Coolant Bleeding of the Diesel - Yet Another Perspective

[Bongo nads]

bongonads

[mister munkey]

Answer: The elbow from the head, with the turbo coolant port, does not also have a blead port.

Thats a Ranger head I belieive, no rear aircon in the Ranger lump so no need for the bleed pipe.

Good fix by the way but a compatible 3 way converter block is available if you search hard enough.

[Bongo nads]

bongonads

[Bongo nads]

bongonads

[rita]

New slant on an old issue. And an alternative way of bleeding the cooling system emerges.

I’m in New Zealand. I’m a 60-y-o with the same love of getting my head under a car bonnet that I had when I was 18, but I’m not a mechanic.

I bought a good diesel “Mazda Freda” (registered on import into NZ in that name) with low Kms for a song. It had been taken as a trade by a small caryard who hadn’t picked up that the vehicle had head issues, and the dealer was in turn having to sell it in “as is” condition.

I took the head off. It was cracked. But that was okay ‘cos I had another head. Put the new head on never having realised that the head was not one from a Freda/Friendee, but some other WL-T. Does anyone know what the one difference is that distinguishes the Freda/Friendee head?

Answer: The elbow from the head, with the turbo coolant port, does not also have a bleed port.

I simply hadn't noticed the difference until all the work had been done, and it was time to connect the bleed hose. Oh dear, what to do. when filling the coolant mix? I filled the coolant system using the usual thermostat-opening routine. But that meant airlocks in the engine block and head.

I sat there in my living room for two nights, with the cracked head on my coffee table me studying it during the TV ad breaks, when suddenly I had an answer.

I put the front wheels of the vehicle higher by a few centimetres than the rear wheels. With a 12mm socket (long socket) I undid the temperature sensor at the front right of the head next to the front end of the intake manifold (pics to follow). I dipped a wooden ice-cream stick down about 65mm into the sensor hole. Bone dry!

I waited and watched. And about ten minutes later, slowly the green-tinged coolant rose up and gently overflowed out of the hole. I refitted the sensor. And voila. I had airlocks no more.

Footnote: I have been absolutely amazed at the extent to which mechanics of years of experience have NO IDEA whatsoever of what this issue is all about. And even when it is explained to some very well qualified mechanical minds, they still simply don’t get it, that having coolant top pipes running under the floor, means things are a bit different to the usual. Only when one compares it to bleeding brakes. do these geniuses start to see it.

Well done. Is this now the Bongo nads Method..

[missfixit70]

Well done for finding an alternative & I agree with you, the rear aircon makes no difference to the bleeding process, it's all about the rad hoses going so low. I can say this for sure having removed my rear heater & blanked the pipes off, no difference to the bleeding process & very little difference to the capacity of the system (about 600ml from memory, that includes the hoses, pipes & matrix removed).
The cross docking stock can be removed from the old head & put on the ranger head, but as you have no need for it, I wouldn't bother.
What about the air that gets trapped under the closed stat on the rad return bottom hose when you refill the system?

[Alacrity]

The stat should have a bleed hole in it to stop air trapping.

Vacuum bleeding answers all. Simple & quick, although not available to all. Why anyone with basic garage facilities (i.e. compressor) who does this sort of thing fairly often doesn't have one is beyond me I'm afraid.

[rita]

The stat should have a bleed hole in it to stop air trapping.

Vacuum bleeding answers all. Simple & quick, although not available to all. Why anyone with basic garage facilities (i.e. compressor) who does this sort of thing fairly often doesn't have one is beyond me I'm afraid.

The stat should have a bleed hole in it to stop air trapping.

That is probably the reason it takes about 10 minutes for the coolant to come through.The Jiggle pin.

[missfixit70]

The stat should have a bleed hole in it to stop air trapping.

Vacuum bleeding answers all. Simple & quick, although not available to all. Why anyone with basic garage facilities (i.e. compressor) who does this sort of thing fairly often doesn't have one is beyond me I'm afraid.

Because most home type compressors probably don't have the air delivery capable of doing it properly, a few people have done it succesfully, a few have still had to bleed it afterwards, bit hit & miss to me, i know where I am with bleeding, it allows me to check that things are happening as they should.
If the jiggle pin lets all the air through from the bottom hose, then how come there's a burp of air as the stat opens?

[Bongo nads]

bongonads

[dave_aber]

Alacrity, how about a thread on the topic "Cooling System - Vacuum Filling", cos it's just slightly off this topic.

Altenatively, just use this one -> http://www.igmaynard.co.uk/bongo/forum/ ... it=+vacuum

[Bongo nads]

bongonads

[dave_aber]

It is, however the principle of evacuating all the air before filling the coolant is the same whatever device you use to create the vacuum. The MG/Rover forum describes the principle quite well. (And in that thread, I mentioned that the pela vac refill method would be a good starting point, followed by a convertional bleed to be sure)

The end of that thread is a posting by Alacrity where he is talking about using the snap-on kit, which uses a compresser to create the vacuum. Laser do one as well (£72 @ Halfrauds), toolshop direct do one for £62, Abbey Tools do the same one for £59, and Sealey do one for £65.

As far as I can see, the only downside of the pela system is that you can't tell what level of vac you have created without a vac gague. I'll certainly be giving it a go as and when I change my coolant.

However, I'll also be looking at the sensor position you have highlighted as well. Presumably, you have blanked your EGR at the turbo side, and removed all the pipework, making the sensor more accessible?

[Bongo nads]

bongonads