Think I know why this tidy old car was scrapped.

Think I know why this tidy old car was scrapped.

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MGJohn

Original Poster:

10,203 posts

183 months

Friday 18th July 2014
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03-Reg Rover 75 1.8 Turbocharged Petrol.

Saw this car soon after it had arrived a couple of weeks ago. It had the PRT ( Pressure Relief Thermostat ) and as I needed that assembly for my ZT 1.8t which does not have it...... Whilst removing that I checked the condition of the Turbocharger and there was little play in the turbine shaft either end so decided to have that too. I do not think the Turbocharger was the original judging by its appearance and the fact that the Exhaust Manifold to Turbocharger Flange mounting nuts and studs were not the originals. In fact a bolt was used and all the nuts were poor quality hex-nuts ( six flats ), not the better quality original bi-hex original fitments.

As on the previous visit I had removed so much stuff, Cylinder Head removal on this car would not take long so I returned this afternoon. I do not think this Cylinder Head had been removed since the car left the factory. Several signs confirming this. Soon had it removed.





The coolant pipe PEP 102160 which runs behind and around the engine and over the bellhousing was obviously new and fitted recently.





The Thermostat housing contained a new Thermostat ... the car had a PRT fitted ... Hmmm.



PEP 102160 should be secured with two 10mm Bolts. It has two strong brackets for the purpose. Only one contained a Bolt! At least one of the 13mm Nuts securing the plastic Inlet Manifold to the Cylinder Head was missing. Several were only finger tight. Most of these are difficult to access and the one missing was the most difficult to access. Also, only one was the better quality original nut the car would have left the production line with.

Removal of the Inlet Manifold would be the best way to fit that new Coolant Pipe.

So, based on these observations, whoever fitted that new coolant pipe, be they amateur or pro were lazy or not very thorough. Maybe both.

Discussion: The car showed no signs of cylinder head gasket damage but, surely TWO Thermostats would lead to overheating and that I feel is the reason this half decent, relatively low mileage car met a premature end.

The latest and current MoT ( Expires Oct. 2014 ) was present in the car which I used to check the MoT history on VOSA. No worries there.

Closer inspection of the Cylinder Head showed it has never been skimmed. Bonus. I'd bet it has not been off the engine since the car left the production line based on my checks. Delighted with it.

Nealio

307 posts

193 months

Monday 11th August 2014
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If you believe the car may have overheated due to the thermostat setup, doesn't that make that nice head slightly suspect?

MGJohn

Original Poster:

10,203 posts

183 months

Monday 11th August 2014
quotequote all
Nealio said:
If you believe the car may have overheated due to the thermostat setup, doesn't that make that nice head slightly suspect?
This is a frequent when folks entrust their cars to garages for a simple task of say fitting a new coolant rail pipe in place of a corroded one. See new one in picture, they not knowing of the PRT ( Pressure Remote Thermostat ) fitted to some of these cars, so fit a new Thermostat in the usual place. Apparently some cars run OK with TWO thermostats whilst others show signs of overheating. Probably depends on the use cars are subjected to.

Yes, possibly I did think of that 'suspect' angle. Having inspected it after a thorough clean up including a light machine surface grind to remove any imperfections, I'm delighted with it. Signs were that Cylinder Head had never been off the car since it left the production lines at Longbridge. Car less than 80,000 miles. Current MoT Certificate still in the car. The engineering firm I took it to with a wide experience of these things agree. No sign of previous skim.

Corroded coolant pipe allows coolant to escape so leaking cooling system never reaches normal operating pressure essential in a healthy engine. That leads to premature boiling and overheating as system never reaches normal operating pressure. Leaky pipe identified and renewed. Better fit a new Thermostat in the empty housing whilst at it ..... Job done.

If only life was as simple as that. Sod's Law often has the final say ... smile

LeoZwalf

2,802 posts

230 months

Saturday 29th November 2014
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Hi John - you may remember me from Rovertech smile
Always enjoy your posts, very informative and you have such a unique style I can usually tell it's you before seeing your username thumbup

Can you tell a little about the PRT? I've never heard of that before.

Cheers,
Leo

MGJohn

Original Poster:

10,203 posts

183 months

Saturday 29th November 2014
quotequote all
LeoZwalf said:
Hi John - you may remember me from Rovertech smile
Always enjoy your posts, very informative and you have such a unique style I can usually tell it's you before seeing your username thumbup

Can you tell a little about the PRT? I've never heard of that before.

Cheers,
Leo
Hi Leo,

Haha!

In a nutshell, it's a simple case that TWO thermostats are rarely if ever better than one... wink

There has been a number of instances where folks have found TWO thermostats fitted to their cars' engines.

If you read up on the PRT, you will have a better concept of how that works and is generally regarded as superior to the normal set-up in most respects. Many believe it goes along way to protecting the K-Series from overheating issues and other heat related problems such as cold shock leading to engine damage. The first thing damaged when an engine overheats is usually ... wink

I have two MG ZT 1.8Ts. One is fitted with the PRT the other has the Thermostat located in the usual K-Series location next to the Water Pump. I am in the process of removing the conventionally located Thermostat from one of the cars and fitting the PRT set up as based on my experiences so far with these cars, the PRT set-up is the better option.