Overheated, low coolant, advice.

[bigdaddycain]

I haven't got a manual, is that the same method that mazda dealers used in japan?

[bigdaddycain]

So in that case Ste, does the manual show the bleedpipe HIGHER than the head and expansion tank?

The pic shows the bleeder pipe hanging from the steering wheel spoke - to get the pipe to the highest point. That way ALL the air is forced out IMO.

You can't expel ALL the air initially Alan.

[dandywarhol]

I reckon your asking for trouble having the bleed pipe lower than the highest part of the cooling system when it's open and trying to expel the air. and if folks are doing this then thats why it takes them so long to bleed it properly.

I've only bled the system EXACTLY as the clever guys in Japan suggest and have never had a problem with airlocking.

Just last night I emailed Ian to amend the factsheet because I think there's a serious omission in the factsheet about the position of the bleedpipe. This misinformation could cause a serious airlock IMO. The factsheet only says to have the pipe positioned downwards - bad info IMO - it should be pointing downwards (to avoid scalding - H & S and all that) but HIGHER than the engine.

[bigdaddycain]

I don't understand? If the bleedhose is held up the coolant stops coming out of the end of the bleedhose.

The coolant isn't suspended in mid air inside the pipe, it's making it's way back down the bleedhose,where it will firstly encounter the cylinder head, if the pipe aint filled with coolant, it's filled with air.

Surely peeps aren't bunging the bleedhose in the upwards position whilst its full of air, not coolant?

I don't pretend to have any mechanical or engineering background Ian, but i do know how gravity works bud!

I agree about "those clever chaps in japan" though, they certainly knew how to extract the equivelant of £100 from punters for the bi-annual coolant change,knowing that the warranty would be void if it wasn't carried out, or if anybody other than a mazda/ford garage attempted to bleed the system....

That would account for the overly complicated (in many peoples opinion) official bleeding technique.

I wonder how many mazda techies actually bled the sytem?

[dandywarhol]

If the bleedhose is at the highest part of the cooling system then as long as there's a continual flow of coolant coming out of it with the engine running then there's no air anywhere else. That's then the plug should be put into the pipe and the jobs done IMO.

[bigdaddycain]

If the bleedhose is at the highest part of the cooling system then as long as there's a continual flow of coolant coming out of it with the engine running then there's no air anywhere else. That's then the plug should be put into the pipe and the jobs done IMO.

I have bled a few bongo's, each time i have done it, holding the bleedhose up stops the coolant from coming out of the bleedhose.

[dandywarhol]

As long as it works for you Ste - I've just gone with the manual - seems daft to reinvent the wheel, and it works fine for me - the coolant soon goes up the small bore bleed pipe when all the airs out and the pump is helping it when the 'stats open.

[bigdaddycain]

Yep, understood alan, i wasn't endeavouring to devise a superior method mate, if truth be told, i didn't fully understand the official method,and thought it a little over-complicated.

That's why i came up with my own.

Mike at wheelquick uses a slight variation on the hosepipe method too alan, just by chance, i employed my own method before i'd even heard of wheelquick.

Different routes, same goal.

[Peg leg Pete]

I must admit that I extend and raise the bleedhose when I have done a coolant change, it helps to expel trapped air You do have to be careful though as the air does expel at a good rate

[bigdaddycain]

Different routes, same goal.

[Peg leg Pete]

I agree steve

[haydn callow]

I have bled our Bongo at least 6 times and 3 or 4 times for other peeps. As far as I know...none of them had the level drop overnight or needed topping up. Therefore ALL the air must have been bled during the process. I use the See Saw method as shown to me by Alan at Plymouth.

[bigdaddycain]

I agree steve

Thanks pete, did you use the see-saw method?

[dandywarhol]

I'm not saying the see saw method doesn't work - any method which works has to be applauded. However, what I am saying is that the factsheet has an extract from the manual and it needs to be ammended before someone does cook their engine because of misinformation.

[bigdaddycain]

The in's and out's of the other methods have slipped my mind alan... Does the see-saw method differ from the method in the manual?