Simon's new Xantia V6 and Leaf blog

[white exec]

Gosh, Simon, what a pig of what should be a straightforward job. Presumably fitting of the 'stat would have been a simple job, engine-out, at the factory?

I think Jim could well be right about history and previous unknown coolant history and usage. It is so easy for coolant to be neglected, especially by owners who do their own so-called 'maintenance'. This can include topping up with water (tapwater, even), mixing of coolant types, or simply failing to renew the mix - ever!

Citroen (and other) model history is littered with heater matrixes, radiators, aluminium housings, cylinder heads and water-oil heat exchangers springing leaks and needing replacement. Many of these are delicate items, which need all the protection they can get, via appropriate coolant. My guess is they often don't get it.

For your engine, I'd be going for the very best coolant ready-mix you can lay hands on, and renewing it on the nail. You can't do much more than that.

What a sh*tty job!

[CitroJim]

Gosh, Simon, what a pig of what should be a straightforward job. Presumably fitting of the 'stat would have been a simple job, engine-out, at the factory?

Simpler yes, if fitted before all else is fitted to that end of the engine...

I swapped one once when I had the engine out to do a gearbox... It was still not easy with all the ancillary items still in the way... Even then a lot had to be shifted...

[xantos]

Soooo what's Mandrake Moriarty doing? Probably swearing the sh** out of the V6 engine and all the French engineers...

Fingers crossed all goes well...

[superloopy]

Yup .... everythings x'd cos i'd not want Si to be taking a second day off work. Trust its all back together and he's sitting back relaxing now, worn out [emoji6]

Sent from my LG-D855 using Tapatalk

[CitroJim]

Yup .... everythings x'd cos i'd not want Si to be taking a second day off work. Trust its all back together and he's sitting back relaxing now [emoji6]

Same here!

[white exec]

He deserves a break. Hope the knuckles are on the mend, Simon.

[DHallworth]

I put a new thermostat in the V6 engine before it went into the Activa, I remember thinking at the time it would be a sod to do in the car as like Jim says, it wasn't a case of just dropping it in when it was on the engine stand.

I need to change the temperature sensor down there that feeds the dial, I've been putting that off for 18 months now!

Hopefully it'll all be sorted after this, Simon.

David.

[Mandrake]

Thanks everyone for the crossed fingers and well wishes, everything is back together and working just fine.

It was icy cold this morning but sunny and dry, I took my time and worked carefully so all up it was about 3 hours until I was ready for a test drive.

Assembly was fairly straight forward if awkward, and there were a few little things to sort out along the way, like broken mounting clips that hold connectors that had to be replaced with cable ties - the usual. I also found I had to adjust the gear lever cable mounting plate a bit, and the hydraulic lines that I had to bend out of the way a bit had to be bent back before I could get everything to line up!

In the process I spotted this:



Yes, a crack in the return hose. Bother! Fortunately it is only a crack on the surface at the moment so it isn't leaking, but if it was bent sharply I'm sure it would tear and start leaking everywhere. I checked my disassembly photos (pro tip - always take photos during disassembly ) and sure enough the crack was there in the photo before I started the job even though I hadn't noticed it at the time...

This caught me by surprise right near the end of the reassembly so all I could really think of doing was wrapping it tightly with a few layers of self amalgamating tape - not to stop a leak as it isn't leaking, (not sure the tape is oil resistant anyway) but more as a bandage/splint to stiffen it up and act as a strain relief to hopefully prevent the surface crack migrating into a full blown tear and leak until I can come up with something better...



I'm assuming that hose is NFP, so what is peoples preferred method of permanent repair ?

After assembly I filled and bled the system and then let it idle from cold with the coolant cap off. And idle....and idle.... in fact in these near zero conditions it took a full 15 minutes of idling for the temperature indicated by the Lexia to creep up to 82, (radiator stone cold the whole time) and right on the money the radiator hoses and radiator started warming up at exactly 82 degrees as reported by the Lexia.

I left it idling another 10 minutes but it never reached the low speed fan cut in temperature of 93 so I had to hold it at 2000 for a few minutes to get it there and confirm that the fans did indeed kick in at exactly 93, and then cut out again at 90. So all good on the fan control after reconnecting the cabling to the brown sensor that I had removed.

No leaks were evident so it was time for a half hour test drive, which somehow became a full hour! It got a variety of driving through slow areas, motorway etc with the Lexia in the background to compare temperature with the temperature gauge. Above 50mph I never saw a reading higher than about 88 degrees, at 30mph after doing motorway driving it would typically go up to 93 and back down to 90 after the fans kicked in and despite everything I threw at it I never saw a reading higher than 96 on the Lexia, and that was only for a couple of minutes after it had been driven hard then stopped stationary, but it quickly came back down to 90.

The dashboard gauge stayed between an indicated 75 and 85 degrees the whole time, tending to sit a needle above above the 80 mark most of the time. So on average the dashboard gauge reads about 10 degrees lower than the Lexia, but the differential between them does vary in both directions, and they do tend to rise and fall at different times since the Lexia measures the temperature of the water leaving the engine heading for the radiator (or bypass loop) while the gauge sensor reads the beginning of the loop where the radiator returns to, so there is a time lag between them.

I didn't put any Forte in this time - although there will still be some in there as I only drained and replaced 5 litres out of the 8 (?) litres in the system as the engine block was not drained below the thermostat level. So far the heater matrix is still not leaking with the fresh reduced Forte strength coolant.

I won't be putting any more in unless it starts leaking again, however I think with the corroding ledge issue sorted and a nice new thermostat and gasket it is probably safe to add Forte now - I think I was just unlucky to have a mound of corrosion for it to bind to, if indeed it did anything at all - it could well have been an unlucky coincidence.

So, a complete prick of a job to get it apart, but all's well that ends well and I now have the confidence that apart from a potentially leaky matrix which seems OK for now the cooling system is in good nick with a new radiator, new thermostat, fairly new coolant expansion chamber and yet more fresh new ready mixed coolant.

[Hell Razor5543]

That cracked pipe looks like a T piece, with a narrow short section of pipe, followed by a wider pipe. I wonder how feasible it would be (assuming you have a backup plan, just in case) to remove that short section of pipe and replace it with a good section of similar size and material of pipe?

[Mandrake]

That cracked pipe looks like a T piece, with a narrow short section of pipe, followed by a wider pipe. I wonder how feasible it would be (assuming you have a backup plan, just in case) to remove that short section of pipe and replace it with a good section of similar size and material of pipe?

Yes it is a T-piece - I should have posted a slightly less cropped image - it is in fact the overflow return from the pressure regulator which tees to the overflow return from the hydractive electrovalve (that's the one that has the split) before changing to a steel pipe that runs beside the battery back to the tank.

A known point of failure on the V6 from what I've read elsewhere on the forum. I suppose a possible repair is to cut the T out and replace it with a stainless steel T joint and three fuel line style hose clamps - not sure what inside diameter the pipes are to order one ahead of time though, and whether they're even all the same inside diameter as each other ?

[RichardW]

It's not listed as NFP yet....

Part Number Description Quantity Price excl. VAT Price incl. VAT Total incl. VAT Selection
00005270FA OIL BACK HARNES 36.97 GBP 44.36 GBP 44.36 GBP

[white exec]

If it's only a low pressure return, and a single crack, and the rest of the tee is ok, then cut the pipe at the crack, and internally sleeve it with a piece of steel/copper/w.h.y. pipe and a couple of clips.

Well done on the rest of the job. Sounding good!

[xantia_v6]

The crack in that oil hose is right at the end of the internal steel tee piece, so you cant put an internal joiner there. The existing tee piece has no barbs and is too short for a conventional external clamp. I have successfully fixed one by cutting away some of the plastic outer tee and then binding the hose tightly with steel wire and tying it around the back of the tee to stop it slipping off.

[CitroJim]

Simon, delighted all is now back together and the job was successful Excellent work and well done!

Please get that hydraulic return pipe replaced as soon as you can. I had one of those fail on me and it stranded me. Not long after the same happened to the owner of my original V6...

You'd never believe just how quickly it can drain your LHM reservoir if it lets go. I remember the flat-bed that recovered me being completely soaked in LHM

Get two of them whilst you can so you have one in stock.

The Self-Amalgamating tape may work but I'd be concerned, unless you've proved otherwise, that it may not be very LHM resistant and may dissolve on contact; you'd be amazed at what LHM will eat through given half a chance...

Anything new I plan to use I always test by leaving it sitting in a small jar of LHM for a week or so.

[Mandrake]

Simon, delighted all is now back together and the job was successful Excellent work and well done!

Thanks Jim. Although it was a pig of a job and I would not like to do one again I do feel a sense of satisfaction with the end result. With the extra day to fall back on I was able to take my time and put things back together carefully and fix a few other little issues found along the way such as fixing cable support and routing in a few places, as well as being thorough in my bleeding and testing afterwards.

The temperature gauge performed admirably on this mornings drive - the temperature regulation is a lot better than it has been ever since I've had the car - even before it started sticking shut completely and overheating I think it was partially binding. Instead of moving smoothly to maintain a steady temperature it would stay stuck in place until the temperature was quite a bit too hot or cold then "jump" to a new position when it overcame the friction. So you ended up with the gauge more often than not down at around 70 for long periods (stuck open too much) or between 85-90. (stuck closed too much) Now it doesn't stray far from 80 degrees indicated regardless of driving conditions.

Please get that hydraulic return pipe replaced as soon as you can. I had one of those fail on me and it stranded me. Not long after the same happened to the owner of my original V6...

You'd never believe just how quickly it can drain your LHM reservoir if it lets go. I remember the flat-bed that recovered me being completely soaked in LHM

Get two of them whilst you can so you have one in stock.

At that price I certainly won't be getting two, however yes, given the potential severity of the stranding I think I will fork out for the genuine part. I don't like to fill the coffers of the Citroen parts division but I don't really want to mess around with this kind of LHM leak, or rely on a bodge repair, and the part could go NFP at any time.

Is it fairly straightforward to fit, apart from avoiding siphoning the entire tank out during the changeover ? I didn't look closely but I think the longest piece just connects to a steel pipe near the front of the battery ?

The Self-Amalgamating tape may work but I'd be concerned, unless you've proved otherwise, that it may not be very LHM resistant and may dissolve on contact; you'd be amazed at what LHM will eat through given half a chance...

Anything new I plan to use I always test by leaving it sitting in a small jar of LHM for a week or so.

I doubt that it's oil resistant, and I know from prior experience that after a few weeks of exposure to that level of heat it will go tacky and then hard - it will be impossible to remove it without cutting it off after a few weeks, but no matter if I'm going to replace the pipe anyway.

As I've just spent around £75 on thermostat, gaskets and coolant its going to have to wait for next month though!