Running out of ideas, Range Rover Classic Cooling issue????

[softdash3.9]

Anyone got any suggestions............

My Range Rover Classic seems to have developed a cooling issue, and I'm running out of ideas!

On start up my RRc heater would start pushing warm air through the heater within @ 1/2 a mile, starting on LPG and warm up normally.

Recently, i.e. now the heater will start to warm, then go chilly cold, LPG vapouriser freezes and have to change to petrol until wamed through again.

Once the engine is up to normal temperature (thermostat open) all functions fine.

There are no leaks, I replaced the 82 deg thermostat (tested it after and was OK) with a 89 degree one.

This happened a few times, so went through the warm up period running on petrol, same thing happened, so this eliminates the LPG side. I also left the heater on cold to minimise the heat being drawn from the system, until warm, this obviously improves things

Wondered if the cooling system had too much pressure as rubber pipes feel as if they have too much pressure, but as stated does not pushed coolant out, I have carefully filled the system, was wondering if it was an air lock or pump cavitation??

Tonight I replaced the 15psi expansion cap, and on the drive home the rubber pipes felt the same, will find out if things are OK in the morning, not too hopefull

Engine runs fine, temperature rises to normal level, does not over heat.

Engine is a late Classic serpentine 3.9, block has top hat liners fitted, I don't believe it is be a head gasket/s, engine was up using all genuine parts, there is no water in the oil or visa versa. I haven't has a sniffer test done though

Any ideas/suggestions, I'm running out of them

[ramon alban]

Hello Royston, the combination of irregular heating effect during warm-up and the fact that the cycle changes when you put the heater on cold (ie a closed water valve - I think?) suggests you a have a combination of two faults.

1) The system is suffering from crud in the gallerries and particularly the Matrix, and as a result

2) it is difficult to purge air from the system because it is more easily trapped

I recommend separating the feed pipes from block to matrix and from block to radiator.

Flush and reverse flush all three sections with a garden hose at domestic water pressure - matrix, block and rad -

Reconnect and fill with water and re-flush/reverse flush all three together.

Leave the water in situ and run up the system.

Use your favourite method to get the air locks out and monitor any changes in behaviour.

Inspect for leaks and do a pressure test to be sure the flushing did not open up any holes.

Testing with water saves losing antifreeze solution if leaks develop.

If/when you have fixed the problem refill with antifreeze at the correct concentration (for Darlington).

If you detect a small/very small leak you can take a punt on Bars Fluid or similar - it works well over the short term, and sometimes a lot longer.

After that, its possible to have partial flow thro a matrix and it may need the caustic soda treatment.

If the problem is not fixed, then suspicion goes to worn impeller blades on the water pump causing seriously impaired flow.

There are three essays on the SD1 system, which may be similar to your V8 that will offer more insight.

http://www.vintagemodelairplane.com/pag ... ant01.html

http://www.vintagemodelairplane.com/pag ... ing01.html

http://www.vintagemodelairplane.com/pag ... emp01.html

[softdash3.9]

Thank you Ramon ,

I will investigate.......

[ChrisJC]

I think you have a failed head gasket - my van did something similar. Once the 'stat is open, then the gases can get out, but until then, they pile up behind the stat until the heater goes cold.

Do a compression test / sniffer test.

Chris.

[gelmonkey]

Royston
If I can add my two peneth worth re the heater matrix and the rad.
I have had a load of these blocked / furred up over the years and have found that this works really well to clean them out.
Get some bi carb and some boiling water.
Mix two tablespoons of bicarb into the boiling water and then carefully pour that into the matrix and leave overnight and then back flush.
The crap that comes out is incredible.
Can do the same with the rad but would suggest that you block off the bottom outlet and fill slowly.
6 spoons of BC should do the job.
Whilst this might not sort your problems it will at least give you good clean units to put back in.

cheers
Paul

[softdash3.9]

I think you have a failed head gasket - my van did something similar. Once the 'stat is open, then the gases can get out, but until then, they pile up behind the stat until the heater goes cold.

Do a compression test / sniffer test.

Chris.

In the back of my mind, that is what I suspect/fear, but push it back out, as i don't really want to strip her down,

Thanks for the suggestions guys , I will work through the list and report back, you need a sanity check every once in a while

We'll see how she goes today

[Jono FD3]

Simple my good man..... you have got an air lock in the coolant system, if the HG had gone you would be loosing water as it would seep in to the cylinders under the intake stroke and you would get condensation coming out the exhaust!!
the only time an LPG system would freeze over would be due to no water circulating through it!! and likewise for the heaters blowing cold air!!

easy way to get around this..... find the highest point in your cooling system (more than likely it will be a pipe to your vaporiser) then follow these steps:

1. pop the pipe off
2. hold it virtical so it is the highest point of your cooling system
3. fill your coolant from the standard fill point
4. once water starts to flow out of the part you removed the pipe push it back on
5. continue to fill coolant to correct level
6. start the engine and let it run with the filler cap off
7. you will see the water level raise & drop (this is normal)
8. once up to running temp, turn off & allow to cool off
9. top up coolant & put the cap back on
10. take for a drive & get it up to temp, then let it cool again
11. top up coolant to correct level, and keep an eye on it over the next few short trips..... after this all should be well

I had the same issue with my opld hilux running LPG, so hopefuly this should sort your issue!!

Jono

[DaveEFI]

On the SD1, it helps on filling to have the car parked facing up a hill - or raise the front - to make sure the filler is the highest point.

[softdash3.9]

Thought I'd better post an update .

I still supect I have a head gasket weeping (money's on the LH one) as there is a small weep of oil oosing out

however still...

There is no water in the oil or visa versa

I have checked the compression, engine was warm and the throttle butterfly was open, repeated the exercise serveral times

Results were

1) 125psi 2) 130psi
3) 125psi 4) 125psi
5) 120psi 6) 125psi
7) 120psi '8) 130psi

pretty even IMO

Engine is @ 9.5:1 CR

The 89 deg thermostat since fitting appears to have made things a little worse.

I haven't had chance to flush the heater matrix/or radiator but I have checked that there ae no blockages with no apparent restrictions.


I have continually monitored coolant level, it remains pretty constant, until the system pushes coolant up into the expansion bottle and through the cap relief (new cap) this only occurs when the engine has warmed through and allowed to cool (but not overnight) but not every time.

One observation I have made is that when the heater/vapouriser is chilling, if I keep the revs above 2000 rpp (2250-2500 ish) the system purge itself and heat is returned. If the emgine is not fully up to temperature and engine revs are low, heater will chill.

If I keep the revs higher (as above) the heater works normally as is warms, until the thermostat opens, and it will chill for a while
Once the engine is up to temperature and the thermostat is fully open it runs with no problems.

Been using her all over Christmas

It is obviously developing an air lock, but do not believe it is from filling the system.

Could possibly be an issue with the water pump, but just monitoring things to see if I can ascertain/prove it is a head gasket, and I'll fix it.

Not wanting to strip her down replace the gasket and find it is not the issue.

Your thought and theories welcome

I will have to get a sniffer test done really!!

Hope you have all had a great Christmas and hope you have a happy new year!!

[ramon alban]

Happy New Year Royston, Just when you think its gonna be a good year then - Oops - more cooling probs.

If you do have a minor head gasket leak is it possible for you to work around it for the time being by fitting a fairly large overflow bottle nearby, but below the pressure cap? Say, a flat plastic shampoo bottle about 1 liter clamped to the inner wing or chassis rail.

Then route the overflow pipe that normally deposits fluid to the road into the bottle.

Clearly you system must be pressurizing for it to push fluid out, so when it cools the resulting vacuum will suck back the "lost" fluid.

It worked fine for several years on my VDP SD1.

Indeed, a treatment of Bars Fluid also helped to stop it getting worse.

As a bonus, if you pre-fill the overflow bottle with coolant and, perchance the minor leak is persisting, from another unseen location (eg matrix or a water jacket pinhole) then the sucking function (do not spoonerize) also acts as an automatic top-up process , which is dead easy to refill the otherwise lidless bottle, even carrying a spare gallon of coolant in the boot for emergencies - as it were!

[softdash3.9]

I have been thinking about an over flow tank, Ramon, I haven't got anything devised yet, unfortunately the RRC dumps it straight out of the cap and not down an overflow pipe a la SD1

But I do have a spare SD1 coolant tank somewhere and I'm working on it


Forgot to mention also all the plugs are all an even colour

[softdash3.9]

Well having limped through the winter, I came to the conclusion there is a HG leak from No 1 cylinder into the water gallery, found a discoloured No 1 plug.

I have kept her as a spare car incase the weather turned nasty


Finally took the plunge today and started to strip the Inlet manifold and then tomorrow should finishe LH head off for inspection.....




.....watch this space for an update soon

[bodger]

78 degree stat works best

[softdash3.9]

78 degree stat works best

Was definitely better with the 82 deg rather than the 89 deg

[softdash3.9]

Well here's the damage
Head gasket failure on No 1

and No 5


Block face and head luckily are not damaged
No 1

No 5


Wasn't expecting it to be that bad, but at least no machining is required. I have carefully cleaned all the residue off the block/head and there is no localised pitting, Phew!!

This is the bank that the engine builder incorrectly installed the conrods in the wrong way round and they ended up stripping this side to fix. I found some on the inlet manifold bolts finger tight (yes I mean finger tight) and the head bolts didn't appear to have has much "stretch" when slackened.

Gaskets/bolts ordered next week