KV6: The Coolant Chronicles.

GadgetBoy · Post by **GadgetBoy** » Thu Jun 16, 2011 7:54 pm

In order to try and find a persistent coolant leak I've done a lot of work on my car recently including:

Thermostat and associated pipes replaced
Inlet manifold gaskets replaced
Inlet chamber seals and o-rings (nothing to do with coolant but I was there)
Water pump replaced
Timing belts and associated twiddly things (again not coolant related but I was there)
New plugs (those back 3 are a lot easier with all the gubbins out of the road)
All coolant plumbing/hoses have been checked
New expansion tank cap
Heater matrix inspected
Radiator inspected

As a result I've found out I have a factory replacement engine and some buggr's had me oil cooler!

With all the work done the engine is running beautifully. Smoother, more responsive, noticeably more get up and go and improved fuel consumption. You would think it has just left the production line.

And .........

STILL losing coolant!

Not a lot but a measureable amount every day. The following table/chart details:

As you can see the mileage has little relationship to the amount of coolant lost. My driving style has been consistent. It would appear the coolant loss is random but I'm convinced more is lost when the A/C is on (clue?).

I do, however, now know where the coolant is going ....... into the oil.

There is absolutely no evidence of head gasket(s) failure so I have come to the sad conclusion I have a liner problem.

I have the advantage of a second car (needs MOT'd but that ain't a problem) and I've sourced a short block for very little money. So, before I whip the engine out has anyone got any bright ideas?

excossack · Post by **excossack** » Thu Jun 16, 2011 8:22 pm

Do you have an oil cooler?
Is it part of the rad? If so, could the rad be leaking into the oil cooler and into the engine.....

A long shot.....but...?

GadgetBoy · Post by **GadgetBoy** » Thu Jun 16, 2011 8:29 pm

The oil cooler has been removed.

excossack · Post by **excossack** » Thu Jun 16, 2011 8:30 pm

Ive just found your post on www.the75andztclub.co.uk/

Worth a try...

mooshaker · Post by **mooshaker** » Thu Jun 16, 2011 10:20 pm

dunno if you know Rover had an issue with porose castings with everything from blocks..heads...manifolds the lot also the machine faces never ran flat ..drilled holes went to deep into water jackets ....blame Paymaster General Geoffrey Robinson skimmed off the workers pensions so noone gave a monkeys and built rubbish basicaly ...i lost my job as a result of his skimming .....just a thought that was all

GadgetBoy · Post by **GadgetBoy** » Fri Jun 17, 2011 7:20 am

I'm fully aware of Rover's history and the problems they had. My car is a 2002 car when Rover were just about as healthy as they ever were.

Time will tell where the problem really is when I strip the engine but I'm pretty certain it's a liner issue. While not a common problem it is a known issue with the KV6.

Apart from the engine issue it's a beautiful car. Absolute top of the range with pretty much every option there is. It drives beautifully and wafts along with the sort of ride you would normally expect from a Bentley. The V6 is an absolute peach of an engine. Never fails to turn heads when I give it the loud pedal and will still pootle around when I'm in pipe and slippers mode.

Neil Chowney · Post by **Neil Chowney** » Fri Jun 17, 2011 1:22 pm

Gadgy, Does it lose colant when stood still?

If it is doing it under pressure/ running conditions there MIGHT be an issue if there are studs that protrode into the water jacket (manifold ect) that also breach the oilways or the sump / crankcase.

Total shot in the dark bu the FIAT TC lump looses oil from the cambox via the studs if not correctly built.

GadgetBoy · Post by **GadgetBoy** » Fri Jun 17, 2011 1:44 pm

Only when running Neil.

mooshaker · Post by **mooshaker** » Fri Jun 17, 2011 3:30 pm

2000 to 2001 all the fubard parts were cast and machined and sent to rover/ford/jaguar/smart as thats when we found out about our pensions if the fault is say a tap hole/crack/porose into the exhaust or inlet ways you will never find it ....i have in the past to find leaks put ribena in the water system then park it over some white paper towel just to get a rough idea even if you cant see any drips on the engine the paper will show where to look up at then follow where you think the route it may of taken as leaks rarley just come down

GadgetBoy · Post by **GadgetBoy** » Fri Jun 17, 2011 7:10 pm

Drip test already done. Guess what ..................... no drips!

mooshaker · Post by **mooshaker** » Fri Jun 17, 2011 7:25 pm

do they have sleeves on that engine ? sometimes they lift the width of the head gasket ......you can sometimes fill with neat antifreeze as that is a crack/hole finder and follow the smell ish ?? just bunging some ideas in ..

GadgetBoy · Post by **GadgetBoy** » Fri Jun 17, 2011 7:32 pm

Liners you mean?

Yes. If you read the first post you'll see the problem has already been diagnosed as a liner issue.

mooshaker · Post by **mooshaker** » Fri Jun 17, 2011 7:43 pm

have you had the heads off ..if you put extra anti freeze in take a plug out at a time then run see which steams or smells save taking both heads off just to tap a sleave back down ..good luck anyhow ..that and the honda v6 are top engines think they use them in the stratos kit cars

GadgetBoy · Post by **GadgetBoy** » Fri Jun 17, 2011 7:50 pm

The liners go in from the crank end and are shouldered. They're glued in with Hylomar and if there hasn't been enough applied they can slip down.

I'm going to try Steel Seal in it because a number of KV6 engine owners have had the same problem and Steel Seal has sorted it. Normally I'd boil anyone who uses Steel Seal (or K-Seal) in oil but I've got nothing to lose. As it stands at the moment it's fecked.

It's Steel Seal or a rebuild.

excossack · Post by **excossack** » Fri Jun 17, 2011 8:23 pm

Would it be worth pressure checking each cylinder or doing a head sniff?
What makes you so sure its not the head(s)?