Going to lose my mind soon! OVERHEATING issue but bled?!

[Alacrity]

If you have access to compressed air & can get hold of a vacuum coolant filler that will a) tell you if you have a leak (you won't be able to pull & hold a proper vacuum) & b) allow you to fill the system in a matter of minutes. They really do make it sooo simple to fill a Bongo cooling system, not much use though if you don't have any compressed air!

[timmyt]

The Voice Of Experience (I'm on my 3rd head now) agrees that the head has gone. Most likely a crack in the pre-combustion chamber in either No2 or No3 pot.

Steel Seal or something similar might give a short term reprieve but in the Real World you need to start thinking about finding around £1500 for a proper fix.

Its possible to get it done for half the money but scrimping on parts or the wisdom of an experienced spannerman tends to cost more in the long run.

Sorry to potentially bear nasty news, but life throws these curved balls at us from time to time. How you deal with it will make all the difference.

Sounds like you have had the short end of the straw (3 times!) there
Happy to carry the work out myself and confident in my spanner wielding ability and lucky enough to have access to lots of backup experience from work colleagues (marine engineers) and of course you guys on this forum.Just a big believer in doing exactly what im doing now,ASKING questions first!Before i make a royal c**k up!
Any suggestions on suppliers of heads,gaskets etc?
Seen varying prices,some sets twice the price of others,guess that says it all on quality righ?

[timmyt]

If you have access to compressed air & can get hold of a vacuum coolant filler that will a) tell you if you have a leak (you won't be able to pull & hold a proper vacuum) & b) allow you to fill the system in a matter of minutes. They really do make it sooo simple to fill a Bongo cooling system, not much use though if you don't have any compressed air!

No problem getting the compressed air...just need to find a vacuum filler now!!
Do they eliminate the need for the whole bleeding process on a bongo??? and really work??!!!!

[Northern Bongolow]

before you rip it to bits try as kirsty says,pressurise the system and look for obvious leaks.
pressureise it to at least a bar,but not much more as you will blow your core plugs.

the cooling system when normal but very hot and well worked can get to 12-13 pounds,which is very near the cap blow off point of 1.1 bar, so test the cap is good/or renew. 25% of the caps i test fail.

it sounds like the initial bleed was not correct,what method did you use,it could just have been an air pocket trapped somewhere that whilst resting migrated to the head, then when restarted it just got super hot(the fans kicked in).

i would suggest a good bleed then fit a pressure monitoring gauge to the expansion cap and see what pressures you get from inside the system.
the normal pressures for a healthy bongo are normal running 0.5 bar. hardish working= 10 pounds. fans on point= 96deg c is 12-13 pounds.

[timmyt]

Do you really think i may just have a trapped air pocket??
Suppose i have nothing to loose by re-checking all pipes etc AGAIN!
Me and the bongo are very much having a love hate relationship at the moment!and my girlfriend is nearly in tears at the thought of her being poorly!
And you know what,all this started after we talked about changing her for something bigger!..Herbie comes to mind!

[timmyt]

also has anyone tries the pela pump type coolant filling system as some MG owners have?
Any success?

[PixieAndTheMoon]

[/quote]Me and the bongo are very much having a love hate relationship at the moment!and my girlfriend is nearly in tears at the thought of her being poorly!
And you know what,all this started after we talked about changing her for something bigger!..Herbie comes to mind![/quote]

Bad stuff for you friend...

My Chris talked about getting something bigger, I was filled with dread, till he said I can sell up my car and keep her for a run around. I secretly thought about running off into the sunset, just me..... LOL

Hope you get sorted easily mate

Jo

[Northern Bongolow]

Do you really think i may just have a trapped air pocket??
Suppose i have nothing to loose by re-checking all pipes etc AGAIN!
Me and the bongo are very much having a love hate relationship at the moment!and my girlfriend is nearly in tears at the thought of her being poorly!
And you know what,all this started after we talked about changing her for something bigger!..Herbie comes to mind!

without you saying which bleed method you are using its hard to say if its just air,and its easier to help if you could give as much info as poss.this system is much misunderstood,but once you get it, it is fairly straight forward.
it is so easy to think the worst,but more often than not in the early stages it can be something silly,but as it gets overlooked it developes further.
start at the begining,check everything,you may just suprise yourself, and your wallet.

[Alacrity]

No problem getting the compressed air...just need to find a vacuum filler now!!
Do they eliminate the need for the whole bleeding process on a bongo??? and really work??!!!!

Yup. All I do is just vent the bleed pipe afterwards - & you will only get the tiniest hint of air out before the coolant. I have done mine twice now with no issues & my previous Freda twice, again with no issues. It really is simple to do. My cooling system works fairly hard as I don't pussyfoot around & most of my driving in it is towing boats.
The one problem you can have is getting it to pull & hold a vacuum, if you can't it can be a pain to find the leak, pressure would be easier in this instance.

[timmyt]

Hi all,quick update.
Pressure tester is currently on van as we speak,had it at 0.5 bar for half hour,no pressure drop
Increased to 13 lb and left it to see if it moves....no signs of any leaks from any hose/pipe,all hoses are rock hard.
So if pressure test comes back fine what next??!
I have a compression tester here and will test each chamber shortly...being lazy now but does anyone know what reading should come out of each cylinder on average,what are the accepted variables??
Regards
Chris

[Northern Bongolow]

do a pressure test in reverse, if you get what i mean.
fit the gauge then carefully run the engine up towards its normal temps and see what pressures your getting when warm and hot.
keep a close eye on things though if it raises quickly and cannot vent it could pop something.

compression test should normally speak for itself,just look for the odd one/two, as the head usually fails at a valve seat it should show up.

[timmyt]

do a pressure test in reverse, if you get what i mean.
fit the gauge then carefully run the engine up towards its normal temps and see what pressures your getting when warm and hot.
keep a close eye on things though if it raises quickly and cannot vent it could pop something.

compression test should normally speak for itself,just look for the odd one/two, as the head usually fails at a valve seat it should show up.

Thanks for that,will post back with results asap....here is hoping for good news for once!

[timmyt]

Ok,
Pressure test complete,no loss of pressure with COLD engine at 13 lb.left for over half hour.
Compression test complete...

Cylinder one - 20 lb
Cylinder two - 22 lb
Cylinder three - 20lb
Cylinder four - 20lb

So,what do you all think? Cylinder head ok??

As for the bleed method...i didnt do quite as is reccomended...instead of using a funnel i had a 5ltr drum of coolant with the bleed hose submereged,careful never to allow it to raise above the level of the water and never allowed the header tank to empty.i opened the heater vents...Seemed to expell all the air,had the bottom hose hot,hot air coming out of heaters and had a successful test drive uo and down hills,then as i said i came to fit new belts and it overheated!!!
Could it have been a air lock that migrated to the head after cooling down/being left to stand for few days?

Have arranged for a vacuum bleeder to be delivered as reccomended,will re-bleed system with that and see how i go.

Would it be worth puting steel seal in as a precaution maybe??

[missfixit70]

Hi all,quick update.
Pressure tester is currently on van as we speak,had it at 0.5 bar for half hour,no pressure drop
Increased to 13 lb and left it to see if it moves....no signs of any leaks from any hose/pipe,all hoses are rock hard.
So if pressure test comes back fine what next??!
I have a compression tester here and will test each chamber shortly...being lazy now but does anyone know what reading should come out of each cylinder on average,what are the accepted variables??
Regards
Chris

Unfortunately, the fact you've found no leaks, probably means that if you had bled it properly, there is a crack/leak that is opening up when the engine is warm.

[timmyt]

Hi all,quick update.
Pressure tester is currently on van as we speak,had it at 0.5 bar for half hour,no pressure drop
Increased to 13 lb and left it to see if it moves....no signs of any leaks from any hose/pipe,all hoses are rock hard.
So if pressure test comes back fine what next??!
I have a compression tester here and will test each chamber shortly...being lazy now but does anyone know what reading should come out of each cylinder on average,what are the accepted variables??
Regards
Chris

Unfortunately, the fact you've found no leaks, probably means that if you had bled it properly, there is a crack/leak that is opening up when the engine is warm.

Strange thing is,after replacing the burst pipe originally,bleeding etc we drove around for 3 days with no probs,then she just started overheating with no leaks found!


Should i try bringing the van up to temp with the pressure tester connected?