Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
[Engine] Head gasket or not?
Got a problem with my '08 Citroen Berlingo van, 1.6 Hdi engine. It's showing 91,000 on the clock. When I was checking it over after buying it a few months ago I noticed there were globules of oil (not emulsion) on the expansion tank cap. I kept an eye on the water level and found it needed frequent topping up, but there was no sign of overheating. In fact the gauge hardly moved if it was left ticking over and the top and bottom rad hoses were cold. I then found the cooling system was pressurising very quickly when starting from cold and the water was being pushed out of the expansion tank cap. My obvious thought was head gasket, but I thought it strange it wasn't overheating. When the driving the temp gauge will eventually come up to normal, sometimes go up to ¾ and then drop quickly back to cold, the heater will be blowing cold even when the temp is up, this seems to be due to the system airlocking. I fitted a new expansion tank cap and put a bottle of K-Seal in (via the top hose as recommended if the system is pressurising). This made no difference, but weirdly when running it up after putting it in the temp gauge went up to max, the 'STOP' light came on and the fan cut in, although the rad hoses were cold. I switched off and the fan was still running, I had to disconnect the battery to stop it. I then fitted a new thermostat as I thought maybe the running cold was a separate issue but it made no difference.
At this point I bit the bullet and booked it in to a local garage, they tested it and say it's not the head gasket, they think it is a circulation issue and first said they suspected the radiator. Then they said the flow through the rad was fine and it could be the water pump. They have now changed that... and it's still the same. The garage is now closed until the new year when they are going to look at it again.

I still suspect the head gasket but the garage seem sure it isn't that, so what am I (and they) missing?
Could be a crack in the head or cylinder jacket. I'd get the coolant tested for combustion gases.

If gases are found, either the head gasket, head, or cylinder liners are leaking. The HDi is a cold runner anyway, very thermally efficient, but pressure in the water system is never good when cold. It can't be the water pump, when cold it's at atmospheric pressure.

Any extra pressure when cold, has to be coming from the cylinder compression.
My Van: 2012 B9 1.6 HDi Enterprise
I called into the garage yesterday and had a chat with the guy working on the van, he said he had done a pressure test and a combustion gas test. I don't get it.
(05-01-2021, 05:52 PM)RattyCortina Wrote:  I called into the garage yesterday and had a chat with the guy working on the van, he said he had done a pressure test and a combustion gas test. I don't get it.

Have you simply been topping up the car without thoroughly bleeding the system of all air? It can be quite involved and ideally done with a (home made) header tank. My petrol Berlingo will show all of the same symptoms of STOP, cold pipes, cold heater etc. if the system is simply filled from the cap and not bled/vented. There may be bleed points at the 'stat housing, heater pipe inlet at the bulkhead and these need to be opened, along with the system run 'open' so that the coolant/air expands and vents into the external header tank ( a White Spirit bottle with the bottom cut out ).  It may take a couple of goes and works better with the car pointing up hill too.
The guy seemed to be aware of the venting issues when I mentioned it, but I don't know whether he has tried it. It's a bit difficult as I don't want to to seem like I'm teaching him to suck eggs, but I just want my van sorted! I did bleed the air at the vent on the 'stat housing but wasn't aware of the one on the heater then.
Some can be a real pain to bleed properly.
On the 1.4i, you're advised to jack up the front left corner quite a bit because the galleries in the engine block and head are higher up than the bleed screw on the thermostat housing, and there's a low point between them, too. And there's 3 bleed points; on top of radiator, thermostat housing, and where the hoses connects to the heater.(unless the car has an AC of course)

I don't know the 16 Diesel, but...
Air can be trapped in the strangest of places, and head gasket work tends to trip most of the air trap issues.

K-seal and similar are emergency use fixes only. As in, 'need to drive someone to the hospital, NOW' emergency. They can plug narrow galleries and hinder proper cooling in parts of the engine. Even dropping a raw egg into the radiator is less harmful than those ... chemicals...

If you can get access to an Infrared camera you might even be able to see where it's overheating...
Right, an update...

I rang the garage yesterday morning, the mechanic had taken the thermostat out and driven the van around (bearing in mind the garage is in a residential area so he would probably only have been doing 30), he said it was much improved, wasn't pushing the coolant out, the temp gauge was sitting at 70 degrees and the heater was blowing warm. So I collected it thinking it was at the very least usable even if running without the 'stat in wasn't ideal. This morning I went out in it to get my Mum's shopping as usual, 40 and 50 mph roads, the gauge just about got off the cold mark, may have briefly got up to 70 but the heater was cold. It's 4 miles to the supermarket, got there and when I got out there was a pool of water under the O/S of the engine bay, EXACTLY as was happening before. Did the shopping, went off to my Mum's, gauge went up nearly to the red, heater still cold. I was at my Mum's maybe 45 minutes, set off back home, gauge went right into the red and 'STOP' light flashing. Pulled over when I could and lifted the bonnet, rad and hoses stone cold (With no 'stat in I would have expected them to be at least warm?), heater hoses were warm, fan was running. Carried on home with gauge in the red and 'STOP' light on, engine was losing power but by this time I was really bothered if it seized TBH. Got home, fan stopped when I switched off.

So that's where I'm at. I am a bit loathe to scrap the van as otherwise it seems fine and it's a pain finding something else. Just had a quick look on youtube at bleeding the system, I think I will try it. I might refit the old thermostat/housing first as it doesn't seem that removing the 'stat has made any difference.
It's worth trying to fit the thermostat and park with the header tank up hill a bit, or raise the front, fill it up and run it with the cap off - let it warm up and expand the coolant. Air expands more than water, so it should purge itself after a while of running with the cap off. Keep an eye on the gauge, top up as needed, have the heater on full temp and fans medium, see if big burps of air come out. It could just be a bad airlock.
My Van: 2012 B9 1.6 HDi Enterprise
As Zion says it's almost certainly an air lock. But, if you just run it with the cap off the air will expand dramatically and shove a great gollop of coolant, peeing everywhere, along with some of the air, which will then contract and suck even more air back into the system. I'd suggest .....and it's the ONLY way mine will fill properly, with a working heater.
Re-fit the thermostat. Get a container of at least a litre, the neck of which fits inside the filler neck and cut the bottom out. Wrap foam tape/gaffer around the neck and push it into place, making sure that the overflow hole is blocked (or put mole grips on the plastic pipe). Fill the system with water and open the vents until water stops coming out.
Start the engine and let it warm up on its own, probably 5 minutes - during that time open the vents and let water flow out. I found that the heater vent appears to be on the suction side of the pump, so may actually allow air in when the engine is revved. With vents closed steadily increase the revs and the coolant will eventually gush into the bottle, followed by air. Stop revving and the coolant will disappear.
Do this a number of times and then stop the engine, let it cool and then top up to the normal level.
You may need to purge the system like this more than once, but once done it stays where it should be. A complete pain to do, but the only way mine would work normally. If you are worried about antifreeze I do the 'top up' with antifreeze, having done the initial purge with water.
I believe that Citroen had a filler 'funnel' that fitted/locked onto the bottle neck that was used for this purging process. It allows the trapped air out but saves the coolant and allows it to be drawn back in.
[-] The following 2 users say Thank You to oilyrag for this post:
  • RattyCortina, Zion
Thumbs Up 
That's a very good description of how to do it oilyrag, without using a header tank like you describe coolant will be gushing all over the place.  

Can anyone confirm if it's possible to remove & replace the thermostat in the plastic housing fitted to the 1.6hdi, is it not built in so to speak?

My vehicle .... 2006 (m59) Berlingo Multispace Desire - 1.6 HDI 92 

Forum Jump:

Users browsing this thread: 1 Guest(s)
You have to register before you can post on our site.



(Advanced Search)

Latest Threads
Front doors wind air deflectors
Last Post: ffrenchie
Today 09:19 AM
» Replies: 2
» Views: 242
Last Post: my mucker
Today 09:07 AM
» Replies: 3
» Views: 371
Thermostat housing vent
Last Post: saskak
Today 09:06 AM
» Replies: 1
» Views: 27
Greetings from Denmark
Last Post: my mucker
Today 09:01 AM
» Replies: 6
» Views: 333
Speedo and rev counter
Last Post: oilyrag
Today 08:43 AM
» Replies: 10
» Views: 500
Turns but doesn’t start 2.0hdi
Last Post: runningman
Today 07:05 AM
» Replies: 0
» Views: 54
Main beam on permanent - BSI?
Last Post: Zion
Today 06:18 AM
» Replies: 1
» Views: 72
Timing snapped
Last Post: Rasputin
Today 02:59 AM
» Replies: 26
» Views: 2469
Citroen TV ad
Last Post: Rasputin
Today 02:43 AM
» Replies: 1
» Views: 239
Berlingl0w - B9 Berlingo Lowered on 19’s
Last Post: djewen
Today 12:50 AM
» Replies: 120
» Views: 22535

Recent Visitors
Locations of visitors to this page