Mayo in expansion tank but not under oil cap. Halp me

[zeta]

As title, my wife's clio '53 plate 1.6 16v (dynamique?) has the dreaded mayo of doom in the coolant expansion tank. It's stuck around the top of the tank only. Immediately looked under the oil cap to confirm knackered head gasket but its fine under there. Not a single drop of mayo. What could cause this?

Im thinking of just getting a new expansion tank and empty the system, flush and refill with cat D yo

 

[zeta]

Anyone?

 

[Thrill]

Mayo is normal round the filler neck. Do you do a lot of short or stop start journeys? Could be why.

 

[mad pierre]

It it running the correct coolant,

 

[zeta]

Car is used daily to get to work about 35 mile round trip. No idea what coolant is in there at the moment. Hasn't been changed since we got the car about a year ago. Best bet is to flush it and replace I think

 

[Thrill]

Yeah probably someone's mixed the coolants up. Get the renault type d stuff in there, only about £12 for a 5 litre bottle!

 

[zeta]

Sounds about right, looking through the service history it doesn't look like its ever had a full coolant change. I'll get down the dealership in the morrow y0!

 

[Thrill]

At first u thought this was mayo in oil filler cap. Realised it's coolant haha. I think that'll sort it mate

 

[zeta]

Quick Update. I've been down the dealers and picked up a case of coolant. Thought I'd fix the small leak in my radiator at the same time. The wife's is all done and dusted now. Ordered a new expansion tank to fit later but all good for now

 

[Darius]

How do you change the coolant ?

 

[zeta]

Similar process on both cars just had to take the front off mine for better access.

Remove lower hose to radiator and catch coolant in a bowl. I found using a pair of needle nose molegrips easier than regular ones.
When no more comes out, removed bleed screw on n/s of thermostat housing and catch remaining coolant that flows out.
Replace bleed screw and flush system with hose from expansion bottle til water runs clear out of bottom hose.
Remove top hose and repeat flush until clear.
Connect all hoses back up and remove bleed nipple again.
Slowly pour Type D coolant into expansion bottle until it runs in a constant stream out of the bleed nipple.
Replace bleed nipple.
Top up coolant to max level on tank.
Fire up the car and run at fast idle for about 20 mins or take a drive around the block.
Once thermostat opens and fan kicks in, keep an eye on the expansion tank and top up as necessary.

That's pretty much it. Quite an easy thing to do with basic tools and a little bit of time

 

[zeta]

It it running the correct coolant,

Forgot to mention, it was full of water. No visible coolant what so ever!

Good job it's been sorted now

 

[Thrill]

Forgot to mention, it was full of water. No visible coolant what so ever!

Good job it's been sorted now

Crazy! Least everything's sorted mate.