75ZT Community

Michael Bee · Posted 17 Jan 2012, 11:41 #1

Just bought a 75 connie CDT in December - I have been doing all the usual servicing myself, until last week I started losing coolant by the bucket load, then I went to change the PCV (Positive Crankcase Ventilation Valve) filter and found it clogged with mayo.

I know the first thing everybody will say is Head Gasket Failure, but the oil looks fine and I am not getting any oil in the remainder of the coolant. The car is running fine at the moment (I just keep refilling the coolant to keep it running).

I phoned a Rover specialist in Sheffield and they said HGF (Head Gasket Failure) over the phone - does anybody have any other ideas or solutions?

Thanks in anticipation :-)

Mick · Posted 17 Jan 2012, 12:12 #2

Never heard of HGF on a diesel.

I suppose it's possible.
As an example of what can occur, my next door neighbour with a TF was losing coolant, this did not show at all when stationary, the system had to be under normal driving condition pressure for it to occur. Turned out to be a pin hole in one of the coolant pipes running from front to back, took weeks for the garage to locate the problem.
Not any help I know, just an observation. Hope they can locate the problem PDQ.

Duncan · Posted 17 Jan 2012, 12:12 #3

Is there mayo under the oil filler too? To get into the PCV, I would think it has to be coming from the bottom end of the engine. You don't always get oil in the coolant if the coolant is leaking somewhere the oil isn't pressurised.

Unfortunately I don't know the engine well enough to be certain, but there aren't many other possibilities I can think of.

PaulT · Posted 17 Jan 2012, 12:15 #4

You can buy units that fit on to the filler cap so as to pressurise the cooling system to help find leaks etc

Michael Bee · Posted 17 Jan 2012, 12:23 #5

Duncan wrote:Is there mayo under the oil filler too? To get into the PCV, I would think it has to be coming from the bottom end of the engine. You don't always get oil in the coolant if the coolant is leaking somewhere the oil isn't pressurised.

Unfortunately I don't know the engine well enough to be certain, but there aren't many other possibilities I can think of.

There is a slight bit of mayo under the oil filler cap - not much. The PCV was like a party size jar of Hellmans.

Michael Bee · Posted 17 Jan 2012, 12:35 #6

Does anybody know where the coolant runs through the engine block? (all the diagrams that I have seen show it going in and coming out but not where it goes)

takestock · Posted 17 Jan 2012, 13:16 #7

Isn't usually an oil cooler failure that causes these symptoms on the diesel

Duncan · Posted 17 Jan 2012, 14:20 #8

takestock wrote:Isn't usually an oil cooler failure that causes these symptoms on the diesel

It certainly could. It's an oil to water oil cooler if I remember (just by the oil filter?) so a good chance you are right.

Michael Bee · Posted 17 Jan 2012, 15:06 #9

Duncan wrote:
takestock wrote:Isn't usually an oil cooler failure that causes these symptoms on the diesel

It certainly could. It's an oil to water oil cooler if I remember (just by the oil filter?) so a good chance you are right.

Sounds feasible, but I would have thought the evidence would be all over the engine, in the oil, out the dipstick not just clogging up the PCV. I am talking about losing litres of coolant every few days.

takestock · Posted 17 Jan 2012, 15:28 #10

Well, I am a 2.5 kv6 man but I an almost certain that there has never been a reported HGF failure on the diesel engine used in the 75. In the cases I have read about oil and water mixing on the diesel, the culprit has usually been the oil cooler. Could another culprit could be the inlet manifold/gasket?

Michael Bee · Posted 17 Jan 2012, 15:42 #11

takestock wrote:Well, I am a 2.5 kv6 man but I an almost certain that there has never been a reported HGF failure on the diesel engine used in the 75. In the cases I have read about oil and water mixing on the diesel, the culprit has usually been the oil cooler. Could another culprit could be the inlet manifold/gasket?

Yes, I wondered why there are head gasket kits for the petrols all over the internet, but the kits for the diesels are a really rare find.

Really appreciate the ideas - just don't want the garage to blindly reach for the HGF explanation when I take it in.

takestock · Posted 17 Jan 2012, 16:52 #12

I think regardless of the actual cause, if the garage in this situation and this engines reputation go for the HGF with no real investigation, you should find another garage

Duncan · Posted 17 Jan 2012, 20:13 #13

Just looked at the workshop manual for the engine, and it doesn't seem to have any water in the manifold. As it's a turbo engine and the manifold is plastic that doesn't really surprise me, because the air will be heated anyway by the turbo compressing it, and the manifold will get warm quickly.

The coolant loss could be a hidden pipe somewhere, but it seems inconsistent with mayo in the PCV and filler cap that I've never heard of before.

Dave's suggestion of the oil cooler is the one that seems most sensible, and maybe there's no oil in the water because when running, both the oil and water are pressurised, whereas with a hot engine the water pressure will remain for quite a while when the oil pressure drops off.

James.uk · Posted 19 Jan 2012, 03:52 #14

I think you are looking at two entirely diff issues here. The gunged up PCV is perfectly normal over a period of time, just change it before it causes turbo failure.
As for the vanishing coolant, that should be easy to find, if it isn't leaking externally, then Dave's probably right. But with the amount you seem to be losing your sump should be overflowing! lol.. :shrug:
I think you have a porous pipe somewhere that only leaks under pressure.. ..
One thing I am certain of, is that your head gasket is fine..

Again Dave is right, go to a better garage..

...

Duncan · Posted 19 Jan 2012, 07:59 #15

Gunged up PCV, yes. Gunged up with Mayo, no. It's normally gunged up with black stuff.

Bermudan 75 · Posted 19 Jan 2012, 08:56 #16

If the loss of coolant and gunged up PCV are two seperate issues thenthe loss of coolant may be from a split in a coolant pipe that only opens whilst the engine is running.

Many years ago my Triumph Spitfire IV was losing coolant. I could not find the source of the leak until I checked the bottom radiator hose with the engine running.

The movement of the engine was causing a small split in the bottom radiator hose to open up, when the engine stopped running the split did not lose coolant.

Could the same thing be happening with Michael's car I wonder?

Michael Bee · Posted 19 Jan 2012, 09:26 #17

Update:

Yesterday I had problems starting the car after I had just nipped into the shops. Checked the coolant, it had stopped disappearing but the oil had turned chocolate milkshake brown.

I kept my appointment with the garage this morning (thankfully it started ok and ran perfectly fine to get me there) - the guy in there said that he had only ever fitted a HG to a diesel 10 years ago on an engine where the factory had not seated the head properly. Looks like the rush to make a judgement was made by the person answering the phone, not the mechanic himself.

The garage are going to pressure test the engine this morning and let me know this afternoon.

Just to keep him on his toes, I mentioned that this forum is eagerly awaiting the diagnostics.

Let you all know later.

PS. thanks for all the support.

Michael Bee · Posted 20 Jan 2012, 09:28 #18

Oh dear! The pressure test did in fact reveal a HGF. A bill for around about Ã‚Â£1000, so it is uneconomical to get it fixed.

I have decided to break the car myself as there are alot of nice bits on it being a Highline model - I think I will be able to recover more of what I paid for car that way.

Bermudan 75 · Posted 20 Jan 2012, 09:42 #19

Before you start breaking the car, hang around the forum, someone might know where you can get the repair done for less than the garage quoted. Garage might have quoted the high figure because they don't really want the work. Shame to break a Connie SE.

Duncan · Posted 20 Jan 2012, 09:51 #20

It does sound very steep for a head gasket. It's only Ã‚Â£500 for the K series and that's a more invoved job as far as I know. Ã‚Â£1000 for a KV6 I could see.

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Losing Coolant and my PCV is clogged with mayo by Michael Bee (Page 1 of 2)