P38 2001 Plate 4.0 V8 Overheating

[teessidelad25]

Hello All been a long time since i was on here thank good no problems but no i got what i think is one thats gonna cost some nmoney.

Started a few weeks back when i was was topping up the radiator expansion tank every other week and now the car red light on the dash comes on after only trravelling about 5 or 6 miles and when you stop engine red hot and undo the tank cap and steam all over so im guessing it defo is overheating.

I've tried changing the thermostat which was a bit of a nightmare lol but still the same. Any Ideas ??????????

another issue thats started recently is i've got no control over the electric fans in the cabin seem to be on full blow all the time .. ~Any ideas ???

all help appreciated

[MrDiagnostic]

I would start by flushing the radiator mate,as its quite common for them to block also check you are getting a return flow from the thin plasic tube to the header tank,these can block...

[teessidelad25]

I would start by flushing the radiator mate,as its quite common for them to block also check you are getting a return flow from the thin plasic tube to the header tank,these can block...

Seems to be pressure and pipe getting hot and seems to be a bit of flow.

Some more info after investigations last night

car was left overnight then started her up took cap of expansion tank then reved her a bit nothing felt pipes to see if they where getting hot and not a lot after about 6-7 mins idling the pipes started getting hot but no pressure in them. I then started tio rev the engine to about 3.5k revs and after aboput 30 secs the hoses started to pressure and the expansion tank bubbling then when i stop reving the pressure goes after about 30 secs of idling. ???????????

with regards to wet passenger footwell mine seems to only do that when i have the aircon turned On if aircon is off there doesnt appear to be any water.??????

[q-rover]

Wet footwell, if it isn't the heatercore or the O-rings, which by the sound of it, it isn't

then check the AC drainage tubes that exit the floor either side of the gearbox.

You'll need to crawl under with a torch and a long pokeything.

[Hybrid_From_Hell]

Amazed nobody has said it yet, but there are only a few things this can be

1st Route : Blocked rad / cooling system / Thermostat... being one route multiple possibilities

2nd Route : Blown head gasket(s)

3rd - pray not - cracked casting behind liner (not the same as liner slip)

4th - pray again : Liner slip

The 4.0 engine is more prone to casting cracks behind the liner, these blocks were made of grade 2 or 3

blocks - whereas the 4.6s where made from grade 1 block due to the thickness needed when line bored

for the liners, the 4.0 blocks where therefore "lower quality" castings tolerance wise for thicknesses

for what would be the liners and the metal thickness behind them, some call this "porus" blocks not a true description

the 4.0 also were made to run hotter , and have a werid heating up can run hot / process that long terms many engines don't like

and makes them run hot, this in turn can cause cracking of the very thin ali between the water jacket and liner

with the result of 1000 PSI coming upwards into the water system

Take out the spark plugs, does one look steam cleaned ?

Get a Test done on the water to check for gases present when hot, if positive then its head gasket or cracked block / liner probs

Nige

[Ally V8]

Amazed nobody has said it yet, but there are only a few things this can be

1st Route : Blocked rad / cooling system / Thermostat... being one route multiple possibilities

2nd Route : Blown head gasket(s)

3rd - pray not - cracked casting behind liner (not the same as liner slip)

4th - pray again : Liner slip

The 4.0 engine is more prone to casting cracks behind the liner, these blocks were made of grade 2 or 3

blocks - whereas the 4.6s where made from grade 1 block due to the thickness needed when line bored

for the liners, the 4.0 blocks where therefore "lower quality" castings tolerance wise for thicknesses

for what would be the liners and the metal thickness behind them, some call this "porus" blocks not a true description

the 4.0 also were made to run hotter , and have a werid heating up can run hot / process that long terms many engines don't like

and makes them run hot, this in turn can cause cracking of the very thin ali between the water jacket and liner

with the result of 1000 PSI coming upwards into the water system

Take out the spark plugs, does one look steam cleaned ?

Get a Test done on the water to check for gases present when hot, if positive then its head gasket or cracked block / liner probs

Nige

Fridge,I dont quite get what you are saying - the 4.0 and 4.6 are all 94 mm bore the stroke is longer on the 4.6 thats all.

[Hybrid_From_Hell]

Fridge,I dont quite get what you are saying - the 4.0 and 4.6 are all 94 mm bore the stroke is longer on the 4.6 thats all.

Its not Fridge its ME

Yes the bore is the same on 4.0 and 4.6s

BUT

On the factory castings the casting vary with cast tolerances, thus they measured the ali thickness between the water jacket and the liner surfaces, and graded them into 3 grades say 1 2 and 3 (they were red yellow and blue, I think red best blue worst), these have a dab of paint on the valley area, often has gone when looked for, but the importnant thing is that ALL 4.6s are made from reds and a few from yellows when they were desperate, and ALL 4.0s were made from yellows and Blues when desperate, but NO 4.6s made from blues.

Thus the Blues have the highest chance of the ali behinds the liner cracking, and the probs, as the ali is the thinnest of all the grades, the 4.6s are of better blocks, so the ali often doesn't crack but the liner moves.

Hope that makes better sense, its one of those areas that a little info can not sometimes make sense - esp from moi

Nige

PS

Being seriously sad I have the block tolerance specs saved somewhere,

But.... in the interests of me needing to get out more, getting a life and not making members

keel over with stunned bordom I'll stop now

....that is unless theres another V8 petrol sadhead like me who would like this excriutingly dull info

[BogMonster]

Is that the rustle of an anorak I hear?

[teessidelad25]

Hello All

thanks for the posts I've had a garage from Thirsk come up to see me in Stockton On Tees and theve confirmed its a Blown Head Gasket Bummer.

He quoted me £380 just for Labour & skimming heads. Parts extra or i could supply them for him he said. Anyone think this a good price and where i can get parts from ??????

As with regards the Wet footwell he thinks its the heater Matrix.

[Hybrid_From_Hell]

If its a head gasket then thats good news

However, its not tricky, its just nuts and bolts and why does he think the heads have to be skimmed

without checking them 1st, or even seeing if they have been done 47 times previoulsy ?

Using Composite head gaskets and a socket set and a ferw simple cheap tools,

this is doable yourself, the only tricky bit would be a torque wrench for the head bolts,

Consider doing it yourself, either way pray this does the jobbie, what has made him so certain its the head gaskets ?

Did he do tests or was it the "finger in the air and here's a quote" method ?

Nige

[teessidelad25]

If its a head gasket then thats good news

However, its not tricky, its just nuts and bolts and why does he think the heads have to be skimmed

without checking them 1st, or even seeing if they have been done 47 times previoulsy ?

Using Composite head gaskets and a socket set and a ferw simple cheap tools,

this is doable yourself, the only tricky bit would be a torque wrench for the head bolts,

Consider doing it yourself, either way pray this does the jobbie, what has made him so certain its the head gaskets ?

Did he do tests or was it the "finger in the air and here's a quote" method ?

Nige

He just did same tests as me by revving engine with the expansion cap off and the water bubbles up when reving and pressure only there when revving. also seems to be drinking water like no ones business drinks a tank overnight and no water on floor god knows where its going, not in the oil thou ???

He said he always skimms regardless and its only 70quid and he pressure tests them.

I was tempted to do it myself and i do have most of the tools required including torque wrench, how long do you think it would take me, also been looking in the manual about timing chain and recommends changing at 100k and mines done 110k.

Price any good ???????

[Hybrid_From_Hell]

What he has done will not for sure prove its a head gasket.

What you need to see is the piston crown - ie the head off, and maybe a compression test would have helped

You have pressurization of the system, it could be the Head Gaskets, but equally you may pay out £400 + + and find it no

better. I would have expected far more disgnostic than a good rev of the engine and "Its yer head gaskets guv innit"

Again why does he think the head will definately need skimming before its even apart ?,

Nige

[teessidelad25]

What he has done will not for sure prove its a head gasket.

What you need to see is the piston crown - ie the head off, and maybe a compression test would have helped

You have pressurization of the system, it could be the Head Gaskets, but equally you may pay out £400 + + and find it no

better. I would have expected far more disgnostic than a good rev of the engine and "Its yer head gaskets guv innit"

Again why does he think the head will definately need skimming before its even apart ?,

Nige

He told me that past experience tells him it will need skimming as he has done heads before and not skimmed and had problems so now he wont touch without skimming.

what other tests can be done ?? any i can do ???

[Hybrid_From_Hell]

He told me that past experience tells him it will need skimming as he has done heads before and not skimmed and had problems so now he wont touch without skimming.

what other tests can be done ?? any i can do ???

You could do a compression test on all 8 cylinders when cold, if the compressions are all good then its more unliklely not to be a head gasket.

Go for a run, when it gets really hot push the clutch in / into neutral, ignition off, and coast to stop, then remove all the spark plugs, they SHOULD all be the same colour, if one looks steam cleaned then thats the cylinder at issue, the more steam cleaned it is the less likley its a head gasket

But, the best check is to remove the cylinders heads and check the vlave area and piston crowns

Head gaskets do fail, and I have replaced many without having to skimm them, yes some do need it, but not always, need to check the heads to see if they can be skimmed (if done before oo many times there is a limit) and even if they need skimming.

All in all I am unconvinced with the diagnosis, if it is right and everything is done properly price is OK

Nige

[teessidelad25]

You could do a compression test on all 8 cylinders when cold, if the compressions are all good then its more unliklely not to be a head gasket.

Go for a run, when it gets really hot push the clutch in / into neutral, ignition off, and coast to stop, then remove all the spark plugs, they SHOULD all be the same colour, if one looks steam cleaned then thats the cylinder at issue, the more steam cleaned it is the less likley its a head gasket

But, the best check is to remove the cylinders heads and check the vlave area and piston crowns

Head gaskets do fail, and I have replaced many without having to skimm them, yes some do need it, but not always, need to check the heads to see if they can be skimmed (if done before oo many times there is a limit) and even if they need skimming.

All in all I am unconvinced with the diagnosis, if it is right and everything is done properly price is OK

Nige

Where can i get a compression test done ??? or how do i do it????

my car is Automatic so just put in neutral and let it coast to a stop without using brakes yeah???

appreciate all this advice

[Dave W]

Be warned, there is a guy working out of Thirsk who has been responsible for screwing up a number of Land Rovers recently. He claims to be a qualified Land Rover mechanic but has no such qualification and has cost his "customers" a fortune to put right his "repairs".

I've seen the results of his work at Maddison 4x4 (as the local Land Rover specialist they usually end up picking up the pieces) where some of his victims have had to have the work rectified afterwards.

Not saying it is the same guy, more of a warning that you need to be careful who you pass on your hard earned to. There are quite a few good and trustworthy garages and mechanics in the area. I can recommend Maddison 4x4 or Station Autos myself, not had any experience with the others.

[Hybrid_From_Hell]

http://cgi.ebay.co.uk/PETROL-ENGINE-AUTOMO...A1%7C240%3A1318

This would do

Don't also ignore the advice re checking radiators not block, thermosats etc etc etc

Nige

[teessidelad25]

Be warned, there is a guy working out of Thirsk who has been responsible for screwing up a number of Land Rovers recently. He claims to be a qualified Land Rover mechanic but has no such qualification and has cost his "customers" a fortune to put right his "repairs".

I've seen the results of his work at Maddison 4x4 (as the local Land Rover specialist they usually end up picking up the pieces) where some of his victims have had to have the work rectified afterwards.

Not saying it is the same guy, more of a warning that you need to be careful who you pass on your hard earned to. There are quite a few good and trustworthy garages and mechanics in the area. I can recommend Maddison 4x4 or Station Autos myself, not had any experience with the others.

hello thanks for your advice the garage ive had a quote of was a mate of a mate garage called CJ Autos in Thirsk near A19.

My main concern for it not being the head gasket is where is all my water going its not in the oil as ive checked this and no smoke, or steam and no misfires????????

[Ivan]

Not quite as technical as the grown ups above but, one problem I had on my 1991 Discovery V8i was losing water from the system. I checked everywhere and no water in oil, no smoke or steam etc. I eventually found the fault was a split heater pipe that was leaking into the valley area and running down the back of the engine. It did not show up under idle conditions only after driving for a while. The split was only small so only showed itself when the thermostat opened and the water go up to pressure (IYSWIM).

HTH

Ivan

[teessidelad25]

Not quite as technical as the grown ups above but, one problem I had on my 1991 Discovery V8i was losing water from the system. I checked everywhere and no water in oil, no smoke or steam etc. I eventually found the fault was a split heater pipe that was leaking into the valley area and running down the back of the engine. It did not show up under idle conditions only after driving for a while. The split was only small so only showed itself when the thermostat opened and the water go up to pressure (IYSWIM).

HTH

Ivan

Mine seems to be losing water only when i rev so not sure if this is the same problem or not gonna be a hard one to find i think. did u consider the head gasket ?????

[Ivan]

Mine seems to be losing water only when i rev

Thats exactly what mine was doing. When you rev the engine the water pressure get up because the water pump is moving faster. I solved my problem by replacing the hose. The other thing was, the water was leaking onto the exhaust so was evaporating quite quickly. Might be worth getting someone to look around the engine while you rev it and see if they can spot any water leaking out.

HTH

Ivan

[teessidelad25]

Thats exactly what mine was doing. When you rev the engine the water pressure get up because the water pump is moving faster. I solved my problem by replacing the hose. The other thing was, the water was leaking onto the exhaust so was evaporating quite quickly. Might be worth getting someone to look around the engine while you rev it and see if they can spot any water leaking out.

HTH

Ivan

when i rev mine the water in the expansion tank is bubbling thou i'm assuming you didnt have this ??

[Ivan]

It may have been but I never looked.

Ivan

[Hybrid_From_Hell]

You can also get cooling system "Dye" which you add to the system, helps spot the leaky poos

Nige

[Somadoc]

Its all coming back to me now!

I posted a similat `heart felt` plea for help at the end of December when my 2000 4.0se started spewing water everywhere and putting the temperature in the red zone.

Since then I have replaced the thermostat, radiator and viscous fan, hoping to `sort it`. I thougt I had until yesterday when I replaced the exhaust system, drove 15 miles and checked the cooling level only to discover a big fat and swollen top radiator hose. No water loss, no overheating but it loooked as if it should have burst!

Reading this post makes me wonder if the block has cracked and I am just sticking on plasters whilst avoiding the inevitable. I will replace the top hose (ever hopeful) may consider `Irontite` although I have been told by a number of people its rubbish. Too good to scrap? Whats the alternative?

Cheers, Robin.