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MG MGF Technical - Burning Question

I have noticed that my 98 mpi has been consuming oil.
I drive 400 miles each week, 80 percent motorway and have to top the oil up on a weekly basis.
It drops from the top of the dip stick down to just below the middle.
I have checked for leaks, and the engine appears bone dry and there is absolutely no evidence of it dropping oil.
Is this normal, for a four year old MGF with 55,000 miles on the clock?
6 months ago it suffered HGF and a new headgasget was fitted under warranty.
I wonder if the bottom end of the engine got too hot and is causing it to use oil?

Many thanks...
Phil

Phil, you are checking the oil when cold arn't you?
Will Munns

>>6 months ago it suffered HGF and a new headgasget was fitted under warranty.
I wonder if the bottom end of the engine got too hot and is causing it to use oil?<<

I wouldn't think it's the bottom end.
Was the head gasket job just a gasket change or did they need to skim the head ? If the latter then they probably dismantled the head and it didn't go back exactly as before (that's not saying the garage did it wrong however).

What oil are you using ?
If you're on something like Mobil 1, you may want to switch to a semi synthetic 10W40 like Esso Ultra.

Hopefully, the oil consumption will ease as you put the miles on.

Steve
Steve

Hmmm, if there is no leak then the engine is using the oil and expelling it out the rear, this will cause damage to the catalyst over time.

Have someone follow you looking for smoke from the exhausts.

If you have a continuous stream, likely to be oil getting into the combustion chamber past the piston rings. May just be worn rings, but could also be piston slap (over time, liners wear to an oval shape due to action of the piston on the crank - this allows oil to seep past the rings). Providing the oil is kept topped up the engine will go on forever like this.

If it is a puff of smoke when changing gear, this would suggest the oil is getting in past the valve stem oil seals. This is potentially more serious as there is the risk of the valve(s) getting hot and causing damage (this is the most probable theory on Scarlet's first engine's demise - valve head sheared, bounced around combustion chamber until cylinder and liner disintegrated, shrapnel inducted into head and exhaust causing final backfire which reinducted the bits into the other cylinders. Very difficult to prove as there is too much damage, who's to say what caused what? Only know that the engine was using oil and the symptom was puffs of blue smoke when changing gear).

HTH

SF
Scarlet Fever

Phil, you could try revving the engine to 4k rpm, release the accelerator.. then press it again repeatedly. if blue/white smoke is visible, then have the engine checked.

also if you can see traces of black spots on your tailpipe, thats oil being burnt. but for a more accurate check, have a look at all your spark plugs. compare them with each other. none should be black/oily.

good luck.

Jason

I have taken your advise and have decided to examine the spark plugs...
removed the engine cover...
removed lead...
using socket and extension bar loosened the plug...
but cant get the plug out of the deep recess where it "lives" ... life is sent to try us.
I agree that the plugs must be examined, will have to buy a magnetic plug wand / remover, unless I can bodge it somehow?

Thank you for your replies.
Phil

I use a length of flexible tubing and push it over the end of the plug to remove it from the recess. The tubing is actually from an old wine making kit. I'll try anything not to have to communicate with the morons at Halfords.
Neil Stothert

Another "problem" that has shown up in the past is the dip-stick tube cracking and leaking.

Might be worth taking a look at that.

If you're burning oil that fast, I've got a feeling you'd be producing visible smoke from the exhaust...

Neil.
Neil

Neil, what diameter of tubing do you need for removing the plug. I agree that Halfords are a bit of a joke and your solution sounds good.


What kind of oil consumption is the norm for the F, top it up once a month?

If what I am saying about oil consumption is correct, do you believe I have grounds to contact the warranty Co. and investigate further claims?


Many thanks for the replies

Phil
Phil

Phil, If you can stand halfords then a socket which is designed totake plugs out will have a rubber insert which grips the plugs to help you pull them out, only trouble is when you put them back in the socket gets stuck!

Alternativly wind plug all the way out, then back in half a turn to keep it central, then use the leads to plug on, twist out and then retreive.

Will
Will Munns


Will, thanks for the suggestion, I will try this before more spending money at Halfords.

I have noticed that there is a black deposit build up on the exhaust surround...

is this indicative of burning oil ?

The impression the warranty company give, is that there is a problem with the engine.
Please tell me not all MGs are as reliable as mine, since I wouldnt mind getting a TF.

Does MG stand for More Garages?

Thanks for the replies.

Phil

Phil

I use one of those magnetic screwdrivers with the interchangeable bits. The top of the plug fits neatly into the bit holder on the end of the screw driver - works perfectly.

Gaz
Gaz R

> I have noticed that there is a black deposit build up on the exhaust surround...

>is this indicative of burning oil ?

I would have thought not, unless there's lots of it and its oily in consistancy.

Unleaded fuel leaves a black deposit on the exhaust (unlike leaded which leaves a light grey/brown).

Have a look at the back of another F for comparison with what is "normal" levels/type of black deposit (or indeed almost any other modern car!)

I'd go for a run and then stick a bit of cardboard/newspaper (depending on how windy it is!) under the engine and see if any drips form overnight...

Neil.
Neil

Thanks for all your posts and solutions to the problem.

Nothing wrong with it in the end... except my inability to dip the oil and obsession with assuming the worst with my F.

Pulled out the stick, wiped it, replaced it and it looked half empty on one side... if I had looked on the other side it would have read nearly full. My fault but still a bit confusing.

Many thanks

Phil
Phil

A cheap and effective plug tool is to use a length of heater hose. It is simply pushed over the end of the plug and has a good grip to wind out the plug for removal. It is also ideal fro refitting since it again has enough grip to allow the plug to be wound in, but very importantly if you strart to cross thread then the hose will slip on the plug and stop before any damage is done. It is always prudent to hand fit spark plugs, especially in alloy heads as it is far to easy to continue winding a crossed thread and damage is done before you realise it.

Rog
Roger Parker

So If you kept topping it up when it was full, where did the oil go? I assume it just burnt it off but it cant be too godd for it
Paul

This thread was discussed between 28/08/2002 and 08/09/2002

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