Is this normal?

[eth]

Hi, I have had a lot of mayo build up in the rocker cover over the last few months . I'm at a loss as to what is causing it or is this just normal (for a moggie)? Not being a seasoned owner and all.

My initial thought was the head gasket. Ruled this out for now because the water and oil stays clean, it compression tests ok and it doesn't overheat.

This lead me to think its not running hot enough. I replaced the stat which turned out to be an 82deg with an 88 and fitted a new rad cap. My round heater now kicks ass but I'm still getting mayo

Any words of advice, wisdom or encouragement are welcomed.

[kennatt]

caused usually by cold air flow over the rocker cover.combined with short runs,usually goes if you give it a long fast run to get the temp up long enough to dry out the moisture,just make sure the breather pipe is clear,it probably will go once the weather warms up. If ever it does I once read and saw in an old car mag where someone had made up an air deflector(MGB I think) and fitted it to the front rocker cover bolt, claimed that it eliminated the problem by preventing the cold airflow over the cover,thought it was a good idea ,but never tried it myself so don't know if it worked.

[bmcecosse]

As above - make sure the breather system is completely clear. Remove the cover and clean it thoroughly - and probably a good idea to do an oil and filter change. It will clear with good summer runs!

[eth]

Well thats encouraging! I dont really do short journeys (15miles each way to work) even a couple of hours on the motorway here and there made little diffenence. As a rule i clean out the breather every few days and the cover every week or so.

I might try making a tea cosy for it

What temperature do you think these engines run at? I am calibrating a C-N-H temperature gauge. Father thinks boiling water should be on the cold side, i disagree as my rad has never come anywhere near boiling and never really pressurises, i fear 100deg would boil it over.

[lambrettalad]

moggies are very very over cooled my thermostat opens at 92? this has made me think it might be 88 i'll check yes it's 92C

[dalebrignall]

mine is doing the same thing i went to brooklands on sunday which is 40 odd miles temp only got to 60 degrees and that was doing 60 mph .i tend to find it goes once it warms up .

[eth]

mine is doing the same thing i went to brooklands on sunday which is 40 odd miles temp only got to 60 degrees and that was doing 60 mph .i tend to find it goes once it warms up .

60 degrees seems very low to me considering my heater blows air at about 40deg! This makes me think I have got head problems if your engine manages to clear mayo at such low temps and mine can't even after 2 hours of non stop motorway driving . Is your thermostat even working?

I will definitely be making a tea cosy for the rocker cover before I ponder any more over the head.

[bmcecosse]

When was the oil last changed? It may be loaded with moisture. But the main thing is to draw moisture away with the breather system - one connected to the inlet system (either to the air cleaner or - much better - directly to the carb) and also make sure the other breather pipe from the cam follower chest is open to atmosphere. And of course - is the engine using any water ??

[eth]

The oil was changed 2500 miles ago, it was still messy after the last oil and filter change which included engine flush. The top breather goes to the filter housing the cam chest breather hangs down in the wind both of which are clear. I cant be sure if the engine uses water as the rad has a few small leaks as does the heater tap. I will be getting a new rad next month if finances allow.

[moggiethouable]

I plonked this in the spot where the rad cap goes once the thermostat was opened[frame][/frame]

[JOWETTJAVELIN]

This mayo was something I worried about but it is only, as people have said, condensation.

Let us consider why.

The Minor has a large open engine bay allowing lots of air to circulate; the engine also happens to have a larger-than-necessary radiator.

Add to this the fact that the rocker cover is insulated by cork and is right at the top of the engine, where there is no hot water circulating or indeed much hot oil, and it is plain to see why problems arise.

A good run will burn things off, or even a 30 grade oil would lessen the problem in winter.

[bmcecosse]

Change the oil and filter again - don't waste money on 'engine flush' ! Wilco 20W50 is back again - at £9 now....but it's fine for a Minor.

[DAVIDMCCULLOUGH]

If its a really bad build up its unlikely to clear even on a long run. I usually take my rocker cover off at oil change time and clean the mayo off with some newspaper and refit while the oil is draining out.

[eth]

I would definitely class it as bad build up. I drive 15 miles each way to work and have to clean it out every two weeks or less not every oil change! I wouldn't be concerned if that was the case.

I changed the oil last time due to the onset of this problem and it made no difference ... at all. I will certainly be changing the oil in the next week or so as a matter of course.

The more I ponder on this the more I think I have a cracked head or worse block. It wouldn't surprise me considering the car had no anti freeze when I bought her back in september but I failed to realise for a month or two (November ish)

[kennatt]

forget the cracked head,it is condensation. Take the blades off the fan that could clear the problem,put them back on if the temp goes up in the summer,the minor is very much overcooled and will run fine without overheating just watch leaving it ticking over for a long time where it may overheat without the blades when just sitting there without air flow through the rad.,This condensation problem doesn't exist in moderns because they dont have a fan that turns all the time,they have electric fans that very rarely come on at all,so no cold air over the top of the engine. If you had a cracked head or blown head gasket you would know about it,like you would be filling up with water every day and it wouldn't be running very well with a head gasket gone. also the oil on the dip stick would show water in the sump if you had a cracked head or block cos thats where it ends up not on the rocker cover,the oil on the dip stick is just black oil ,is it Just forget about it as long as the breather pipes are clear all will be well.

[eth]

Yep just black oil on the dip stick, I'm going to go back to not caring now. I dropped a thermometer in the top of the rad this morning and got 85C, I will fit a 92C stat and see how that goes . Also purchased some spares to fix most of my water leaks hopefully that will prove where my water has been going.

[bmcecosse]

Summer is coming - that 85C is fine, don't go any higher at the moment.

[eth]

You all may have thought I was joking when I said I was going to make a tea cosy for the rocker cover ... well ive done it, more like a beanie hat. I couldn't manage to upload a photo from my phone

[kennatt]

if it works,and it just may,you will need to patent it cos everyone will want the moggie tea cosy

[eth]

[frame][/frame]

Taking orders now, patent pending.

It really does a good job keeping the cover nice and toasty, its now too hot to hold your hand on where as before it was just warm. I have high expectations!