intermittent overheating p38

please help.i own a 200 4.6 vogue , i have been encountering overheat problems since purchase, i have driven to france towing a 26 foot caravan and it doesnt miss a beat,, on the occasional short trip not towing it overheats causing the top hose to become absolutely solid .

if i rev the engine the top hose goes solid ,
i have fitted brand new radiator and blown the top off

had 2 thermostats fitted

still the problem persists

i have since removed the heads and found no visible problems?

removed the block and washed water through both without finding any blockage

the car has covered 70 000 miles since new and the engine is spotless.

can anyone suggets anywhere else to check as the problem is only intermittent but the hoses are solid hard as soon as i rev the engine ,like a pump they go up ..

all help appreciated

thanks

problemchild said:

please help.i own a 200 4.6 vogue , i have been encountering overheat problems since purchase, i have driven to france towing a 26 foot caravan and it doesnt miss a beat,, on the occasional short trip not towing it overheats causing the top hose to become absolutely solid .

if i rev the engine the top hose goes solid ,
i have fitted brand new radiator and blown the top off

had 2 thermostats fitted

still the problem persists

i have since removed the heads and found no visible problems?

removed the block and washed water through both without finding any blockage

the car has covered 70 000 miles since new and the engine is spotless.

can anyone suggets anywhere else to check as the problem is only intermittent but the hoses are solid hard as soon as i rev the engine ,like a pump they go up ..

all help appreciated

thanks

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Get somebody to so a sniff test to make sure it aint head gasket problems first, they seem to be bad for that, foked liners.

if its pressureising beyond normal then its gonna be liners/head or head gasket. these all need testing or swapping to be sure.

the only other thing is air locks.

if its lpg you could also get pressure from that. turn off the lpg and run on petrol. be sure to run any residual lpg off and if it persists it gonne be the above.

there is no other way i'm aware of that will cause the high pressure in these engines and i have hoped for any of the easier ones!!!

if its only intermittent try irontite or k-seal first maybe!!

yes i have removed the heads and block..the sniff test showed no results! the gaskets are in good order

do i need skim heads
replace bolts
skim block ??

please advise

also is it possible to test liners????

you should see the liners. take a few piccys and email em to me make em good ones of each cylinder. if you can see the outline of a liner then i would say its the liner that has slipped. the block should look like one piece of metal.

you should really skim heads every time unless you are comfortable in checking them for flatness. i think the tolerance is 0.05mm or something stupidly small like that!

replace the stretch bolts, they are around 20 quid.

did you test the lpg system for leaking into coolant? it wont neseccarily show up on a sniff test.

you can have the block re-decked but that means taking it out to be machined. obviously this is a ball ache but if you have heads off its not that much more work, ive had mine out twice in recent weeks and i'm a bit of a dab hand now. i can more or less talk you thro it if you need!

the pressure can only come out of the pots and into the coolant(or from lpg) also air locks can cause similar symptoms to h/g or liners but its usually not as severe.

pm me when you have the pics and i'll send you my email(unless its on my profile) or post the pics here and we can all have a look.

dont clean the pistons yet and also pics of heads, dont clean em either yet.

hope this helps!!

ty i will photo them today

fingers crossed