Technical 1.2 8V blown engine - replace or rebuild

[Davidbroooks]

My daughters 1.2 8V Punto (2000 X) broke down the other day. A quick check over revealed not much water in it and it looked like a classic overheat and blown head gasket. Turns out she hasn't checked the water for quite a while!

So I pulled the head off and uncovered a bit of a mess. Pistons 3 and 4 had bits missing off the crown, so it looked like a full or partial seizure. Got the sump off eventually (that gasket goo is pretty sticky) and got the pistons out. All but piston 1 has evidence of seizing, 3 and 4 being the worst.

Now I've done a quick tot up of replacement parts and gaskets (throw in a cambelt change while it's apart) and I won't have much change from £300, especially if the liners need a rebore and not just a quick hone.

I've seen a couple of 1.2 8V engines on ebay for around £300-£400 which is probably an easier option, but I'm confused about which one I should get.

From around 2001 it seems this engine has a cam sensor fitted which mine doesn't and talking to the dealers the two engines can't be swapped because the sensor is all wired into the loom.

Any ideas or advice?

 

[faster4_tec]

sounds like bin fodder,
I would be surprised if you could get that block rebored, new pistons, shell bearings (well you might aswell), and any damage to the head sorted, for £300 for parts only + boring job.

go to a local scrappy and get an engine from there, plenty of mk2's in them scrappies now, you can pick up a good working <40k mile engine for a mk2 8v for less than £200 no problem, probably even get a g'box in for that money too

problem with ebay sellers is they are often a generic photo, or they are scrappies selling stuff at massively inflated prices on hte t'internet

if it was me, I would go for replacement engine, cyl head and the lot, then just plug and play. I know you can't nessacerily do an entire change without a hoist, but theres maybe some damage to the block/crank from the seizure (sound slike a total seizure).

 

[Davidbroooks]

I absolutely agree and have decided a scrappy engine is the way to go, but my issue is with the cam sensor vs non-cam sensor engine. Can anyone shed any light on whether this subtle variation is a problem or not?

The two scrappys I've spoken to have engines that are a good price, apparently good miles and have been heard running, but both are the cam sensor variant. They have both said the engine won't work in a non-cam sensor car because of the loom and the ECU compatibility.

Can I just disconnect it or are they talking tosh?

 

[bandido41]

If you disconnect it i dont think it will start

 

[faster4_tec]

I wasn't aware there was two varients of the mk2a 8v fire engine


I think it still will have a crank TDC sensor, but maybe just obscured from view, or it could be on the cam pulley etc

 

[The Sultan]

right it's simple

put your cam pulley/crank pulley and new cam belt for your year of car onto one of these cam sensor engines then simply swap the rocker covers so there is no hole for the sensor evident

the only difference is the crank cam pulleys and cover and different cam belt and various cam belt covers also

then it will work on your engine harness and ecu without sensor

you might need your throttle body also as there may be wiring differenced up there too

but esencially there the same

the shape of the inlet manifold to head will be different i think but this will make little or no effect on the engine running on your older ecu

 

[Davidbroooks]

I'd sort of thought that would be possible and just needed a bit of confirmation. I think most of the srappys I've spoken to are thinking I was going to swap the entire unit complete with loom. All I really want is the block intact and swap over whatever I need to make it work.

I had a closer look at teh engine parts last night and the big end shell bearings are badly pitted - I think the bits of the piston crown have got in there.

Thanks for the help guys. I'll let you know how it goes.

 

[The Sultan]

you could stick it in and not change anything over and it will work on your harness

but from an aesthetic point of view you don't want a hole for a sensor that aint there and cam pulleys with noches in them excetra

if your going to change cam pulley over as the cam shaft is identical change crank and water pump aswell as i believe your cam belt will have a different pitch or number of teeth from the donor if you leave it with it's cambelt on you run the risk of someone in the future ordering bits to chassis number and finding they are wrong

 

[Davidbroooks]

I have no time during the day to scour scrappies, so I went to 247spares dot co.uk and within 10 minutes had a text with my first offer. Rang the guy, who explained that an engine with a cam sensor will go in a non cam semsor car, but not the other way around - just leave it disconnected.

Waited for a few more quotes, but ended up going with the first one. Ordered it at £352 inc vat and delivery and it turned up within a few days. It's a 2002 with about 50K miles. It looks clean and has plenty of compression, but I've got 30 days warranty. I might have got one cheaper if I'd done the rounds, but I think it was pretty good value since it was delivered to my door!

The old engine is out and the new one is waiting to go in, although the clutch release bearing seams to be a different size, so I've swapped them.

More news tomorrow when the engine's in a running (hopefully).

 

[The Sultan]

I have no time during the day to scour scrappies, so I went to 247spares dot co.uk and within 10 minutes had a text with my first offer. Rang the guy, who explained that an engine with a cam sensor will go in a non cam semsor car, but not the other way around - just leave it disconnected.

Waited for a few more quotes, but ended up going with the first one. Ordered it at £352 inc vat and delivery and it turned up within a few days. It's a 2002 with about 50K miles. It looks clean and has plenty of compression, but I've got 30 days warranty. I might have got one cheaper if I'd done the rounds, but I think it was pretty good value since it was delivered to my door!

The old engine is out and the new one is waiting to go in, although the clutch release bearing seams to be a different size, so I've swapped them.

More news tomorrow when the engine's in a running (hopefully).

there were 2 different designs of clutch release bearing use the bigger diameter one as the smaller ones give trouble

also use the clutch lining with the most material left on it

actually i don't know why you arnt using a new clutch wile it's all apart


and as for the guy on the phone

you can put a non sensor engine in a sensor engine car

you just need to swap the water pump cam cover cam pulley crank pulley and cam belt over simple then you have a hole for it and of course use the cars wiring not the one that comes with the engine

 

[Davidbroooks]

The clutch on the old engine was fine so I used that.

Anyway, the engine's in running and sounding pretty sweet now. Lining up the drive splines while guiding the engine in single handed was a mission, but the whole process was done in a day. The only problem I had was one of the injectors on the new engine wasn't behaving so I just swapped it for the old one.

Thanks for the info guys. If anyone needs any of the good parts off the old engine let me know.

• Cylinder head complete
• Water pump
• Crank
• Flywheel
• One good piston and rod