Onset of mayonnaise !!! **Resolved**

[Bela]

Yes as the title states, I refilled the water in my car last week as the temperature gauge kept on bouncing up and down, and the heater was blowing hot intermittently.

It took two litres of water to top up a week ago so thought I'd check it again today, took another litre to fill up.

So went ahead and checked what was on the oil filler cap, and there was a small trace of water and mayonnaise.

Engines an M52 B28, any one had this problem? What did you do to resolve it?

Tia

[FinalD]

I had that on an E36 328i...I ended up scrapping the car as the engine blew up...


To make you feel better...Have you been doing short trips (few miles only) at a time or doing decent length trips (20miles or whatever)? If it is the former then the mayo could just be due to condensation if you're lucky.

Check the whole coolant system for leaks, it may just be dropping coolant from a hose and the mayo could be condensation as above. Also make sure that the radiator cap isn't leaking and creates a proper seal, I had an issue with a 4pot e36 causing it to not pressurise and leak coolant.

Don't just 'top up' the coolant on a 6 cylinder BMW, make sure that you fully bleed it and also don't just use water, use proper coolant. The M52 is prone to taking badly to an incorrectly bled system (nose properly in the air, heaters on full etc.).

Also check things like the thermostat and the viscous fan unit.

You could just be lucky and having not done your bleed properly it'll still have air in the system but unfortunately it doesn't sound like that is the case.

[zaust]

And check the cyclone valve is not blocked, this will give you a yellow tint to the mayo.

[Bela]

And check the cyclone valve is not blocked, this will give you a yellow tint to the mayo.

Not sure what the cyclone valve looks like tbh, but thanks for all the comments.

Anyway an update is long overdue.....

I can happily report I have sorted the intermittent heating issue out now (not that it overheated to boil over point ever).

i used a product called blue devil and white sheppard (stops oil leaks), worked a treat. However to use this product your car must be able to idle without overheating for at least an hour.

I took my radiator out and gave it a good flush (there was a lot of gunk in there), reinstalled it and followed the instructions on the blue devil bottle (bar taking the thermostat out as I didn't have the right tools). Once cooled down I flushed the system out, and refilled with coolant.

I am not guaranteeing this will work for everyone, but worth a try at about £40-50 a pop.

To confirm the liquid did its job, I have done a 100 mile round trip in traffic and free flowing routes (on a hot sunny day) and had no overheating issues whatsoever.

This is a weekend car so doesn't get to see more than 10 miles in a single trip.