Bongo Fury

Agreed......although they do tend to run "slightly" warmer the hotter the outside temp gets. But you are quite right about the bottom hose only getting warmish.
I do, however, know a man/woman who would disagree with that FACT.

haydn callow wrote:Agreed......although they do tend to run "slightly" warmer the hottet the outside temp gets. But you are quite right about the bottom hose only getting warmish.
I do, however, know a man/woman who would disagree with that FACT.

I wonder who that is/was/will be?!?!

Hi once again

Hadyn Wrote

Your engine should run at the same temperature in summer or winter - that's what the thermostat is for.
The hottest my bottom hose has ever been was lukewarm - there is a feeling that most of the cooling is actually done by the heater radiators.

I agree and understand that, but my fans are running almost all of the time to cope with trying to cool the engine now. Will they cope in summer when the air passing through them is hotter. Hence I'm concerned something isn't right. Bleeding the system also makes no difference so little chance of an air lock.

Do all Bongo rad cooling fans run at this time of the year. Any replies would be appreciated.

Steve Mc

Not my quote...
Which fans are running?
Is it the BIG one that cools the engine compartment?

mister munkey wrote:The Mason Alarm has bought issue this up before. Because it gives a more positive reading over a narrower temperature band, they sometimes need a little tweaking to suit each individual engine setup.

Most seem to end up setting theirs at 4.5.


Have a quick search, you'll find plenty on here.

Sorry to sound dim, but I might have missed the point of adjusting the alarm.

Deos the adjuster adjust the beeping that the alarm makes and the position of the gauge pointer or only the beeping.

It adjusts the point/temp at which the alarm goes off, has no effect on the guage reading. Each Mason will have slightly different values/parameters as I think Dave Mason mentions either on the discussion on here several months ago when he first modified them for the Bongo or possibly on his site.

Thanks for the reply

Sorry Haydn,
Wrong quote. Sunday morning all a bit blurry still.

It 's the main radiator fans. A/C is off. I am wondering if the fan temp / cut in switch maybe faulty or there is an air lock in that area. The other day when I switched the engine off and the fans were running I switched on the ignition again and the fans had cut out. Maybe just coincidence. Can anyone remind me where the Otter type switch is located.

Anyway, I think some of us are having a clearer idea about the Mason alarm. I'm thinking that it might be best to largely ignore the temp gauge and listen for the alarm. If it's set between 4.5 & 5 and it rarely sounds then things are ok?

Have a pleasant Sunday one and all.

Steve Mc

Why not fit one of these digital temp guage. I fitted one with the sensor siliconed in to one of the spare bolt holes at the top front of the head onthe exhaust/passenger side of the engine. Reads from upper 90's up to about 115 degrees C depending on loading. At least you can monitor what's actually going on with the engine temperature

My return hose runs hot when the engine is up to temperature, not as hot as the top of the radiator by any means as it has run through the radiator and has been cooled somewhat.
Have you thoroughly flushed and cleaned your cooling system?
Its best done with the thermostat removed so you can flush all the way through without any restrictions. Test the thermostat by immersing it in a pan of water and heating it up, when the temp reaches around 82 degrees C then the thermo should start to open and fully open the hotter it gets, if not then replace it.
This may cure your problem, hope it helps.

Thats how it should work in a cooling system, have you checked that you have a stat fitted?

I have had a few Bongos visit me to have a coolant alarm fitted. I make a point of "feeling" the bottom hose after they arrive. These are all Bongos which have travelled a lot of miles to get to Somerton. All have been running well for many months. All of them had what I would describe as a warmish bottom hose. I would suggest that if you run normally with a Hot bottom hose ,you have the impending problem. It would be interesting to know what temp your clyinder head is running at. Mine runs at around 90 C and never goes over 100 C. However we don't really go above 70mph but we do tow a small caravan.
Did we not do a poll on this subject some time ago??

The Great Pretender wrote:

haydn callow wrote:Starts to open at 82 C ?
Fully open at 82 C ?

Yes but if the bottom hose is only warm after 200 mls it isnt open is it?

If you are driving at highway speeds in under 20 degree C conditions, and light load, you will find that the thermostat stays closed and the bottom pipe won't warm up until a couple of minutes idling. The engine seems to get enough cooling when you are doing 100km/h.

I noticed I could drive 10km from cold, in traffic, and it still had a cold bottom pipe, and really had to be idling for 10-15 minutes before it would start circulating properly. I changed the thermostat, I think it opens earlier now.

'Stat begins to open at 82 and fully by 95.

The Mason alarm makes the gauge read real temp and 1 o'clock seems the norm, although I've seen one between 12 and 1.

The alarm should be initially set low and increased until the time the fans come on which is 108 deg. that way the alarm will not come on until something causes the system to overheat. 4.5 - 5 seems the norm.

I think you've a partial cooling system blockage smac, probably radiator - I've mentioned this earlier.
It's not bad enough at the moment to be causing you problems but the fans are doing their best to overcome a radiator blockage causing the coolant to run too hot.

haydn callow wrote:I have had a few Bongos visit me to have a coolant alarm fitted. I make a point of "feeling" the bottom hose after they arrive. These are all Bongos which have travelled a lot of miles to get to Somerton. All have been running well for many months. All of them had what I would describe as a warmish bottom hose. I would suggest that if you run normally with a Hot bottom hose ,you have the impending problem. It would be interesting to know what temp your clyinder head is running at. Mine runs at around 90 C and never goes over 100 C. However we don't really go above 70mph but we do tow a small caravan.
Did we not do a poll on this subject some time ago??

So if the bottom hose runs 'hot' why would that be a problem as it needs at least 82c to open the stat?