the 126 and Polish market Cinq's wouldn't have a 57.8mm bore... and your engine comes up as a standard 899cc on ePer.


Ralf S.

Click to expand...

Thick sleeving and Fiat Panda 750 pistons might be the answer.