check your antifreeze

[JimR]

About antifreeze, why do people change antifreeze so often when it really doesn't need to be changed. I worked as a mechanic for over 10 years and still wrench a lot of things when needed. I can't ever recall changing good antifreeze for no good reason. My wife had a 1999 Acura 3.2 TL aluminum block motor. We bought the car in 2002 with 49K on it. We sold this car this year with about 218K miles on it. I think I added antifreeze around 120K when I replaced the timing belt and water pump. I never flushed out the system or replaced all of it. The same goes for two Chevy Blazers that I owned and sold with around 175K on them years prior and many other vehicles that we have owned over the years. Trust me, I already know what the experts say and how often that you need to change it out. Just like telling you that you need to change your engine oil in your daily driver every 3000 miles.

 

[xcgreene]

About antifreeze, why do people change antifreeze so often when it really doesn't need to be changed. I worked as a mechanic for over 10 years and still wrench a lot of things when needed. I can't ever recall changing good antifreeze for no good reason. My wife had a 1999 Acura 3.2 TL aluminum block motor. We bought the car in 2002 with 49K on it. We sold this car this year with about 218K miles on it. I think I added antifreeze around 120K when I replaced the timing belt and water pump. I never flushed out the system or replaced all of it. The same goes for two Chevy Blazers that I owned and sold with around 175K on them years prior and many other vehicles that we have owned over the years. Trust me, I already know what the experts say and how often that you need to change it out. Just like telling you that you need to change your engine oil in your daily driver every 3000 miles.

If folks tested their coolant, I think we'd see a lot less coolant changes. But as contaminants ingress over many years, for any number of reasons, problems arise. If the color is good, alkalinity and PH are correct, and glycol amount is sufficient for my area, I will not change.

 

[ritcheyvs]

About antifreeze, why do people change antifreeze so often when it really doesn't need to be changed. I worked as a mechanic for over 10 years and still wrench a lot of things when needed. I can't ever recall changing good antifreeze for no good reason. My wife had a 1999 Acura 3.2 TL aluminum block motor. We bought the car in 2002 with 49K on it. We sold this car this year with about 218K miles on it. I think I added antifreeze around 120K when I replaced the timing belt and water pump. I never flushed out the system or replaced all of it. The same goes for two Chevy Blazers that I owned and sold with around 175K on them years prior and many other vehicles that we have owned over the years. Trust me, I already know what the experts say and how often that you need to change it out. Just like telling you that you need to change your engine oil in your daily driver every 3000 miles.

Almost all antifreeze is ethylene glycol plus additives. A less toxic alternative is polypropylene glycol plus additives. The actual glycol doesn't wear out but the additives do and that's the reason it needs to be changed every few years. Additives lubricate for the water pump and prevent corrosion. Old antifreeze won't freeze but it may damage the water pump and will not prevent corrosion.

 

[ruffdog]

Almost all antifreeze is ethylene glycol plus additives. A less toxic alternative is polypropylene glycol plus additives. The actual glycol doesn't wear out but the additives do and that's the reason it needs to be changed every few years. Additives lubricate for the water pump and prevent corrosion. Old antifreeze won't freeze but it may damage the water pump and will not prevent corrosion.

I have read that a glycol antifreeze is good for about 12 years or more. Also, do not mix the two (PG and EG) glycol coolants.
http://www.veoliawatertech.com/crownsolutions/ressources/documents/2/21823,Glycol.pdf

 

[ruffdog]

You also need different testers for EG and PG coolants.

 

[jrskblx125]

there are differences between freeze point and burst point. example: an outdoor chiller unit with an open tank, we can run at 30% propylene glycol no problem in massachusetts and we see temps down to -10 in winter. i mean technically, the glycol will slush up as it reaches its freeze point, but will not expand much until it gets much colder.

ethylene glycol, at 40-75% concentration, has a BURST point of -60 F. the FREEZE point is -13F at 40%. a good target is always 50% because its easy to achieve in such a small volume.

seeing as your engine cooling system is open to atmosphere and not under pressure while cold, you could theoretically run 30% and you would have burst protection down to -14F.

 

[jrskblx125]

should follow up that the water pump isnt designed to move slush though haha. but you dont need to worry about cracking a block.

 

[gb6049]

Got to put a new fan belt and radiator hoses on my '67 in the next few days and plan to replace the coolant since I have no idea when the last time it was changed since I bought it last year.

 

[DieselBound]

I'd heard someone mention checking pH. I suspect that the primary additives are for guarding against corrosion, in which case pH would be a good way to test against: take new antifreeze and check pH and then use that as the reference. How much degradation is OK is the real question. I'd been meaning to test this but haven't gotten around to it.

 

[jrskblx125]

I'd heard someone mention checking pH. I suspect that the primary additives are for guarding against corrosion, in which case pH would be a good way to test against: take new antifreeze and check pH and then use that as the reference. How much degradation is OK is the real question. I'd been meaning to test this but haven't gotten around to it.

I do water treatment for a living and test plenty of glycol loops. Inhibited glycol mixed to 30-35% generally will run from 8.3-9.0. Increase it to 50% its usually just around 9.0.

In industry, ive seen 20 year unchanged propylene glycol. Ethylene should last longer. It really depends on the heat load though. This place was cooling vacuum furnaces so the temps were like that of a motor.

In my opinion something like ethylene glycol would be on a 10 year changeout cycle in a motor. And even then probably wouldnt need it but its easy enough.