Thermostat /temp Question

[Maccer 0]

Hi All,

 

I'm trying to work out if my thermostat is shot. I don't have a thermometer to whip it out and test with hot water so thought I could just judge by the heat on the pipes. The top pipe to the rad gets warm before the water temp gauge gets to the first mark, anyone know roughly what temps the marks on the dash gauge relate to?

 

Cheers, Mike

[welshpug 1,657]

Here's a picture with the temperatures for the oil and coolant temperature gauge highlighted;

 

 

if you're unsure of it I would just replace the thermostat, it's not expensive at all.

[pug_ham 244 3 Cars]

Why do you think its shot?

 

g

[Maccer 0]

Ah, thanks for the pic. Mine must be opening up about 60-65c then!

I was thinking the heater wasn't particularly strong anyway on startup but with winter here I've also had to set the idle a bit high because otherwise there is a few minutes after the SAD closed off when it runs like s*ite and wants to stall (basically until the water hits the first bold line on my guage about the ~80c mark in that pic.) I'm guessing if the stat is sending water out to the rad too early then the block might not be retaining enough heat to keep it running right without the extra air.

I'lll swap it out anyway and see how it goes. Cheers

[pug_ham 244 3 Cars]

What spec thermostat have you got in your car?

 

I have a 75'c one in mine which will start to open at 60-65'c & be fully open at 75' but I'd expect that with the standard 82' or 89' then it would be into the 70's before it starts to open.

 

No heater will be strong on start up, it'll take a few minutes at least for the coolant to start to show any increase in temp & longer to settle after the thermostat opens.

 

g

[Maccer 0]

Not sure what spec the current one is, I'll have a look once I've changed it out. My car's just a standard 1.6 though so I can't imagine why it would have anything lower than the standard fitted?

I'm pretty convinced it must be opening too soon as the rad pipe starts to warm up after about a minute just on tick over from cold. Guess I'll know for sure if there's any change when I fit a new one!

[Maccer 0]

Swapped them over today. The old one was an 82c, so is the new one. Seems to have done the job, now the car warms straight up to the 80c mark and goes up to about 90c after a drive. Before hand it would only reach the 80c mark after a 30 mile drive!

Idle after coming off the cold start valve is also greatly improved so I've been able to set the idle back to 1100rpm once its at normal temp and it runs great.

[welshpug 1,657]

should be able to take it down to 875-900 if the afm is good

[Maccer 0]

I think that might be a bit of an ask of mine! I settled with 1100 because when I put the headlights, blower and rear-demister on the extra load takes it down to about 900-950, and when you blip the throttle in that situation she struggles into stall territory for a second before picking back up.

Although.. I'd only really be using all of those together at startup when its still on the SAD... suppose I could tweak it down a little. Hmm, maybe I'll have a little play!

[welshpug 1,657]

got a haynes workshop manual? that covers setting it up from scratch