Ok so here's the story.

3.5 efi in a 92 disco. Few mishaps over the years but overall runs sweet. No problems to speak of.

Went on a laning trip from tuesday 27th to Thursday 29th.

On Tuesday drove the car from Manc 112 miles to north yorkshire. Mostly motorway, 2500rpm.

At approx 105 miles, decided to stop at a garage to top up with fuel. Stopped at the pump and noticed steam. Jumped out and a healthy amount of coolant was ****ing out from front of engine area. Quickly turned off and opened bonnet. Coolant running down front of engine, collected around dizzy and small amount sitting down centre of valley.

Restarted, no leak obvious. Added around 1ltr of water and had to carry on. Got to meet point and leak still apparent, dripping off front of sump etc.

Spoke to mates and decided to fill to level and then leave header tank cap JUST nipped to allow pressure to escape. It was not loose, seal just engaged.

Drove the car like this for 2 days of laning, kept revs below 2000 mostly apart from when needed in bogs, because high revs gave a whiff of coolant though the vents. Did 100 miles first day, used about half a header tank. Topped up, same next day, drove home 120 mile and used about 2ltr probs.

Definitely not a massive leak then.

Now for pics. You can see in one pic there is a wet stain on the drivers side front head face, near the oil pressure switch wire. This stain has been there as long as I can remember, so it must have been weeping for ages, but I have never had to top the coolant up more than a half a cupful or so every few months or whatever.

Was driving the car about yesterday, running just fine, same this morning, header tank now nearly empty, but not topped up since halfway down motorway on Thursday.

I can't see it being a hose cos it's too small a leak and can't find the source.

Was just hoping someone might recognise it, otherwise I guess it's valley gasket and front cover gasket. Wasn't quite ready to strip the motor til I bought new cam and valve train components!

Interestingly the back end of the valley gasket is dry this morning, after a good flat out session yesterday, just the front end of the engine is wet...

Any help appreciated!

Hows the temp?

Waterpump gasket?? or a porus pipe or pinhole in hose. they sometimes go where the hose clamp sits.

the temperature has not budged at all. perfect up the motorway, perfect throughout the whole laning trip and ever since, not budged from just over half on the guage, which is normal.

on first warm up, temp climbs to just under 3/4 then quickly drops, as thermostat opens i guess.

yeah joe i did think pinhole hose or weeping joint, but on preliminary inspection the hoses are dry. when i first popped the bonnet the system was still at full pressure and i couldnt see a leak or where it was coming from. no steam or visible flow. once i let the pressure out at the cap it never seemed to leak proper again. as i say, i managed like this for two days and it leaked slowly.

hoping some expert can recognise the fault, otherwise its systematic diagnosis

cheers!

Hi. It seems like you might have a cracked head, as soon as the temperature rise it seeps out of the crack. Drain your water and flush the system with clean water to get all the anti freeze out. throw in stop weld or radiator weld in and fill the water system up. read the instructions on the bottle how long and how to use it. Drive for 100 miles low revs and with no load. drain the water and throw in clean water without anti freeze, the anti freeze doesn't work with the radiator weld or stop weld, drive with the clean water for a while before you throw in anti freeze again.

I think that it could be that little ****er of a hose that feeds one of the heater intake lines, the one that in the back and hard to get to. Often it gets skipped in the replacement cycle because it ain't easy to get at. It doesn't get pressurized until the thermo opens so you can miss it at start up.

When mine blew I went to Land Rover and they said "Yes sir, we have one for your Classic and it will be $49.95" for a freakin' 6 inch hose with a certain little bend on it.
I went to AutoZone and bought a hose with the right bend in it but about 4 inches to too much hose on either side of the bend, and cut the extra off and fitted it. That one cost $11.00.

thanks for the ideas so far guys.

a cracked head does seem extreme but then i suppose it could be an option.

a hose also could be, its certainly that area, but the heater circuit pipes felt dry as best i could see.

the 90 degree hose does contact the front of the drivers side head so it could have rubbed through, although it doesnt look like its coming from just there!

i might have to get it up to full pressure again and see. or maybe get the system pressure tested?

i have had good results with radweld/irontite in the past so thankyou theo for your advice on that.

this engine only got overheated once, about 18 months ago when i forgot to turn the electric fans on. it was on tickover and all of a sudden blew the coolant out of the expansion tank cap.

i let it cool and then drove it home 50 miles, and havent had a coolant related problem since.

it now runs the viscous again anyway becuase the electric fans couldnt keep it quite cool enough.

still waiting to hear from fett/voguese/3.5efi/pornstarmax/poah/jamesmartin and other associated experts

cheers!

on the cracked head idea, how do i explain the damp area that has been there for a long time?

is it more likely that a gasket leak would weep for a long time and then suddenly give way, or is it more likely that a head crack would weep and then suddenly open up on the motorway, with no other signs. and would a head crack allow 2 days of full temperature green laning without losing a significant amount of water?

hmmmm.

try hose at rear of plemun chamber . bugger to get at though . possible manifold to heads leaking ??I'm sure there's a water way on one head at the end , can't remember where exactly though !

Gotcha:



It's the front of inlet manifold to solid heater pipe hose.

Gave a squirt when revved up, and that's with the cap off!

Developed a misfire yesterday, I hope it's the dampness.

Where to get a hose at 3pm on NYE?

Result , if only they were all that simple !!!!

super glue , work's for a few heating cycles .

yeah im glad its nothing more serious. good old motor this one of mine, was starting to lose faith!

found a length of 19mm bore gates fuel hose, its very thick wall so will be awkward to get to, but should do for now. failing that i'll try to glue and tape it.

the pipe had worn through on the edge of the front valley gasket retainer plate. might be worth checking yours!

hoping that i can give the dizzy a quick service and sort the misfire issue. odd becuase mine is fully sealed and it looks clean and dry in there.

moody, but reliable

Mr Noisy said:

still waiting to hear from fett/voguese/3.5efi/pornstarmax/poah/jamesmartin and other associated experts

cheers!

Click to expand...

Wotcha need them guys for when ya got me..

Mr Noisy said:

the pipe had worn through on the edge of the front valley gasket retainer plate. might be worth checking yours!

Click to expand...

Told ya it was an hole in an hose.

be VERY careful lifting the rotor arm , use a small screw driver to hold the shaft down , or , you will probably displace the bob weight's at the bottom of dizzy . complete strip for that and dam fiddley to .

Cheers joe, I'll pm you next time!

Thanks Elsie, have already rebuilt my dizzy as it happens, because one advance spring stretched somehow.

It was a fiddly job but quite rewarding. Having just lifted the cap I found a fair bit of biscuit colour crust on each of the tower contacts, removing it and cleaning the arm seems to have sorted it. Probably not far off needing another cap.

Anyway, successful day so far