Antifreeze and cooling questions

[RuffianDick]

Hello,

We're gonna be taking our R4 through some seriously hot places on the mongol rally (it can get over 50 C in Turkmenistan :eek so i've been looking for some tips to avoid (or at least reduce) overheating problems.

One thing that i've seen mentioned is to flush out the radiator and cooling system to make sure its all working as effciently as possible. So i've got some Holts RadFlush - my first question is do I need to use a certain type of antifreeze when i fill her back up?

The stuff in the expension bottle is a nasty rust colour - i dont know if it was originally orange or whether that is purely rust!

Secondly - does anyone have any other tips for us? We were thinking of fitting a second radiator fan. Think this would help?

Cheers
Rich

 

[F6frogie]

Hi, you would definately need to fit some sort of second fan on a seperate switch on your dash (you need as much air flowing through your rad as much as you can. I even have an overide switch for my standard fan for security.

You will also need a good quality water temp gauge kit and have the sender installed towards the rear of the head (near the screen) which is the hottest part (actually reading the head temp/not water).

regarding the antifreeze - if it's brown then it's most proberly rust (could also be a headgasket bust most likely cause is rust).
If I were doing the rally, I'd flush the system out properly (removing all hoses, rad, and heater matrix and manually flush them out rigoursly with water (change any worn items, hose, rads, clamps, pump - I would change most of these for the rally just for piece of mind) - then re-fit (I would leave the thermostat out) , remove one of you hoses which goes to your interior heater matrix at the pump end, attach a garden hose and flush out for several minutes. then I would use a flush (or several flushes) to get it really clean and refill with a good antifreeze, not for it's anti freezing properties but for it's anti rusting agents - then don't forget to bleed the system properly.

Remeber to also test your warning switch and fan switch to see if they function properly and that the fan comes on at the correct time.

 

[reidalpine]

Small tip if you see temp rising-Turn ON the heater to get some extra circulation in there-Very hot for the tootsies but it helps keeping the temp.under critacal point of overheating.
If you could make some sort of vent/scoop (ex.to the rear of the bonnet) you will get much improved blow-through in the engine-compartment..
Not a pretty sight maybe-but I'd rather go blind than have to call
AA(recovery) from Mongolia!!
also make sure the engine runs a tiny bit rich rather than lean as lean is mean when it comes to temp..
You will need glycol-based(approved for Aluminium)antifreeze and do not mix to higher degree than what is said on the bottle as you might get better anti rust vice,but a worsening re.overheating
would also bring Coke (Coca Cola That is!) the real one WITH sugar nothing betters it if the cluch overheats and starts to slip
pour Coke on the clutch and the sugar will crystalize and stick to the plate and off you go again! Ordinary Cinnamon (powder) is a real miracle-medicine for leaks in the radiator.Pour in at top of rad
Careful if hot!! or into expansion-bottle It will not clog the system
but goes a long way in fixing leaky rads.
Last tip; Ordinary piece of soap (can also be used to wash human bodies-This I have from my wife!) If petroltank develops a leak
soak soap in water to soften it then RUB in and around hole or crack in tank-Some weird chemical reaction makes it react with petrol to temporarely stop leak... -R.

 

[RuffianDick]

Absolutely brilliant advice there guys, thank you both

Funny you should mention the bonnet scoop, we were actually looking at them on ebay recently, more as a comedy mod than a practical one, maybe we'll actually consider it for real now.

There is one other problem with trying to get as much air around the engine though - some places are going to be super dusty. I guess engines dont like being filled with dust too much!

So any advice on protecting certain critical areas of the engine from dust/sand/grit etc?

 

[reidalpine]

Hi there Mong(R)ols! -personally I would def. go for a pre-oilbath Airfilter if you can find one-This is an extra cylindrical box where intake-air is sifted throught oil then into the actual airfilter..
Main thing is to keep airfilter clean at all times-make a habit out of taking it out At least Every night and clean it well-also I would spray it with some light oil for that use (Green-filters and others sells oil for filterelement. Don't know how well oil will work on ordinary wicked paperelement filters-as it might restrict airflow through..
Wouldn't worry about dust and such on engine as long as you get rid of it at night so it won't build up too much

'Wax it on-Hose it off' a Free Frank Zappa-saying for you.
'nother means of keeping the under-bonnet temp as low as poss.would be to wrap exhaust-header and pipe under bonnet with
exhaust-bandage It makes the exhaust leave the system at higher velocity and helps engine breathe (scavenging-effect) BUT....If you go for such bandage it is ABSOLUTELY VITAL that NO oil or gas can leak onto it-The bandage will not burn by itself but mixed with gas
or oilsmear (or even coolant)it will burn fast and furiuos...
If you go for a top-of bonnet scoop or vent I would've used one that SUCKS hot air out at rear.If you mount it forward-facing I would think it could build up an air-buffer in there to further reduce the inflow via the front-grille. I gather down at your local charityshop you might find a jurrassic computer (pre-04) rip out the 12V fan
usually 12x12 cm mount it under the scoop (it will only work in one
direction but you can turn it other side up) 2 simple wires (+ Fuse!) and you can turn it on to suck even more air out via the scoop.
It uses No current at all-compared to ordinary fans so can be left on all day & night..
Make sure the valvecower are secured so not to suck it out too. c",)

 

[angel]

In addition to what Reidalpine said, I would add that on poor road R4s an "anti-sable" (sand-proof) distributor was fitted, nothing more than a plastic cover between the rotor arm and distributor body. I don't know if it is really effective (or if your dizzy is already fitted with this).

 

[seujimmy]

I can reccomend Redline water wetter ( there are other makers). This is a addative that you add to your coolant . It says it will reduce the coolant temerature buy up to 15 C . It certainly worked for my kikcar reduceing the temperature by 10 C which with the radiator inside the car was a god send in summer. It works by stopping the formation of air bubbles sticking to the walls of the water jacket or so they say. Its like the stuff you put in to the cental heating system to stop it kettleing.

 

[angel]

Had put WaterWetter once in my '75 845 which had its head already skimmed by 0,4mm (=a little highter temperatures), and it seemed to work.

 

[merlody]

about what u said: The stuff in the expension bottle is a nasty rust colour - i dont know if it was originally orange or whether that is purely rust!

i've a little advice that i do myself
1. remove and empty the bottle
2. fill it with some sand ( very small quantity )
3. add water about 1/3 the bottle or something, but close the outlet port with ur fingure
4. close the bottle and shake it with ur hands

the sand and water will now remove the rust sticked on the walls, the more u shake the more rust is removed
now empty the bottle and clean it with water and enjoy the brighter colour the standard bottle is not that pure white color; it's a bit yellow
hope i may have helped u