Air Lock? considering removing the stat....

Technical questions and answers about the Mazda Bongo

Moderators: Doone, westonwarrior

stevedon
Bongonaut
Posts: 80
Joined: Sun Jun 14, 2009 8:42 am
Location: New Zealand

Re: Air Lock? considering removing the stat....

Post by stevedon » Sat Oct 24, 2009 5:05 am

if your bottom hose is not getting warm/hot the thermostat is not opening ,go get a new one genuine is best. toflush the rad properly you need to take it out and give it to a rad specialist who can clean out each of the rows. .
Hot water is hheated up by the head and block and as the thermo opens (84deg) the water flows into the rad and then cooler water enters the head .
get a new thermo they are pennies
User avatar
haydn callow
Supreme Being
Posts: 5772
Joined: Mon Jan 08, 2007 9:50 pm
Location: Somerset
Contact:

Re: Air Lock? considering removing the stat....

Post by haydn callow » Sat Oct 24, 2009 9:02 am

Ok. I have just flushed through the rad....seems there is no blockage.
Taken the stat out (again!) and tested it and it opens fine when heated up in a saucepan.
Flushed through from the top hose through to the bleed pipe..seems to be no problem there.
http://www.coolantalarm.co.uk
Developer of the Mazda Bongo Coolant loss Alarm
Also BMW Clocks
Aunt Trumpet

Re: Air Lock? considering removing the stat....

Post by Aunt Trumpet » Mon Oct 26, 2009 12:24 pm

UPDATE.....I think I might have a go at this Steel Seal stuff....surely its got to worth a punt at £30 don't you think?....

Seems to be working for "bikemonkey"....in his thread...( don't know how to link it.... :oops: )
User avatar
mikexgough
Supreme Being
Posts: 6158
Joined: Mon Sep 08, 2008 9:02 pm
Location: Cambridgeshire - where the all the Slodgers reside
Contact:

Re: Air Lock? considering removing the stat....

Post by mikexgough » Mon Oct 26, 2009 12:34 pm

if you use Steel Seal.... make sure you have the stat in place, best with a new 'un so the cooling system is in the "default" state as if it works you wont need to "break" open the system again..... While not being a believer in these treatments, I have seen the results and read on here how it worked on a Bongo........... how long the fix remains is anyone's guess and what happens after a future coolant change?..... good luck with whatever you decide on
Conversant with Bongo Top Pinion Oil Seals

Bongo owning Velotech Cycle Mechanic
Aunt Trumpet

Re: Air Lock? considering removing the stat....

Post by Aunt Trumpet » Mon Oct 26, 2009 2:26 pm

if you use Steel Seal.... make sure you have the stat in place, best with a new 'un so the cooling system is in the "default" state as if it works you wont need to "break" open the system again..... While not being a believer in these treatments, I have seen the results and read on here how it worked on a Bongo........... how long the fix remains is anyone's guess and what happens after a future coolant change?..... good luck with whatever you decide on
Thanks mate, if I'm honest I'm sceptical too and i'm not too hopeful, but if it works great....if not never mind. I'll post up honest findings on here whatever the outcome so then others can make their own judgements

I was wondering as to wether to apply it with the stat out so it gets all around the system but as you say I'll do it with the stat in and do exactly what it says on the box. I've looked at the instructions online and I was wondering if I might have to merge the Bongo bleeding practices with the product instuctions.
Aethelric
Bongolier
Posts: 418
Joined: Mon Feb 25, 2008 3:50 pm
Location: Fife
Contact:

Re: Air Lock? considering removing the stat....

Post by Aethelric » Wed Nov 04, 2009 2:11 pm

haydn callow wrote:I think the issue is becoming confused....Bleed the system when cold ??? surely we are doing that every time we are waiting for the stat to open....
Sorry about the delay to replying to this - I'm snowed under just now. But here is the logic of a cold bleed.

When you do a normal bleed you should get all of the air out of the system. But what you don't know is if any air is being introduced slowly into the system. With a bongo, if the air gets into the head, it won't come out by itself.
It may be a small amount - maybe only 1cc per mile travelled. But 1000 miles after a normal bleed you would have a litre of air trapped in the head and this is probably more thyan enough to cause overheating and damage.
The one thing you ARE sure about though is that it won't collect behind the stat. So a quick check, being very careful to keep the bleed hose submerged in coolant (easy if its cool or lukewarm) will quickly reveal if you have air in the head, and expel it.
If you regularly get air out you have a problem. If its only a small amount then regular cold bleeds will keep the bongo safe until you get it fixed.
I think it would definitely be a good thing to do after you get a bongo back from a garage too.

Dave
antb

Re: Air Lock? considering removing the stat....

Post by antb » Thu Feb 23, 2012 1:39 pm

Hi Aunt - I'm keen to know what happened - so did you fix the problem with steel seal or have to replace the head/head gasket?
Thanks,
Ant
User avatar
dandywarhol
Supreme Being
Posts: 5446
Joined: Mon Dec 19, 2005 10:18 pm
Location: Edinburgh

Re: Air Lock? considering removing the stat....

Post by dandywarhol » Thu Feb 23, 2012 2:00 pm

Aethelric wrote:
haydn callow wrote:I think the issue is becoming confused....Bleed the system when cold ??? surely we are doing that every time we are waiting for the stat to open....
Sorry about the delay to replying to this - I'm snowed under just now. But here is the logic of a cold bleed.

When you do a normal bleed you should get all of the air out of the system. But what you don't know is if any air is being introduced slowly into the system. With a bongo, if the air gets into the head, it won't come out by itself.
It may be a small amount - maybe only 1cc per mile travelled. But 1000 miles after a normal bleed you would have a litre of air trapped in the head and this is probably more thyan enough to cause overheating and damage.
The one thing you ARE sure about though is that it won't collect behind the stat. So a quick check, being very careful to keep the bleed hose submerged in coolant (easy if its cool or lukewarm) will quickly reveal if you have air in the head, and expel it.
If you regularly get air out you have a problem. If its only a small amount then regular cold bleeds will keep the bongo safe until you get it fixed.
I think it would definitely be a good thing to do after you get a bongo back from a garage too.

Dave
It can collect and pass through the stat if it has a air bleed jiggle pin like this one..................................

http://www.igmaynard.co.uk/bongo/Forum/ ... p?p=144206
Whale oil beef hooked
Renault Lunar Telstar
Yamaha TD1C 250, Merc SLK200, KTM Duke 690
Post Reply

Return to “Techie Stuff”