V6 getting hotter
Discussion
Nice drive out on Sunday....(even the day old starter motor worked) but on the way back noticed the temperature gauge creeping up and up. It's ok in traffic (warm, but under control of the non-standard kenlowe fan) and ok at 40-50mph but as soon as I get to motorway speeds the fan kicks in and the temp goes up - showing over 100! It seems to be linked to engine speed, so slow down and it drops again, drop a gear or two and up it goes. There no drop in water level, no leaks, new water pump, no slack in the fan belt; could it be the thermostat itself? Any ideas? Or should I keep to a steday 50mph everywhere!
Are you sure the temperature is actually going up? Does the Kenlowe run off the Kenlowe standard issue capillary switch/blob (ie effectively isolated from the est of the wiring)? Do any of the other gauges vary with speed?
Just asking to remove the possibility that the engine is fine and it's a dodgy earth or failing alternator.
Regards
Iain
Just asking to remove the possibility that the engine is fine and it's a dodgy earth or failing alternator.
Regards
Iain
Thanks for your replies! Yes the fan does come on ok, and has does a fine job for the past 2 or 3 yrs, the fan belt is tight enough and the alternator seems fine too. Maybe the water pump isn't quite man enough for the job (should be, it's new) or a blockage somewhere sounds like the most likely explanation. Hopefully the weather will not be so excessively hot this weekend anyway so it might calm down a bit for now!
chassis 33 said:
Are you sure the temperature is actually going up? Does the Kenlowe run off the Kenlowe standard issue capillary switch/blob (ie effectively isolated from the est of the wiring)? Do any of the other gauges vary with speed?
Just asking to remove the possibility that the engine is fine and it's a dodgy earth or failing alternator.
I seem to remember that on my old car one of my guages changed when I put the lights on! (No not the voltmeter - well actually it did but you know what I mean!)] Now that I think back - it was probably the temp guage. I guess there was a problem with the electrics / earthing points.
The fuel guage seems to change rapidly too. Something to do with clear roads, sunshine and my right foot there though!
Good to see you and the Tazzie at the Woodman on Sunday James. Hope you got home OK.
>> Edited by nads on Tuesday 6th September 19:01
>> Edited by nads on Tuesday 6th September 19:02
There are several types of fault that could cause this. The most likely (and also easiest and cheapest to fix) is that the water and air passing through the radiator aren't in good thermal contact with each other. This can occur if there is an air lock in the radiator, or the radiator is badly silted up, or the innards have got covered in limescale.
It could also be caused by lack of air flow - perhaps from debris blocking the air path through the radiator.
I could also be caused by lack of water flow. This is pretty unlikely unless you have somehow managed to squash a hose, but could be caused by a slipping fan belt, absolutely knackered water pump or water aeration. At the bad end of the scale, this could be caused by head gasket failure, but it's not the most likely cause so no need to assume the worst. Just do a check for oil/water in the wrong places just in case.
It could also be caused by lack of air flow - perhaps from debris blocking the air path through the radiator.
I could also be caused by lack of water flow. This is pretty unlikely unless you have somehow managed to squash a hose, but could be caused by a slipping fan belt, absolutely knackered water pump or water aeration. At the bad end of the scale, this could be caused by head gasket failure, but it's not the most likely cause so no need to assume the worst. Just do a check for oil/water in the wrong places just in case.
mine does this too. in search of a fix I fitted an electric fan, changed the thermostat, changed the fuel pump and had the rad re-cored. The last 2 have addressed the engine getting far too hot and if the water level is good, it runs as cool as it ever has. However, it still tends to get hotter as speed increases and apparently when the engine is under load e.g. going up hills. The electric fan also seems to switch on a lot when cruising although it's fine in traffic. IM gonna investigate the distributor advance next as I'm running out of ideas. Any other idea's?
Geddy: did you mean to say fuel pump?
I got fed up with watching the water temp gauge go up and down so I just wired the main fans permanently on.
Seems to stay in the 90-100f range now, but the previous owner told me the gauge over-reads. One day I'll put an accurate electronic gauge on to test it.
I got fed up with watching the water temp gauge go up and down so I just wired the main fans permanently on.
Seems to stay in the 90-100f range now, but the previous owner told me the gauge over-reads. One day I'll put an accurate electronic gauge on to test it.
My theory... If you have a radiator in the engine bay and not the nose cone, then at higher speeds the airflow through the spoiler aperture will tend to go in a straight line, which sort of misses most of the radiator. You could try sealing the radiator sides/back to the nose cone, to force the airflow to change direction.
In standard form you would not see this happen as the viscous fan on the front of the engine will be active all the time at speed, pulling air through the radiator.
This seems likely, as at medium speeds you do not have any cooling problems.
Let me know if this helps.
In standard form you would not see this happen as the viscous fan on the front of the engine will be active all the time at speed, pulling air through the radiator.
This seems likely, as at medium speeds you do not have any cooling problems.
Let me know if this helps.
Don't forget the obvious...the Rad cap may be under par and not pressurising the system enough.
Just to fill up space, my V6 eases up from 180 to 200/205 - difficult to be precise - when I cruise at 85/95+ (on the Autobahn, of course !!) It went well over 200 when I took it round the 'Ring last year, but came back down quite quickly (unlike my heart rate).No electric fan.
My fan pressing broke at the centre boss last week because the waterpump turns out to be for a different 2.8 engine and the fan was about 2mm proud of the flange - it lasted over 3 years though! Made a terrible rattle,but welded up ok so far.Anyone got a spare? (2.8 late 81/ early 82)
My voltmeter acts like an ammeter too!
Just to fill up space, my V6 eases up from 180 to 200/205 - difficult to be precise - when I cruise at 85/95+ (on the Autobahn, of course !!) It went well over 200 when I took it round the 'Ring last year, but came back down quite quickly (unlike my heart rate).No electric fan.
My fan pressing broke at the centre boss last week because the waterpump turns out to be for a different 2.8 engine and the fan was about 2mm proud of the flange - it lasted over 3 years though! Made a terrible rattle,but welded up ok so far.Anyone got a spare? (2.8 late 81/ early 82)
My voltmeter acts like an ammeter too!
Thanks for the advice guys! Would be nice to have a rad in the nose cone, seems like a more sensible enough place for it but the old location has been ok for the last 22 yrs! Maybe a new rad cap, as long as it fits! (It leaves a permanent imprint in the bonnet lining).
Geddy - let's swap notes when one of us finds a solution. Maybe just waiting for some cold weather might help!
Geddy - let's swap notes when one of us finds a solution. Maybe just waiting for some cold weather might help!
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