I'm changing it as the engines overheating so this was the first place to start


I'll go attempt it again bringing the water to a boil rather than pouring on straight boiling water, as long as theres no chance of making it fail by overheating ?
 
Yeah top hose hot, bottom hose warm-cold, top rad hot, bottom cold, nothing much moving to expansion tank
 
unless you have bottom hose thermostat like p38 top hose hot meant it was working , cold parts of rad arent cooling
 
I thought it would be cooling as the bottom hose was cool ish to the touch ?

If not how would you suggest fixing it, getting the rad replaced or fixed somehow
 
rad does get cooler toward bottom but not cool the idea is that temp is maintained and not cold water going into engine ,that rad removes enough energy to achieve this , new one or recore ,if top hose hot it has to have open thermostat or none ,ive had blocks half full of corrosion and crap when core plugs removed causing over heating etc
 
I found a defender V8 rad, would that fit into it as its an alloy one not the standard black one

I'll change the thermostat over anyway as I've got a new one that probably better than the current one thats fitted.

Could it not be a problem of thermostat stuck slightly open i.e. enough to let flow through but not enough to let all the hot out ?

I'm just trying to think cheap haha as funds for it are running a bit low
 
Ahhh reet, I'll see about getting one from a RR then, theres a few 4.0 and 4.6 ones on ebay at the mo for under £100

It can be made to fit, I should have enough room to put it in if not something of the same dimension from a different vehicle
 
I'd be tempted to get a sniff test done as the old carb v8 overheat relatively sedately with hgf and tipped heads are the reason rover removed the extra bolts on later heads
 
Exhaust gas analyser. Measure hc under bonnet and over radiator bung open .if it jumps you have hgf
 
Ahhh ok thanks, well that might be the last resort then


I'll test it once the chassis is welded back together and the full exhaust is fitted to make sure all gasses are escaping correctly etc


So my checklist as it stands is in order of ease;

Thermostat - changing as soon as I get a chance

Vacuum fail - spray WD40 round throttle body

Water pump fail - replace or hand crank to test for stiffness I guess, only other thing I can think of is it could be running slow as its being driven off the alternator belt rather than on its own one but I doubt that should affect it unless someone put the wrong size pulley on it too so it's running slow

Rad blocked - no idea how to test that one so probs have to just get a new one fitted

HGF - Sniff test as suggested and if it's ****ed engine rebuild :frusty:




Oh actually one last one, if the carbs are running wrong could that be causing it by making combustion too hot alongside another smaller factor like a ****ed water pump
 
Moment of truth tomorrow :( finally going to change over the thermostat as the weldings all done now, so after a morning fibreglass and chemical metal session to cover all the small holes I'll be swapping the thermostats over

Praying I find the old one jammed slightly open if not I'm really dreading this

Talking to a mate today he said one of his friends had a V8 and the big end had gone or something like that and it was the cause of overheating so again thats another thing to add to the list of paranoia

Might end up just cutting my losses and selling the bugger if its going to be something extortionate, full engine rebuild will bankrupt me at this point :p
 
maybe slipped liner , prob not big ends causing over heating.

chemical metal on what? chasis or stat housing? either not good !
 
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maybe slipped liner , prop not big ends causing over heating.

chemical metal on what? chasis or stat housing? either not good !

James martin reckons its the rad thats ****ed given the symptoms I mentioned on my rebuild thread, replaced stat today and was gonna fire it up but battery was dead. On replacing the stat found the old one only opened 2mm in boiling water which is less than the new one so hoping its just that but will have to wait til I get a new battery later in the week to find out

Might have an old boat battery somewhere that might work so gonna try that before buying a new one

Tried to take the battery out of my disco and it set the alarm off so gave up


Chemical metal is for a couple of small holes on the inner bulkhead and a small gap on the outer, keeping it well away from engine parts haha




However I've found a Rolls Royce 6.75L V8 so I might pull the trigger on that if I can get a bit of extra cash together.
That'll sound awesome and give ****loads of power

OR if not theres also a 4.2 straight 6 from a Nissan patrol that would work
 
Might be worth me chucking in my 6 pence, I got a 88 running a tvr challenge 4.3 with stage 3 mods.... The rad is a **** part hd rad that I had new for 2.25 lump.... I have ran it all through summer and has caused no overheating problems at all. I was going to put in a flash ali rad in, butvas **** part one has not caused a problem, I will stick with it..... Might be worth looking at one as they are cheap!
 
Well I've decided to just take it to the local garage to see what their diagnosis is and go from there as they can order any part and fix most problems


If it's a headgasket I'll dismantle the top of the engine on site or just off it on the private road if health and safety is a problem in an attempt to save some cash (might as well as it's £34 an hour for a job I could do)

Then just wheel it back in on the back of one of their 110's for the change and they can put it back together so it's all done properly
 

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