KV6 looks like coolant leak - Page 9

TourerSteve · 3rd January 2022, 12:51

Quote:

Originally Posted by kaiser

So I hope you got over the New Year celebrations in good order!

The example I was thinking of was the Merlin engine, of particular interest to us for the above reason, and also that the Meteor (tank version of that engine) was built by ?? - Rover!

Why stop at 2 Cylinders , When you can have 3 cylinders , with 3 crankshafts and 6 piston's

The Napier Deltic was some engine

https://www.youtube.com/watch?v=6NdbonKRyKY

stocktake · 3rd January 2022, 16:35

Have you managed to trace the water leak yet?

Rich in Vancouver · 4th January 2022, 16:49

I posted this after reading the early posts before the thread turned into a contest on unusual engines.

The Keyhole Method!
I have tried that more than once and I don't know if I just don't have enough hand strength or the thermostats on my cars were baked into place but I have had no luck with the Keyhole Method and have always resorted to removing the intakes.
If time is tight it isn't a bad idea to have a pair of intake gaskets on hand just in case you can't work the t-stat free through the keyhole.
BTW: I have had an intake gasket fail on a KV6. It was the only time my trusty FL1 had to be recovered. The leak was from the gasket at the waterway near no5 cylinder. It came out in a fine jet and would empty the coolant tank in less than a km.

BillyMG · 27th March 2022, 12:16

With the sun out I took the opportunity to try and find the leak again. I've added fluorescent dye to the coolant and run the engine with no visible leaks. I also got a pressure test kit and put 15 psi in with no loss of pressure or leaks either. I'm using the glasses and black light to detect any traces of coolant but there aren't any. The trouble is she only leaks when driven hard but she's now sorned and uninsured so I can't take her out for a blast. Any ideas lads??

kaiser · 27th March 2022, 12:42

So, I have not gone back and read the whole thread again.
But, if you have a leak that only occurs when you belt the engine, then it has to do with the pressure in the cylinders.

At full opening and full fuel, your combustion pressure is big enough to escape onto the cooling system and press water out.

Once enough has escaped, the car will overheat.

(this is assuming your fan is working and the radiator is not silted up)

BillyMG · 27th March 2022, 12:50

Thanks for taking the time to read through all that Kaiser! Next question then is what's the answer? New heads? New engine?

xsport · 27th March 2022, 13:36

billly, have you put a large amount of dye in the system that would be easily noticed with your glasses ? i think that if so, once that engine gets really hot and revving highly it still should generate enough heat and pressure for the leak to reveal itself. have another attempt at this and get it very hot at high revs for a sustained period, it might just give you an answer before you start anymore stripping down. it could even be a bad seal on hose clips or anywhere else on a hose for that matter . it must reveal itself somewhere in the cooling system as it is exiting from somewhere, as you can see. the U.V must come out from some point of exit. ....

BillyMG · 27th March 2022, 13:49

Hi Stefan I revved the hell out of her on my drive whilst up on axel stands and got underneath with my glasses and torch. Still nothing!

When she was still on the road I could take her out 30-40mph with no leak but when I took her on the local linkway and gave it some beans I'd get back and find it leaking.

xsport · 27th March 2022, 14:08

if your cooling fan is working and she is topped up correctly, leave her running for a couple of hours and go out after dark. i bet you will get a result. might help the battery get a new lease of life !! that UV should show higher up at some point. not much to lose now billy , you dont want to go down the kaiser route .. not yet anyway ...

SD1too · 27th March 2022, 14:53

Quote:

Originally Posted by BillyMG

With the sun out I took the opportunity to try and find the leak again ... The trouble is she only leaks when driven hard ... Any ideas lads??

Quote:

Originally Posted by BillyMG

... what's the answer? New heads? New engine?

Hi Billy,

In post no. 60 I offered you an idea based on your detection of a smell of petrol in the expansion tank. This was to consider the possibility of an imperfectly sealed inlet manifold gasket where petrol vapour and coolant are separated by a line of elastomer.

In post no. 65 you said that you'd previously fitted new gaskets and tightened up the bolts. Unfortunately that doesn't entirely eliminate the possibility that something didn't go according to plan.

Did you use MG Rover branded gaskets and did you tighten the bolts progressively and evenly and finish with a torque wrench?

Simon

3rd January 2022, 16:35	#82
stocktake Vis Whiz Rover 75 2.5 auto Saloon Join Date: Jun 2007 Location: LEEDS Posts: 20,587 Thanks: 2,057 Thanked 3,056 Times in 1,621 Posts	Have you managed to trace the water leak yet? __________________ Dave... Lost a few stones and a Gall Bladder and part of a bile duct and all of my dignity in the suppository incident

4th January 2022, 16:49	#83
Rich in Vancouver Gets stuck in MG ZT-T Join Date: Jun 2016 Location: White Rock, BC on Canada's Pacific Coast Posts: 849 Thanks: 338 Thanked 367 Times in 210 Posts	I posted this after reading the early posts before the thread turned into a contest on unusual engines. The Keyhole Method! I have tried that more than once and I don't know if I just don't have enough hand strength or the thermostats on my cars were baked into place but I have had no luck with the Keyhole Method and have always resorted to removing the intakes. If time is tight it isn't a bad idea to have a pair of intake gaskets on hand just in case you can't work the t-stat free through the keyhole. BTW: I have had an intake gasket fail on a KV6. It was the only time my trusty FL1 had to be recovered. The leak was from the gasket at the waterway near no5 cylinder. It came out in a fine jet and would empty the coolant tank in less than a km. __________________ ZT-T190, Anthracite, LHD, Left the Line on June 24, 2002, Sold new in Switzerland, spent time in Germany, Imported to Canada in September 2021 Last edited by Rich in Vancouver; 4th January 2022 at 16:58..

27th March 2022, 12:42	#85
kaiser This is my second home 75 Tourer 2.5 Auto, 1.8T, 75V8ZT Join Date: Jun 2007 Location: Johannesburg ZA Posts: 6,200 Thanks: 1 Thanked 859 Times in 613 Posts	So, I have not gone back and read the whole thread again. But, if you have a leak that only occurs when you belt the engine, then it has to do with the pressure in the cylinders. At full opening and full fuel, your combustion pressure is big enough to escape onto the cooling system and press water out. Once enough has escaped, the car will overheat. (this is assuming your fan is working and the radiator is not silted up) __________________ Worth his V8 in gold Last edited by kaiser; 27th March 2022 at 12:45..

27th March 2022, 13:49	#88
BillyMG Gets stuck in MG ZT 2.5 V6 Auto Tourer (Elizabeth) / MG ZT CDTI (Farage) Join Date: Jan 2017 Location: St Helens Posts: 688 Thanks: 339 Thanked 109 Times in 89 Posts	Hi Stefan I revved the hell out of her on my drive whilst up on axel stands and got underneath with my glasses and torch. Still nothing! When she was still on the road I could take her out 30-40mph with no leak but when I took her on the local linkway and gave it some beans I'd get back and find it leaking. Last edited by BillyMG; 27th March 2022 at 13:52..

27th March 2022, 12:16	#84
BillyMG Gets stuck in MG ZT 2.5 V6 Auto Tourer (Elizabeth) / MG ZT CDTI (Farage) Join Date: Jan 2017 Location: St Helens Posts: 688 Thanks: 339 Thanked 109 Times in 89 Posts	With the sun out I took the opportunity to try and find the leak again. I've added fluorescent dye to the coolant and run the engine with no visible leaks. I also got a pressure test kit and put 15 psi in with no loss of pressure or leaks either. I'm using the glasses and black light to detect any traces of coolant but there aren't any. The trouble is she only leaks when driven hard but she's now sorned and uninsured so I can't take her out for a blast. Any ideas lads??

27th March 2022, 12:50	#86
BillyMG Gets stuck in MG ZT 2.5 V6 Auto Tourer (Elizabeth) / MG ZT CDTI (Farage) Join Date: Jan 2017 Location: St Helens Posts: 688 Thanks: 339 Thanked 109 Times in 89 Posts	Thanks for taking the time to read through all that Kaiser! Next question then is what's the answer? New heads? New engine?

27th March 2022, 13:36	#87
xsport Posted a thing or two rover 75 club se Join Date: Apr 2011 Location: Leicester Posts: 1,646 Thanks: 358 Thanked 419 Times in 310 Posts	billly, have you put a large amount of dye in the system that would be easily noticed with your glasses ? i think that if so, once that engine gets really hot and revving highly it still should generate enough heat and pressure for the leak to reveal itself. have another attempt at this and get it very hot at high revs for a sustained period, it might just give you an answer before you start anymore stripping down. it could even be a bad seal on hose clips or anywhere else on a hose for that matter . it must reveal itself somewhere in the cooling system as it is exiting from somewhere, as you can see. the U.V must come out from some point of exit. ....

27th March 2022, 14:08	#89
xsport Posted a thing or two rover 75 club se Join Date: Apr 2011 Location: Leicester Posts: 1,646 Thanks: 358 Thanked 419 Times in 310 Posts	if your cooling fan is working and she is topped up correctly, leave her running for a couple of hours and go out after dark. i bet you will get a result. might help the battery get a new lease of life !! that UV should show higher up at some point. not much to lose now billy , you dont want to go down the kaiser route .. not yet anyway ...