Diesel thermostat definative answer - Page 89

LeRich · 19th January 2011, 19:32

I've just ordered a QTH107 'stat from Rapid Car Parts for £8 delivered. Hopefully it'll be fitted this weekend assuming it arrives inthe next couple of days. I'm looking forward to seeing what difference it will make to the engine's efficiency and entering the 'club' :lol:

PaulR · 21st January 2011, 12:31

I read this thread more or less from end to end last night (phew I need new glasses!). I always assumed that the pathetic heater on my car was caused by the lack of a FBH but I tried the temperature this morning and it never got any higher that 65 degrees on my 15 mile journey to work.

I have just telephoned Specialist Components and they are sending me an in line thermostat. I hope the cold weather lasts long enough to enjoy the warm cab I am now expecting!!

As a slight aside, I also run a 1962 Rover P4 100 with a totally analogue capillary water temperature gauge. You can clearly see the movement of the needle on that as the thermostat opens and closes. It never goes out in salty winter weather but it is very interesting on a hot day. The movement of the fuel gauge when you drive round a corner is also something to behold.

Paul

Jules · 21st January 2011, 13:00

Yes Paul give me my analogue gauges of my old triumph Stag any day!

Good job Aircraft gauges aren't calibrated like the 75 and most other modern Car Temp gauges

Mind at least 75's have a gauge.
A lot a small cars now only have a light!

COLVERT · 21st January 2011, 19:00

Quote:

Originally Posted by Martin75

Cor !!! wish I could understand all those big words and subtle nuances !!

Good luck !! I can't even understand the LITTLE ones.

David Lawrence · 22nd January 2011, 10:07

Wuzerk, you said your stat has a well hidden hole in the rim of the stat plate. I can't see one in mine from Meziere, there's a bit of a mark on the edge of the plate but I can't see light through it. Can you tell me how big a hole I should be looking for.

I'm wondering if this explains the difference between our readings. If mine is totally blocked then it may result in a delay in opening compared with yours. The solution may simply be for me to drill one the size yours is.

I don't suppose Meziere make the stats themselves, they probably buy them in from a variety of suppliers and just put them in their own packaging.

Mintee · 22nd January 2011, 10:26

Quote:

Originally Posted by David Lawrence

Wuzerk, you said your stat has a well hidden hole in the rim of the stat plate. I can't see one in mine from Meziere, there's a bit of a mark on the edge of the plate but I can't see light through it. Can you tell me how big a hole I should be looking for.

Mine is a little 'half-moon' nipped from the edge of the 'stat.

Assemble it in the housening and try pouring water through - you'll soon see if it is really watertight.

David Lawrence · 22nd January 2011, 10:35

Quote:

Originally Posted by Mintee

Mine is a little 'half-moon' nipped from the edge of the 'stat.

Assemble it in the housening and try pouring water through - you'll soon see if it is really watertight.

Thanks for that, I see a "Nip". Do you think that's there by design of a product of how the part is punched out at manufacture? How big is your nip? I poured water in and it does indeed escape. Guess that puts me back to square one in terms of explaining the different performance.

PaulR · 22nd January 2011, 11:34

Well that is service for you!! I ordered the stat yesterday lunchtime, paid for it by credit card and it arrived in the post today. It is beautifully made and makes the plastic fittings in the car look poor indeed!

I fitted it and the temperature increased much more quickly but peaks at about 74 degrees. I could push it higher by doing 70 in 3rd but it dropped again. I was so excited that I just fitted it and didn't check whether the stat has a hole or not. I will buy a QTH107 and try that. Is there any sort of gasket between the flanges of the casing or does it just come apart and go back together again?

I think it will be one of the best £54s I have spent!

Paul

Jules · 22nd January 2011, 11:37

It's an O ring
Be careful re seating it!
QTH 107 are smaller and less flow so just be aware of this.
Same size as Renault stat experiment we tried.
Seen 105C without trying very hard!

PaulR · 22nd January 2011, 11:58

Right, thanKs Jules. When the weather gets a bit warmer I might check the exising stat before I buy anything else. At least the gauge needle now hovers near nine o'clock which is much better than before. It never did that even in the hottest weather.

At a relatively low 60000 miles I would have expected the original stat still to be working well. Maybe I will revert to usng the P4 - nicely balanced cable clutch, thermostat staring you in the face when you open the bonnet, no MAF and suchlike, no electronics or computer - oh and 22mpg hmm....

21st January 2011, 12:31	#882
PaulR Regular poster Rover 75 saloon (and P4 100) Join Date: Oct 2008 Location: Southport Posts: 87 Thanks: 9 Thanked 8 Times in 7 Posts	wow I read this thread more or less from end to end last night (phew I need new glasses!). I always assumed that the pathetic heater on my car was caused by the lack of a FBH but I tried the temperature this morning and it never got any higher that 65 degrees on my 15 mile journey to work. I have just telephoned Specialist Components and they are sending me an in line thermostat. I hope the cold weather lasts long enough to enjoy the warm cab I am now expecting!! As a slight aside, I also run a 1962 Rover P4 100 with a totally analogue capillary water temperature gauge. You can clearly see the movement of the needle on that as the thermostat opens and closes. It never goes out in salty winter weather but it is very interesting on a hot day. The movement of the fuel gauge when you drive round a corner is also something to behold. Paul

21st January 2011, 13:00	#883
Jules This is my second home ZT 260 SE Twilight and 10 other 75 ZT's :O Join Date: Jan 2007 Location: Conwy NORTH WALES Posts: 11,094 Thanks: 512 Thanked 1,116 Times in 763 Posts	Yes Paul give me my analogue gauges of my old triumph Stag any day! Good job Aircraft gauges aren't calibrated like the 75 and most other modern Car Temp gauges Mind at least 75's have a gauge. A lot a small cars now only have a light! __________________ [SIGPIC][/SIGPIC] Newbies do now!! 1. Plenum drains..all 3 or 4 year dependent 2. Cooling fan..All speeds functioning 3. Bonnet cable divider block

22nd January 2011, 11:37	#889
Jules This is my second home ZT 260 SE Twilight and 10 other 75 ZT's :O Join Date: Jan 2007 Location: Conwy NORTH WALES Posts: 11,094 Thanks: 512 Thanked 1,116 Times in 763 Posts	It's an O ring Be careful re seating it! QTH 107 are smaller and less flow so just be aware of this. Same size as Renault stat experiment we tried. Seen 105C without trying very hard! __________________ [SIGPIC][/SIGPIC] Newbies do now!! 1. Plenum drains..all 3 or 4 year dependent 2. Cooling fan..All speeds functioning 3. Bonnet cable divider block

19th January 2011, 19:32	#881
LeRich Posted a thing or two Rover 75 Cont SE 1.8T Join Date: Aug 2010 Location: Cheshire Posts: 1,082 Thanks: 215 Thanked 232 Times in 178 Posts	I've just ordered a QTH107 'stat from Rapid Car Parts for £8 delivered. Hopefully it'll be fitted this weekend assuming it arrives inthe next couple of days. I'm looking forward to seeing what difference it will make to the engine's efficiency and entering the 'club' :lol:

22nd January 2011, 10:07	#885
David Lawrence This is my second home Rover 75 CDT-2001 Join Date: Jan 2009 Location: Wrexham, North Wales Posts: 3,606 Thanks: 195 Thanked 606 Times in 501 Posts	Wuzerk, you said your stat has a well hidden hole in the rim of the stat plate. I can't see one in mine from Meziere, there's a bit of a mark on the edge of the plate but I can't see light through it. Can you tell me how big a hole I should be looking for. I'm wondering if this explains the difference between our readings. If mine is totally blocked then it may result in a delay in opening compared with yours. The solution may simply be for me to drill one the size yours is. I don't suppose Meziere make the stats themselves, they probably buy them in from a variety of suppliers and just put them in their own packaging.

22nd January 2011, 11:34	#888
PaulR Regular poster Rover 75 saloon (and P4 100) Join Date: Oct 2008 Location: Southport Posts: 87 Thanks: 9 Thanked 8 Times in 7 Posts	Well that is service for you!! I ordered the stat yesterday lunchtime, paid for it by credit card and it arrived in the post today. It is beautifully made and makes the plastic fittings in the car look poor indeed! I fitted it and the temperature increased much more quickly but peaks at about 74 degrees. I could push it higher by doing 70 in 3rd but it dropped again. I was so excited that I just fitted it and didn't check whether the stat has a hole or not. I will buy a QTH107 and try that. Is there any sort of gasket between the flanges of the casing or does it just come apart and go back together again? I think it will be one of the best £54s I have spent! Paul

22nd January 2011, 11:58	#890
PaulR Regular poster Rover 75 saloon (and P4 100) Join Date: Oct 2008 Location: Southport Posts: 87 Thanks: 9 Thanked 8 Times in 7 Posts	Right, thanKs Jules. When the weather gets a bit warmer I might check the exising stat before I buy anything else. At least the gauge needle now hovers near nine o'clock which is much better than before. It never did that even in the hottest weather. At a relatively low 60000 miles I would have expected the original stat still to be working well. Maybe I will revert to usng the P4 - nicely balanced cable clutch, thermostat staring you in the face when you open the bonnet, no MAF and suchlike, no electronics or computer - oh and 22mpg hmm....