Reliant Scimitar overheating.

[rich.]

I was told that the rad was new.

Bob

we have all been had by people like that..

[tractorman]

VWs use 50-50 or their own antifreeze when filling a system and 100% for topping up - and say it never needs changing!! It certainly didn't harm the last (mkIV) Golf; I don't think I used a litre in the five years I owned it.

I read somewhere that the Prima engine (diesel version of the "O" series) should have 50% as it prevents problems around no4 cylinder.

33% gives protection to -18 deg C; we had -15 three or four years ago; 30% would have turned to slush in that!

[JPB]

Hmm, no way I'd risk 50% in an engine that's in use. I've seen an internal view from an endoscope in a test engine that shows the coolant beading like the rain on a waxed panel at that sort of concentration.

http://esource.alstribology.com/WB033_N ... Eckert.pdf

[Cambronne]

There's another tweak that proved useful. Later Essex V6's had a thermostat housing with a cap and bleed pipe connection. I fitted one of these and connected the bleed pipe to a Marina expansion bottle mounted as high as possible in the engine bay.

This let the system blow back when the engine was stopped, and the expelled water could drain back in as the engine cooled. I could even bleed air from the heads with the engine cold, by gently opening the 'stat with a thin screwdriver.

The stat's housing obviously had a plain rad cap...the pressure cap went on the expansion bottle.

[TerryG]

I use 50% in my range rover as it says to in the manual. Until a few years ago that was doing 500 miles a week, no issues. Same for my modern fords, they do tens of thousands of miles a year and no problems.
I have debated switching to waterless coolant with the larger rover v8s reputation for dropping liners (caused by overheating). Modern stuff I care less but the coolant gets changed annually, so does the brake fluid, oil bi-annually.

[History]

I was under the impression that even at 90% antifreeze the coolant has the same cooling capacity as water.
I shall check. The Reliant instructions say 50%.

The scimitar was around for quite a few years. I should think that Reliant knew what they were doing. So my thoughts are that if the correct parts are used then it should be ok. I will check the water pump pulley for being the correct part. I will hide the fan and other bits under the spare wheel area so that the engine area looks std.

It's all to easy when cars go wrong and its not obvious to think that the design is wrong.

For those who fancy a scimitar. These cars are quite simple cars. They have a reputation for dodgy electrics this is simple to put right with decent earth straps. The trim is poorly made. Even so I was surprised at how cheap they are.


Bob.

[JPB]

Bob, all of the answers to the points where you've been a victim of misinformation are contained in the link. Incidentally, I'm looking at the advice in the Blue bound factory manual (SE5/5A) now, it states that only in "Arctic" conditions and then only as a temporary measure is [MEG] to be used at more than the correct 33% maximum.
Read the data contained in that document. I could have sat here and put up all of that myself in a reassuringly long post that you'd have disregarded in any case, but elected instead to use a paper that's recognised industry wide and gets there in fewer words.

I will just mention the part which points out that - regardless of manufacturer's recommendations - MEG-based coolant additives and others become potentially extremely damaging at as little over the 50% as a further 10% of the original volume since their inability to make full contact is yet another cause of cavitation, have you tested the SG of what's already in there yet?

[History]

JBP.
The af in the car has been dumped.

My knowledge of antifreeze is minimal I know about hoat and oat antifreezees. Which is about it. I rely on what the book says. However once I get curious I go deep.

Both my cars the other being a jeep say 50%. But I run at 25 to 35%. Because I know that the anti corrosion additives will be enough and where I live freezing below zero is very rare.

I know what customers are like they top up with plain water.

I am a professional mechanic which means I must follow what the book says. I cannot do something else unless I can explain with proper valid reasons.

I shall let you know what I find out about the secret life of antifreeze. I shall check out bob the oil guy first. And then hit the makers sites. I will then bore the snot out of everybody with my new found antifreeze knowledge.

Incidently neither of my cars use coolant. They have been very good

I always remember that so many things to do
with cars aren't what they seem.
But first I have apple crumble and custard to eat.

Bob.

[Classic Microcars]

What you need to remember is that there is no more efficient coolant than plain water. If it were not for the corrosion and freezing / boiling points, it would be perfect. So the idea is that you add as little antifreeze as you need to and 33% is about right. Any more than that and you are reducing cooling efficiency.

You have been directed to the source of expert advice, you really should visit.

[Flatlander]

...I have debated switching to waterless coolant with the larger rover v8s reputation for dropping liners (caused by overheating)...

I'm using Waterless coolant in two of mine. First was in the bike a couple of years ago, and now in the restos engine. I can pass on a couple of first hand opinions if desired.