Technical Punto engine overheating

[salacious]

Howdy chaps,

I have a technical question regarding my 1996 (I think -- it's a P reg anyway) Punto 55. Basically, after 3 miles or so the red engine temperature warning light appears on the dash. Initially I thought my coolant level was low, so I filled it up. Unfortunately, that doesn't appear to be the case. The oil level is also good. The car was serviced about 3 months ago.

The coolant does get VERY hot, but doesn't seem to get noticeably lower. The main fan does not seem to ever go on.

I had a friend look at it and he suspects the head gasket has gone, but I thought one usually got a smoky exhaust and oil in the coolant? I can't see any in there, but that's not to say there isn't.

Any ideas of what the problem might be, or any ways to ascertain the problem, are much appreciated.

Also, if it IS the head gasket, am I better off getting it repaired, dropping a new engine in or scrapping the car?

 

[VII CKS]

First you need to check your fan, replace the fan switch. If the fan isnt kicking in it can cause the car to over heat. Where does the needle go on the dash, to the top? When you drive normally does it sit around the first mark?

To be honest what it sounds like to me is when you have filled up with coolant you have got an air lock in the system which can cause it to overheat. You need to bleed the coolant system from air locks.

Headgasket symptoms can be, misfiring, poor running, over fuelling, guzzling petrol, guzzling oil, guzzling coolant, pressure from coolant tank cap when released even when engine is cold, like a back rush. If not have you checked the oil cap? coolant cap? if so is there any colour on it, like a white milky substance? Does the exhaust smoke, does it give off white smoke? If it does give off smoke is it any other colour?

 

[salacious]

Hi VII CKS, thanks for the reply.

First you need to check your fan, replace the fan switch. If the fan isnt kicking in it can cause the car to over heat. Where does the needle go on the dash, to the top? When you drive normally does it sit around the first mark?

I'm afraid that my car is one of the older ones and I don't have a dial as such reflecting the engine temperature -- I just have a red light which illuminates when the engine is too hot. Bit of a design flaw, really. If the engine fan itself is borked, could it cause the whole thing to overheat within a couple of miles? The fan doesn't go on at all, and I would have thought it should with the engine being that hot! The coolant does get very hot.

To be honest what it sounds like to me is when you have filled up with coolant you have got an air lock in the system which can cause it to overheat. You need to bleed the coolant system from air locks.

I will seek advice on how to do this. The car was recently serviced and I would hope that they filled up with coolant properly.

Headgasket symptoms can be, misfiring, poor running, over fuelling, guzzling petrol, guzzling oil, guzzling coolant, pressure from coolant tank cap when released even when engine is cold, like a back rush. If not have you checked the oil cap? coolant cap? if so is there any colour on it, like a white milky substance? Does the exhaust smoke, does it give off white smoke? If it does give off smoke is it any other colour?

Your response here is what makes me question the analysis of borked head gasket. The engine does seem to stutter (misfire?) a bit when started, but I haven't noticed any other performance issues. The petrol consumption is normal, it's not guzzling oil etc. I will check to see if there is pressure from the coolant tank cap and whether the coolant is milky -- although I'm fairly certain that it isn't. I will also double check the exhaust, although again I'm fairly certain it isn't white (or any other colour).

Thanks a lot for your reply, and I appreciate any further thoughts.

 

[VII CKS]

First the issue sounds like your fan, I don't know if you are into wiring but the best thing to do is wire up to the fan a switch that you can use in the car to just override it momentarily until you sort the problem out, put an inline fuse in as well. Everytime you drive the car, switch the switch to enable the fan to run, even constantly it will protect the engine from overheating. If it is overheating chances are it is going to warp the headgasket. Otherwise if you cant do this quickly, then DO NOT DRIVE THE CAR, you will bake it!

To be honest check the fuses, and perhaps get a fan switch. To be honest invest in this: http://cgi.ebay.co.uk/Radiator-Fan-...ItemQQimsxZ20090622?IMSfp=TL090622149005r1462 if you can't do the temporary solution as above do not drive the car until you have this switch, it's a common problem and causes the car to over heat.

Then when that is sorted, check your coolant levels, keep an eye on it, but do check there are no airlocks in the system.

To be honest if a car is overheating it generally runs rubbish anyway, and also you may want to consider changing the CTS, this is the coolant temperature sensor, these can deteriorate overtime causing poor running etc, it sends the information to the ECU on temperature etc. These can be picked up for about £5-10 and fitted easily with just a deep socket set or spanner.

Have you checked the colour of your spark plugs? It's a 10mm deep spanner IIRC for a punto, take them out, one by one, the colour can be an indication of something more sinister, or can tell you if they are correctly matched with the car. Were they changed in the service? If not perhaps you should invest in changing those? If you don't clean them with a wire brush (spark plug brush) and check the gapping with a feeler gauge (measurements are in the Haynes Manual).

 

[Punto_2008]

I had the same problem about 6 months ago on my 55s, and i needed a new cooling fan from the scrappy. Cost me £20 for a fan from the scrappy. I took the motor of the old one apart to find that all the parts inside had fused together with heat. I've got a both the switch and fan on the car as i'm now breaking it. If you want the switch, you can have it for £4 including postage and the fan you can have for £20 including postage if you need them. PM me if you're interested. You can test the fan on the car by taking the connector off of the switch which sits near the bottom of the expansion tank and then bridging the terminals of the connector. The fan should then switch on as the circuit is complete (MAKE SURE NONE OF YOUR CLOTHING OR ANYTHING IS DANGLING IN TO THE FAN OR NEAR IT). If not, the fan is to blame. If it works, then check for airlocks, bleed the system using the bleed screws at the top left corner of the radiator (looking at the front of the car) and the pipe that goes through into the car down the back of the engine in the middle. If that still doesnt work try a different switch. Good luck

 

[salacious]

Thanks to both of you for your responses. I will investigate the fan tomorrow and see if that is the problem, and then report back.

Punto_2008 -- if the parts I have are faulty I would definitely be interested in taking those bits off your hands. I will report back tomorrow with my findings!

Thanks again.

 

[PUNTOELXBERTONE]

It wont be the fan as it wouldnt heat up that quick, it sounds like the thermostat not letting the water into the engine. and could be a leak in the system even if you dont see water it doesnt mean its leaking. They is a Sensor on the radiator for the water, once it reaches a certain temp it will kick in. If it was the Head gasket you would notice a difference in performance and also white residue in the oil cap.

 

[VII CKS]

Any news?

Both of the guys have a point above. When was the thermostat last changed? You can actually take it off and test it in a clear bowl of hot water to see if it is working, to be honest they are only around a tenner to replace anyway, and make sure you replace the gasket on it at the same time.

But something seems strange if the fan actually isn't working. I'd just replace the fan switch. If not investigate whether the thermostat is working. If that is, have a look at the CTS.

 

[richie.guy]

Overheating after 3 miles is not only a fan issue IMO, although it maybe A problem.

Airlock, lack of coolant, broken thermostat, blocked rad IMO

Could also be a failing water pump - not flowing enough water and putting air into it at the same time.

3 miles no time at all to cook 4-5 litres of water. Should take much longer than that to get up to temp, let alone overheat.

 

[salacious]

Right, I haven't investigated as fully as I would like (get a bit baffled by engines, hoping to gradually rectify that) but here's my report thus far.

I opened the bonnet, and unscrewed the water cap. It DOES seem low (filled it up on last overheat, drove about 3 miles on it, not checked since), and it may be cloudy but I can't be sure (oil got in?).

I checked the oil level. It's normal. I checked under the oil cap/plug, there is no white residue.

I started the engine and ran it for about 60s. There was no smoke, white or otherwise, from the exhaust.

However, the engine had already got very hot. The radiator did not seem warm at all. The fan did not spin (although I don't think I would expect it to). One interesting thing (maybe) is that the coolant hissed when I unscrewed the top, and was steaming slightly. This surprised me as the engine hadn't run for long, but I don't know whether this is normal.

 

[salacious]

Overheating after 3 miles is not only a fan issue IMO, although it maybe A problem.

Airlock, lack of coolant, broken thermostat, blocked rad IMO

Could also be a failing water pump - not flowing enough water and putting air into it at the same time.

3 miles no time at all to cook 4-5 litres of water. Should take much longer than that to get up to temp, let alone overheat.

I will definitely pass this info on to the guy who's going to work on the car -- I'd rather he check this stuff before replacing a healthy head gasket. If it is healthy. Which it might not be

 

[spf]

Right, I haven't investigated as fully as I would like (get a bit baffled by engines, hoping to gradually rectify that) but here's my report thus far.

I opened the bonnet, and unscrewed the water cap. It DOES seem low (filled it up on last overheat, drove about 3 miles on it, not checked since), and it may be cloudy but I can't be sure (oil got in?).

I checked the oil level. It's normal. I checked under the oil cap/plug, there is no white residue.

I started the engine and ran it for about 60s. There was no smoke, white or otherwise, from the exhaust.

However, the engine had already got very hot. The radiator did not seem warm at all. The fan did not spin (although I don't think I would expect it to). One interesting thing (maybe) is that the coolant hissed when I unscrewed the top, and was steaming slightly. This surprised me as the engine hadn't run for long, but I don't know whether this is normal.

definitely sounds like an airlock / water pump / blocked rad. If it's overheating that quickly there's no water moving through the engine block.

Had the same syptoms recently, was an airlock, which was caused by a loose hose connection which was pulling air into the system. Don't drive the car until it's sorted and chances are it won't end up being major work. There's a guide for bleeding puntos in the guides section, well worth trying out the procedure imo.

 

[MikeSalt]

3 minutes is the sort of time you would expect the thermostat to be opening and letting hot coolant out of the engine and into the radiator. Does the radiator get particularly hot at all?

 

[salacious]

3 minutes is the sort of time you would expect the thermostat to be opening and letting hot coolant out of the engine and into the radiator. Does the radiator get particularly hot at all?

In the 60s I ran the car earlier the radiator didn't seem to be hot whereas the engine itself did. I didn't check it when I ran the car for longer and originally noticed the problem.

 

[PUNTOELXBERTONE]

I had the same problem with my punto cabby, loosing water but didnt know where from, it was leaking out of the radiator, just slightly steaming and loosing water, but previously was the thermostat, got that hot the waterpump went, and water was coming out of the waterpump. so got that replaced as well as the thermostat and alot timing belt done. all in all cost me about 150quid for

Waterpump,
Thermostat
timing belt and tensnor,
New Radiator,
New ht lead as they had melted due to the engine getting that hot
Was all fitted by a back street garage, drives like new now

 

[salacious]

OK, well I've spoken to the chap who's going to be working on the car and let him know about all of the comments here. The car is going in next week for work.

You guys have all been great, kinda puts your faith back in humanity. I'll let you know what the problem(s) was and how it was fixed.

 

[PUNTOELXBERTONE]

Well if you need any help am happy to come round and look at the problem? were abouts are you?

 

[salacious]

Well if you need any help am happy to come round and look at the problem? were abouts are you?

Southampton. Not exactly round the corner! But many thanks for your offer.