High Mason Gauge reading

[ADAMD]

Hi
Having fitted a Mason alarm, and set off for a surf trip to Devon,
I had the needle very high a lot of the time (motorways + hill climbs)
and at times over the top mark.
I have a temp probe on the head under the passenger seat, and this never rose much above 100 deg C.
I have no reason to think my engine is running any hotter than it always has.
And the trip was fine - I just set the alarm to 6, and ignored the guage, using only my head temp readout.
Has anyone else seen this sort of result, or is my Mason alarm faulty?
Thanks
Adam

[mikexgough]

Mine has never gone that high, mine goes at most 1/3 of the distance between the upright and the H

[apole]

Hi,

Mine doesn't got that high either. Could it be the temp probe is not giving the same reading as the coolant temp sensor perhaps?

Out of interest, where did you get the probe temp gauge and how does it connect.

Regards

Andy

[miker]

Mine was going that high until I changed the thermostat and now it reads about 1cm away from the H (about 1 oclock). My advice, change your thermostat and if that doesn't work suspect a blocked radiator core?

[haydn callow]

I agree with the above......where exactly do you have the temp sensor located ? My temp gauge never goes above 95 unless towing, then 105

[ADAMD]

The temp Probe is in the tapped hole on the passenger side of the head
above the exhaust manifold, Your original position I believe Haydn.
This guage rarely ever goes above 100, but at 94 you can see where
the bongo guage is from the pic.

[haydn callow]

In that case ..your readings are very good.
Suggest you move your sensor to the "new" recommended position whenever you have half a hour to kill....(back of the cylinder head...tapped hole)
Don't know why your Mason is reading high....(faulty sensor ??)

[missfixit70]

A few seem to be doing this http://www.igmaynard.co.uk/bongo/forum/ ... &start=120 , I'd suspect the sensor initially, but it may be worth contacting Dave Mason & seeing what his take is on it

[tonic]

I'm glad it's not just ours that reads so high with a mason alarm ie same as ADAMD. We don't have any other temp reading device so don't know the actual temp. Because of the needle been so high & making us totally paranoid it's off to the garage tomorrow for a check up.

[haydn callow]

tonic....don't let them near your cooling system unless they know all about Bongos.

[tonic]

tonic....don't let them near your cooling system unless they know all about Bongos.

Thanks Haydn for the concern. Luckly we are near to Hillside in Derby & always take them there for services & issues

[phil 1]

Hi
Mine also goes that high when sat in heavy traffic for a long time.
The first time it went that high was august bank holiday stuck in the 3rd lane in the worst traffic jam I’ve seen. I had to sit and watch the needle rise higher and higher just as the needle started to enter the H area the alarm went off and as I started to cry at the thought of my engine cooking its self to death I heard for the first time the fans kick in and the needle dropped rapidly back to its normal position . We were sat in that traffic jam for several hours and watched this happen several times as soon as we got moving every thing returned to normal.
Do you think I may have a poorly cooling system ? .

[haydn callow]

NO

[wanderingscotsman]

Mine sits around the same, but not always quite as high. I went through the whole panic thing when I fitted it, but it does lower a bit when the fan kicks in….but not nearly as low as others. I had it in to get new glowplugs and they checked the temp with their laser reading thingymajig and reckoned all was ok…. So I’ve stopped worrying so much now. It went up and over many mountain passes in Italy recently and was ok. It’s going in this weekend for a stuck blind, so maybe I should get the stat changed then…. Does this mean it needs coolant etc changed as well? Reluctant to tamper with it if it doesn’t need it…… just started getting over the bongo paranoia after the first few months

(not helped when I discovered a wet passenger carpet last night….. leaky water bottle – phew!)

[nfn]

My Mason-adjusted gauge also sits at about 1 o'clock in normal driving. I got it up close to the line (like in the photo) once this summer with six people in the van, driving at 65-70 up a long (but not especially steep) hill. Two of the passengers were quite large and plump. The radiator and thermostat in my bongo have possibly never been replaced (1995 model). I figure that the Mason gauge is useful for showing trends over time -- as the cooling system gradually clogs up/thermostat gets slow to respond, etc., it should show up on the gauge as slightly higher readings than before.

Phil 1 -- if the needle rises in traffic jams the cooling system is probably not working efficiently (unless it's very hot outside). The Mason gauge on my bongo tends to fall a bit if idling in traffic jams for a long time (although the scavenger fan has come on once or twice because hot air was not being cleared from the engine compartment while the van was stationary).