406oc.co.uk

good morning all thought Id just update everyone on my water loss ...
I decided to bite the bullet and do the head gasket .Because its bloody freezing outside and i have to work out there .I took my time but I found the job to be really a lot easier than led to believe I have it all stripped now ready for a clean up then re-build .Im not good at doing write ups but I have taken quite a few photos of the process and am more than willing to share/advise on what ive learnt along the way .if all goes to plan should be back on the road by monday

hope it all goes to plan mate. let us know how u get on when its completed

Hi Wizard,
It looks like I am following you with your symptoms. My 2002 406 2.0 HDI is loosing water at the rate of about half a litre every 100 miles. The car drives perfectly well with no loss of power, no smoke in the exhaust, no mayo on the oil cap, etc. When taking off the header tank cap there is always pressure in the cooling system. The local garage have pressure tested the cooloing system and can find no leaks. I feel sure that the HG has a small leak in it allowing cylinder pressure into the cooling system which then looses water by blowing past the filler cap. I am about to try K-Seal as a last resort. I am not confident this will work. If I have to do the HG I will wait until the weather warms up!

MPorter

k-seal is very good stuff for the right leak .
my mates 53 plate megane had a leak. i looked all over could not find a leak anywere at all
anyway it would loose a lot of water in a few days
i changed the thermostat . checked radiator numerous times and still could fine no leak

anyway i told him to go and get a bottle of k-seal from factors and stick it in see if that works. and guess what it has he looses no coolant anymore
even i couldnt beleive it

Hi there I also tried the K-seal .I removed the thermostat houseing to pour directly in to make sure it actually got to the head but no luck for me system still pressurised .i also had the hg test done and it was negative .I have got the hg and it doesnt show any signs of real damage ..only at cylinder one from the edge of the cylinder to the 2 water ways is black (carbonated ) so even though the gasket is complete it appears that it was blow by into the water system(thats the therey anyway) I need to get a new water seal (o-ring ) for the water manifold then I will finish putting her back together.
Ill update later if all goes well .

Personally, i wouldnt have used kseal. Used it couple times before and no joy either. I think i regretted using it cos it just goes solid & is a pain to flush out once the heads skimmed & back on.
I had a leaky hg on the 110 & pressure testing never picked up on it. Think it was a leak between 3&4 cylinder

OK all back together and system bleed through took her for a short run to get up to temperature .dark by the the time i got back so will leave her to sit over night and then do full check this morning .

how much did it cost you alltogether mate ?
did you have any experience in this job at all before you started it ?

glad its sorted now lets hope that water leak stops

well I ve done about 5o odd miles today couple of short trips stops and starts and all is looking good wont say deffo yet till i check again once fully cooled .but Im feelin good ...I will post the full cost later when ive totalled it all ..I will list all Ive done with cost prices and approx times and how easy/hard I found it .hope this might help others. its gonna be alot cheaper than a garage . I have done a head on a VW t4 1.9 td before but this was my first 406 that Ive done any serious work on ...I am based near worthing and am more than willing to pass on any info that ive learnt .
will follow up tommorow.

Ive got a feeling your write-up will go down well here. Pat on the back mate

Good morning all It is now 6days since I put the car back on the road and have done just over 200 miles and no issues .
the job took about 12-14 hrs in total over 3 days (due mainly to weather ) proberly take 4 hrs off that in good conditions .
i brought the head Gasket set with bolts from a company I used before at £63.00 inclusive of p&p.the head was in good condition and after checking for any signs of cracks or warpage i gave it a good clean with petrol .I used a haynes manual for reference but found that I didnt need to do a lot of the suggested work .once I removed the egr pipe work and the air duct to the turbo I found it fairlly easy to undo the exhaust manifold and leave the turbo and all in situ .I used a couple of lengths of 12mm stud bent at 90% to free the head as per the manual once free I lifted it forward and up at the same time .I am a better mechanic than I am at writting but if anyone wants to ask I will be happy to help as best as I can .I have taken quite a few photos of the process and if I can work out how I will upload for all to veiw if requested .A big thank you to all for the advise and support.

so did you have the head skimmed?

No it didnt require it I used a steel straight edge and checked for any fluctuations with feeler gauges .they allow 0.03-0.05mmm tolerance and it well within that .

did u not get it pressor tested

No it looked so good and being out of work Im working to a real tight budget .so i went for it .in all honesty the job turned out to be easier than I thought and the price of the parts it was worth the risk .to me any way . I would have had to be off the road for too long and i really needed to get her rolling so i can look for work.