Flushing Coolant
Thread Starter
Melting Slicks
Joined: Apr 2003
Posts: 2,150
Likes: 6
From: NS
Flushing Coolant
I'm going to replace the coolant in my car this spring before I drive it. Any tips to help me out?
I've got about an inch of sludge in the filler tank from the "sealant pellets" GM uses. My service manual says I should put new pellets back in, but I vaguely remember a service bulletin changing that. Does anyone know for sure if GM still recommends the sealant pellets in an LT1?
Thanks
I've got about an inch of sludge in the filler tank from the "sealant pellets" GM uses. My service manual says I should put new pellets back in, but I vaguely remember a service bulletin changing that. Does anyone know for sure if GM still recommends the sealant pellets in an LT1?
Thanks
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
The bulletin that GM sent out advised to no longer use the pellets in any system that originally had them.
If you have a lot of visible gunk in the system, you might try a cooling system cleaner made for aluminum radiators. A lot of the stuff out there can hurt more than help. A competent radiator shop can flush the stuff out for you as one big issue is the disposal of the old coolant and the junk that's in there. Not something to go down the storm drain....
You might consider new upper and lower radiator hoses if they feel soft anywhere or it they show signs of cracking. This would be a good time to have the cap checked (or replace it as they are not terribly expensive) for its ability to hold pressure, remove the overflow tank and clean it out before refilling with new coolant.
If you have a lot of visible gunk in the system, you might try a cooling system cleaner made for aluminum radiators. A lot of the stuff out there can hurt more than help. A competent radiator shop can flush the stuff out for you as one big issue is the disposal of the old coolant and the junk that's in there. Not something to go down the storm drain....
You might consider new upper and lower radiator hoses if they feel soft anywhere or it they show signs of cracking. This would be a good time to have the cap checked (or replace it as they are not terribly expensive) for its ability to hold pressure, remove the overflow tank and clean it out before refilling with new coolant.
