Diesel thermostat definative answer - Page 12

wuzerk · 22nd October 2010, 14:19

No problems with the in-line 'stat installation and,quite frankly, I don't expect any. If the original 'stat stuck in the closed position then it would have to be replaced and nothing i have done has altered that fact. What it has altered is that if you have a 'stat which opens too early then you can just ignore it and leave it in situ because the temperature will still be controlled by the new,higher rated one which is fitted closer to the radiator in an easily accessible position. If the new unit did fail it would only be important if it stuck closed. In that case the in-line stat housing could be removed completely by undoing two hose clips and replacing with a suitable piece of pipe. I say use pipe because the housing has two spanner fittings which are approximately 2 1/2" across the flats! Not a size you are likely to be carrying in the boot if you wanted to fit another
Thermostat by the roadside. What a thought....change a diesel 75 thermostat in minutes by the roadside!
The OBD running temperatures are from 87C to 93C and are entirely dependent on the load on the engine.

Jakg · 22nd October 2010, 17:34

Any chance of a how to etc happening soon?

Matt1960 · 22nd October 2010, 18:03

Quote:

Originally Posted by Jakg

Any chance of a how to etc happening soon?

I think its as simple as cut a small section out of the top hose, put the housing in and seal with jubilee clips. Top up. About 10 mins, I would guess. Or am I being too simplistic here?
Matt

Jules · 22nd October 2010, 18:33

Quote:

Originally Posted by wuzerk

No problems with the in-line 'stat installation and,quite frankly, I don't expect any. If the original 'stat stuck in the closed position then it would have to be replaced and nothing i have done has altered that fact. What it has altered is that if you have a 'stat which opens too early then you can just ignore it and leave it in situ because the temperature will still be controlled by the new,higher rated one which is fitted closer to the radiator in an easily accessible position. If the new unit did fail it would only be important if it stuck closed. In that case the in-line stat housing could be removed completely by undoing two hose clips and replacing with a suitable piece of pipe. I say use pipe because the housing has two spanner fittings which are approximately 2 1/2" across the flats! Not a size you are likely to be carrying in the boot if you wanted to fit another
Thermostat by the roadside. What a thought....change a diesel 75 thermostat in minutes by the roadside!
The OBD running temperatures are from 87C to 93C and are entirely dependent on the load on the engine.

Well done on this Wuzerk.
Like you say the worst that can happen is the new one fails closed, even then I believe there would be plenty of warning
ie visible steam, then an even bigger delay before any serious damage to the hot lump.

Quote:

Originally Posted by Matt1960

I think its as simple as cut a small section out of the top hose, put the housing in and seal with jubilee clips. Top up. About 10 mins, I would guess. Or am I being too simplistic here?
Matt

28 mins Wuzerk states !

T-Cut · 22nd October 2010, 22:10

Quote:

Originally Posted by Jules

Like you say the worst that can happen is the new one fails closed!

And this applies equally to ALL thermostats in ALL engines. I've yet to read of it happening on these cars and the Americal unit is no different. I think worrying about the possibility of a stuck shut stat is being over cautious about applying the mod. So far it looks like a great advance in getting the diesel closer to the optimum band in both heating efficiency and fuel economy. If I had a diesel, I'd be odering the parts already. Personally, I think I'd now try it without the pin hole.

TC

wuzerk · 22nd October 2010, 22:21

Yes, it is rare that such a useful modification is so easy to fit once you have summoned the nerve to cut the pipe! Points to note:
1.Use plastic sheet to prevent water hitting the Alternator when you cut the pipe.
2.It is probably sensible to remove the undertray because otherwise the water sits there and, in the middle of your test run, you suddenly see steam wafting from the grill causing panic until you realise what is happening. OR, follow Jules advice (below) re lowering the expansion tank.
3. Be sure to install the Thermostat the right way round. The wax housing, with '195' stamped on it, should face the engine block.
4.It is hard to fit the 1 1/2" stub into the sawn pipe on the engine block
side but washing up liquid helps and, once in, it is very snug and there
is no need for any sort of support bracket.
5. The other cut should be made so that you have enough of the
straight hose pipe left to engage the end of the 'stat housing without
involving the bend in the top hose.
6. Much to my surprise, with the radiator cap fitted, I only lost just over
a litre of coolant when I cut the pipe. So have your 50/50 mix of OAT
antifreeze ready. OR follow Jules suggestion (below).
7. The spanner flats on the housing are approx. 2 1/2" across! If you
have the facilities is would be worth making up a couple of sheet metal
'spanners' to carry in the boot together with a spare Thermostat. This
would mean that, if necessary, you really could change the diesel stat
on the side of the road! If not, I would carry a suitable 4" length of tube
which would replace the entire housing if necessary. An exhaust
centre would probably supply a piece of stainless?
8. I have no idea of the reliability of the Chevrolet stat, but imagine they
know what they are doing in the USA and I am sure one of us will find
an alternative if it proves necessary.
9. For those of you with underperforming 'stats, hurry up, winter is nearly
here!
NOTE: I used a stat housing with 1 1/2" hose fittings. The diesel top hose is tapered and the 1 1/2" stub was
almost impossible to fit in the radiator side of the cut pipe. You need 1 1/2" at the engine block end and
1 1/4" at the rad end. There is no part number for this configuration but the supplier says just let him know
and that the price will be the same. The suppliers e-mail is [email protected] and the website is:
http://www.meziere.com/displaycategory.aspx?id=244,323

Uploaded with ImageShack.us

Uploaded with ImageShack.us

I HAVE INCLUDED THE PICS AGAIN FOR THOSE WHO MISSED THEM EARLIER.

NOTE: There IS a well hidden bleed hole in the rim of the thermostat plate so there is no need to drill any new bleed holes. This mod gets simpler every
time I look at it!

wuzerk · 22nd October 2010, 22:25

I would agree with TC re the 1mm hole which I drilled to remove the chance of an air lock. it is worth fitting the Chevvy stat as it comes, with no hole. If an air lock does occur then i think the problem will resolve itself as soon as the 'stat opens the first time?
EDIT: There IS a well hidden hole in the thermostat valve plate so there is no need to make another one.

Jules · 22nd October 2010, 22:33

Trouble is it will probably cause a price hike when USA get a sudden surge of orders !! So don't all rush at once.
Another reason to have a proper Club Shop to have a bulk buy.

My advice is not to loose any coolant.
Simply loosen the 8mm bolt on the header tank and lower it next to the Battery so you can syphon off the excess, then pour it back in when job complete.

Don't forget Gents a stuck closed Stat will never be as bad as an actual water leak (hence low coolant level round the block) as there will be plenty of warning in the way of steam, without engine damage

sof007 · 26th October 2010, 10:29

Is anyone considering a bulk buy??

Should we see if people are interested.

Jules · 26th October 2010, 11:11

Chaps
I'm waiting on a bulk quote from them.

22nd October 2010, 14:19	#111
wuzerk Passed Away Rover 75 CDT 03 auto Conn. SE Join Date: May 2009 Location: London Posts: 2,885 Thanks: 104 Thanked 254 Times in 204 Posts	Update No problems with the in-line 'stat installation and,quite frankly, I don't expect any. If the original 'stat stuck in the closed position then it would have to be replaced and nothing i have done has altered that fact. What it has altered is that if you have a 'stat which opens too early then you can just ignore it and leave it in situ because the temperature will still be controlled by the new,higher rated one which is fitted closer to the radiator in an easily accessible position. If the new unit did fail it would only be important if it stuck closed. In that case the in-line stat housing could be removed completely by undoing two hose clips and replacing with a suitable piece of pipe. I say use pipe because the housing has two spanner fittings which are approximately 2 1/2" across the flats! Not a size you are likely to be carrying in the boot if you wanted to fit another Thermostat by the roadside. What a thought....change a diesel 75 thermostat in minutes by the roadside! The OBD running temperatures are from 87C to 93C and are entirely dependent on the load on the engine. Last edited by wuzerk; 22nd October 2010 at 14:35..

22nd October 2010, 22:21	#116
wuzerk Passed Away Rover 75 CDT 03 auto Conn. SE Join Date: May 2009 Location: London Posts: 2,885 Thanks: 104 Thanked 254 Times in 204 Posts	In-Line Stat. Yes, it is rare that such a useful modification is so easy to fit once you have summoned the nerve to cut the pipe! Points to note: 1.Use plastic sheet to prevent water hitting the Alternator when you cut the pipe. 2.It is probably sensible to remove the undertray because otherwise the water sits there and, in the middle of your test run, you suddenly see steam wafting from the grill causing panic until you realise what is happening. OR, follow Jules advice (below) re lowering the expansion tank. 3. Be sure to install the Thermostat the right way round. The wax housing, with '195' stamped on it, should face the engine block. 4.It is hard to fit the 1 1/2" stub into the sawn pipe on the engine block side but washing up liquid helps and, once in, it is very snug and there is no need for any sort of support bracket. 5. The other cut should be made so that you have enough of the straight hose pipe left to engage the end of the 'stat housing without involving the bend in the top hose. 6. Much to my surprise, with the radiator cap fitted, I only lost just over a litre of coolant when I cut the pipe. So have your 50/50 mix of OAT antifreeze ready. OR follow Jules suggestion (below). 7. The spanner flats on the housing are approx. 2 1/2" across! If you have the facilities is would be worth making up a couple of sheet metal 'spanners' to carry in the boot together with a spare Thermostat. This would mean that, if necessary, you really could change the diesel stat on the side of the road! If not, I would carry a suitable 4" length of tube which would replace the entire housing if necessary. An exhaust centre would probably supply a piece of stainless? 8. I have no idea of the reliability of the Chevrolet stat, but imagine they know what they are doing in the USA and I am sure one of us will find an alternative if it proves necessary. 9. For those of you with underperforming 'stats, hurry up, winter is nearly here! NOTE: I used a stat housing with 1 1/2" hose fittings. The diesel top hose is tapered and the 1 1/2" stub was almost impossible to fit in the radiator side of the cut pipe. You need 1 1/2" at the engine block end and 1 1/4" at the rad end. There is no part number for this configuration but the supplier says just let him know and that the price will be the same. The suppliers e-mail is [email protected] and the website is: http://www.meziere.com/displaycategory.aspx?id=244,323 Uploaded with ImageShack.us Uploaded with ImageShack.us I HAVE INCLUDED THE PICS AGAIN FOR THOSE WHO MISSED THEM EARLIER. NOTE: There IS a well hidden bleed hole in the rim of the thermostat plate so there is no need to drill any new bleed holes. This mod gets simpler every time I look at it! Last edited by wuzerk; 24th October 2010 at 19:35..

22nd October 2010, 22:25	#117
wuzerk Passed Away Rover 75 CDT 03 auto Conn. SE Join Date: May 2009 Location: London Posts: 2,885 Thanks: 104 Thanked 254 Times in 204 Posts	Stat hole I would agree with TC re the 1mm hole which I drilled to remove the chance of an air lock. it is worth fitting the Chevvy stat as it comes, with no hole. If an air lock does occur then i think the problem will resolve itself as soon as the 'stat opens the first time? EDIT: There IS a well hidden hole in the thermostat valve plate so there is no need to make another one. Last edited by wuzerk; 26th October 2010 at 13:35..

22nd October 2010, 22:33	#118
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	Trouble is it will probably cause a price hike when USA get a sudden surge of orders !! So don't all rush at once. Another reason to have a proper Club Shop to have a bulk buy. My advice is not to loose any coolant. Simply loosen the 8mm bolt on the header tank and lower it next to the Battery so you can syphon off the excess, then pour it back in when job complete. Don't forget Gents a stuck closed Stat will never be as bad as an actual water leak (hence low coolant level round the block) as there will be plenty of warning in the way of steam, without engine damage __________________ [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

26th October 2010, 10:29	#119
sof007 Avid contributor MG ZT Join Date: Aug 2010 Location: Galway Posts: 194 Thanks: 0 Thanked 1 Time in 1 Post	Is anyone considering a bulk buy?? Should we see if people are interested. __________________ MG ZT CDTi 135+ Trophy Blue 131,000 and rising

22nd October 2010, 17:34	#112
Jakg This is my second home N/A Join Date: Feb 2010 Location: Suffolk Posts: 6,867 Thanks: 0 Thanked 397 Times in 302 Posts	Any chance of a how to etc happening soon?

26th October 2010, 11:11	#120
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	Chaps I'm waiting on a bulk quote from them. __________________ [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