Pellets to Radiator

[KevinW]

I have used them and never had a problem with them. If too many are used, they can plug up the heater core.

My experience with them has also been 100% positive. Apparently, they can be used safely at up to twice the recommended concentration (at least). If coolant flow through the heater core is reduced after the addition of these pellets, chances are the internal passages were already fouled by debris stemming from a long history of cooling system neglect.

[JimD]

....If coolant flow through the heater core is reduced after the addition of these pellets, chances are the internal passages were already fouled by debris stemming from a long history of cooling system neglect.

That "long history of cooling system neglect" is part of the risk used car buyers assume ever day. When something goes badly wrong, the "shift the blame" game begins.

In my Northstar experience, the smallest inside diameter pieces of plumbing in the entire cooling system are the calibrated hole in the "hollow bolt" and the fitting at the top of the coolant reservoir. Theoretically, if a restriction occurs it would occur in one or both of those two places.

[84Eldorado]

I'm purchasing an 84 Eldorado with the 4.1 V8 and driving it about 400 miles home when I pick it up.  Is it safe or necessary to add a tube of Bars Leak Seal Coolant Powder (G12BP) without first flushing/draining and refilling the coolant system.  Car has 69,000 miles and no way to confirm if pellets where ever used in this car or if this car has a history of leaks.  Car has not been driven a lot the last 4-5 years.

[OldCadTech]

You posted in a 5 year old thread but @Bruce Nunnally can move it to it's own thread...

I would not add bars leak. The pellets and the bars leak combine to make a goo that plugs radiators. Make sure the coolant is at the proper level and drive it. I guarantee the pellets are in the system still. Can't get those horse pellet things out hardly once they dissolve.  

When you get home, flush the cooling system, add new coolant and then use new pellets (crushed, don't put them in whole) or bars leak, replace the radiator cap and t-stat. Add the bars leak or the pellets (crushed) to the intake, under the t-stat before you reinstall the new t-stat.