1.4 8v TU3A KFV engine difficult problem

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Ady2021
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1.4 8v TU3A KFV engine difficult problem

Post by Ady2021 »

Earlier this year we were having lots of problems with my wife's Peugeot 207. It has the 1.4 8v TU3A KFV engine which I believe is the same one as they put in the older Peugeot 206. We were having problems with it loosing lots of water, overheating, excess pressure in the water and oil in the water etc. all the classic signs of a blown head gasket. I have since done the head gasket on it and there has now been no significant loss of water in the 10 weeks since I fixed it. When used for short school runs etc, the car now starts and runs lovely. The problem we are now having with it is when it gets a bit warm such as when it has been sat in traffic and then it sometimes cuts-out and then then struggles to turn over when you try to restart it. Prior to me doing the head gasket it had only ever shown symptoms like this once before and that was when it had lost all its coolant and overheated when on a day out.

I am scratching my head with this one. When it happens, the starter does sound significantly laboured like it would sound if the battery is flat. If you leave the car 5-10mins then it starts perfect again. It also starts perfect every morning even on the cold mornings or when it has been left for a few days. For some reason, that car really does not like it when the engine gets hot such as when it is sat in traffic. I did have a problem with the thermostat breaking on it so I have left the thermostat out and so a jammed thermostat is not the problem.

Part of me is wondering if the cylinder is somehow filling with steam or oil when it gets hot and is causing and hydraulic lock in the engine but then I have not seen any significant drop in water (and nothing like it was loosing before). Before I did the head gasket it was loosing lots of water (about 2 litres per week) but never had any problem starting when hot or cold. The only thing I have noticed is that we do have to top up the oil on it quite a lot but this could be due to to a bad crankshaft main seal that likes to drip anyway. Looking at the head gasket layout the oil would reach the water passage before it reaches the cylinder anyway and so the oil in the cylinder theory is doubtful.

Has anybody seen anything like this before? If it is not loosing any significant amount of water and there is no excess pressure in the coolant then surely the head gasket must be OK? I have wondered if the wet liners in the engine are sitting too low due to a worn engine and then the head is being lifted off of the lines when the engine block gets hot and expands.
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Huskyxantia
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Re: 1.4 8v TU3A KFV engine difficult problem

Post by Huskyxantia »

Sounds like the last part of your post could be the reason
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xantia_v6
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Re: 1.4 8v TU3A KFV engine difficult problem

Post by xantia_v6 »

I would suspect that the starter could be the problem.
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Huskyxantia
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Re: 1.4 8v TU3A KFV engine difficult problem

Post by Huskyxantia »

Were the pistons lose when you had the head off, and yes if the start seems slower that could be it , if the battery is good then it points toward starter.
Different car, but my old zx starter motor was slow when i brought it changed it with a refurb no problems.
Some cars can have problems with failing starters when they get hot .
Ady2021
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Re: 1.4 8v TU3A KFV engine difficult problem

Post by Ady2021 »

I initially thought the same myself that the starter was the problem but it works fine on the coldest days and was working fine before I swapped the head gasket. There is the added indicator that whatever it is it is enough to stop the engine when it is sat at tick-over such when it is hot and sat at traffic lights and then you have to sit and wait for it to cool for a few mins before you can get it going again.

I feel sure it is something to do with the head gasket still. The car only plays up when the car gets warm, ie when the pressure starts to build up in the cooling system and I winder if the pressure in the cooling system is exceeding that in the cylinders but I don't see how this is possible. I got the head gasket from my local motor factors and it was a BGA one which some people seem to frown about and have said that they swapped the BGA for Payen and their problems went away. I am also told that it does not really matter on these old TU3 engines.

I did take it in for its MOT the other day and it had a good run to the MOT centre and got a good test while it sat there getting hot while being tested. It failed miserably on the emissions but I guess the original leaking head gasket had wrecked the lambda sensor. When I got back and checked the water level, it had lost about 1-2 egg cups of water in all that time which is nothing like the 2+ litres of water it used to get through per week.

Is it true that the wet liners have to be shimmed to the right height with some kind of paper shim?
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Huskyxantia
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Re: 1.4 8v TU3A KFV engine difficult problem

Post by Huskyxantia »

Personally ive not heard of that maybe you do , going back a few years i had an xsara 1.4i the head was weaping front right corner it still drove , but it did damage the lambda sensor, if you can afford it get the head checked properly incase its warped or even cracked, but i will say this e10 petrol is cause all sorts of issues with older cars
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Huskyxantia
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Re: 1.4 8v TU3A KFV engine difficult problem

Post by Huskyxantia »

Liquid glass , ive used it, its on ebay, get engine hot by pass the heater matrix first then add full bottle let it work for couple of weeks then reconnect the heater matric pipes, it works aslong as your heads not to badly damaged
Ady2021
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Re: 1.4 8v TU3A KFV engine difficult problem

Post by Ady2021 »

Is 'liquid glass' the same stuff as 'liquid steel' head gasket repair stuff? Before fixing the head gasket I used that Holt Sealit stuff and that is amazing stuff for stopping head gasket leaks.
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Huskyxantia
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Re: 1.4 8v TU3A KFV engine difficult problem

Post by Huskyxantia »

Ady2021 wrote:
22 Nov 2021, 20:47
Is 'liquid glass' the same stuff as 'liquid steel' head gasket repair stuff? Before fixing the head gasket I used that Holt Sealit stuff and that is amazing stuff for stopping head gasket leaks.
Yes same stuff but not comercial named
ozvtr
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Re: 1.4 8v TU3A KFV engine difficult problem

Post by ozvtr »

Ady2021 wrote:
20 Nov 2021, 22:09
it had only ever shown symptoms like this once before and that was when it had lost all its coolant and overheated when on a day out.

when it has been sat in traffic and then it sometimes cuts-out

If you leave the car 5-10mins then it starts perfect again.

For some reason, that car really does not like it when the engine gets hot such as when it is sat in traffic.
I think that there is not enough coolant in the system. All of those are classic symptoms of low coolant levels in the engine and the engine is seizing up.
Yes, the dash temp probably doesn't indicate an engine over heat but that can be explained.
It will not hurt to drain and re-perform the coolant replacement procedure...pay particular attention to the bleeding process.
Fabricate a "header tank" on the expansion tank to expedite the bleeding process. I have found it hard bleed those engines properly if you do not use a header tank.
If I'm wrong...no harm done.
I know you have removed the thermostat but you should put it back in. Check it by putting it in a pot of boiling water and if it checks out, put it back in.

Be careful with liquid head gasket repair solutions, the wrong type getting into the wrong place will destroy your engine. Sodium silicate is the "liquid glass" a lot of manufactures refer to in head gasket repairs. If it gets into the oil, it will weld moving parts! I'm not saying don't do it, just be careful and "read the label".
Ady2021
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Re: 1.4 8v TU3A KFV engine difficult problem

Post by Ady2021 »

Thanks I will try bleeding it again. I need to change the coolant on it this week now that winter is starting to bite in the UK. I know what you mean about them being horrible to bleed but I have just about got the knack of using the 2 bleed screws now. As the coolant is being pushed out when the bleed screws are open then I have assumed that the water pump is working but there seems to be little other way to test that it is actually working.
Ady2021
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Re: 1.4 8v TU3A KFV engine difficult problem

Post by Ady2021 »

ozvtr wrote: Be careful with liquid head gasket repair solutions, the wrong type getting into the wrong place will destroy your engine. Sodium silicate is the "liquid glass" a lot of manufactures refer to in head gasket repairs. If it gets into the oil, it will weld moving parts! I'm not saying don't do it, just be careful and "read the label".
This is very interesting and could be what the problem is. I did put some of the 'Holts Sealit' stuff in before I fixed the head gasket and am now wondering if some of that stuff ended up in the oil and when it is getting hot it is trying to weld the parts together just as you say! Will give it another oil change to make sure it is all flushed out. You may have solved the problem!
Last edited by myglaren on 24 Nov 2021, 10:21, edited 1 time in total.
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ozvtr
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Re: 1.4 8v TU3A KFV engine difficult problem

Post by ozvtr »

Ady2021 wrote:
23 Nov 2021, 22:28
I have assumed that the water pump is working but there seems to be little other way to test that it is actually working.
Yes the water pump is another usual suspect.
If you are going to change the coolant anyway you can remove the upper hose (and thermostat but it's already out, right?) and run the engine for a few seconds and see if it pumps water.
The fins on the water pump can get corroded away or eaten by cavitation.
However this tends to give you an over temp warning on the dash. Low coolant sometimes doesn't register an over temp warning as the sensor may no longer be immersed in the coolant and it's just reading the air temperature.
There is an auxiliary sensor in the head that measures the actual cylinder head temperature of the #1 cylinder. If the head gets to 120'C it causes the coolant temp sensor to go open circuit and give a over temp warning. This may cause the engine to go into limp mode because it now has no temp sensor but I am not sure of that. It's possible this sensor is not working or your engine is seizing before the cylinder head is getting to 120'.
It's just a theory and a bit of a stretch to have all those ducks line up, but it's all I've got.
Ady2021
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Re: 1.4 8v TU3A KFV engine difficult problem

Post by Ady2021 »

Ok, coolant change done. I normally just fill up the expansion bottle, open the bleed screws and then run the engine and wait until all the air has finished coming out of the bleed screws. It proved to be an absolute pig to do this time however, the engine fan kept kicking in and still no water coming out the bleed screws (I hope I have not cooked the engine now). I ended up having to take the expansion bottle off and then hold it up as high as I could until the water had finally made its way into the engine. I assume you are going to tell me that this is the proper way to do it and you can bleed the cooling system with the engine cold.

I have now noticed another problem with it in terms of when it gets hot there is smoke coming out of the exhaust which does smell like it is burning oil (oil level is dropping too). I have checked it when it starts up from cold and it is absolutely fine with no smoke on start up and so the valve seals must be ok. I guess it must either the piston rings or oil is finding its way into the cylinder through the head gasket (considering it is a wet liner I assume the oil would end up in the coolant first though. Either way it is starting to look like there is little point investing much more money in this engine.

How long does a TU3A engine normally last? Is 115k miles about right for the lifespan of this engine before they start burning oil?
ozvtr
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Re: 1.4 8v TU3A KFV engine difficult problem

Post by ozvtr »

I am due to do the head gasket on my C3 and I am not looking forward to it. It has an oil leak behind and just above the alternator.

The thing that concerns me about these engines is the O-ring seals at the bottom of the liners. They are there to form a seal and stop coolant leaking into the sump. They should cause the liners to sit above the level of the lip of the crank case when the head is removed. Then they should be squashed down to form a seal against the bottom of the crank case and force the liners against the head gasket, and head, when the head is put on. But this fact is rarely, if ever, mentioned in the head gasket change documentation. How do you tell if the O-rings are worn and require replacing? If they don't form a tight seal against both the head gasket and the crank case you are in trouble.

There are many failure modes of the head gasket. Coolant into the cylinders. Coolant into the oil. Oil into the coolant. Oil into the cylinders (depends on the engine). Oil to the exterior of the engine. Coolant to the exterior of the engine. And combinations of all of these!!!!

You would have to be suspicious if the engine was not burning oil and then suddenly started burning oil.

Classic reason for the engine burning oil is failure of the piston oil seal rings. Inspect the spark plugs and see if there are oily or crusty deposits.

You can bump up the oil weight, the TU3 engines are not super dependent on oil viscosity. However the ET3 WOULD be.

Yes you can do the coolant flush cold by fabricating a header tank to raise the level of the coolant and therefore the "head pressure". It's basically doing the same as raising the expansion tank (as you did).