Vacuum filling coolant

[parawaiting]

I am about to do a coolant change before a European trip and had a few questions which I haven't found answers for or aren't covered in the factsheet
1/ I was going to draw a coolant mixture up through the bleed pipe from bottom to top by applying a vaccum to the header tank, has anyone done it this way and is there any reason why I shouldn't
2/ if there are any airlocks in the system how do you find out? other than by having overheating problems
3/I can't find many references to actually draining the old coolant in the factsheet, is this done with a cold ehgine and once you undo the bleed pipe will it all discharge??
all answers appreciated


cheers

paul

[haydn callow]

You need to drain the coolant by using the tap (bottom drivers side of RAD ) even better if you are doing a proper job also remove a rear heater hose,
Vacuum filling as described may work....I wouldn't personally use it....But what you MUST do is at some point get that bottom hose hot to ensure the stat is open..
You can drain hot or cold.
Good idea to fit a new MAZDA stat whilst your about it and "flush" the system

[nfn]

Sounds like a plan -- but to be safe, afterwards you should bleed using one of the proven methods (see factsheet).

I bought a Sealey coolant filler a while back which uses a vacuum. I was hoping it would be an amazing tool, but it saves no time: in the time it takes to wheel out the compressor, connect the filling tool up, check for air leaks, fill a suitable large container with coolant, then find a stable spot to put the bucket of coolant, you could have filled and bled the normal way.

In principle what you are doing should work as long as the thermostat doesn't trap air behind it. I use a vacuum applied at the wheel cylinder with a Pela pump connected to rubber tubing to bleed brakes. It works a treat.

I don't know the answer to your last question -- the Bongo has no coolant drain plug on the bottom of the block, and it is difficult to remove all of the coolant without removing several hoses to spray water through to flush.

Let us know how you get on.

[Alacrity]

I have always filled (well the 2 times I have done it) both my Bongo's using a vacuum filler. I am in the trade so the compressor is always there but it has always proved a simple & easy way to fill in my experience. Since I changed my rad in January the re-filled it using vacuum the beast has done many trips including an 1100 mile round trip towing all the way. Not had a problem. They were invented for systems that are prone to airlocking to get around the problem.

[parawaiting]

as we are due to leave next friday, may or may not do it depending on how much time I have,
Is there a diagram of the cooling system on lush projects for example??

cheers



Paul

[missfixit70]

Here's a list of the lushprojects drawings that show the cooling/heating system, not all on one diagram unfortunately

Complete list of hoses

Main cooling system - http://www.lushprojects.com/bongopartsm ... mgno=.html

15-261 - bypass/recirc into top of thermostat
15-381 - bleed hose
15-186 - top hose/engine outlet to large metal pipe drivers side
15-183 - Large metal pipe drivers side to top of rad (inlet)
15-184 - bottom of rad/outlet passenger side to large metal pipe passy side
15-185 - passy side large metal pipe to bottom of thermostat
15-227 - top of rad to header/expansion tank
15-188 - expansion/header tank to heater return pipe

Most of front & rear heater system - http://www.lushprojects.com/bongopartsm ... mgno=.html

61-211 - drivers side heater pipe to front heater matrix
61-212 - front heater matrix to heater return pipe
61-214 - heater return pipe to thermostat
61-213 - outlet over starter on engine, drivers side to heater pipe
61-211A - drivers side heater supply pipe to rear heater matrix

Rear heater return - http://www.lushprojects.com/bongopartsm ... mgno=.html

61-212C - rear heater matrix to return pipe behind engine

Another rear heater return - http://www.lushprojects.com/bongopartsm ... 1of02.html

61-213A - rear heater return pipe connector behind turbo under passy seat

Two turbo cooling hoses - http://www.lushprojects.com/bongopartsm ... mgno=.html

13-539A &
13-546 - turbo suppply & return hoses

These threads - http://www.igmaynard.co.uk/bongo/forum/ ... =3&t=35902 -
http://www.igmaynard.co.uk/bongo/forum/ ... =3&t=36433 may be of interest if you want to know how it works, or check the factsheets in the members area.