1985 Coolant to use
Thread Starter
Drifting
Joined: Mar 2017
Posts: 1,897
Likes: 165
From: Nashville TN
2017 C4 of Year Finalist
1985 Coolant to use
I looked in the coolant reservoir and it looks like the previous owner might just have put water in, but I'm not sure. I was thinking of putting the "add to any coolant" stuff in just in case, since I don't know what might be in there. Would that be ok?
I suppose I should honestly do a flush, but it's cold outside and not sure I want to do that right now.
I suppose I should honestly do a flush, but it's cold outside and not sure I want to do that right now.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
Did you check the coolant level in the radiator? Remove the cap and check there. The coolant level should be at the top of the filler neck.
What color is the coolant in the radiator? It should be a bright green. That would indicate the coolant is ethylene glycol and you should continue to use that coolant in a 50-50 mixture. Top off the level in the radiator and then drain the overflow tank and fill to the Cold mark with the same mix.
Any indication of cooling leaking anywhere?
What color is the coolant in the radiator? It should be a bright green. That would indicate the coolant is ethylene glycol and you should continue to use that coolant in a 50-50 mixture. Top off the level in the radiator and then drain the overflow tank and fill to the Cold mark with the same mix.
Any indication of cooling leaking anywhere?
Oil Producer
Joined: Apr 2014
Posts: 9,372
Likes: 2,736
^^^
and if your overflow tank is disgusting, grab a couple handfuls of nearby playground gravel, clean it, but sticking it in a large bowl and the organics will float to the top. then pour them in the overflow container with a bunch of hot soapy water suds. keep shaking/agitating and they will scrub your overflow container to look clean like new.
removing and replacing the overflow is very easy. if your overflow tube looks like has cracks in it, usually where it meets the tank nipples, then replace it with a 1$ piece of hose.
and if your overflow tank is disgusting, grab a couple handfuls of nearby playground gravel, clean it, but sticking it in a large bowl and the organics will float to the top. then pour them in the overflow container with a bunch of hot soapy water suds. keep shaking/agitating and they will scrub your overflow container to look clean like new.
removing and replacing the overflow is very easy. if your overflow tube looks like has cracks in it, usually where it meets the tank nipples, then replace it with a 1$ piece of hose.
Melting Slicks
Joined: Jul 2005
Posts: 2,649
Likes: 863
The 1985 came with the Green Ethylene Glycol coolant. Unless someone changed it to the orange Dex Cool stuff - the green stuff that is still far more readily available (???) and is what you want.
IMHO - the pre-diluted stuff is a waste of money - get the concentrate and a gallon of Distilled Water - especially if you're planning to do a full flush later on.
IMHO - the pre-diluted stuff is a waste of money - get the concentrate and a gallon of Distilled Water - especially if you're planning to do a full flush later on.
Safety Car
Joined: Jun 2006
Posts: 4,007
Likes: 1,488
From: Ashland, OH
The 1985 came with the Green Ethylene Glycol coolant. Unless someone changed it to the orange Dex Cool stuff - the green stuff that is still far more readily available (???) and is what you want.
IMHO - the pre-diluted stuff is a waste of money - get the concentrate and a gallon of Distilled Water - especially if you're planning to do a full flush later on.
IMHO - the pre-diluted stuff is a waste of money - get the concentrate and a gallon of Distilled Water - especially if you're planning to do a full flush later on.
Thread Starter
Drifting
Joined: Mar 2017
Posts: 1,897
Likes: 165
From: Nashville TN
2017 C4 of Year Finalist
Thanks for the advice guys-yeah I NEVER get the pre-diluted stuff.
I'm going to definitely be flushing the coolant soon. I drained the radiator and added ethylene glycol as you stated, and it drained out some brown sludge. I'm hoping that's not indicative of damage to the engine, but first warm day I get I'll be flushing this thing properly.
I just had to get some antifreeze into the system for now, because we're getting 20 degrees at night and I didn't want to wake up to a cracked radiator from ice.
I'm going to definitely be flushing the coolant soon. I drained the radiator and added ethylene glycol as you stated, and it drained out some brown sludge. I'm hoping that's not indicative of damage to the engine, but first warm day I get I'll be flushing this thing properly.
I just had to get some antifreeze into the system for now, because we're getting 20 degrees at night and I didn't want to wake up to a cracked radiator from ice.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
You didn't mention the condition of the radiator hoses, but when you do the flush, I would recommend that you replace both of those hoses. Can't hurt to get a new radiator pressure cap too.
Given that you said you got some brown-ish liquid out of the radiator, you should drain/fill the system with water at least two times (3 is better) so that the final drain will be clear water. Some folks will suggest using a cooling system cleaner, but you will have to get all of that cleaner out of the system before you fill with the coolant mix. Just takes a few repeats to do that so not a big task, just some time.
You should remove the knock sensor from the passenger side of the block to make sure all of the old coolant is removed. If the car has the RPO KC4 "oil cooler", you can remove the hose that goes from the cooler above the oil filter to the hose bib on the driver's side of the block. Let water flow thru these two openings for a couple minutes and then replace the sensor and fitting.
Given that you said you got some brown-ish liquid out of the radiator, you should drain/fill the system with water at least two times (3 is better) so that the final drain will be clear water. Some folks will suggest using a cooling system cleaner, but you will have to get all of that cleaner out of the system before you fill with the coolant mix. Just takes a few repeats to do that so not a big task, just some time.
You should remove the knock sensor from the passenger side of the block to make sure all of the old coolant is removed. If the car has the RPO KC4 "oil cooler", you can remove the hose that goes from the cooler above the oil filter to the hose bib on the driver's side of the block. Let water flow thru these two openings for a couple minutes and then replace the sensor and fitting.
Thread Starter
Drifting
Joined: Mar 2017
Posts: 1,897
Likes: 165
From: Nashville TN
2017 C4 of Year Finalist
You didn't mention the condition of the radiator hoses, but when you do the flush, I would recommend that you replace both of those hoses. Can't hurt to get a new radiator pressure cap too.
Given that you said you got some brown-ish liquid out of the radiator, you should drain/fill the system with water at least two times (3 is better) so that the final drain will be clear water. Some folks will suggest using a cooling system cleaner, but you will have to get all of that cleaner out of the system before you fill with the coolant mix. Just takes a few repeats to do that so not a big task, just some time.
You should remove the knock sensor from the passenger side of the block to make sure all of the old coolant is removed. If the car has the RPO KC4 "oil cooler", you can remove the hose that goes from the cooler above the oil filter to the hose bib on the driver's side of the block. Let water flow thru these two openings for a couple minutes and then replace the sensor and fitting.
Given that you said you got some brown-ish liquid out of the radiator, you should drain/fill the system with water at least two times (3 is better) so that the final drain will be clear water. Some folks will suggest using a cooling system cleaner, but you will have to get all of that cleaner out of the system before you fill with the coolant mix. Just takes a few repeats to do that so not a big task, just some time.
You should remove the knock sensor from the passenger side of the block to make sure all of the old coolant is removed. If the car has the RPO KC4 "oil cooler", you can remove the hose that goes from the cooler above the oil filter to the hose bib on the driver's side of the block. Let water flow thru these two openings for a couple minutes and then replace the sensor and fitting.
I'll post a pic of what I think is the knock sensor in a little bit to confirm it, it looks pretty darned easy to get at though. I was getting a knock sensor code, do I need to replace that sensor while I'm at this job?
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Racer
Joined: Dec 2006
Posts: 325
Likes: 2
From: Chattanooga TN
Juse don't use Dexcool, or equivalent, unless you enjoy watching every coolant gasket on your engine seep.
Dexcool is best left to 96-up engines with gaskets designed for use with it.
BTW, most "green" coolant available today is hybrid of new and old style coolants. They don't have as bad of a propensity for leaking as Dexcool does in older engines though.
True old style green coolant that uses the old traditional silicate/phosphate additive package is actually getting harder to find these days.
Dexcool is best left to 96-up engines with gaskets designed for use with it.
BTW, most "green" coolant available today is hybrid of new and old style coolants. They don't have as bad of a propensity for leaking as Dexcool does in older engines though.
True old style green coolant that uses the old traditional silicate/phosphate additive package is actually getting harder to find these days.
Last edited by BigLee; Mar 15, 2017 at 02:07 PM.
Safety Car
Joined: Sep 2004
Posts: 3,953
Likes: 550
From: Mission Viejo CA
Don't forget to flush the heater core, too. In the '85 manual control, there should be sufficient residual vacuum in the heat/ac control system without starting the engine, to open the heater control valve by moving the temp control lever away from the full left (cool) position. Look at the heater control solenoid to confirm that it opens.
