Flushing out previous "Stopleak" ?

[GoStumpy]

1998 Acura RL, I bought the car with a cracked radiator, and it was apparent that the previous owner tried to use stopleak to fix it, and I'm willing to bet she used more than one bottle... The fluid seems to have coagulated chunksin it at and near the radiator cap..

I replaced the radiator and filled it with new coolant (will post what brand when I get home) and purged the air from the system..

I'm thinking it would probably be wise to flush all the old [censored] out, anyone have some tips on how to flush out the old [censored]?

I don't mind buying a couple gallons of coolant to know that it's clean stuff I have in there instead of half the old gunk and half new.

Also, when I open the hood after driving to work and the engine has cooled, the top rad hose is sucked almost tight, like it has a serious vacuum inside the hose. Is that a bad radiator cap?

Thanks for any help!

 

[Drew99GT]

Remove the thermostat and jam a garden hose where the thermostat goes and reverse flush the engine block; do the same with the radiator.

Yes, bad cap in my experience when the hoses collapse; it's probably all gummed up with stop leak and preventing the seal from releasing and the vacuum from the engine cooling collapses the hoses instead of drawing coolant from the overflow tank.

 

[GoStumpy]

Thermostat in the '98 Acura RL is at the very bottom of the radiator.. climb under there and put a hose where the thermostat was?

-edit-

Oops, perhaps I'm thinking temp sensor, not thermostat

 

[eljefino]

I'd run a few changes of water (when it warms up) then finish with full strength antifreeze, to make 50/50. And a new cap is a given.

If you want to flush like a wierdo, unhook the the (cold) top hose from the radiator, hold it up high, and pour the water in that into the engine. It'll gurgle its way through the system and eventually out the top radiator nipple. Followup with a drain from below to get the crust that's loose in the lower parts.

 

[GoStumpy]

And I suppose the best way to drain is to just remove the bottom rad hose?

 

[user52165]

If your block has a coolant drain bolt (maybe 2) remove those also for best results.

 

[HTSS_TR]

Buy a heater hose and T-flush, install T-flush to the heater hose and replace it to the current hose, use garden hose to flush all coolant fluid, replace the T-flush with current hose.

 

[GoStumpy]

My mechanic friend gave me a T fitting for the heater hose... but there are no visible heater hoses except the ones behind the motor against the firewall... no way I'm getting anything down back there, too cramped. That is what made us give up on flushing it at first.