Coolant Pressure..

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chiefster1976
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Coolant Pressure..

Post by chiefster1976 » Mon Sep 24, 2012 11:47 am

Hi all.. Just had a pre inspection test on the bongo before i sell it and apparently its slightly loosing pressure'
15 down to 13.5..(im guessing its in psi) Is this alot??
Ha the coolant changed recently, the machanic didnt do the funnel in the air bleeding type procedure shown on you tube,
not sure what he did...
No sign of leaks anywhere, coolant at minimum level and no overheating at all...No oil in coolant etc..
Any advice on this.. just wondering if i need to get it re bled or something...Hopeing its not a head gasket...???
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Driver+Passengers
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Re: Coolant Pressure..

Post by Driver+Passengers » Mon Sep 24, 2012 12:02 pm

Under what conditions and how were the 15 and 13 values obtained? "Normal" running pressure is 10-13 psi, I believe. Header tank cap is designed to relieve pressure when it reaches 1.1 bar (16psi). Pressure will drop as the engine/coolant cools down.

Need a bit more info from you first, I think...
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Re: Coolant Pressure..

Post by Northern Bongolow » Tue Sep 25, 2012 12:31 am

and how long was the test done for, as mat rightly says the coolant temp will gradually fall (and the pressure) after its been ran then allowed to cool.
over here in shivery britain the coolant pressure will fall to zero(ish) in a few hours from the normal running pressure of around 10 psi.

top tip.
if you think you may have a leak----------- you usually have a leak, but it may just be hard to find.
chiefster1976
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Re: Coolant Pressure..

Post by chiefster1976 » Tue Sep 25, 2012 8:36 am

Thanks for your replies thus far...
The van was COLD and NOT running.. the Guy stuck his pressure tester onto the coolant fill and pumped the pressure and i guess took the 15 reading there...

Then left the vehicle NOT RUNNING for about 6-10 mins and then looked at it again and and said its lossing pressure to 13.5..
Does the vehicle have to be running??
I was under the impression this mobile Purchase inspection guy should know how to check properly...

The coolant has just been changed..It was quite low but not low enough to take in air i think...Just topped it up tonight..

A mate at work said a good way to get rid of air is to park on a steep hill with the nose in the air with cap off but engine not running..That will get ride of air bubbles.. Duno myself lol..

Buyer is still keen to buy just concerned with the report on coolant pressure.. Just want it to be right for my buyer..
Any ideas and correct procedures would be helpful thanks... maybe i can buy a pressure tester myself/./
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Driver+Passengers
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Re: Coolant Pressure..

Post by Driver+Passengers » Tue Sep 25, 2012 8:56 am

OK, a cold pressure test. I've been messing with measuring dynamic pressure while running, so that's what distracted me.

1.5 psi over 5-10 minutes is measurable, but you've also introduced two new parts into the system, cap seal and gauge. Hard to say. There are UV additives that you could try - put in the coolant, run the van to circulate. Let it go cold. Pressure it up as before, give it 10 minutes and then crawl around underneath with a blacklight.

Alternatively, on the coldest day you can find, with a stone cold van, get the undertray off, and put cardboard/newspaper underneath to catch/show any drips. You might be pushing it. UV method is going to be more reliable.
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Re: Coolant Pressure..

Post by dandemann8 » Tue Sep 25, 2012 9:02 am

Driver+Passengers wrote:OK, a cold pressure test. I've been messing with measuring dynamic pressure while running, so that's what distracted me.

1.5 psi over 5-10 minutes is measurable, but you've also introduced two new parts into the system, cap seal and gauge. Hard to say. There are UV additives that you could try - put in the coolant, run the van to circulate. Let it go cold. Pressure it up as before, give it 10 minutes and then crawl around underneath with a blacklight.

Alternatively, on the coldest day you can find, with a stone cold van, get the undertray off, and put cardboard/newspaper underneath to catch/show any drips. You might be pushing it. UV method is going to be more reliable.
They don't have cold days in Queensland, well they didn't when I was there :lol: :lol: :lol:
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Re: Coolant Pressure..

Post by Driver+Passengers » Tue Sep 25, 2012 9:28 am

dandemann8 wrote:
Driver+Passengers wrote:Alternatively, on the coldest day you can find, with a stone cold van, get the undertray off, and put cardboard/newspaper underneath to catch/show any drips. You might be pushing it. UV method is going to be more reliable.
They don't have cold days in Queensland, well they didn't when I was there :lol: :lol: :lol:
By contrast, with our weather, we are spoilt! :? :lol:
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chiefster1976
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Re: Coolant Pressure..

Post by chiefster1976 » Tue Sep 25, 2012 10:36 am

So in Laymans terms a cold pressure test he used is unreliable when using a pressure gauge on the coolant expansion tank???
No visable signs of leaks anywhere..

UV additives will have to ask around there but dont fancy my chances.. Carnt even get front brake discs or front rear lower wishbone bushes over here in OZ, im possitive Oz is 10 years behind Europe in products and services..Its annoying..

Its spring here, 25-29 degree days..pleasant at the moment but the humidity on summer is past 90%. Spring is the best..
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Re: Coolant Pressure..

Post by Driver+Passengers » Tue Sep 25, 2012 11:09 am

chiefster1976 wrote:So in Laymans terms a cold pressure test he used is unreliable when using a pressure gauge on the coolant expansion tank???
No visable signs of leaks anywhere..
Not necessarily, I think it's standard practice. Just worth a double check that the unit itself and it's seal is sound, etc... I guess another close inspection of common failure points wouldn't hurt. But I'm not sure I can add much more.

I think there was a bulk buy of UV additive over here a few years back. Perhaps someone has access to an amount...

Good luck.
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Re: Coolant Pressure..

Post by MountainGoat » Tue Sep 25, 2012 11:34 am

That was Haydn Callow who made the bulk purchase and sold it off the stuff to members. There may be an odd chance that someone still has some unused dye in their garage that they don't need any more. Always worth asking in the wanted section.

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Re: Coolant Pressure..

Post by Northern Bongolow » Tue Sep 25, 2012 7:54 pm

the red coolants we have here have the uv tracer in them (apparently), not tested this myself though. may be an idea to look into the red coolants over there.
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Re: Coolant Pressure..

Post by mikexgough » Thu Sep 27, 2012 4:56 pm

http://www.nulon.com.au/products/Coolin ... GR2eLJlSZc

Yep.... Premium Car Plan Red et al coolant has a dye in it plus is borate,sulphate,phosphate free chemistry as the Bongo had in the factory... the Nulon coolant is supposed to be top notch...
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chiefster1976
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Re: Coolant Pressure..

Post by chiefster1976 » Thu Oct 04, 2012 9:13 am

I took a look at the youtube bongo fury coolant procedure... they mention keep topping up the coolant as its being bled(at the engine bay area bleed pipe) but they dont mention wether if the coolant will over flow at all in the expension tank when hot!!

I left my expansion tank cap off whilst running the bongo and the coolant just overflowed...Is this a sign of lossing pressure/head gasket problem or just the fact that it will overflow if you dont have the funnel at the bleed pipe area and use the method in the video??
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Re: Coolant Pressure..

Post by Velocette » Thu Oct 04, 2012 9:53 am

chiefster1976 wrote:I took a look at the youtube bongo fury coolant procedure... they mention keep topping up the coolant as its being bled(at the engine bay area bleed pipe) but they dont mention wether if the coolant will over flow at all in the expension tank when hot!!

I left my expansion tank cap off whilst running the bongo and the coolant just overflowed...Is this a sign of lossing pressure/head gasket problem or just the fact that it will overflow if you dont have the funnel at the bleed pipe area and use the method in the video??
I would say it was normal for the coolant to overflow due to expansion when the engine is run up to temperature if the level was correct when cold. The reason it doesn't necessarily overflow during bleeding, I guess, is that it is not completely full and will need topping up when it cools. I haven't done a bleed, I am just going on the videos and my ancient schooldays physics :). Also with the pressure cap in place the boiling point of the liquid is higher although I have only seen my Bongo reach 100 once or twice, in mountain areas. Without a pressure cap it would have boiled on those occasions.
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Re: Coolant Pressure..

Post by Northern Bongolow » Thu Oct 04, 2012 1:25 pm

chiefster1976 wrote:I took a look at the youtube bongo fury coolant procedure... they mention keep topping up the coolant as its being bled(at the engine bay area bleed pipe) but they dont mention wether if the coolant will over flow at all in the expension tank when hot!!

I left my expansion tank cap off whilst running the bongo and the coolant just overflowed...Is this a sign of lossing pressure/head gasket problem or just the fact that it will overflow if you dont have the funnel at the bleed pipe area and use the method in the video??
i dont understand what you are saying here :oops: . can you make it clearer.
are you asking if the coolant should come out of the expansion tank when running if the bleed bung is still fitted.
if using the seesaw method with a funnel attached the air is removed from the system so you need to replace this lost air with coolant to totally fill the system.
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