PSA: Mk4 Coolant Balls

[BaggedGLI]

Everyone who has a MK4 with the round coolant ball, please go disconnect your coolant level sensor and check for coolant in the plug.

There is a known problem of the coolant balls leaking. When they start to leak inside the connector it has a seal and the heat cycles can force coolant through the insulation on the wires. We have seen cars at the shop that have had coolant pushed into the instrument cluster and all the way back to the fuel pump. Obviously this can cause big problems in the electrical system.

So pull the level sensor, take out the little orange seal. If there is coolant in there, get a new coolant ball ASAP and leave it disconnected.

[All_Euro]

Re: PSA: Mk4 Coolant Balls

Thanks for the heads up

[Geobmx4life]

Re: PSA: Mk4 Coolant Balls

Great info, will do...thanks Colin!!!

[Benjamin]

Re: PSA: Mk4 Coolant Balls

Coolant migration, been a tdi issue for over a decade. Was really bad in early mk4's, problem seems to have fallen off the radar though. Tdi's pile on the miles way quicker and run into these problems quicker then gas I have found.

[Benjamin]

Re: PSA: Mk4 Coolant Balls

http://forums.tdiclub.com/showthread.php?t=88208&page=1

Easy fix, drill a small hole past the seal and problem is no more. Saves buying a new coolant bottle, and dealing with replacing it.

[witchcraftz]

Re: PSA: Mk4 Coolant Balls

I've always wondered if you couldn't just swap in a mk5 or mk6 coolant ball?

[Benjamin]

Re: PSA: Mk4 Coolant Balls

I replaced mine while chasing what turned out to be a head gasket issue. The new bubbles fix this issue for the mk4's, the drill option is way quicker and cheaper though.