Hello,

I have just asked the garage to do a compression test on my 1996 Fiat Punto 55s 1108 as I wanted to check whether there were undetected problems with the head gasket etc before shelling out on other repairs needed (replacing water pump along with replacing timing belt given this has to be removed to get to the water pump anyway and car has done around 87 000 miles).

I was told that for cylinders 1, 3 and 4 their psi is 100 but cylinder 2's is 60. However I'm having trouble finding out what they should be - the Haynes manual tells you how to do a compression test but not what the results should be! Similarly a quick Google isn't bringing anything useful up so I wondered if someone here may know please? He did also say that spark plug 2 needs to be replaced.

The mechanic said that 100 is ok but 60 is a bit low but in his opinion doesn't need replacing now. However I only got the car for £395 a month ago and the repairs will cost around £350 plus the costs for initial quote, so don't want to pay this only for further work needing to be done soon. I wondered if anyone can tell me what is an acceptable psi for this car and what the difference in the results for the cylinders shows?

Would be really grateful if anyone can advise.

Cheers.

100 psi is low, 60 psi is extremely low. I've seen better than 100psi on engines I considered virtually scrap, but it does depend to some extent on how the test is done.

You really need a dry and wet compression test which will help determine if you have a valve or a cylinder bore problem. I'd have expected the garage to do this.

You don't say why you suspected a head gasket problem in the first place.

This is an absurdly easy car to DIY. That's the obvious way to save a lot of money.

what they should be is the same.. 1 being lower than the others shows there is a problem..

How handy are you with spanners? Its not too hard a job to do yourself if you have a haynes to refer to.. Actual cost of parts isn't alot, the cost is all in labour.

I can't advise on the pressure test results (not my thing) but when doing a head gasket you are virtually replacing the cam belt anyway and the water pump is about 2 mins work in these circumstances, so if you do go ahead with the head gasket work then put the pressure on the garage to keep the labour prices to the absolute minimum

Hi, thank you all very much. This is my first car and have never done any repairs so have to say completely inexperienced with doing it myself and don't have anywhere other than street to do any work on the car - so I'm aware even smaller jobs may add up due to labour costs.

The reason I wondered about the head gasket was that the car started overheating on a long journey, so I stopped to let it cool down and topped up the coolant, then it happened again and there weren't any stopping places so had to drive on for about 2-3 miles and it seemed to be losing power (couldn't go any faster than around 55 mph, would have gone slower but had a big truck tailgating me). When I was able to pull over there was white steam coming out of a hole and some liquid. Called my breakdown cover, someone came and bled the radiator and said it was 'fixed' and they'd suspected air trapped in the radiator. We drove on 20 miles to destination with no obvious problems but on the way back it happened again (we were towed back). There is now an obvious coolant leak (when you top it up it immediately comes out elsewhere, which the mechanic said is the water pump) and the heater in the car doesn't blow hot air (which the mechanic said is due to a low level of coolant in system due to the water pump leak). When I looked online about the steam etc it seemed similar to head gasket problems at first glance, but I've not noticed smoke from exhaust although didn't look for this at the time. I believe this type of car is notorious for hg problems though so thought may be best to check to get an idea of total repair costs. As the compression isn't low between two cylinders on the hg, I believe this suggests this isn't a problem with the hg itself but could be a sign of problem with valves/piston/other?

So far the garage advised 3 hours of labour as apparently it takes time to get to the water pump to replace it?

Any other tips much appreciated, thank you.

i would want a minimum 150 a pot on a warm engine throttle open
ideally i would be looking for 175 a pot
10% discrepancy between pots acceptable
otherwise i would be looking for a newer engine or considering some new rings

well there is defo a problem with the cooling system, the question is has it got too hot and thus high pressures caused a leak because the HG has gone..

OR..

does the car overheat cause there is a problem with the cooling system itself.


Given your compression test results i'd be inclined to think that your HG has gone and as a result car has overheated causing damage to the cooling system. In which case the HG will need changing, head will need skimming while off - and while the engine is in pieces its best to change belts, tensioners, water pump etc
It is often cheaper to source another engine and just drop it in but unless you seen the engine running then its an unknown quantity and you may have all the same problems again, or others, or both.

There is no point fixing the water pump (if that is really what let go) if the HG has gone, it will just overheat again and break again - especially if you get in traffic!!

I doubt it's the HG, but can't see much point in throwing money at that engine. You can buy a decent one for less than £150. Same engine as Cinquecento or, you can probably find the bottom end from a Seicento and use that (likely to have a better choice of lower mileage engines).

As ever, the clue to saving money is to get your hands dirty.

why doubt HG though? surely those results shout out there is a problem, one cylinder nearly half the others??

Because it's only one cylinder. They'll almost invariably go over the shortest distance, which is between 2.

I suspect that the rings (at least) are shot on all 4, with possibility of valve issues on the lowest one.

fair do's i guess that makes sense.. the last headgasket i changed (my seiT) had gone between a cylinder and a waterway - but your right, most of them i have changed have gone cylinder to cylinder..

Thanks again for all the feedback. Given the likelihood of further work I have decided to look into leasing a new car as I need something reliable for work and it seems likely I'll be paying lots in labour costs. The car is not going to its grave though, my dad is going to pay for the repairs advised by the garage (so as to be able to drive it to his - around 200 miles away - fingers crossed!) then he is a lot more up to speed with his cars and repairs so can do future work himself.
Really appreciate the feedback, helped me with making the decision of whether to throw money at it or go for the potentially more expensive but at least more reliable option of a lease!

fingers99 said:

Because it's only one cylinder. They'll almost invariably go over the shortest distance, which is between 2.

I suspect that the rings (at least) are shot on all 4, with possibility of valve issues on the lowest one.

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This is the classic 8V failure to me. Gases are escaping from cylinder to waterways causing overheating. I would not drive the car 200miles though as the problem seem advanced. I had this and my compression results were still showing OK. So this must be very advanced so quite risky to attempt 200miles. If you are brave before you depart with the car try re-torquing the head and bleed the system, you have nothing to loose.

i think he means his dad is gonna pay for the garage repairs and then collect it...

She means Ah really, I will pass this info on then thank you - I did wonder if it was a good idea to drive it that far without additional work, however the garage seems to think it will run ok once initial work done on it. However they specialise in a completely different car so I suspect may be less experienced with an old punto!

my apologies

Sounds like you've semi heat seized it, loss of power due to the heat building up causing the pistons to touch the cylinder wall's etc i wouldn't do the head gasket, just find a good second hand engine and get them fit that, it'll work out cheaper labor wise and parts.

GrandeGuy said:

Sounds like you've semi heat seized it, loss of power due to the heat building up causing the pistons to touch the cylinder wall's etc i wouldn't do the head gasket, just find a good second hand engine and get them fit that, it'll work out cheaper labor wise and parts.

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meaning the liners are more than likely no longer any use.

thelad said:

meaning the liners are more than likely no longer any use.

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There are no liners I think. Also the block is cast iron so has no problem with heat. The head will deform before repair before the block notices any heat issues if there is a problem with the cooling system.

its called wear

thankfully the fire engine is a good design with a few flaws but the future is lightweight rubbish built with aluminum blocks and its a one trick pony,once everything goes over the needle of doom (temp) everything goes into its non comfort zone and its scrap from piston rings that lose their shape to gaskets made of tin plate that causes heads and blocks to go banana shaped
welcome to the 21 st state technology
thankfully you will be able to look at this site in 20 years time and hanker after this old fashioned technology as you sit in your pod