Overheating - Looking for troubleshooting steps

[Northern Bongolow]

Don't have the AC going when you bleed it as this will remove the heat from the front rad when the fans come in and out. you are trying to get it slowly warmed up and use the heater fans set too hot to feel for slight heat both back and front, then off, then check again several mins later, not Aircon, use the temp gauge to watch the heat slowly rise in the system, the secret is to build up the heat slowly.
Before the stat opens, gently rev the engine until the funnel is nearly empty, this will raise the temps,as you rev the funnel should empty, when the stat opens and you rev it, the funnels fills.
All these little indicators help you sense early that things are on track, a digital infa temp gauge can help as you know what temp the stat should open, and when the fans come on etc.

[surfkernow]

Thank you Mike and Northern Bongolow for the replies.

Mike - thank you for the tip on the heater radiator, I will look at that next.

Northern Bongolow - thank you. I have a Haydn Cylinder Head alarm so I am able to watch the temperature rise as I bleed the van. I did notice that the funnel stopped emptying at a certain point when I revved the engine, I see now that is when the thermostat opens.

The only thing I could think of today at work was the timing. The bleeding was going well, the thermostat had opened all bubbles pretty much gone, I was close to checking the lower radiator pipe and wrapping up. The front blowers were blowing warm air, so I had just switched them off to activate the rear heaters so could check if the rear heaters were blowing warm air.

It was only a minute after this or less I heard the gurgling at the front of the Van and realised all my coolant was on the ground and not in the expansion tank. I am wondering whether there is a problem or blockage in the rear heater matrix. I have read this is a common problem.

Thanks again for the replies, it is appreciated and maybe one day, if my problem is solved this thread will help other people. I am in contact with someone on FB who has the exact issue so we are comparing notes. His also overheated whilst bleeding "

[surfkernow]

Small update, i bled the van for an hour an a bit yesterday in a bid drive it to the garage. The van eventually bled ok, but as soon as I took it up the road it over pressurised and started to over heat.

One thing I noticed, which I had not seen before is steam emanating from area beneath the radiator. I took a video which is below. I had steam coming from the expansion tank and the funnel which is normal, but I noticed it emanating from beneath the radiator....is this normal?

The radiator is only a month or so old. The lower radiator pipe is not leaking...are there other coolant pipes in the area

https://youtu.be/k73f45263zs

[haydn callow]

Sounds like you need a new cyl head !!

[mikeonb4c]

About a year before my head cracked, my radiator went (seam between plastic top and metal matrix). A new one was fitted but it had a leak too (same place). So it can happen. Looking back I have wondered if the system was already beginning to overpressure and this could have exposed a weakness. Very firm top hose before engine warm is an indicator i think.

[surfkernow]

Thanks Haydn and Mike. I am hoping to get the Bongo to a local garage tomorrow to do some checks. The nearest is about 2 miles away. It will be 50/50 if makes it without over heating etc but I am going to go for it as it needs to be looked at. It will be a white knuckle ride trying to get it there.

Clarification. I talk a lot about Over heating but thanks to Haydn's cylinder head alarm, each time i have said it has overheated , I mean it triggered the alarm set at 100 and rarely went over 105 as the alarm did its job and I pulled over. Each time I lost a load of coolant via the expansion tank, so maybe I should have used the term over pressurised each time and not over heated.

In a few days I will update with what the garage's thoughts are. Thank you for your continued input

[surfkernow]

I made it to the garage they determined the head had cracked. So it is a full head placement, and some full compression tests. I am a little nervous as I don't know what caused the head to crack, albeit it could have been the water pump which was replaced as leaking or the blocked radiator.


I should have gone with my hunch 3 months ago when I suspected the head was cracked before the water pump, radiator and thermostat were changed and just had the head replaced but I was clutching at straws. I will update in a week or two if things are fixed.

Thank you for all the input

[haydn callow]

Make absolutely sure the garage has worked on Bongo heads before. If not get to one that has experience.......ignore this at your peril, you could be back here in 3 months.

[mikeonb4c]

I made it to the garage they determined the head had cracked. So it is a full head placement, and some full compression tests. I am a little nervous as I don't know what caused the head to crack, albeit it could have been the water pump which was replaced as leaking or the blocked radiator.


I should have gone with my hunch 3 months ago when I suspected the head was cracked before the water pump, radiator and thermostat were changed and just had the head replaced but I was clutching at straws. I will update in a week or two if things are fixed.

Thank you for all the input

Have to confess it nervewracked me but since it was done by an experienced Bongo mechanic nearly 5 years ago its been great. Bonus was its quieter probably as valve clearances all got reset. Its always good to fit new components where they might have contributed to head failure (blocked old rad, thermostat, water pump, temp sensor etc) so wouldnt feel to bad about it. Just hope it all settles with a new head. Good luck and keep us posted.

[surfkernow]

If I honest I don't think it makes much difference, with my luck something else will go wrong on the van in 3 months regardless at this rate. I understand your caution but

I have chatted to a lot of people over the last few months on this forum and on FB with similar problems who have been to Bongo specialists and their vans are still not working , I have spoken to people who have only recently purchased their newly imported Bongos from specialist Bongo garages that are having awful problems with their vans.

I agree Bongos have unique mechanical issues such as the cooling system, but the cost of getting mine recovered to a Bongo specialist again is too cost prohibitive, the garage local to me have fixed Bongos before...let's hope this is the end of all this

[Doone]

should have gone with my hunch 3 months ago when I suspected the head was cracked before the water pump, radiator and thermostat were changed and just had the head replaced but I was clutching at straws

Don't beat yourself up Ben, you made the right decision 3 months ago, as why replace a head when the system tested OK.

The water pump, radiator and thermostat were faulty (which is why it initially overheated) so needed to be replaced.

After they were replaced, it wouldn't have bled easily or driven as far as it did, without any problems, if the head had been cracked.

Sadly since then, it's leaked from other places. You've replaced 4 hoses, bled it a few times and it's overheated / over-pressurised a couple of times, which is what has finally caused the head to fail.

It's really bad luck that this happened after such a promising start and I hope everything's sorted for you soon.

[BongoBob]

I made it to the garage they determined the head had cracked. So it is a full head placement, and some full compression tests. I am a little nervous as I don't know what caused the head to crack, albeit it could have been the water pump which was replaced as leaking or the blocked radiator.


I should have gone with my hunch 3 months ago when I suspected the head was cracked before the water pump, radiator and thermostat were changed and just had the head replaced but I was clutching at straws. I will update in a week or two if things are fixed.

Thank you for all the input

I'm in pretty much exactly the same spot as you were ; Bongo going in to specialist later this week but suspect it could be the head. Can I ask how much yours cost to get fixed?

[JulesMartin]

When I bought my Bongo in October last year i bought it with known overheating problems. I took the head off and had it crack tested then skimmed along with the exhaust manifold full job came to £140. If you can wield a spanner it's not that difficult a job to do yourself. there are enough people on here with excellent knowledge and experience to help you through and doing a head replacement is a sure way to get to know your engine and all it's bits. if your head is cracked consider buying a second hand one and have it skimmed. absolute cleanliness is the key to head gasket replacement along with new head bolts being a must. by the time you've replaced the head and all the other cooling components you'll have a bullet proof engine that will make you smile and what an accomplishment.

[surfkernow]

Time for an update ...of woes....

New Cylinder head purchased, finally fitted at my local garage...i thought this would be the end of the saga....how wrong. The words "they had done away with the bleed pipe" made my heart sink.

I looked at the new cylinder head from Bongo Spares and indeed there was no connection for a bleed pipe. Some phone calls later , i was told I needed a three way adapter for the head so a bleed pipe can be connected. Aside from the fact I purchased a full brand new cylinder head kit which I was assured included everything i needed...I have a Bongo I don't dare drive. The garage assured me they bled it, albeit I am now sure how.

More pertient to this is when I did drive the Van the 1 mile down the road (before i knew about the bleed pipe) there was no power. As if the Van had no turbo anymore....i thought it would be impossible to cock up replacing a timing belt and cylinder head ...although my garage might have achieved this.

To end the day, on my trip to return the Van to the garage, my cylinder head temperature alarm which was reading 93 just died and began to read 001. That is being returned to be fixed....it is as if I had done something horrendously wrong in a previous life and i am being punished.

I need a three way adaptor, a bleed pipe and bung as the garage did not keep these. Then at least i have a van that can be bled. My garage needs to work out how by replacing a cylinder head and timing belt the Van has lost all power...it is almost like it is in limp mode

If anyone has any pointers on what they could have done wrong , please message me. I have an appointment with the CAB tomorrow with a view to going to the small claims court to address this calamity ...I can't be the only one that has spent thousands in parts and labour over 4 months and have a van i cannot drive.

[Doone]

Time for an update ...of woes....

New Cylinder head purchased, finally fitted at my local garage...i thought this would be the end of the saga....how wrong. The words "they had done away with the bleed pipe" made my heart sink.

I looked at the new cylinder head from Bongo Spares and indeed there was no connection for a bleed pipe. Some phone calls later , i was told I needed a three way adapter for the head so a bleed pipe can be connected. Aside from the fact I purchased a full brand new cylinder head kit which I was assured included everything i needed...I have a Bongo I don't dare drive. The garage assured me they bled it, albeit I am now sure how.

More pertient to this is when I did drive the Van the 1 mile down the road (before i knew about the bleed pipe) there was no power. As if the Van had no turbo anymore....i thought it would be impossible to cock up replacing a timing belt and cylinder head ...although my garage might have achieved this.

To end the day, on my trip to return the Van to the garage, my cylinder head temperature alarm which was reading 93 just died and began to read 001. That is being returned to be fixed....it is as if I had done something horrendously wrong in a previous life and i am being punished.

I need a three way adaptor, a bleed pipe and bung as the garage did not keep these. Then at least i have a van that can be bled. My garage needs to work out how by replacing a cylinder head and timing belt the Van has lost all power...it is almost like it is in limp mode

If anyone has any pointers on what they could have done wrong , please message me. I have an appointment with the CAB tomorrow with a view to going to the small claims court to address this calamity ...I can't be the only one that has spent thousands in parts and labour over 4 months and have a van i cannot drive.

Ian sells hoses in his Bongoland shop: https://bongoland.co.uk/product/hose-15-381a/


Did it start ok when you picked it up from your garage? Just in case it's a timing issue, new belt fitted and jumped etc.