Beginning of the end for my M40

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jmc330i
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Post Tue Jan 01, 2013 2:46 pm

Starting the car in the early hours of this morning, I realised the oil pressure light was flickering for a couple seconds after start up. It's not done this before (usually goes straight out), so could this mean its struggling to get the oil pressure up?
It's flickered after every start up now, hot or cold, but stops flickering and goes out after 3 or 4 seconds.

The engine had/has a possible headgasket issue as there is always a build up of mayo, although it uses no water. It's been flushed through etc and has clean oil, but I'm guessing the mayo has done its worst and the damage is done :(
James
'91 325i Sport
'93 318i touring 16v
Grrrmachine
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Post Tue Jan 01, 2013 3:28 pm

Sure it's not something silly like the sensor getting gummed up? Whip it out and soak it in petrol to check.
jmc330i
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Post Tue Jan 01, 2013 5:10 pm

It could well be, the amount of mayo that was in there it wouldn't surprise me at all. It explains the sudden top end ticking thanks to the gummed up oil spray bar!
Tbh, I'd rather it was the beginning of the end, that way I can swing a new engine by er indoors :lol:

Either way, I'm sure it will carry on as is for a little while.
James
'91 325i Sport
'93 318i touring 16v
Andyboy
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Post Tue Jan 01, 2013 7:21 pm

M40 oil pumps do wear out leading to just this. But if it sounds healthy when hot, forget about it.
jmc330i
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Post Tue Jan 01, 2013 7:58 pm

Thanks Andy, I did wonder if the thick mayo had cause premature wear to the pump - I have no idea how long the oil was like that before I got the car.
It is very ticky (the cam lobes are very pitted), a lot more so than when I first got it, but I'm not too worried about that. No oil light or strange noises once warm, so it will just get driven. Hopefully it will keep going until I can get the M44 I've got lined up.
James
'91 325i Sport
'93 318i touring 16v
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Billwill
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Post Wed Jan 02, 2013 11:10 am

There are known problems in the M40 with oil pump mounting bolts coming loose and also problems with the sump gasket fouling the oil pump up if not fitted correctly.

Brianmooore will have more info on these two subjects! :)
Andyboy
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Post Wed Jan 02, 2013 6:39 pm

The oil pump is built into the front timing case and runs off the nose of the crankshaft. It's the oil strainer/pick up pipe that can come loose but it's pretty rare. The M40 upper sump has a gasket that can slip and cause air to be drawn in but this seems to be more a 318iS issue - not that M40's won't be affected.
M40 sumps are easily removed so, for the price of a new gasket for the sump and the oil pick up, it's a worthwhile day's work.
soul4t
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Post Wed Jan 02, 2013 10:44 pm

@Andyboy, just to confirm, do you recommend that the Oil pick up be replaced if opening up the sump...the gasket obviously, just want to confirm which parts to get if one is going to perform the task.
Andyboy
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Post Thu Jan 03, 2013 5:23 pm

I'd replace the gaskets but first of all drain the oil, remove the lower sump and check that the front 'inner' 10mm bolts are tight.
soul4t
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Post Thu Jan 03, 2013 5:30 pm

Great, thanks!
jmc330i
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Post Thu Jan 03, 2013 5:35 pm

Cheers guys. I 'borrowed' some oil from work, so will pick up another filter and do another oil change. I'll pop the sump off whilst its empty and have a look.

I've already drilled the oil spray bar a little, and that still seems to be coating the cam quite nicely, but its still ticking away, although not surprising with the state of the cam lobes :(
James
'91 325i Sport
'93 318i touring 16v