MEG or OAT coolant?

[Rich H]

Hello again,

I'm getting my moneys worth in here

Is there any difference in performance between MEG or OAT coolant?

I assume that it would originally have been MEG but as I'm hoping to purge the lot I could use OAT - any advantages or problems?

Many thanks

Rich

[red vtec]

I read that OAT rots the seals on older cars.

[Bibs]

I've never heard that to be honest, rubber hasn't changed in the last few years and seals are seals.

OAT is better than the blue stuff, it's just newer and better technology which isn't as corrosive so lasts longer. For peace of mind you can still change it as often should you wish and you'll notice it comes out cleaner than blue.

[mr.oogieboogie]

when i asked peter smiths and they reccomended the usual blue stuff,

[Bibs]

The technical dept at Lotus Cars on 01953 608000 will recommend the pink stuff. I've called them and asked before, Dave Massey recommended it over the blue.

[arbell9]

We had a discussion on OATs v blue PEG in the thread on puk chargecooler impeller. IIRC the oat could soften the polyurethane in theory. But the stock one is rubber so it would not have any effect. OAT seems to be the choice for most manufacturers today. I think there will be negible difference in performance given that the coolent is swapped fairly freequently. And by performance i mean wear and tear and the amount of crud genereated im thr fluid. Having old rads and pipes etc contributes to that more than the coolent i think.

[Rich H]

I have 4 litres of MEG blue and that's what's in it so I'll use that - thanks!

Drained the coolant today could only get to the top rad hose though on the RHS. Drain plug was hidden by the undertray which was of course stuck fast. Flushed with plenty of water but it was nice and clean coming out. the expansion tank was prety nasty though so I suspect it's not run long enough to get the thermostat open properly adn circulate the coolant in the front.

Going to get the main coolant tank out and clean it out with something and keep flushing until I'm happy it's all changed.

Got the chargecooler off and flushed it too. The bleed screw was a bit tight but the lekky rattle gun shifted it.

Should the expansion tank (Under the LHS rear wing) have a pressure cap on it? This one seems to have a plain cap with a rubber seal?

Edited August 2, 2010 by Rich H

[Simon350S]

If you want to flush the whole lot thoroughly why not pop out the thermostat? Its easy to get to and my well be worth changing anyhow as a matter of course?

Theres a good chance your header tanks is quite badly corroded. If its not completely perforated now would be a VERY good time to give it a significant clean up and paint with something substancial, POR15 for example, may last a good few more years with that treatment.

Get rid of your chargecooler pump and replace it with an electric one, they are the future, if you do not, EVERY time you have to replace the impellor you will curse yourself for not sorting it out sooner!!!!

Have fun with her matey

[Rich H]

I've been considering the electric pump but I'm going to repair as is, think of all that extra weight!!

I'll pop the t-stat I assume it's a standard issue part? Got a few bits to trace will go and bother the Lotus Dealer on Preston docks - should test them nicely....

The tank is plastic - it's just filthy, if I had a dishwasher it'd get a cycle but I don't think the washing machine will have the same effect....