So this Saturday I finally got round to stealing my dads garage and fitting my ported and polished cylinder head with high lift cam that I brought from Brin a month or so ago.

Didn't have too many problems as I've spent a while planning my steps to stop my self going round in circles.

One of the original plans was to paint the engine black and red but after looking into the time to remove engine I settled on painting the cylinder head and rocker cover, however when I had my engine cleaned last Monday it would appear they "missed" several bits including the rocker cover so I may go for a polished rocker cover from MrFixIt and the paint the exhaust manifold black to match the head.

Anyway, the first problem was the HT Lead on the spark plug for cylinder No. 1 broke and the metal contact remained on the spark plug. The second was access to the engine mount bolts on the side of the cylinder head, to get around this I left the last part of the mount on the head and disassembled later.

Before separation I rotated the bottom crank until the timing marks on both cranks lined up, I quickly realised what is meant by being 360 degrees out as the bottom crank turns twice for every rotation of the cam shaft.

I also inspected the timing on the new head and cam as the crank was changed to be suitable for use with the crank sensor, measuring and comparing the location of the lobes on the heads it was clear the head had been set up timed ready for bolting on.

My dad expected the cylinder head and block separation to be difficult due to age of car, if it wasn't for the fact that the bottom end is from an Punto 60 SPI (unsure when replaced) he probably would of been correct but it came apart surprising easily. I don't think a torque wrench was used when the engine was replaced as I had no difficulty in removing any bolts.

Once the head was off I blocked off the water, oil and bolt holes. Also i greased each cylinder to prevent anything falling between the piston and cylinder. I then used some degreaser and a Stanley blade to remove any left over gasket and residue, judging from the condition of the gasket and the colouring on the matting surfaces it would seem the gasket was starting to fail. I then took a sponge and degreaser to the piston heads removing as much grime as possible, if any ones considering a gasket or head change get some emery cloth, it would of been a lot easier to clean up and probably would of done a lot better.

Reassembly went well, 6 of the studs for the exhaust manifold came out with the nuts during removal but the nuts came off easily one the studs were in a vice. The only crap bit was getting the phonic wheel back on the bottom crank, the bugger just wanted to spin the crank. Help with this came from the least likely of people, my sister. The broken HT Lead I repaired (bodged) by pushing back in and checking it made contact with the cable with the help of a torch.

Once everything was back in I started it up. it took a few turns if the starter and it went, and if I'm honest it sounded absolutely bloody awful, it would run for a short while and then cut out, if I gave it gas it would cut out. Unplugged the damaged HT Lead and it wouldn't even start. It sounded as tho it was only firing on 2 cylinders, my first thought was that when cleaning the piston heads the crank went round 1 too many times. By now it was 10:30 and the mrs was screwing so I got a lift home to sleep on it and browse the net.

So Sunday I got some HT Leads from halfords as I needed a new set anyway. On the evening I got picked up and went for round 2.

I took my old laptop and OBDII lead, although only free versions of software, I got 2 error codes, one being a fault in coil pack B primary/secondary circuit. The other was lamba sensor bank 1.

The first thing I did was check all cables and connections, i then changed the HT Leads and it ran a bit better but still terrible. I had replaced the bottom crank sensor with a 2nd hand one I purchased as where the wire joins the cable it looked as though it had be scrapped along the floor and you could see the inner wires. I put this one back on and it ran about the same.

Next I went for the timing and soon discover the top crank was out anti-clockwise by about 5 teeth!!!!! I realigned and put back together, however I found I needed to rotate the top crank half a tooth to get the belt on with the tension remaining on the belt at the front of the engine.

This time I started it up it ran and sounded a lot better, still only 90% but so much better, no cutting out on idle or when pressing the accelerator. The only way I can describe it is that it sounds like an old motor bike, certainly a head turner. After letting it warm up I took it round the block (steadily). At idle it sounds bad, accelerating not so bad, driving at a steady speed you can hardly hear it. I found the temp gauge shot up to just over half then rapidly dropped to 1/4, I assume this was due to the thermostat opening allowing water to fill the cylinder head and into the heater matrix.

There was a bit of smoke but I believe this was due the cylinder head paint and the small but of oil I spilt on the block/exhaust.

Although it runs it is slightly bad and still needs TLC. A further search of the net suggests a head skimmed by the max of 2.5mm can throw the timing off on top crank by between 6 and 12 degrees depending on number of teeth etc. Various debates but no real answers.

I believe the timing may still be out by a tooth in either direction.

Today I checked the water and oil, water needed topping up and bleeding again. Also I noticed oil all along the rocker cover gasket and coming from where the coil pack holder meets the head. I've purchased some sealant as I intend to seal the coil pack holder and all along the top of the head as this seams to be a common issue with these engines.

Essentially I need some advice. Do I "fine tune the timing" or am I looking in the wrong place?

Cheers

Sorry for the lack of links and pictures, currently on my phone so ill have to post later

Hard to say. Bottom end is from an SPI Punto? What did you do with the knock sensor?

Otherwise, the obvious way to set the timing is TDC on cylinder #1 (nearest timing belt). Both valves on that cylinder will be closed (cam lobes pointing towards the sky).

Can't remember what cam that car was using.

You may need adjustable cam pulley and a remap if MPI.

FCS, for the coil pack leak, get a new O ring. For the rocker cover, use a new gasket, and sealant, but clean the mating srfaces well with acetone, keytone, panel wipe, cellulose thinner, etc.

Never, ever, use abrasives on piston crowns.

ok so as promised here are some pictures and links,

here is the head and cam i brought off Brin

https://www.fiatforum.com/west-york...ly-reconditioned-port-polished-stage-3-a.html

you can see in the pictures the lobes for timing dont point towards the sky, how ever the timing marks match up and the lobes on the on the cam and head that were removed were in the same place with timing marks matched up, is this wrong?

pictures:

Engine stripped ready for head removal




Cylinder head removed




Matting surface on removed cylinder head




Piston heads cleaned






Damaged piston head on No. 1 piston




And finaly the mysterious placement of the knock sensor on my SPI bottom end



after several attempts i managed to get a non blury picture, it would apear the used a longer bolt on the mount bracket to attach it.


Last night one the guys in work asked if had put a tractor engine in

although i belive the timing could be out by a tooth in either direction is there a chance i could be 360 degrees out on the timing? would it even run? my next step is to get a good video with decent audio as it may well be a knocking noise rather than timing issue.

360 degrees out would be perfect!

What ECU does it have? I'm thinking that the P75 never had a knock sensor (earliest MPI engine).

There are a few "obvious" non piston related causes of top end knocking:

Loose steel baffle in rocker cover
Valve clearances
Worn cam bearings
Cam end float (pull and push the cam pulley)

If it's noisy, chances are that the issue is mechanical.

fingers99 said:

360 degrees out would be perfect!

What ECU does it have? I'm thinking that the P75 never had a knock sensor (earliest MPI engine).

There are a few "obvious" non piston related causes of top end knocking:

Loose steel baffle in rocker cover
Valve clearances
Worn cam bearings
Cam end float (pull and push the cam pulley)

If it's noisy, chances are that the issue is mechanical.

Click to expand...

I'm not sure what ecu it has, I know just because I have one key that fits all the locks doesn't mean it hasn't been changed, how would I find out? I think it's the original, my car is a 51 plate.

I'm fairly certain that the steel baffle isn't loose and the valve shins, cam berrings and end float should of been done when the head was reconditioned and the cam was fitted. Before fitting the head I did have a look over it and couldn't find any play in the cam berrings.

When I check the timing I'll have to get the feeler guage out and re check all the clearances.

Thanks

I'd check. As I say, mechanical noises are usually, er mechanical.

For the ECU, it'll have a label on it somewhere.

I did check the clearances and the bearings on it mate they were all perfect...also the fact that I actually ran this head on my turbo conversion without any problems mate...is it coming from the engine or near the exhaust? You sure the exhaust is not leaking gases as that can sound like an old motorbike engine mate from either the head or even lambda sensor holes mate

I would re check the timing set the timing perfect then put the tensioner on that's how I do them mate and don't usually move...did Oi touch cylinder walls when cleaning pistons as can cause the rings not to seal if scored mate...how did the damage to the piston happen and the knock sensor should not be there mate

Thanks fingers and brin

Well I've been swaying from mechanical to exhaust as I've noticed while idle you can barely hear it, whilst driving along if I take my foot off the accelerator with the gearbox engaged and let the car roll under its momentum it practically disappears, also the flex pipe looks battered. Surely if it was mechanical the noise would stay?

I greased the cylinders before cleaning to stop crap getting in.

The damage to the piston was already there when I removed the head.

I know the knock sensor shouldn't be there but at some point the bottom end had been replaced with one from a spi engine that doesn't have the knock sensor lug, so who ever did it put it there.

The cars previous owner lived in bath, the front licence plate has a Coventry post code so I have no idea when it could of been done.

I have 4 hours between a meeting at work and my actual shift so I'm going to recheck timing, exhaust system. I'll rotate the crank to see if oil spouts from the oil rail to make sure oil pick up works, I'm fairly sure the gasket is on the right way round as one corner had 3 holes and these matched the bottom right corner of the block matting surface. But I'm concerned that as its a spi bottom end the gasket could be wrong?

Thanks again

You'll need to get someone to crank it, rather than just turn it over with a spanner. Briefly, or you may have oil everwhere.

fingers99 said:

You'll need to get someone to crank it, rather than just turn it over with a spanner. Briefly, or you may have oil everwhere.

Click to expand...

bottom end should be same although you will not have any oil squirters for the cylinders, if headgasket is wrong way oil will not come up to the cam, people on this forum have done it before as you block the oil gallery that sends oil up onto the car...be careful will wear the cam if keep running like that mate

Gasket is the same (MPI for SPI). But it is possible to put them on the wrong way round and block up the oil hole that feeds the cams.

Ok so time for an update, at work Friday night it was pointed out that emissions were coming from the front, put a glove on and put my hand on the end of the exhaust, engine noise changed slightly but it was apparent there was no pressure at the back.

In the morning I fixed the oil leak on the end of the cam where coil pack sits, I removed rocker and cranked the engine, got some oil out of the rail so the gaskets on the right way round. Next I checked the timing and it was practically perfect, it was only a fraction out.

Whilst I had the car jacked up I climbed under to check the exhaust system with a torch. I couldn't see any thing obvious apart from the damage on the bottom of the flex joint. I found the casing obscures view of the inner flex joint so couldn't really see. I got a friend to start it out. I could feel gasses escaping from this area and could also hear a slight hiss aswell.

Fingers i had a look on the ECU and i believe this is the info?

IAW 59F.M3/WH303/1812-OMZ

No probs. I just wondered if somehow it had been fitted with an SPI ECU.

Pull off the accursed manicat and take a peek. They do split, and the heatsheilds also come loose. They be bad, bad, things.

fingers99 said:

No probs. I just wondered if somehow it had been fitted with an SPI ECU.

Pull off the accursed manicat and take a peek. They do split, and the heatsheilds also come loose. They be bad, bad, things.

Click to expand...

yeah i noticed its one piece not 2 seperates, dont imagine they being cheap, the heat sheild was missing when i got the car.

the cars booked for a free exhaust check tomorrow at kwik fit round the corner so ill find out soon enough

A way forward -- manicats almost certainly impede performance, too, is a Mk1 manifold (or a performance one) and a Mk1 cat (Rover K V6 ones are a similar size and very cheap) with the second lambda mounted after the cat (assuming you have 2 lambdas).

But see what Kwik Fit turn up.

So today (a week late) I went to kwikfit for the free exhaust check. Wasn't there long but it turns out to be the bolts on the exhaust manifold. 3 were loose and ones come off. Felt like a total numpty.

They tightened the 3 up and said they'd have to wait an hour for it to cool to replace the missing one, that tho I can do my self.

It sounds a lot better and that last bolt should help.

To be honest I don't know how I missed that.

i remember when i turbo'ed my punto and i had to knock the timing back abit to run higher boost but i went too far.... on the upside it sounded exactly like a punto with a impreza wrx engine dropped in!