ongoing overheating issues

[jimbob-mcgrew]

ive been having heat issues for quite a while.

so far ive :

- checked the fueling.
- checked the timing.
- renewed the coolant liquid.
- fitted a new thermostat.
- tried different spark plugs.
- cleaned the temp. switch.
- cleaned the rad fan switch.
- checked all the jubilee's on all coolant pipes.
- partially flushed the rad

... still having issues tho !

water's getting around the system, so I don't think the pump's the problem.
I was thinking possibly the head gasket waterways might be clogged up ? what you guys reckon ?
anything ive missed out ?

[jimbob-mcgrew]

I guess I should really check the pump to be certain

[John]

What symptoms do you have, just overheating?

[conza123]

i had a bit of a overheating problem with my 1300sr turned out to be expansion bottle cap,

do they do coolant flush just to flush the hole coolant system

[jimbob-mcgrew]

What symptoms do you have, just overheating?

its not in the red, but higher than it should be, and ive had it conk out twice in extended traffic because it got too hot

[conza123]

ive had it on some vws and bmw water pumps,

where the embeller is plastic it warms up and expands off the shaft so doesnt pump when hot and when it cools down the embeller shrinks back on to the shaft and looks ok when you remove it.

but if you gonna take it off then you mite aswell replace

[jimbob-mcgrew]

i had a bit of a overheating problem with my 1300sr turned out to be expansion bottle cap

was yours leaking ?
mine seems pretty solid, possibly too solid lol

[conza123]

was yours leaking ?
mine seems pretty solid, possibly too solid lol

mine whernt holding the pressure so it was over heating a bit so borought a new genuine cap and havent had a problem since

[jimbob-mcgrew]

ive had it on some vws and bmw water pumps,

where the embeller is plastic it warms up and expands off the shaft so doesnt pump when hot and when it cools down the embeller shrinks back on to the shaft and looks ok when you remove it.

but if you gonna take it off then you mite aswell replace

I need to check that next ideally, I don't fancy pulling the head off if I can help it.
I would have don't it earlier, but got posted a round tooth pump and belt. didn't realise I needed a square tooth till I pulled the cover off

[conza123]

I need to check that next ideally, I don't fancy pulling the head off if I can help it.
I would have don't it earlier, but got posted a round tooth pump and belt. didn't realise I needed a square tooth till I pulled the cover off

if you get a new pump make sure it has a metal impeller so you dont have plastic impeller problems

[jimbob-mcgrew]

if you get a new pump make sure it has a metal impeller so you dont have plastic impeller problems

will do :thumb:

[meritlover]

you have not mentioned if the rad fan comes on properly.

there are still some possibilities:
the higher temp is due to the higher seasonal ambient temperatures and is nothing really to worry about,
the rad fan is not cutting in and struggling to drop the temp
the aluminium fins are bent preventing air flow through the radiator,
the core is scaled/fouled and heat transfer is inefficient.
block is scaled as above
you dont actually have an issue and the stalling is due to hot air temperatures.
head gasket failure is possible but unlikely. its not a big job anyway.

the OE gauge is not linear and not at all accurate which makes the problem often look worse than it is. Without knowing just how bad the issue is makes it tricky to diagnose. just turn the heater up and open the windows.

[jimbob-mcgrew]

the rad fan cuts in ok lover boy, (a bit late mind, at 3 quarters on the gauge) and doesn't do a great deal to the gauge.. once it gets hot, it doesn't seem to want to come down, and gets to the point that the fan is cutting in a out continually.

even in the cooler evenings, driving fast-ish at low rpm, with the rad getting flooded with air and hot air pouring out the vents, the temp is still above half way.

yeah, I agree the gauges can be misleading sometimes, I trust the stat and the rad switch more myself. it probably wouldn't bother me, but once the cars up hot, and stays hot, it will eventually after some time, suddenly run horrible, and then it shuts down, and I have to push it to the side of the road like a chump lol.

I have a smaller rad from a 1.2 that I thinks ok internally. should I try it to rule out the scaled up core ?

im in the process of ordering a new pump and temp sender to rule out others

[jimbob-mcgrew]

is this guy lieing about this sender fitting ALL mdoels ?

http://www.ebay.co.uk/itm/Vauxhall-Combo-Frontera-Temperature-Gauge-Sender-Unit-/190430487060?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item2c568aa214#ht_1379wt_1020

or should I buy it

waterpumps on its way now ... I need to go to my least favourite shop to get a cambelt next

[meritlover]

The fan wont be able to get it as low as it would with the car driving forward. There simply isnt enough airflow. The important thing is that its preventing it from rising further. The switch will cut in and out as it hovers between the deadband. Make sure you are using the return line on the carb and that its not plugged. This prevents vapour lock and stalling in hot conditions.
the gauge sender is the same across all models, the chances are its the gauge its self that's the issue.

you dont need to change the cam belt, you can re-use it (unless its due a change anyway).

changing the rad isnt a big job and will eliminate it from the equation....its up to you, if you're doing the water pump you will loose most of the water anyway, so thats the time to fit it.

xx

[TeddyThom]

An easy fix to the problem of it over heating in traffic, is to set the rad fan on a separate switch, so you can turn it on and off at will. Iirc, the motorsport boys do that.

[jimbob-mcgrew]

The fan wont be able to get it as low as it would with the car driving forward. There simply isnt enough airflow. The important thing is that its preventing it from rising further. The switch will cut in and out as it hovers between the deadband. Make sure you are using the return line on the carb and that its not plugged. This prevents vapour lock and stalling in hot conditions.
the gauge sender is the same across all models, the chances are its the gauge its self that's the issue.

you dont need to change the cam belt, you can re-use it (unless its due a change anyway).

changing the rad isnt a big job and will eliminate it from the equation....its up to you, if you're doing the water pump you will loose most of the water anyway, so thats the time to fit it.

xx

luckily my 2e is one of the return line versions.
cheers, I think ill get one of those switches in that case, as there only a couple quid.
I thought id best change the belt with the pump, as ive got no paperwork for when it was last done, coulda been a while back.
ill give the rad a go too, see if it makes any difference.


An easy fix to the problem of it over heating in traffic, is to set the rad fan on a separate switch, so you can turn it on and off at will. Iirc, the motorsport boys do that.

yeah, that crossed my mind once or twice TT. ive done it before in the past to over-come dodgy wiring on the rad switch circuit.
I think after I do all the bits, if I still have concerns, ill bypass the switch for a manual over-ride.

##

this cars turning into a nightmare at the moment, ontop of all the regular service stuff and the heat issues, I have to change the front brakes, the rear brakes, a nearside c.v boot, gotta get the sill patched, and a few other small bits.... ive come too far to stop now tho, she WILL get another mot ticket and stay as the daily ! :)

[jimbob-mcgrew]

ok - so I changed the waterpump and timing belt, flushed the rad out too.

the old waterpump turned out to be a metal fin type (GM unit) and had practically no wear, as far as I could tell.
I had a bit of an airlock issue after re-fitting, but a good thrashing down a lane sorted that.
temperatures are a smidge better now, but its still not happy, it still gets hot on long runs in traffic, and eventually goes into a sudden spaz-out mis-fire mode and cuts out on me.

im thinking bollox to it now, im going to change the entire ignition system next - coil, plug leads and dizzy. see if that helps.
if that doesn't work, then I suspect it might be carb related ?
will report back again when I find the culprit :wall:

[meritlover]

it could be something electrical like the ignitor or trigger breaking down under heat. it also could be fuel related. its hard to tell without being able to simulate it and watch what's happening.

[jimbob-mcgrew]

when you say ignitor and trigger, are you talking about the internals of the dizzy ?

[meritlover]

yes. there is a reluctor, field coil and ignitor inside the distributor which fires the coil.

both the field coil and ignitor can break down under temperature just like any other electrical component.

[jimbob-mcgrew]

hmmmm.....

ok, cheers bud, ill investigate.
I need to open it up to pull the vac advance out, so ill have a closer look

[jimbob-mcgrew]

last time I had it off, there was a slight oil leak from the cam housing O-seal actually.. could hot oil do damage to the parts ?

is that seal replaceable ?

[marc69]

You have probably done this but, the ignition adavnce will need to be right too, so the car isn't retarded at higher revs, I had a similar problem in an ohv Nova, the plugs used to overheat after 60 miles and then stall.

Eventually I changed the dizzy as everything else had been changedalthough it seemed fine with no slackness, 6 years later it has never done it again so was clearly something in the dizzy.

[jimbob-mcgrew]

You have probably done this but, the ignition adavnce will need to be right too, so the car isn't retarded at higher revs, I had a similar problem in an ohv Nova, the plugs used to overheat after 60 miles and then stall.

Eventually I changed the dizzy as everything else had been changedalthough it seemed fine with no slackness, 6 years later it has never done it again so was clearly something in the dizzy.

cheers marc, that's good to know.
even on oldskool basic carb cars, theres still a couple of electrical bits to confuse me lol

[jimbob-mcgrew]

looks like you might be right ML.

the wrapping on the induction sensor has crumbled away. possibly expanding with heat and shorting out or something ?

http://i289.photobucket.com/albums/ll227/photon_09/additional/diz1.jpg

[jimbob-mcgrew]

so rebuilt 1 good one dizzy from 2 buggered ones.

hopefully its cool, ill find out.

I have one other suspect if its not fixed - the vacuum hose going to the unit is clear plastic hose and not a sturdy plastic pipe like it should be. im thinking possibly it could be getting squidgy at high temps and collapsing in on itself when suction from the carb gets applied, inhibiting the dizzy from auto advancing. ( just a thought ) ill keep an eye on it.

the carefully put back together and cleaned up dizzy :

http://i289.photobucket.com/albums/ll227/photon_09/additional/diz2.jpg