p38 cooling issues

hi everyone!

having serious issues with my range rover 2.5dt overheating, changed the engine as the other one had a cracked head new engine in it now overheats when i drive after about a mile, would a expansion cap cause overheating?
really stuck here took thermostat out new rad and new water pump still the same aaahhhhhh!

IIRC ....Didn't someone post on here recently about a "Baffle" in the Rad & checkin if one is fitted by rolling a Marble into it?????


From Memory if the baffle is missing the water just flows accorss the top of the rad & (Obviuously) doesn't cool it causin overheating.... if the "Baffle" is there it forces the water down the rad & up T'other side there-by cooling it & "Normal" operations are resumed!!!

the hooded claw said:

IIRC ....Didn't someone post on here recently about a "Baffle" in the Rad & checkin if one is fitted by rolling a Marble into it?????

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Hiya, yep I posted that a few days ago. Bizarrely though the post that I was replying to was from the same person as this one - have you still got issues Hendoaaron ?

hi there

yeah still got issues didnt get that reply though, maybe i did but didnt read it correctly, well funny you should say that cause top of rad is dam hot bottom is cold as.
its a brand new rad in her though stange have i bought the wrong rad or something?

me again so how do i check its got a baffle put a marble in? if there isnt one is it a new rad?

many thanks for all your help this site is great

hendoaaron said:

me again so how do i check its got a baffle put a marble in? if there isnt one is it a new rad?

many thanks for all your help this site is great

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Aaron, Yous gonna have to remove the rad & roll a marble into it ... IIRC hold the rad upside down & roll in the marble tip it to the right & if it rolls out at the other side it aint got a Baffle in it & it won't work on yer P38 e.g. NO COOLING!!!!

ok!

ill get straight would make perfect sense, so is it a easy fix if it doesnt have one? its weird though cause before with my old engine it would overheat while stationary but cool when driving! like i did a trip from lancaster to bourenmouth not a problem, surely if no baffle was there is wouldnt cool then.

hendoaaron said:

ok!

ill get straight would make perfect sense, so is it a easy fix if it doesnt have one? its weird though cause before with my old engine it would overheat while stationary but cool when driving! like i did a trip from lancaster to bourenmouth not a problem, surely if no baffle was there is wouldnt cool then.

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When yer drivin your forcing Cool Air thru the vains of the rad there-by cooling the engine when Stationary the only "Cool" air being pulled thru the Rad is via the Viscous Fan blades & if the Viscous Coupling is Shagged you'll get even LESS air accross the vains & it will overheat

There is a very common mis-conception that the fan on the front of an engine "BLOWS" i.e. it Blows air thru the rad ...IT DOESN'T IT SUCKS....

If yer think about it its obvious ... it spins ANTI Clockwise its SUCKING from the front & Blowing TOWARDS the engine


Most People Assume/think it "Blows AT THE RAD" .... it actually SUCKS THRU THE RAD!!!

cheers mate!

all sounds good makes sense, heard people saying that before, im away off here to take this rad off and ill let ya know later how its goes. fingers crossed its the rad that would be such great news. vicous fan is working fine, so will i need a new rad if its not got one?

sorry me again!

how do i know my fan is working for definate?

hendoaaron said:

cheers mate!

all sounds good makes sense, heard people saying that before, im away off here to take this rad off and ill let ya know later how its goes. fingers crossed its the rad that would be such great news. vicous fan is working fine, so will i need a new rad if its not got one?

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You wont need a new rad . If its the ally core with the plastic end tanks take it to a rad place & ask them to decrimp it to check for the baffle. It will take half hour to decrimp & recrimp it.

ok im back!

didnt have a marble but put a 10mm nut down it seemed to stop halfway across so take it its a baffle in there, so now im back to square one, why would my range sit at 12 0clock when idleing then shoot up when i drive. thinking head gasket or head but showing no signs of bubbling in expansion tank, water in oil, oil in water not losing coolant either!

just another thing why would my top half be warm and bottom half cold on rad?

very bizarre

me again!

after my drive the top and bottom pipes are rock hard i mean solid, replaced expansion tank as well still the same.

hendoaaron said:

ok im back!

didnt have a marble but put a 10mm nut down it seemed to stop halfway across so take it its a baffle in there, so now im back to square one, why would my range sit at 12 0clock when idleing then shoot up when i drive. thinking head gasket or head but showing no signs of bubbling in expansion tank, water in oil, oil in water not losing coolant either!

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Ok Aaron, here a Fast/no cost way to check the Head Gasket ...........

Either Drive it to yer local MOT testing station ... Ask the tester to shuv his Exhaust gas analyser Probe into the expansion tank ..........IF its registers Hydro Carbons (Exhaust Gasses) then yer HG is screwed or yer Block is cracked.

IF you can't drive it there .... Warm the engine & syphon off some water into a Pickle Jar (Or a jar thats at least got Rubber sealed top) ...

Take THAT to the MOT testing station & Ask him to Shuv his Analyiser probe into the jar..... Again if Hydro-carbons (Exhaust Gasses ) are present then yer HG or Block it Goosed!!!

Just thinkin here when you say it "Overheats" I'm assuming its blowing out of the Expansion overflow pipe..... You HAVE checked the Rad cap fer damage have'nt you ??????..........................

hi hooded claw!

many thanks for speedy reply, good thinking about the jar thing genious, the water isnt coming out of overflow, in expansion tank the level stays the same till crank the cap obviosly then it boils not good for engine.
any theorys?

oh and yes replaced expension cap brand new one today

hendoaaron said:

hi hooded claw!

in expansion tank the level stays the same till crank the cap obviosly then it boils not good for engine.
any theorys?

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Aaron,

Here hang on a minute, We (I) assumed it was "Liftin the rad cap seal & chuffin water all over everywhere".......... But...... Readin that post above you said " When you Crank" (by that I assume you mean open) the Expansion cap it "Boils" ............ Well it WOULD its a PRESSURISED SYSTEM & your letting the pressure out.............

I assume your Temp gauge is goin into the red area ...............but with no loss of coolant & no leaks ................. you COULD be looking at a simple AIRLOCK in the system ..... Does the heater blow hot???

When you fitted the "New" engine HOW did you fill up the Water sections (Via the Expansion tank or thru the "Bolt hole" on top of the rad ....) And did you run the engine with the Expansion cap off & keep topping it up ??? (as the pump pulled water from the tank ??)