.... another overheating problem (soon to be followed by what's the best oil...)

PanoZen

Member
Apr 1, 2018
5
0
USA
Hello,

Lurker and owner of a 2000 LR Discovery II with 196k miles
Head Gaskets done - about 20-30 k ago
Replaced all hoses with Atl-Brit set last year
Replaced Trans with a 2004 Tranny
... and more.

I've had the truck for over 5 years (2nd owner) and do what she needs when she needs it. I accept and embrace all the eccentricities of the ol' gal, and bless her for her strengths.

But now, I'm stuck - and so is Dave at Atlantic British and the Rovers North folks....
Truck has been eating coolant for a while but it has now become serious - can't go far without jugs of distilled water in the back. I lose coolant too quick to keep replacing with antifreeze and I live in the Southeast - Virtually no chance of sub-zero temps anymore.

@Steps taken so far -
Flushed and bled cooling system - went fine - held reservoir up and burned sage smudges
flush and reverse flush heater core - good flow (also - passenger side footwell is dry)
Purchased exhaust gas tester - and liquid remained blue after several tests - even tested the tester by performing a colonoscopy on my truck with the
tester and the exhaust pipe. Turned yellow immediately.... as most people do under similar violations...
two new thermostats (in case the first was bad)
no obvious leaks or evidence of pressurized steam escaping. Ground is always dry underneath also.

but after running the truck or driving 5-10 minutes then something seems to clog and I start overheating which causes coolant to bubble out... (my working hypothesis) .
I'm leaning toward a new radiator just 'cause they all need one every 30 oil changes (@3k miles per change).

But I don't want to just start throwing more and more parts just hoping one may fix it. I may go through and swap out all the silly hose clamps with new SS ones when I do the radiator. But I'm fishing here on the clamps - no actual evidence of breakdown, just thinking they may lose their tension under pressure after 20 years.

Does any of this sound familiar to anyone? Coolant disappearing causing truck to overheat - but no evidence of any leaks, cracks, blown gaskets, etc.

Thanks in advance...
Stu
 

PanoZen

Member
Apr 1, 2018
5
0
USA
Any white smoke?
Can you smell the coolant burning off?
No smoke at all ... and only occasional burning off smell and that probably was from the reservoir boiling over. She cranks right up, good power, steady idle - absolutely clear exhaust - no white (coolant), blue (oil) or black (too rich). None of this makes any sense... Thanks
 

PanoZen

Member
Apr 1, 2018
5
0
USA
Cracked block
Hmmm... That would be a gut punch.... Any ideas on how to test for it? This unfortunately could be a possibility I guess, but I don't see any thing coming out anywhere. May soon be followed by a post "Looking for an engine... " Actually, there is a local LR mechanic who put a 4.6 turbo gas engine in a disco. I don't need worse gas milage but it is a clean job and the truck flies...
 

Toran

Well-known member
Feb 3, 2017
347
31
Ohio
If it is a cracked engine block and you are planning on tearing it down you could try a bottle of BlueDevil Radiator & Block Sealer.
 

Blue

Well-known member
Mar 26, 2004
9,399
462
AZ
Exhaust gasses are probably over-pressurizing the cooling system.
 

p m

Administrator
Staff member
Apr 19, 2004
14,866
369
56
La Jolla, CA
www.3rj.org
It can easily go into the oil past the timing cover to block gasket.
The oil temperature is high enough to cook off the coolant so oil level doesn't rise unless there is a profuse leak.

That all said... I had an 89 Classic with a cracked block. It drank coolant like there's no tomorrow, yet no signs of exhaust gasses pressurizing the radiator hoses or white smoke or oil level or appearance changes.
After three head gasket jobs, I passed it to another unsuspecting Discoweb member. Then off it went to another...
 
  • Like
Reactions: Howski

Blue

Well-known member
Mar 26, 2004
9,399
462
AZ
What do you smell? Coolant could be pulling a virga and evaporating before it hits the ground. You mentioned coolant "bubbling out" in your first post. Is the expansion tank burping out coolant? Has your cheap shit plastic expansion tank cracked yet?
 
  • Like
Reactions: Howski

Swedjen2

Well-known member
Sep 12, 2018
552
111
California
It can easily go into the oil past the timing cover to block gasket.
The oil temperature is high enough to cook off the coolant so oil level doesn't rise unless there is a profuse leak.
In my 2004 D2, I've got a slow coolant leak - about 1/2" of coolant drop per 250 miles or so. No smoke, no drips, no pressurized hoses,
no foamy oil.
How does it get past the timing cover to wherever it goes next?
Where does the coolant flow in relation to the timing cover?
More importantly, what's the fix? A new timing cover gasket?
 

DiscoHasBeen

Well-known member
Aug 7, 2016
809
166
Indy
Dude, a little advice from a guy who had the same issue (overheating) with the same vehicle. If you keep running that thing it will, if it hasn't already, fail. You might as well pour sand down the oil fill opening. So, you either need to figure out how solve this problem without running the engine until the coolent boils over, or just move on to the rebuild/new engine.
 

p m

Administrator
Staff member
Apr 19, 2004
14,866
369
56
La Jolla, CA
www.3rj.org
How does it get past the timing cover to wherever it goes next?
Water pump sucks coolant from the bottom radiator hose, and sends it through two ports in the timing cover into the block.
If the timing cover gasket is hosed, coolant can seep into oil galleys.
 

Swedjen2

Well-known member
Sep 12, 2018
552
111
California
Thanks, P.M.
Well, the p.o. who rebuilt my engine had never rebuilt a V-8, much less a Rover V-8.
At least he sent the block to D&D for the machining and top-hats, but he put most of it back together himself.
It's always had the slow coolant loss since I've had it...@15K miles.
 
Last edited:

Flyfish

Well-known member
Oct 29, 2004
1,026
69
49
St. Louis
A compression test may show something. Also, add a UV dye to your antifreeze and then you can look to see where it shows up.
 

PanoZen

Member
Apr 1, 2018
5
0
USA
Hey, I really do appreciate the feedback -
@ Oil & Water - no coolant in oil or vice versa - tested
@ Running it until it boils - fan comes on but temp gauge is still good - and if it blows the engine - well at least I know what to do then. I'm not letting it do a melt down though. but I am looking for the leak...
@ only three places - agreed - that's the quandary - it's not showing up anywhere...

At 200k, I've always known an engine may be a possibility. But there are also a lot of folks who have gone 300k plus with their original engines.
Part of me says - start throwing parts (radiator, etc and work my way back to the firewall) and maybe I'll get lucky. Maybe there is just a chunk of antifreeze sludge moving around that is causing a blockage. And if I need a new motor, then I'll already have new cooling parts - one less thing to worry about.

I just hate the "throw parts until you fix it" approach. I prefer to know what's broken specifically - not just - it overheats.

I've had British cars and bikes off and on throughout my life and this is not the first whacko incident. I just keep telling myself they had one of the most successful prop planes in WWII (Spitfire), their old bikes are legendary (Norton, Triumph, BSA), all their vehicles have always been "interesting engineering"....

Thanks again for the suggestions -
-sm