Mayo in Oil Filler Tube

paul001 · Post by **paul001** » Wed Mar 18, 2009 8:35 pm

While refitting the split hose I noticed it will lined with a nice yellow/toffee colour mayo like substance I am aware that this is a common sign that the head gasket is dead or dieing and I would like to know before I start the big job of replacing it, not looking forward to the exhaust pipe bolts, is this a common issue with BX's? I am considering taking it to college over next week and dip testing with the magic blue chemical but would like your guidance and knowledge first as I really don't have time to replace the head gasket right now.

Philip Chidlow · Post by **Philip Chidlow** » Wed Mar 18, 2009 8:41 pm

This happens to an extent with all petrol BXs (don't know if it happens with diesels). The mayo is down to condensation. Clean it out regularly and make sure the upper pipes aren't blocked. Short runs and cold weather will make it worse.

To be sure, take the rad cap off. If the mayo's there too, well it is not such an innocent problem...

paul001 · Post by **paul001** » Wed Mar 18, 2009 8:50 pm

No mayo in the rad cap. Thought i'd get the low down from you guys first

Way2go · Post by **Way2go** » Thu Mar 19, 2009 1:23 am

Philip Chidlow wrote:This happens to an extent with all petrol BXs (don't know if it happens with diesels). The mayo is down to condensation. Clean it out regularly and make sure the upper pipes aren't blocked. Short runs and cold weather will make it worse.

Yep, this is normal and even happened when they were new.

Mike E (uk) · Post by **Mike E (uk)** » Thu Mar 19, 2009 11:06 pm

All my BXs (all petrol) have done/do this. I have never had a head gasket problem on any car I have owned.

Each oil change, I take off the emission control hoses and the oil filler cap, and wash them through with the garden hose.

I replaced the rusty gause in the cap with one of those stainless steel kettle anti scale devices. Much better, does not corrode and is easier to clean.

Using a semi synthetic oil seems to help, but the mayo always reappears in the end.

I don't worry about it any more. It is normal.

Mike

ellevie · Post by **ellevie** » Fri Mar 20, 2009 7:10 pm

Same for me and my 19TRS. This was reported to me on my first service back in 1994 and she still pulls like a train after all the years since.

kiwi · Post by **kiwi** » Sat Mar 21, 2009 12:40 am

Its Normal to have Mayo in your filler cap.

Headgasket Failure on the BX is never a simply diagnostic. Should know had one fixed that took a year before finally giving out and none of the so called symptoms were present or consistant.

Basically if you drink a lot of Water thats a good sign of Head Gasket Failure. Didnt have the Oil in Water and vica versa symptom.

What I did have was a cyclinder full of water after leaving the Car Standing for 3 weeks.

But Mayo is not a relaible sign as the BX is famous for it.