PRT or leave as is? opinions requested please - Page 3

T-Cut · 3rd September 2013, 20:51

Quote:

Originally Posted by chipsceola

There may however be a case for lowering the OAT anti-freeze concentration from 50/50 to 35/65 or - - - -

There are several (probably misunderstood) reasons behind this. The primary one is the historical fallout from the infamous class action against General Motors and their OAT antifreeze 'DexCool'. Associated concerns relate to the 'dissolving' of rubber gaskets used in the 75/ZT range of engines as well as the apparent attack of silicone hoses and the like.

The scientific reason behind this is well understood and is invariably associated with poorly managed and badly maintained cooling systems. When coolant is lost, and what's left is allowed to repeatedly overheat, over time, the OAT reacts chemically with ethylene glycol to produce plasticiser-like byproducts. Under adverse conditions, these products will soften polymers like synthetic rubber and silicones. The evidence produced during the DexCool investigations demonstrate it. So, if you don't want to adopt a good maintenance plan, don't use OAT. With proper servicing and maintenance routines, red OAT/Glycol and the upcoming purple OAT/Glycerine formulas are fine. Most car producers now specify OAT of one type or another at 50% concentration. They wouldn't do so if it wrecked engines. As a chemist, I'm not convinced that reducing the OAT concentration has a significant effect on the process described under the conditions described. Even in plain tap water the OAT actives will degrade under the conditions described above.

My 1.8T has always had 50% OAT and at the moment contains DexCool from the local Vauxhall depot.

TC

T-Cut · 3rd September 2013, 20:58

Double post.

chipsceola · 4th September 2013, 15:05

Thanks T-Cut once again, a 10 year old car with mostly original hoses is a point of concern and tales of OAT damage don't help the situation. But you can't change everything under routine or preventative maintenance as not practical proposition,.

When I posed this question (HOSES) posts came back telling of parts over 20 years old still being serviceable with blue AF mix, knowing or being aware that sticking to /or exceeding coolant change schedule should help in this respect does give a certain peace of mind to the problem.

When you think about it, even 10/13 years is a long time and am sure there are lots of 75/ZTs like mine still running OEM hoses, and apart from a visual inspection, I haven't found anybody changing them as routine practice.

WillyHeckaslike · 5th September 2013, 11:38

The black and the cream PRT as originally manufactured were not designed for the K-Series, the grey PRT is but it wasn't available until 2005. Although the grey PRT entered service just after Rover's demise Rover oversaw its design and development, use of both a lower stat and spring rating won't have been taken lightly.

I believe that cold fuelling is switched off completely around 70c so it won't be affected by the lower stat rating.

ashbash2403 · 5th September 2013, 17:41

I have a new grey 82 deg prt to fit after reading numerous discussions on them. Had to change my t piece to prt hose anyway due to small split so good time to add another cooling system strengthener

3rd September 2013, 20:58	#22
T-Cut This is my second home Rover75 and Mreg Corsa. Join Date: Nov 2006 Location: Sumweer onat mote o'dust (Sagin) Posts: 21,754 Thanks: 341 Thanked 3,660 Times in 2,924 Posts	Double post. Last edited by T-Cut; 5th September 2013 at 16:17..

4th September 2013, 15:05	#23
chipsceola This is my second home Jaguar XF 3.0D Join Date: Nov 2010 Location: Southampton Posts: 4,364 Thanks: 119 Thanked 509 Times in 426 Posts	Thanks T-Cut once again, a 10 year old car with mostly original hoses is a point of concern and tales of OAT damage don't help the situation. But you can't change everything under routine or preventative maintenance as not practical proposition,. When I posed this question (HOSES) posts came back telling of parts over 20 years old still being serviceable with blue AF mix, knowing or being aware that sticking to /or exceeding coolant change schedule should help in this respect does give a certain peace of mind to the problem. When you think about it, even 10/13 years is a long time and am sure there are lots of 75/ZTs like mine still running OEM hoses, and apart from a visual inspection, I haven't found anybody changing them as routine practice. __________________ Chips

5th September 2013, 17:41	#25
ashbash2403 Loves to post MG ZT 1.8T 160 Xpower Grey Join Date: Jul 2010 Location: Aldridge Posts: 355 Thanks: 8 Thanked 15 Times in 15 Posts	I have a new grey 82 deg prt to fit after reading numerous discussions on them. Had to change my t piece to prt hose anyway due to small split so good time to add another cooling system strengthener __________________ You don't need to own a sheep to know what not to put in it !

5th September 2013, 11:38	#24
WillyHeckaslike This is my second home Rovers 75 & 25 Join Date: Oct 2010 Location: Wearside Posts: 4,572 Thanks: 543 Thanked 709 Times in 511 Posts	The black and the cream PRT as originally manufactured were not designed for the K-Series, the grey PRT is but it wasn't available until 2005. Although the grey PRT entered service just after Rover's demise Rover oversaw its design and development, use of both a lower stat and spring rating won't have been taken lightly. I believe that cold fuelling is switched off completely around 70c so it won't be affected by the lower stat rating.