Overheating question

[jrman]

OK, here's what I suggest:
1. Ask the guys that did the work what Thermostat they put in? What Temp does it open? You might have the wrong one in.
2. Pressure test the system to check for leakage,
3. Check Coolant mix (Important) Make sure you have the recommended Diesel Heavy Duty Coolant,
4. Check your Rad hoses to see if they are getting soft. You don't want them to expand under heat. Messes up the pressurization, Pressurization keeps fluid from boiling.
5. Make sure you haven't "Overfilled" the expansion tank. There are marks on it for Hot and Cold levels..
6. With the correct Thermostat, your dash temp gauge should read 1/4 scale. If its reading higher, have it changed.

Experienced the same problem on recent holiday these past few days.
During a long climb, the coolant overflowed into the coolant expansion bottle ultimately over filling it and causing it to escape down the tube beside the battery into the passenger side wheel well. I discovered that the tube from the expansion bottle cap had fallen into the bottle itself. I re-attached it, and to be safe - replaced the radiator cap as well. I have a reasonably new rad, thermostat, and water pump and never experienced this problem before.

I filled the rad and went on my merry way. I could keep the temps at normal levels by adjusting my driving - but have no had to do this before. This morning, I took off the rad cap (big pop sound indicating the pressure was still good from the night before) and immediately some coolant went into the bottle and caused about 1/2 cup to over flow again onto the ground.

My understanding is that the coolant in the expansion bottle is not finding its way back into my rad & ultimately the motor at the correct time.
I noted point 5 on the above post - that I should have removed some of the fluid on the expansion tank to the appropriate hot or cold level (I will do this in the morning and post results). But, I'm still curious why coolant would not transfer back into the rad during the cooling after shutting the motor down.

Thoughts?

[jrman]

I took out some coolant from the expansion tank leaving the level half way between "low" and "high". I did a couple of days driving including some long hills, temps running from low (normal) to half way up the gauge, but no noticeable change in the expansion tank level when hot or cold. Maybe I'm misunderstanding the purpose of the expansion tank, but I thought that coolant should go into it when hot, and return to the radiator once cooled down - thus the levels should rise and fall accordingly.

[Growlerbearnz]

The radiator cap has/is 2 one-way valves- the cap itself is the 'out' valve, with the large spring setting the internal pressure in the cooling system. As the coolant heats and expands it pushes past the large seal against the spring pressure and escapes into the overflow tank.

The second valve, the 'in' valve, is the metal disc in the middle of the cap (shiny and brass in the photos in this thread). The valve should be retained by a weak spring, with the fluid pressure doing the job of holding it shut when under pressure. As the engine cools, the suction in the system pulls this valve open and water flows from the overflow tank and into the radiator again.

If your cooling system is emptying when hot and not refilling, suspect a stuck suction valve. If your cooling system is blowing all its water out as it heats up, and boiling because it's not generating any internal pressure, suspect a failed main valve.

The cheap solution in any case is to replace the radiator cap.

HTH

[TardisDeli]

Hi R2, stop driving it now. This isnt normal for the delica, and the tiny little aluminum engine will warp and very bad things happen, very expensive things. As Chewy said, get Butch and Edwin at CVI in Richmond to look at it, phone 604+247-0500. The wrong thermostat (Lordco) has no long spring on the bottom so wont work and tries to overheat. Another common problem is the radiator gets all clogged with age (look inside where the thermostat should be, do you see scaly white crap, that is bad) but CVI can repair that core clog in their shop.

Mt Seymour road is very long and steep, but as Laura Marsgal wrote, she drives it often so her notes to you are excellent. You might want to drive it slower, I see Delica's passing me on the Cut, and I cringe thinking what the temp guage must be showing.

Cheers, Christine.

[RichD]

TardisDeli speaks truth. Thrashing the truck until coolant overflows is not a reasonable test to keep repeating and scratching your chin wondering whats happening! You are going to blow that engine if you keep it up. Go see Butch at CVI or Glenn at CC Autos and get your cooling system replaced NOW.

Lots of people on this forum and at mini-meets will tell you all the ways you can manage the engine overheating. All of those tricks are basically hacks to manage the problem, but they avoid the fact of the matter: you need a new radiator.

This kind of overheating you describe can lead to cracks in the head. If you just keep thrashing it and saying "I can't afford a new rad", when you finally do the work, the pressure will go up and the cracks will give way. That kind of work is in the $2K+ range of painful.

My own truck is actually doing nowhere near as bad as you describe (I have a pyro and a clue) but I'm getting my rad replaced tomorrow with a clean one, new hoses, thermostat, etc. I think my estimate is around $550 with parts and labor.

Update: replaced the rad today. I can barely move the needle if I try. Cooling system is very happy now. Here's the damage:
- rebuilt radiator (steel head not plastic) $295 (quote was 285, I didn't complain about the 10$)
- hoses, thermostat, new rad cap $170
- labor $150

[FalcoColumbarius]

Dewy: by spilling I mean that the coolant fluid spills when I stop the van after having a drive when the temperature had gone up......

Where is it spilling from? Have you checked your top & bottom rad hoses? When you take the cap off and look into the radiator: How do the fins look? Are they all shiny or do they have corrosion on them?
All it takes to over heat is a fine crack in the rad cap seal, although I found that I would be running hot when travelling down hill, too.

Falco.

[Firesong]

I have to say the same as a few have pointed out.
It should not be doing this.
Something is wrong.. coping by doing the little points is only a means to get you to a shop to fix the problem if you don't have the tools to do it yourself.

I took my deli through the mountains with 6 people in it loaded to the gills and a trailer, through
the passes etc. No temperature increase on the gauge. And yes, all that was replaced when I bought it not that long ago. And I didn't push it that hard going through, slow and steady.

Do get it looked at.

Firesong

[thedjjack]

also have the fan clutch checked

[Rising Sun Auto Import]

No temperature increase on the gauge. And yes, all that was replaced when I bought it not that long ago. And I didn't push it that hard going through, slow and steady.

Do get it looked at.

Firesong

Firesong's comment is absolutely right.
Delica is not born to be speedy, just enjoy diesel torque.
Replacing coolant temperature sending unit and a radiator cap is a good way to avoid overheating .
If anyone needs those, PM me.

Steven

[robinimpey]

Looking for some help. Being proactive I had my mechanic do some work to my van and now I have overheating issues and didn't have any before.

Here's what has happened.
-Alternator replaced.
-Upper and Lower Rad hoses replaced.
-Thermostat replaced
-Water pump replaced
-Radiator cap replaced
-Timing belts replaced
-Oil seals replaced

Now it runs hotter than before and burbles coolant out the overflow tube on the expansion tank and little by little becomes low on coolant.

The expansion tank ends up being full all the time and it doesn't pull coolant back into the rad.

Thermostat was just replaced again in case the first one was faulty, didn't make it better, runs warmer than before.

HELP!

[glenn]

Does it always burble? It could be the cooling system being pressurized by a faulty head gasket/cracked head.

[robinimpey]

Thought of that too, but it doesn't seem to burble all the time and no discoloration of the coolant. And this began immediately after the work was done. It seems strange to me.

[lrp374]

Maybe you still have air from refilling the system? Something that was done must have caused the problem. The thermostat or water pump would be the likely suspects but I think you've already figured that out! What temperature of thermostat did you use?

[robinimpey]

My mechanic is 99% sure that some of the work that was done caused the change and I would agree. It would be a real fluke if the head gasket developed a leak while sitting on his hoist.

I'm not sure what temp the thermostats are. The first one came from Amazing Auto and the second one was bought on CC Auto's recommendation, so they should be good.

My mechanic thought of the potential air lock in the system, so he put it on a vacuum, but still no luck. It's a mystery to me!

[Big-Bird]

What temp is that new thermostat rated for?

A few extra degrees over a stock Delica thermostat can cause this problem because it allows the engine to run hotter...

Mardy from Amazing Auto posted something just recently on this very subject only last week. There are Pajero thermostats that will fit a Delica but the Pajero uses a slightly higher temperature rating.
The radiators between a Pajero and Delica are also slightly different as some people on this forum can certainly confirm which would lead me to think your 'stat 'is the source of the issue.

The only other thing is there might be air in the system. I have an L400 and there is a bleed screw for entrapped air at the heater core inlet just above my batteries.

If you have an L300 I am not sure where its located....anyone care to offer some input?

There is only one other possibility: something is preventing/blocking the flow of air through the rad. Either a weak clutch fan or dust/mud have built up on the cooling fins of the radiator.

I recently replaced the rad in my L400 and there was a paperbag between the rad and the a/c evaporator. My temps have dropped by 1/3 since that fix.