running hot

[bryn1000]

HEW is running quite hot (2.25 petrol), the needle is just on the red...

ive flushed the rad and put in a 40/60 mix of antifreeze/summer coolant and water but its still very hot

I think the gauge is reading ok as the underbonnet temp is high and after a longish run there is a noticeable reduction in power.

Is there anything else i can look at? (ive got a new 9lb radiator cap coming)

[JMAP]

Is this a sudden change or gradual?
I'm thinking thermostat / sender / poor rad condition ...or head gasket.

[si_guru]

...or inefficient water pump!

Can you feel if water is getting to the rad? Is it exiting colder?

Becareful testing when the engine is running - that fan will have you fingers off!

[bryn1000]

its always run hot since ive had it...went for a good green lane run a few weeks ago and must have done a good 100 miles (1 tank full), i didnt go any higher than at the bottom of the red, but on occasions, steep hills etc it did loose a bit of power, i had a compression test done when i bought it and it was 160 on all cylinders so dont think its the head gasket...

[JMAP]

Ok, is anything dragging on the drive train - binding brakes for example?
Water pump: try grabbing the fan centre - engine off! - and see if there's any play.
Do you have a problem with the fuel guage as well? Could be an electrical problem - both share a common earth or the voltage regulator could be faulty.
I had a similar problem whereby the temp guage was fine until I slowed for a turn when I would notice it rise. It was an electrical problem caused by turning on the indicators for the turn that caused the guage to rise and then fall again as I turned them off. Does it progressively overheat at idle?

[BigJim]

HEW is running quite hot (2.25 petrol), the needle is just on the red...

ive flushed the rad and put in a 40/60 mix of antifreeze/summer coolant and water but its still very hot

I think the gauge is reading ok as the underbonnet temp is high and after a longish run there is a noticeable reduction in power.

Is there anything else i can look at? (ive got a new 9lb radiator cap coming)

What mileage are you getting? Is your mixture correct? I think too weak a mixture can make her run hot, experts will know for sure.

[bryn1000]

Ok, is anything dragging on the drive train - binding brakes for example?
Water pump: try grabbing the fan centre - engine off! - and see if there's any play.
Do you have a problem with the fuel guage as well? Could be an electrical problem - both share a common earth or the voltage regulator could be faulty.
I had a similar problem whereby the temp guage was fine until I slowed for a turn when I would notice it rise. It was an electrical problem caused by turning on the indicators for the turn that caused the guage to rise and then fall again as I turned them off. Does it progressively overheat at idle?

Just had its brakes done (brand new mot) so nothing binding...not sure about the waterpump (i was told it had a new one just before i bought it, 9 months ago, but will check)

yes i do have a fuel guage prob (reads full all the time) but as the engine bay gets very warm and the power drops off when running hard i think it might still be running hot (will check this too though!)

i sat and let it idle for 5 mins after fully warming up and it didnt go any higher...

thanks for your replys!!!!!

[bryn1000]

What mileage are you getting? Is your mixture correct? I think too weak a mixture can make her run hot, experts will know for sure.

Between 12 and 18mpg mixture was very week according to the very knowledgeable expert Kev Gascoigne who did my MOT, so he adjusted it...

Still warm though...i think i will check the waterpump and the electrics next as a good starting point

would the timing being too advanced/retarded make much difference?

[bilge rat]

are you certain its getting hot and not the guage telling porkys, drop a new sender in 1st. you said fuell guage red high ?. dont know much about series landys but most cars used to run 9 volt guages so had resister on back of dash, they were nearly always paired fuell and water temp, might be worth a thought.hope this helps alan.....

[bryn1000]

its a 24v FFR so its got 2 senders, so i think its an earth rather than the senders or the gauge...

the temp does seem to rise very quickly, its running half way up the gauge after a mile or so...

if i can find a 24v gauge on eBay i will give that a go too...just to make sure

[bilge rat]

havent got a clue how there wired never had anything to do with 24 volt, you say mile up the road its half way seems a bit extreem, id of thought even with a sticky stat it would have took longer than that. just a thought let it cool completely, start check hoses keep your hand on the top hose when the stat opens you'll notice a considerable difference in hose temperature (so you know the vehicle is roughly at running temp) at this the guage should be half way, a vague way of checking but it may help, idealy you could do with a capilary type guage to test it or just to eliminate the guages sender e.t.c . alan....

[BigJim]

Have you checked the thermostat? May be sticking shut. easy to test take it out and put it in boiling water, should open, add cold water slowly, should close, pour out some water, add more boiling, watch it open, repeat until you know it doesn't work or are happy with it.
Essential to make tea or coffee with the first boil, to be drunk as you watch it open and close.

Even if it is stuck completely shut, you still have a quick warm up, I still suspect you may be running weak. What are your plugs like?

One thing to do when it has warmed up is to open the rad cap (V E R Y V E R Y S L O W L Y and carefully with lots of rag, may squirt steam out) and put in a thermometer, then you will know what temp it really is.

[Wurzel]

When I bought my '83 SWB, the temp gauge was running regularly on the low side of the red. Turned out to be the voltage regulator that's mounted on the back of the dash. The telltale sign was that the fuel gauge would rise and fall in sympathy with the temp gauge. The regulator was very cheap to replace, so might be worth trying (Assuming that the single regulator supplies both temp and fuel gauges on the 24v model).

[bryn1000]

just checked the prices for a thermostat (just incase) and they are soo cheap im going to buy a new one to illiminate that, however there are two both advertised for 2.25 petrols

74deg or 82deg

any ideas?

[rusty_wingnut]

well use 74 in summer and 84 in winter, i had this problem on my MGB after fitting the stage 1 head, it was running to hot due to:
1, sticking thermo
2, timing being a bit out

after rectifying both and swapping rads it was sorted

[nemchenk]

deja-vu :)

(Mine is running just like yours, bryn, and I did the same re the thermostat as you are planning -- took the old one out and bought a new one. Flushed the system repeatedly, and using a solution, but I think she is still running hot as, with no thermostat fitted she runs around the "N" letter of the guage. Maybe try that? Take the old 'stat out (I used this as an opportunity to reverse-flush the engine block and heater) and see how she runs with no 'stat in.

Don't think it's my guages, as they seem to be ok -- the next culprit I reckon is the water pump (the cover look awful, all rusted and manky :p ) and the rad (still plenty of rustiness on the cores even after flushing.) But, since I'm doing an engine swap (sometime in the next 6 months, I hope :rolleyes: ) I will wait until then to find out :D

Anyway, good luck, and let us know how you get on with fixing the problem :)

[Grandaddy_low]

its a 24v FFR so its got 2 senders, so i think its an earth rather than the senders or the gauge...

Is the second sender not for the oil temp?


if i can find a 24v gauge on eBay i will give that a go too...just to make sure

I been looking for one of these for months (mine corroded completely inside). They seem quite rare/expensive.

G.

[Snagger]

If the vehicle has been kept in a hard-water area, it's likely that limescale has built up inside the rad core. This partly blocks the rad, but also acts as an insulating layer. A strong solution of kettle de-scaler may work (remove rad to do this), but there's a good chance you need a re-core.

[JMAP]

Some time ago I had trouble with an overheating Mini on a recon engine which I could not cure despite flushing rad change etc.
I used one to flushing preparations - the Holts 2 stage one. I think it's quite an agressive chemical and come in two parts: one to neatralize the other.
Despite many flushes producing clear water, after using the flush prep the amount of rusty goop that came out of the engine was staggering. I can only assume that the block had not been properly prep'ed at recon. Anyway after that it run considerably cooler. Will happily idle for ages in hot weather without a slightest suggestion of overheating. I've just bought one of these for Landy but haven't used it yet - it's about £5.

[bryn1000]

Is the second sender not for the oil temp?



I been looking for one of these for months (mine corroded completely inside). They seem quite rare/expensive.

G.

It has two fuel tanks , hence the two senders needed...

never seen one so far on eBay, so must be rare...looks like we will be fight ing over one when it comes up :D

yesterday i changed the radiator cap and noticed that the spring was very weak compared to the new one...also added some exhaust wrap to the down pipes to try and reduce under bonnet temp...

idled HEW at about 1k to 1.5k rpm for 10 mins and the temp didnt rise above half way...even reving hard for a few seconds didnt change it...will go for a drive if i get some time and see what its like under load...