Step by step coolant flush?

[SquamptonRyan]

Hello Delica land!

Just wondering if someone has a step by step of flushing the cooling system available. At one time I heard that there was a filter that was to be removed and cleaned in there somewhere. If I am wrong and there is no such filter, I can figure it out without instruction. More or less just wondering if there is any snags that I should be ready for.

Thanks, everyone have a delitastic day!

[Glenn Delwood]

I'd like to know that too. I thought I'd revive the question. Anyone?
Thank you.

[FalcoColumbarius]

Umm... Okay, but be forewarned that I'm talking about the Starwagon ~ but I'd imagine that the general principle would be the same.

This is what I do: I begin by removing the bottom steering skid pan (2x14mm, 4x12mm bolts); then I pull the draining hose out into the clear and strategically place an oil style catching pan (sans oil). I open the rad cap then open the drain cock at the bottom left, backside of radiator and drain. Next I fashion a piece of cardboard box as a shield to fit in behind the cooled down exhaust manifold. By this time the radiator has drained and I've moved the receptacle to under the rear right block area, under where the block coolant drain bolt is (I think it's 17mm). Incidentally, I've emptied the first lot of coolant from the rad out of the pan and into a twenty litre paint pail. With the receptacle pan under the block drain bolt I loosen the bolt off until I see a little bit of coolant seeping through; strategically place the custom crafted cardboard shield adjacent from the block drain so when I completely remove the bolt with my fingers ~ the gushing coolant leaping out of the block will reflect off the cardboard shield and down into the pan. Sometimes I'll also drain the rear cabin heater configuration but seeing as you want to flush then I'd not bother.

Having drained the rad and the block I replace the drain bolt in the block and close the stop cock in the radiator and fill the rad with fresh water and turn the engine on. The engine will need to warm up a little so the thermostat will open up (you need to be there watching). When the thermostat opens the level in the rad will drop and you need to add more water. I use a funnel with a control valve so I can add increments of water as the water level goes down. Fill until the water level stops going down ~ and hang around with the engine running for a bit as there will be air pockets that may not empty right away.

Although I have used Prestone radiator flush once ~ I'm concerned with how it might react with the aluminium engine head, but seeing as using water does pretty much the same thing (IMO) I don't bother. Also I leave the rad cap off all through this process.

Now as you two appear to drive a Saab and a Hilux... I'm going to presume that you both drive Space Gears. I have never done this to a Space Gear but I do understand that the Space Gear "rad cap" is located on the overflow bottle. Check the manual.

On my Starwagon, I will repeat the process, that is ~ let the motor cool down and drain the cooling system of water (like before) and refill it with more water and circulate it again.

After I'm satisfied that the system has been flushed I empty the water and prepare the new coolant. I run my mixture 40% glycol formula (anti-freeze) with 60% distilled water. I prefer this mixture because although the coolant has both anti-corrosive, lubricating and anti-freeze properties Water has more mass and therefore removes more heat. Besides, unless you're operating your vehicle up in the Arctic Circle you don't need a 50/50 mix, in my humble opinion.

Check in the relevant cooling system manual specs (found in the Dedicated Category Reference Forums) as to how much your particular system holds and mix accordingly. Most Delicas I know tend to use Mopar, however I have started using Hepu G11 coolant which is designed for the older VW aluminium head turbo diesels, which is similar to the Mitsubishi set-up ~ but you should always be careful as some coolant formulas are designed for specific engines with specific metallurgic combinations and the wrong coolant could have a galvanic reaction and eat your head.

Again, you need to make sure that you fill the whole system with coolant as air pockets can form, especially behind the thermostat, creating an air cushion around the paraffin wax activated valve, keeping the thermostat slightly cooler than the engine, which means the engine will run hotter. When you're satisfied that you've completely filled the system with the coolant mixture, put the cap on and go for a drive, take a few corners, climb a hill, go over a bumpy surface then check that your overflow bottle is still at the correct level (I usually shine a torch into the plastic bottle to establish the coolant level.

Some people will drill a 16th of an inch hole into the thermostat's upper plate to help alleviate any air pockets, could be a good idea, I've not done it but would be interested to hear from someone whom has.

Hope this helps... smiles.

Falco.

P.S.: If your coolant is relatively new and you're satisfied with the cooling performance then put the old stuff back in and save a few bucks. I've learned, however, that if your coolant is more than two years old then it's is a good time to replace it as anti-freeze does go stale, much like ATF or differential fluid. Take the old coolant to Canadian Tire for disposal. FC.

[Glenn Delwood]

Thank you Falco, I've missed this reply of yours. I was looking for an old post of mine where I thought I'd mention the alternator belt sizes. Mine, even though they are (were) new, due to mis-tightening them, got worn (the front one at least).

[Glenn Delwood]

Umm... Okay, but be forewarned that I'm talking about the Starwagon ~ but I'd imagine that the general principle would be the same.

This is what I do: I begin by removing the bottom steering skid pan (2x14mm, 4x12mm bolts); then I pull the draining hose out into the clear and strategically place an oil style catching pan (sans oil). I open the rad cap then open the drain cock at the bottom left, backside of radiator and drain. Next I fashion a piece of cardboard box as a shield to fit in behind the cooled down exhaust manifold. By this time the radiator has drained and I've moved the receptacle to under the rear right block area, under where the block coolant drain bolt is (I think it's 17mm). Incidentally, I've emptied the first lot of coolant from the rad out of the pan and into a twenty litre paint pail. With the receptacle pan under the block drain bolt I loosen the bolt off until I see a little bit of coolant seeping through; strategically place the custom crafted cardboard shield adjacent from the block drain so when I completely remove the bolt with my fingers ~ the gushing coolant leaping out of the block will reflect off the cardboard shield and down into the pan. Sometimes I'll also drain the rear cabin heater configuration but seeing as you want to flush then I'd not bother.

Having drained the rad and the block I replace the drain bolt in the block and close the stop cock in the radiator and fill the rad with fresh water and turn the engine on. The engine will need to warm up a little so the thermostat will open up (you need to be there watching). When the thermostat opens the level in the rad will drop and you need to add more water. I use a funnel with a control valve so I can add increments of water as the water level goes down. Fill until the water level stops going down ~ and hang around with the engine running for a bit as there will be air pockets that may not empty right away.

Although I have used Prestone radiator flush once ~ I'm concerned with how it might react with the aluminium engine head, but seeing as using water does pretty much the same thing (IMO) I don't bother. Also I leave the rad cap off all through this process.

Now as you two appear to drive a Saab and a Hilux... I'm going to presume that you both drive Space Gears. I have never done this to a Space Gear but I do understand that the Space Gear "rad cap" is located on the overflow bottle. Check the manual.

On my Starwagon, I will repeat the process, that is ~ let the motor cool down and drain the cooling system of water (like before) and refill it with more water and circulate it again.

After I'm satisfied that the system has been flushed I empty the water and prepare the new coolant. I run my mixture 40% glycol formula (anti-freeze) with 60% distilled water. I prefer this mixture because although the coolant has both anti-corrosive, lubricating and anti-freeze properties Water has more mass and therefore removes more heat. Besides, unless you're operating your vehicle up in the Arctic Circle you don't need a 50/50 mix, in my humble opinion.

Check in the relevant cooling system manual specs (found in the Dedicated Category Reference Forums) as to how much your particular system holds and mix accordingly. Most Delicas I know tend to use Mopar, however I have started using Hepu G11 coolant which is designed for the older VW aluminium head turbo diesels, which is similar to the Mitsubishi set-up ~ but you should always be careful as some coolant formulas are designed for specific engines with specific metallurgic combinations and the wrong coolant could have a galvanic reaction and eat your head.

Again, you need to make sure that you fill the whole system with coolant as air pockets can form, especially behind the thermostat, creating an air cushion around the paraffin wax activated valve, keeping the thermostat slightly cooler than the engine, which means the engine will run hotter. When you're satisfied that you've completely filled the system with the coolant mixture, put the cap on and go for a drive, take a few corners, climb a hill, go over a bumpy surface then check that your overflow bottle is still at the correct level (I usually shine a torch into the plastic bottle to establish the coolant level.

Some people will drill a 16th of an inch hole into the thermostat's upper plate to help alleviate any air pockets, could be a good idea, I've not done it but would be interested to hear from someone whom has.

Hope this helps... smiles.

Falco.

P.S.: If your coolant is relatively new and you're satisfied with the cooling performance then put the old stuff back in and save a few bucks. I've learned, however, that if your coolant is more than two years old then it's is a good time to replace it as anti-freeze does go stale, much like ATF or differential fluid. Take the old coolant to Canadian Tire for disposal. FC.

Getting ready to do this. I've had to do some work on the A/C rear unit which included draining coolant (from the rear heater core). I did take the entire box (I drive L400 besides the Saab) and I had the heater core flushed with water and pressurized air. Man it spit out a lot of mud! I'm convinced I need to do some of the same treatment to the entire cooling system. I got now a new water pump and new thermostat. I've never done it on another car so this will be a first. I'd like to drain and flush thoroughly. I've been reading in the online manuals and I'm a bit confused what the numbers on page 14-12 under "Water pump assembly installation" of the "PWEE9410_14_COOLING".pdf are. If anyone could shine some light I'd appreciate it. Also, it seems there are more plugs to open than simply a drain plug. I'm not sure I understood all but I'll do a bit more reading on it (although more insight would help).

Another thing is, how do I run pressured water through the entire system? (I'd like to really make sure it flows through all the pipes, head and hoses until it clears out all the crud.) The guys at the A/C shop said they'll flush it for me if I bring it with out a thermostat. Can I drive it without a thermostat? Is it ok to put cold water under pressure in the warm engine?

I'm sure I'll have more questions about the removal/installation of new thermostat and water pump but I'll have to do more homework. My 1999 Deville Manual is so much more detailed than the pdf. But then again, this is older stuff. I also do not have the DeVille anymore. :)
Thanks to all for the forum.

[thelazygreenfox]

Glen
Did you notice if your engine ran cooler with the rear heater core cleaned out?

I doubt you can run sufficient pressure through the entire cooling system to dramatically clean the system. I tried but nothing came out! Just like you claened your rear heater core you need to clean every component individually. Yup PITA!

I'm not big on changing water pumps unless they are leaking. Rather look for restrictions and unplug them for greater coolant flow.

The heater cores are often left plugged when pumps, thermostats and radiators are changed. Few garages clean/change cores. Heater cores remove lots of engine heat even when they're closed in the summer.
have fun
TLGF

[Glenn Delwood]

I didn't drive it at all after the heater core flush. I had the part out and just put it back in. I'll put water and drive it back to the AC shop to have the o-rings of the rear evaporator core replaced (it seemed the only spot where my AC was leaking) and have them flush it out a bit. I don't feel like taking every hose apart. I will swap my old and dirty expansion tank soon though.
I just took out the thermostat and it looks fine and clean. I wonder if I should change it at all. The manual says to "boil" it and measure the opening, etc. Might just do that before deciding.
Nothing else leaks and the temp gauge was always solid slightly below the middle. Don't have a pyro gauge (yet?).

[almac]

anyone ever use a rad flush kit on their delica?
it looks like it turns a messy job into a quick and simple job.
http://www.youtube.com/watch?v=tVWznOl-WZw