Thread: Cooling System - 1980 3.5lt Range Rover

G`day Mark ,

Don`t know really , may sound silly but there are some things that are worth taking note of when everythings working as it should and i know these are the times that normal types don`t .

I can`t put it into an understandable quantity because if usuals not known ?

Lpg seems to give off more than petrol but in fumes mostly some but not alot of liquid and it`s dependant on the outside air temp .

I guess a stroked 3.5 is more prone to slip a liner because of the extra stroke or use of more of the length liner and also being 030 over for 4.3 .

3.5s if bored seem to be more prone to liner shift than std bore 3.5s but std ones that have been hot will shift also .

The thing about these engines is it doesn`t affect the block .

The liners can bang and rattle because it can move up and down but they don`t suffer like the 94mm bore engines because they have more than twice the amount of alloy surrounding the liner in some cases .

Liner shift , that is making a noise in a std or oversize 3.5 is not as sever as liner shift in a stroker because of the stroke . The std 3.5 has more room for error because of the crank weights .

It does depend which 3.5 also because some are stronger than others .

Most shifted liners i`ve seen in 3.5s have settled downward and if the case it is often possible to fit a 94mm oil ring side rail , which takes up the space and stops the movement . Probably not the best fix but short term and cheap .

So if you have an over heating/coolant problem unless your very unlucky it`s not liner shift .

Cheers

Most of this will be signatured

ADD ............... i forgot to say that i have an 030 3.5 in the shed was in the RR once it has 8 dropped liners , it had been hot on a couple of occassions .

It had no liner noise when running ever , even when over heated , it also never had any problem with coolant because of the liner shift .

It got hot enough to break rings but it ran for about 3 mths on those broken rings and still made no liner noise .

To break rings they have to get fairly warm .

Thanks for the great reply Peter R

There is a noticable amount of water vapour coming out of the exhaust when the car is started. This does go away once you rev it a bit, but seems to be more then there should be (droplets of water form in the tail pipe). Haven't had a good test of this yet, so could just be when on LPG.

Good point about the fans and electrical load. I know with my current thermo's they are running most of the time (as far as I know). I like the idea of having the light to show when they are operating. Is this as simple as running another cable off the 87 prong on the relay?

I am thinking of trying the following:
1) Setup the AU fans.
2) Remove the gas system, eliminating any possible air leaks from the convertor or hosing.
3) Have radiator rodded and re-tested.

Is it worth trying any of the radiator stop leak products to try and seal up any cracks/leaks??

Cheers,

Luke

Originally Posted by LukeV

Thanks for the great reply Peter R

There is a noticable amount of water vapour coming out of the exhaust when the car is started. This does go away once you rev it a bit, but seems to be more then there should be (droplets of water form in the tail pipe). Haven't had a good test of this yet, so could just be when on LPG.

Good point about the fans and electrical load. I know with my current thermo's they are running most of the time (as far as I know). I like the idea of having the light to show when they are operating. Is this as simple as running another cable off the 87 prong on the relay?

I am thinking of trying the following:
1) Setup the AU fans.
2) Remove the gas system, eliminating any possible air leaks from the convertor or hosing.
3) Have radiator rodded and re-tested.

Is it worth trying any of the radiator stop leak products to try and seal up any cracks/leaks??

Cheers,

Luke

Hi Luke ,

I wouldn`t take too much notice of the fluid from the tailpipe unless you have a measure .

It`s like when there is an overheating problem , it`s one of the few times the bonnet gets lifted when everything`s hot and unless you have a measure they can seem very hot but the thing is they are very hot when the bonnet is opened even when the gauge is reading in the right place .

Another one of those things to do when everything is working as it should be .

Yes all 3 sound good to me though i`d probably do it in the reverse order and if you haven`t , put a new thermostat in at the same time .

If you rod the rad fit a stat and you`ve already done the gaskets , that`s 3 eliminations which you know are good .

If the Radiator hasn`t been rodded in the last 2 yrs , could be that it is the culprit and always a good idea to look at when any overheating problem . If it`s not allowing the coolant to flow at the right speed through the engine it will act as yours .

The current fans should only run either when the AC is on or when the engine is hot as in above normal running temperature .

It`s possible the fact that they are running they are trying to tell you something .

It may be worth taking note of what they are doing and when .

If not an electrical problem it may be air in the system is making steam ( sort of ) in the manifold which is causing the fans to initiate .

If it was from overheating without air in it i`d expect the gauge to be reading very high .

If the problem occurs at highway speeds the AU fans won`t alter much as far as the gauge goes , they will run all the time and this will limit their useful life span .
The AU fans will only do very much at idle and slow speeds also when slowing for towns , to 50/60 kph they will come on , short term .
In general any speed above around 70 kph will have no need for the AU fans , unless a very hot day and the thermastatic switch is set fairly low .

With the light i used a sole twin fused relay but yes i only ran an extra wire into the cabin , it could be inline but if it fails so will the fans .

I`ve heard of 3 people using chemiweld with good results but follow instructions , if after the radiator is rodded and the problem persists , i`d think about using it . I would only use it if everything else checked out ok and a block crack was a big possibility or if an engine had been overheated as a safe guard .

Only thing is that when used the LPG coolant ports need to be bypassed because the converter relies on heat dissipation and any of the gunk used can upset how the coolant works inside the converter , this also applies when any cleaners are put through the coolant system .

Cheers

Peter

Is it worth trying any of the radiator stop leak products to try and seal up any cracks/leaks??

Only if you're desperate. Some of them can work but can also gunk things up a bit.