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Discussion Starter #1
Hi All, Fairly new to the forum, which I think is great by the way and just after a bit of advice or finding someone thats had a simalar problem.

I have got a 1995 espace 2.1 turbo diesel and brought it with suspected head gasket failure due to the cooling sytem over pressurising.

I have changed the head gasket also fitting a new water pump and thermostat and expansion tank cap but I still have major pressure and loads of air bubbles in the cooling system. So much pressure that after a 10 mile drive it will blow the top hose off the thermostat housing.

It warms up from cold fairly quickly, about five mins sat at idle but does not overheat.

I have bled the cooling system at the top of the rad and at the heater hose bleed screw just by holding the header tank higher than the heater and also by pressurising the system to 5 bar so I do not beleive there would still be any air locks in it but I might be wrong.

I have pressurised the sytem to 5 bar and it held for over 10 minutes with no pressure loss whatsoever.

The only thing I can think is either the head is cracked (I did not have it tested like a pratt when it was off), the liner seals have gone or I have a blockage somewhere (even though I have flushed the system) and the poblem is only showing up when the sytem is hot.

Any ideas or suggestions would be greatly appreciated especially if someone has been here before.

Sorry to have waffled on but I just wanna get all the facts in from the start.

I have also tried steel seal to see if it improves anything but it had no effect whatsoever so I have flushed that back out of the system.

Only thing I havent yet done is the sniffer or block test to see if there are exhaust gases in the coolant cause the mot and tax have run out and I cant get it to a garage for the test to be done. I obviously dont wanna mot & tax it till its fixed.

Many thanks,

Nige
 

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Re: 1995 Espace 2.1TD pressurising colling system

Hi I think you have got to do a sniff test as it sounds like a cracked head, but just a thought have you changed the rad cap as it should not get enough pressure up to blow hoses off it might be the wrong one even
 

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Discussion Starter #3
Re: 1995 Espace 2.1TD pressurising colling system

Cheers for the reply.

The more I think about it the more I think the sniffer test is the way to go.

I have tried 4 caps, the origional one, a known good one off my old 21 Savanna, and 2 new ones from different suppliers and all are giving the same outcome.

Only prob with the sniffer test if I do get it done is I still wont know if its the head or the liner seals etc????????????
 

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Re: 1995 Espace 2.1TD pressurising colling system

Right then I managed to get my hands on a sniffer test kit and have just done it.

The die stayed blue!!!!!!!!!!

I waited for the system to get hot just letting it tick over and once the stat had opened took the expansion tank cap off and held the test kit tube with the die in in the top of the tank. A few bubbles and no change of colour, so I gave it a few revs up to about 3 grand and it blew a load more bubbles and a little coolant into the test kit tube and die but the die stayed blue so I am presuming that there is no trace of exhaust gasses in the coolant.

After the test I put the expansion tank cap back on, took the car a quick blast round the block and only then did the top hose get hard and the sytem pressurise again.

When I was waiting for the system to initally warm up before the test once the thermostat opened the rad got nice and warm but seemed to take quite a while for the bottom of the rad and the bottom hose to warm up. It eventually did warm up and once I had been for the run was well and truly warmed up and pressurised like the top hose.

This has left me wondering if there is a blockage somewhere in the rad itself that is slowing the water flow down and causing the pressurising. Does this sound feasible?

I am pulling my hair out now trying to think what the hell could be causing the pressurisation????????????????????????????????????????

Any ideas on a postcard please lol???????????????????????????????????????????

Nige
 

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Re: 1995 Espace 2.1TD pressurising colling system

Hi again you could be right with the radiator but with what you are saying it could be the water pump as for checking if i remember corectly it has a small bleed hose coming from the head or the thermostat housing if you take this off you should get a little at tickover to a good streem when reved up, good luck
 

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Discussion Starter #6
Re: 1995 Espace 2.1TD pressurising colling system

I take it you mean the hose that runs accross from the thermostat housing to the expansion tank? If thats the one, it does exactly as you say cause I can see it pumping into the expansion tank.

I had got thinking about the water pump yesterday after someone at work was on about one with the impeller put on backwards once cause that could cause the system to cavatate and pressurise but after thinking it through the water your on about pumping through that hose back to the expansion tank wouldnt happen if this was the case would it?

I am gonna do the sniff test again tonight or tomorrow just incase I got a false reading. I have got the pressure tester to run that again hot and cold. If I cant get any results from either of those then I am just gonna start pulling each hose off in turn and checking them over then back flush the rad again, change the stat for a hotter one and see what happens. if none of that proves any good then I just gotta decide if I pull the head again or just bang another engine in. Recon head or second hand engine with warranty around the same price but I am thinking less work to swap the lump as a whole.

Its just really peein me off now not havin a clue whats causing it.
:steam:

Nige
 

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Discussion Starter #7
Re: 1995 Espace 2.1TD pressurising colling system

Well after a bit of an eventfull weekend with the siter in law thinking she had gone into labour and an all nighter at the hospital last night I finally got to have a couple of hours on the Espace this afternoon.

Like a pratt i had left the fluid out of the sniffer test kit at work so I couldnt do that one again but I did do the pressure test again today.

I pressurised it to 20bar and held it there for 25 minutes when cold then again when hot and there was no sign of leakage whatsoever.

At around 15 bar the hoses feel about the same pressure as they do when the system pressurises itself. so I am guessin that the sort of pressure its reaching on its own.

I am still thinking I have got an air lock somewhere though. After I had finished the pressure test I slowly started to unscrew the bleed off screw from the heater hose and it made a farting noise before peein water out round the screw threads under pressure and still making a hissing sound as if there was loads of air in it.

Unfortunately I had no access to water at the garage this afternoon so I couldnt carry on bleeding it but it does seem to me like there is still a major air lock in there which I cant understand cause I origionally bled the system with the bleed screw right out untill what seemed like air free water was flowing from them.

I am either letting the lack of sleep over the last 24 hours catch up with me now or have just come up with a perfectly viable answer to what is occuring.....I wonder if there is a crack in the head water jacket from one of the inlet ports that is only opening up under boost pressure from the turbo therefore drawing in fairly clean pressurised air and pressurising the cooling system without letting any water escape and very little exhaust gas getting in therefore filling the system with pressurised air bubbles kinda like a soda stream if you remember them and not giving out enough hydro-carbons to trigger the original sniffer test.

DOes this sound viable or am I just drifting off to sleep and trying to convince myself I have an answer to the problem????????????

Nige
 

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Re: 1995 Espace 2.1TD pressurising colling system

If it's pressurising then you either have head gasket failure (again) or the heads cracked/porous.Theres no other way (in my experience) that a system will show signs of excess pressure.
 

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Discussion Starter #9
Re: 1995 Espace 2.1TD pressurising colling system

If it's pressurising then you either have head gasket failure (again) or the heads cracked/porous.Theres no other way (in my experience) that a system will show signs of excess pressure.
TBH I think I have to agree with you mate. I think I am gonna have a ring round today trying to get a price on pressure testing and possible repair of my head then start the big dismantle later on.

Still tryin to work out if I would be better off just banging another lump in though.

Nige
 

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Discussion Starter #10
Re: 1995 Espace 2.1TD pressurising colling system

Well thats it. I have gone for it a pulled the head back off. I think I did pretty well seeing as I starter at 7pm and it was off by 9pm even if I do say so myself.

The head gasket had definately sealed well and there is no sign of it havin been blown again.

I just hope I have gone down the right path now and it does come up as being cracked.

I have phoned a place we use at work who will pressure test it for me for £30 and if it needs repair he said that if its a fairly straight forward one then that would be another £30 on top which I personally think is pretty good.

I just got the task of strippin the head bare now ready to send it off to the guy for checking.

Hopefully I will get that done tomorrow night after work.

I just gotta hope the pressure he tests it at shows up the crack if it is in the head.

Nige
 

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Re: 1995 Espace 2.1TD pressurising colling system

Blimey,you don't muck about do you?.:d

Any chance of a few pictures of the head gasket that came off this time and also of the head face?.

I hope the pressure test goes to plan,they aren't 100% bullet proof for finding cracks but it will be interesting to hear the outcome.
 

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Discussion Starter #12
Re: 1995 Espace 2.1TD pressurising colling system

Kinda gettin to know my way around it now lol.

I have got a couple of the head when it was off last time but will take some more later. They are all pretty low quality though sorry cause had to use my phone.

Dunno what I am gonna do if they say the head aint cracked though.

Nige
 

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Discussion Starter #13
Re: 1995 Espace 2.1TD pressurising colling system

Right then got a load of pics of the head and block upon removing the head and also of the head during and after stripping it.

I think the leak is on number 1 cylinder as the combustion chamber has light pitting/erosion from what I would imagine is water damage compared with the other cylinders and also if you look at the pics I have spotted what appears to be a small crack along the edge of the combustion chamber. It might not be though and might just be surface damage. Their appears to be a crack by one of the main water galleries too but I actually just think that is a mark from the origional surface grinding of the head.

Let me know what you think??????????

Their is some cracks in the inserts where the the injectors and glow plugs go into but I have been told that these should be ok.

Just waiting for the head to be picked up now by the engineering place.

Nige
 

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Re: 1995 Espace 2.1TD pressurising colling system

It looks like that head has been very poorly skimmed,I'll copy some of the photos (if you don't mind) and show you what I mean.

Back in a mo.:)
 

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Re: 1995 Espace 2.1TD pressurising colling system

The scores appear to be just that - possibly due to swarf during the original maching process. Cracks tend to either run from or to holes or cumbustion areas. Rarely are they straight or have a geometric shape.
As you say number one cylinder has had more than its fair share of water. I also notice what appears to signs of pitting or gasket failure on number 3 cylinder.

As a matter of interest what was the injector like from number one cylinder - any signs of damage or missing bits?:)
 

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Re: 1995 Espace 2.1TD pressurising colling system

Heres the obvious thing I can see in one of the pics....



The two lines I've highlighted in green are scores caused by a poor skim at some time in it's life,they go right across the area where the fire ring in the gasket sits (marked in red) and although they don't look like much they will definately cause compression pressure to escape from the cylinder.The discolouration on that combustion chamber is a definate sign of a problem too.

You could have the head skimmed again,but you might be running very close to having piston to valve contact even using the thickest gasket you can get so the head might be junk.

I'd wait to see what the engineering shop say,but I'd say from looking at a few of the pics that your looking at a new/replacement head.
 

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Discussion Starter #17
Re: 1995 Espace 2.1TD pressurising colling system

All the injectors are fine. I have got full service history for the vehicle and every receipt for anything its ever had all in a folder, even down to every fill up with fuel and cant find trace of any head gasket or coolant issues previously in its life other tan a thermostat, temp sensor and antifreeze changes so I guess it must have been that way from new. I have got some close up shots of each cylinder.......they are in order 1,2,3,4, then the same of the block.

No 3 had a little rust mark on the cylinder wall at the top of the piston like damp had been in there when i took these yesterday after the head had been off 24hrs which suggested water ingress to me tbh, I have just soaked it all with wd40 for now to stop it causing any damage. The water could have got in there when i lifted the head.

So whats the verdict then? Scrap the head and get another one or see what the machine shop say?

Nige
 

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Re: 1995 Espace 2.1TD pressurising colling system

If it's not been skimmed before then you might get away with it,but I would put good money on it having been apart before.

These are the areas that would concern me....









...in fact,the more you look at the pics the more you can see to be honest.

I'd still have it pressure tested,but I would definately get an engineering shop to look at the head face and if they say it hasn't been skimmed before,have it done.

I'd also check the tops of the liners,the pics are a little blurred to see anything but they need to be spot less.Any marks in them and that will add to the problem.The area where the fire rings in the gasket sit need to be perfect and without flaw,even the smallest thing there can cause the gasket fail in no time at all.

I am slightly concerned about the pitting in that one combustion chamber though,water/coolant will usually just clean a chamber up or at least cause it to discolour,the fact that this one is pitted would worry me.
 

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Discussion Starter #19
Re: 1995 Espace 2.1TD pressurising colling system

Tbh it is more discolouration than any pitting. If you run your finger nail across it it does not feel any worse than the other 3 but I guess i will just have to wait and see.

The tops of the liners are mint with no marks or pitting whatsoever.

The cheapest I have seen a head for is £225 delivered, which is stretching the old budget a bit.

Guess I will just have to wait and see what the verdict is.

The Haynes manual says these heads cant be skimmed so I dunno weather to have it done or not. Its already on the 3 hole (thickest gasket but I aint got access to a dti guage to measure the valve to piston clearance or piston protrusion its just the gasket the motor factors recommended cause I did not know the thickness I needed.

It ran lovelly when I fitted the last head gasket with no knocking or loss of power or anything. The only issue was the pressurising coolant.

I have only cleaned the head face with a scotch brite and brake cleaner to polish it up so it may just need a bit of 1500 wet and dry or something to shift some of the more stubborn marks maybe.

The lines from the surface grinder that are on the head face dont feel deep and are hardly noticeable in real life. Like you say the camera is not the best quality so it makes things seem worse tbh. The worst bits are the cracks which I origionally pointed out earlier. These are really noticeable.

Nige
 

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Discussion Starter #20
Re: 1995 Espace 2.1TD pressurising colling system

Well the head was picked up by the engineers today so fingers crossed I get some good news in the next few days. I will kepp you posted.

Nige
 
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