Temperature.

Hi all,

We own a Commer Walk Thru, 1972, 6 cilinder.
We have replaced all the water hoses, placed a brand new radiator, thermostat and temperaturemeter. Engine has been flushed etc.etc.

It's now about 0 degrees celcius here but the temperature meter still says the engine is runnning hot - we can still put our hands on the radiator without burning them.

Does anyone have any suggestions?


Check www.commerwel.nl
 
hi ya just looked at your link fantastic van:D have you checked to see if the water pump is actually moving the water ?? as if its not the engine will get hot a lot quicker than the rad will get warm ? does the gauge go strait to hot( instantly) or is it gradual ..
 
Hi dozer, Thanks for your reply and compliment.

We are quite sure the waterpump is working. When we installed all the new hoses etc. we started the engine. At a certain moment the thermostat opens and the radiator (witch we filled with collingfluid) was empty in no time ... sucked in the engine.
So, filled it up again etc.

Is there a way I can double check if the pump works????

I can't realy say that the engine becomes hot a lot sooner orso as the radiator, it al seems very normal... like a normal car.

When I start the engine it takes quite a while before the temperaturemeter starts to climb. But, when it does starts it doesn't "stop" at normal but just keeps on climbing to max.
If it is at max and I increase the RPM by pushing on the gaspedal for a while, the temperature starts to drop to "normal".

I THINK that it's just the temperaturemeter. It seems to me that when it shows "max" it should extually be on "normal"... but how can I check this ???

Thanks a bunch guys !
 
when you no that the thermostat is open ( top & bottom hose same temp) take the cap of the rad ( gently ) kin hot . and rev the engine hard & fast if the pump is doing what it should the water should ,if there's enough in there , piss out like a fountain or at least flow past the hole in the rad at a fast pace . speed of gauge rise means your wiring is OK coz if it had gone straight to hot you would of had a short .. but are the sender & gauge a matched set ? because i v had a gauges that need a lower power feed to make them right (regulator) .. if you can borrow another gauge and try it at least you will have peace of mind about that. what sort of fan has the engine got ?? but if you rev it and it gets cooler id guess flow rate.. ???
 
worth checking that it is actually full of water,including the heater as an airlock will cause similar symptoms :)

"you were only supposed to blow the bloody doors off"
 
Have you had the head off recently? Paulfordy had a similar problem on his PB. He found he had fitted the head gasket the wrong way round and had managed to block of one of the water ways, it it possible on a Walk Thru?
 
Hi all,

Thank you so much for your replies.
This weekens I will check if the pump works like DOZER explains.
The new temperaturesensor I placed should me original Commer, so it should not be a mismatch with the gauge.

Does anyone know what the temperature should be if the thermostat is open and the top and bottom hose have the same temperature?
Maybe I can check the temperature then with a digital temperature meter... ?

@ commeracer - How do I check this / know this for sure?


Check www.commerwel.nl
 
Could a faulty voltage stabiliser be the cause of a wrong reading on the temp guage?
 
quote:
Originally posted by Panky

Could a faulty voltage stabiliser be the cause of a wrong reading on the temp guage?



Good thinking, I was already planning on renewing (upgrading with some electronics) the stabiliser this weekend to ;)
thanks !

Check www.commerwel.nl
 
you do need to work out if it is actually running hot or if it is just a guage problem. i use a hose pipe to force water through the system. :)

"you were only supposed to blow the bloody doors off"
 
you could try taking the thermostat out and running it - this should just let the water run round the system, so engine will take longer to heat up, but would normally stop the engine overheating.

One other thing, don't know if someone's mentioned this, but have you checked the wiring, you could be getting a short which would affect the reading.

I've got a diesel in mine and it runs around 85 degrees I think... if everything's working, I guess the needle should be in the middle of your temp gauge, or maybe just a little over for an older vehicle.

also if pump is working you could pull the end of the exit hose off and run it briefly - water should come out of the end of the hose if it's all ok (same sort of thing as the radiator) - if you've taken the thermostat out then this should happen even when it's cold (so avoiding getting scalded!)
 
Just had a look thro your photos - van's looking great, lots of nice hi spec stuff going in as well!

By the way, one of the things I did a few years back was replace the old oil filled air filter with a modern(ish) air filter, taken off an old Iveco I think. Fitted straight on to the old system and a lot quieter than the old one which used to rattle and suck air very noisily. Probably better at filtering as well and means I can change the filters every year.
 
Hi guys,

Just an update.
This weekend we tested the water pump, it works perfectly.
Then I begun to check the elektrical part and found the problem.

The temperaturegauge (-) is connected to the ground (no problem there ;) )
The + is NOT connecter to a stabilasor but straight connected to the temperature meter.

It now seems logical that the gauge is not giving an accurate reading.

So, does anyone know if below scheme is correct... ?
scheme.jpg


Thanks !

Check www.commerwel.nl
 
Looking at the PB wiring diagram the circuit looks more like this

image001-1.gif


Apologies for the crude diagram.
 
Hi Panky,

Thanks for your reply.
Regarding to your wiring diagram I have some questions.
When I use a voltmeter between the ground and the temperature transmitter, I read about 8 volts, meaning the temperature transmitter generates a small current (+)
Looking at your diagram this would mean the gauge is connected to a + via the voltage stabiliser and to another + via the temperature transmitter.

Or.. I might be entirely wrong... which wouldn't suprise me either ;)

Thanks in advance for your replies !!!

Check www.commerwel.nl
 
Is that 8v with everything connected up from battery to temp transmitter? As far as I know the trans shouldn't generated any power as it is a resistance device that changes with temperature so giving a varying indication on the gauge. If the reading is between transmitter and earth (with everything connected up and ignition on) then you are measuring the resistance of the transmitter at that particular temp. As I said before apologies for the crap diagram, what it is supposed to show is everything in series from supply from fuse box right through to the transmitter, I've altered it to hopefully show what I mean.
 
maybe try another temperature sensor? these are pretty cheap and can easily go wrong, so might be letting current run thro it when it shouldn't, so giving a reading.

Am i right in thinking you've got a manual? if not i can send you a spare one (dated '74) which might help.
 
quote:
Originally posted by Panky

Is that 8v with everything connected up from battery to temp transmitter? As far as I know the trans shouldn't generated any power as it is a resistance device that changes with temperature so giving a varying indication on the gauge. If the reading is between transmitter and earth (with everything connected up and ignition on) then you are measuring the resistance of the transmitter at that particular temp. As I said before apologies for the crap diagram, what it is supposed to show is everything in series from supply from fuse box right through to the transmitter, I've altered it to hopefully show what I mean.





Hi,

Thanks for this explanation, it's now perfectly clear to me !
I also understand now what how everything whould work.
Only thing that is not clear to me is why I read 8 volts between the temperature transmitter and the ground (disconnecter everything).

@ commer walk thru,
I have replaced the old temperature transmitter with a new one - both act the same, so I think this is normal.

Maybe it's possible for one of you guys to put a voltage meter between your temperature transmitter and ground and see if you also measure something ? Again, I disconnected the connecter from the temperature transmitter before doing this.

So... finally, the wiring diagram should look like this
scheme2.jpg

is this correct?

Thanks again !

Check www.commerwel.nl
 
Hi cbx if your getting 8 volts at the transmitter with the transmitter wiring disconnected then i'd check the engine earth it sounds like you might have a bad engine earth connection
 
Back
Top