S70 Coolant Advice Needed

Primo · Post by **Primo** » 23 May 2005, 21:06

Okey I recently bought a used '99 S70 non turbo and so far I've had to do some minor repairs here and there. Not had any major problems yet but just yesterday, the little red radiator looking light on the dash came on and and I thought it would go off by just topping of the tank with coolant. So I went to advanced auto and bought there 50/50 pre mix antifreeze/coolant and was told it wouldn't hurt the car. But after topping off the coolant tank, the light is still on when I start the car and stays on. Is there any a way to reset it because, I just don't feel to confortable driving aroung with the light on. Did I have to use volvo coolant? I have no idea when the coolant was flushed and I guess that's probably what I need to do at this point anyway. Also,I was told by a mechanic today that it might be some kind of "coolant sensor" that has to be replaced

anyone know what that is and it's location??? And honestly, I don't know the exact procedure for flushing the coolant on these volvos. Do I need to use volvo's coolant or any other 50/50 coolant will do just fine for the price. The reason am asking is because I've read somehwere in the owner's manual that only use volvo coolant but if I took my car to any repair shop, am pretty sure they would use something other than volvo antifreeze. Please advice me the way you see it fit and if it's an easy DIY project would you also provide a step by step post or link. Thank you,
+ Primo!!!

White850Turbo · Post by **White850Turbo** » 24 May 2005, 05:29

The main thing that you want to look for on the coolant is that one of the main ingredients is ethylene glycol. As far as the coolant light goes, there is a coolant level sensor in the back underside of the overflow tank. Sometimes, that sensor can vibrate loose from it's original position, causing the system to think that there is less coolant than there really is. Wiggle it around and see if you can get it to work. As for flushing the system, there is a little plastic petcock on the bottom of the radiator that should be used to drain coolant, but make sure that the system is not pressurized first (i.e. the cap is off of the overflow tank).

PRIMO · Post by **PRIMO** » 24 May 2005, 18:06

Thanks 850Turbo...I'll try wiggling it and lets hope that will work. If need be, where else if not dealer can I get the sensor for a good price-any part numbers? So I don't have to use volvo coolant right. Besisds I checked the dealer price almost 20 bucks in my state...damn! Do you think preston 50/50 premix is a good product...thanks!

Jot · Post by **Jot** » 24 May 2005, 18:53

Make sure it is NON phosphorus

Guest · Post by **Guest** » 29 May 2005, 17:12

The main thing that you want to look for on the coolant is that one of the main ingredients is ethylene glycol.

Bad advice. Way incomplete advice.

Just about every antifreeze is ethylene glycol including GM's DeathCool. It is the corrosion inhibitors and other chemicals that make the difference.

Ordinary green ethylene glycol antifreeze, nothing fancy, is good. Zerex G-05 is good. VW's G12 is good. The last two are long life. The first is good for two years, then it needs flushing and renewal to replenish the corrosion inhibitors. The long life antifreezes are probably good for 4 years.

Flush and drain the system (I pull the lower radiator hose and open the petcock on the block to drain). Refill with a gallon of full strength antifreeze and top off with distilled water.

Ken

Zarek · Post by **Zarek** » 06 May 2007, 22:30

why deathcool? name is Dexcool and it works just fine!

Post by **luketrash** » 06 May 2007, 22:43

I've seen dexcool sludge up and plug a lot of heater cores in GM vehicles (can usually be pressure flushed out though..) I think it happens due to dissimilar metals or something like aluminum and brass? That or once it gets too old it breaks down like that. I know mixing green with orange = sludge.

When I flush/fill cars, I usually pull the lower and upper radiator hoses. I pull the thermostat out (and replace it.) That way I can flush the radiator seperately and the engine seperately. I get all the gunk to barf out the bottom of the radiator and engine respectively... HOpefully if the car has been maintained right, there is no stuff barfing out the block.

My Volvo has brown Volvo brand coolant in it right now, and I'll be switching over to the Zerex G5 stuff.

My VW has the original G12 in it from 1998 and seems to be doing A-OK. I'm too lazy to flush it out, since I'll probably sell the car in the next couple of years.

aj98s70 · Post by **aj98s70** » 07 May 2007, 10:05

I would recommend picking up a gallon of Volvo branded radiator fluid from the dealer. You will likely pay 1.5x the price - but for an extra $10 or so you will not have to worry about any ill effects.. My 98 s70 uses a green type of coolant. Your dealer will know based on year what coolant to use.

As far as draining your radiator - there is a petcock on the bottom right (as you look towards the car from the front)..
Make sure the engine is cold.
Do not open the radiator cap off the overflow tank. Put a pail under the radiator block and slowly loosen the petcock. This will start a small trickle.
Now open the radiator cap. The amount flowing out will increase rapidly.
You will likely drain a little more than 1 gallon.
Mix coolant with *distilled* water - 50/50 mixture is usually recommended - the coolant container will have the dilution ratio recommendation based on operating conditions.
After the draining is complete, tighten the petcock. Refill with new mixture.
Run engine with cap off for a little bit. This will get any air bubbles out of the system.
Top off if necessary. Put the cap back on.

Hope that helps..

Post by **Maxbaby** » 07 May 2007, 11:14

Luke... just curious, but what is it about the Zerex that you like? I'm not sure I have seen Zerex around here, so I'll have to "ingredient shop" when I go to flush my system shortly. Do you know which ingredients specifically that I should run away screaming from?...

)

Zarek · Post by **Zarek** » 09 May 2007, 23:14

OK Luke got it but I can tell you that carboxylate technology used in dexcool is the best to prevent corrosion. All truck manufacturers are inisisting on it these days. In cars, the thing is not so critical so you may get by with the green stuff. Reason for the sludge you have see in the GM vehicles is air in the cooling system. If you have pockets of air, which may happen if you have a bad radiator cap, and ferrous materials you may get iron oxide forming in the area where the air poket is; in the GM it will probably be the cylinder heads. Carboxylates only protect against corrosion in a liquid phase and will combine with the iron oxide to form a carboxilic soap, which is the brown sludge you saw- I know because I had it in my 2000 Chevy Blazer and it made a mess of the thermostat, radiator and coolant bottle; I had to replace the radiator. The problem however is not attributable to the coolant but to a poor design of the cooling system, especially the radiator cap. In my two Volvos I have dexcool (I won't touch the green stuff even with a long stick, silica deposits kill your water pump) but Volvo cylinder heads are aluminum and don't usually keep air pockets so the sludge problem is unlikely to happen.