Radiators and Coolant System RUST!!!

Info: 2000 XJ 4.0

Problem: RUST! EVERYWHERE IN THE FLIPPIN COOLANT SYSTEM!!! THREE TIMES!
Me and a friend have tried to kill the rust in hisXJ for a while now and it just WONT get out of the block! It has costed him a new water pump, 2 new radiators, a heater core, and now again the filler neck of his new radiator (less than 8 months old) has been eaten through. Now I know the rust couldn't have chewed up the aluminum radiator or copper heater core... and we thought we've flushed it out of his system but now we cant figure out why its back, OVER AND OVER AGAIN!
My brother, a master mechanic, told me it had to do with the wrong anti-freeze mix (more water than antifreeze and cheap anti-freeze) and electrolytes eating the steel block up and all that electricity eating away at the internals of the aluminum or copper. Does that sound right? We're gonna do one last flush with the new radiator that's coming in next week and I'm gonna flush and burp the block too using compressed air to flush it out.
What shall we do scooby doo?! He's so tired of it coming back that he wants to get a new motor and that's gonna cost him about a grand with a back yard install and all new coolant system parts.

i probably have the worst mix of antifreeze in my xj and the fluid is clean. also what might be happening is he rust is stuck in the heater core. try flushing that to. but i dont know if that still apples you year.

Though not ideal, a thin layer of rust won't effect the cooling performance if everything is in good shape. Keep it on a good maint. schedule and all's well.

we're gonna flush it all out with a radiator flush chemical and an electrolyte remover. and then do a new radiator and go from there....

you doing the flush where you hook the hose to it?

also, make sure you drain the block. I believe there's some kind of drain plug for the water jackets on the block, right? anyone?

ya i think you right but i can never get them to open. though i have stopped trying.

JNickel101 said:

you doing the flush where you hook the hose to it?

also, make sure you drain the block. I believe there's some kind of drain plug for the water jackets on the block, right? anyone?

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There is, it's suppose to be on the back drivers side of the block behind the manifold, BUT if you remove the t-stat then you wont have to do that, right? Makes sense... this way, all i do is remove the t-stat and bolt it back up for the flush, flush and chem clean and water flush and burp, then drain and install new t-stat and install proper coolant mix. Right? anyone?

I agree it could have been caused by cheap antifreeze or if somebody mixed it themselves mabey they didnt use distilled water.
Something like that happened to an old dirtbike I bought, the aluminum crankcase cover was all pitted and eaten away near the water pump, it had even gotten so bad there was a good size hole between the water pump and transmission so all of the antifreeze drained in and mixed with the gear oil. Unfortuanly I didn't realize this till after I bought it.
Sorry if this was a little off topic but my point was, the corrosion most definatly could be caused by electrolytes in the antifreeze or the use of undistiled water.

selarep said:

There is, it's suppose to be on the back drivers side of the block behind the manifold, BUT if you remove the t-stat then you wont have to do that, right? Makes sense... this way, all i do is remove the t-stat and bolt it back up for the flush, flush and chem clean and water flush and burp, then drain and install new t-stat and install proper coolant mix. Right? anyone?

Click to expand...

It is impossible to get all the old fluid out of the block without pulling the drain plug. If you flush enough, most of the gunk will come out though. Just removing the thermostat will only allow the fluid that is at the level of that and up to come out. Gravity works on water too.

Jess said:

It is impossible to get all the old fluid out of the block without pulling the drain plug. If you flush enough, most of the gunk will come out though. Just removing the thermostat will only allow the fluid that is at the level of that and up to come out. Gravity works on water too.

Click to expand...

OOOOoooo Yeah. Forgot about that part... it's a pain to get to but then again so is the damn plastic drain valve behind the lights on the 97+.

dont forget to pre-order your Tefba coolant filter from me too.