Go Back   D24T.com > Technical Discussion Area > Diesel Engine and Drivetrain

Thread Tools Display Modes
Old 06-22-2019, 06:47 AM
Rederic Rederic is offline
Junior Member
Join Date: Jun 2019
Location: Europe
Vehicle: Lt31
Posts: 4
Default Losing coolant

Hello all Ė
Thanks in advance for your help.
When Iím on the highway are usually keep it running between 3500 3800 RPM.
Iím driving a Volkswagen LT 31, westfalia camper van.

It was getting a bit hot earlier but I added a coolant additive and I drop the temperatures down a little bit.
It seems that it burns about 1 L of coolant for every thousand kilometres of higher RPM highway driving.
The temperatures are not climbing.
But when I add coolant there is a little bit of pressure.
Iíve noticed a little bit of smoke too so Iím wondering is this amount of coolant loss normal at these RPMs and operating conditions?
I canít notice any stains on the ground underneath the engine in the morning.
Iím going to closely examine all the hose connections later to see if I can see any dried residue.
Any thoughts?
Thanks in advance
Reply With Quote
Old 06-22-2019, 03:00 PM
RedArrow RedArrow is offline
Senior Member
Join Date: Jan 2013
Location: NY
Vehicle: 740
Posts: 577
Default Bad news if you are on the road but dont panic. Inspect details immediately

That is something you must fix asap,
The cooling system is hyper-sensitive in these cars and must be in top notch condition otherwise catastrophic engine failure may (and Will) follow. And it happens very quickly.

The cooling system must be completely well set, no leaks whatsoever and it all must work perfectly to avoid overheating, at all times!!

I would check the area under the thermostat where many of them often leak. It is probably not where you may find the leak/ a leak this time though. Bc you said you cant see leaks present...
Check all coolant hoses and all their clamps.
Look for signs of a leak or air intrusion.

I would get a few bottles of carbcleaner (brake parts cleaner?) spray to spray/clean surfaces for best results for your visual inspection...---in case your engine is very oily and dirty**
But, try to avoid getting chemicals onto hoses of the cooling system.

Hopefully your radiator doesnt leak either. It is sometimes hard to spot it there though.
What is the status of the cooling components?

Waterpump replaced lately? That o ring often leaks too right after the tb service...again idk if you had any service performed lately. If yes, suspect those components first.

Thermostat replaced when? If, at all.

Any sympthoms when you look into the engine?? do you see milky substance? Greyish color of the engine oil? Or maybe at dipstick? If you got the valve cover off, did you see/look for "Sweatspots" that look like water vapor? Hopefully NOT the case. if you do see greyish milky oil, dont drive it at all. Headgasket is sick ...IF IF oil mixes with water or vice versa.

Any hoses replaced lately? If yes, you may tighten the clamp a little by lottle..if you see the leak. This is best done when warm.

If you can have cardboard under the car, check in the morning what happened overnight.
It is easy btw to lay under the car and inspect for wetness. Engine rear hose may leak too if inj pump and valve cover have been leaking for yrs. But dont go there first.

Check oil.
Check for overheat on the dash gauge in case you must keep driving.
Check for leaks.
Air in the cooling system isnt good at all. If it us exhaust gasses that create that pressure than pls dont drive. Does it smell?

BTW, how does your exhaust fume smell at the tailpipe? Inspect that too. Shouldnt be a sweet smell. Shouldnt see whiteish haze in the smoke unless it is the first 30seconds of a coldstart. You mentioned additional smoke. What color? How much? When? Any rpm or only at heavy load / higher rpm? What speeds?

All these, might indicate some underlying issue so think of all of them a little bit. If the car drives great otherwise and there us zero power loss then you should not be extremely wirried but you still must get the issue found AND fixed right away.

1liter coolant loss is waaay too much. Entire system is 11liters.

If the car had zero issues for a long time *and* if there were no recent services done, you probably just have a leaky weak hose.
Overtightened clamp on coolant hosescan may also result in air intrusion which may push out near your expansion reservoir.
Is that area dry??? And how is the cap on it? Wet?
(There is a valve inside there.)
When a used coolant hose is reused and when a clamp is reused or simply turned, retightened, it may result in an imperfect sealing so think of this too. Any cooling system update done recently? Even if it was just a flush. Or a replaced hose? None of those?

You need to find where the coolant goes.

Please see signs of oil in coolant.
Check to see signs of waterin oil. Do this as step one
And if you must drive then have multiple gallons of distilled water or coolant with you.
And check back here bc the forumers know every little part of your engine.

I just wanted you to read about what id do on the side of the road if i were you.
Best of luck and be safe.


No coolant loss, any coolant loss is normal, under ANY conditions. Coolant loss kills these vehicles rapidly. Watch it like an eagle. If necessary, stop driving it. Maybe get the rad tested if near a shop but i would think that isnt the case here.

You have coolant loss that is not normal, at all (the amount).

Also important for us to know :
-since when (or appr how many miles ago) has this been happening?
-is it something that got worse then worse in time?
-is it something (the coolant loss) that you always had?
Or there were times when nothing at all went "missing"?
-write about recent updates (if any) And all modifications and repairs you have had.
-are you familiar with this engine setup, do you have tools with you?

Such a fun car!! Where in Europe? What engine? D24 nonturbo or turbo version? Intercooled??? One of my brothers own an LT35 flatbed the little cargo truck with the rear platform...not the car hauler flatbed.1986 nonturbo 4sp manual with only 70.000km in the stock factory configuration, a rare, mint beauty with the facelifted front. Runs like a champion.
Welcome to the forum!!

"It was getting a bit hot earlier"
Was it the weather hot?? Or was it (the car) hot??

Last edited by RedArrow; 06-24-2019 at 04:56 AM.
Reply With Quote
Old 07-11-2019, 01:31 PM
jpliddy jpliddy is offline
Senior Member
Join Date: Jan 2014
Posts: 150
Default 940 tdi auto 1995

thank you for the information red arrow
Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT -8. The time now is 03:49 PM.

Powered by vBulletin® Version 3.8.10
Copyright ©2000 - 2019, vBulletin Solutions, Inc.