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MG Midget and Sprite Technical - Oil leaks and Oil pressure

Hello,
Since I have started using my car regulary I have gained not one but two oil leaks,as you look at the engine from the front the leak on the right side of the block is far heavier than the one on the left and also with this my oil pressure doesn't move above about 44ibs.
Now I know I used to get about 74ibs under load and dropping to around 62-66lbs.
Could the two problems be connected especially with the greater of the two leaks.

Thanks for looking. Wayne.
W Williams

Which engine is it?
Dave O'Neill 2

Dave,

That's why we have vehicle profiles on the forum ;0) it's a 1275.
Gary & Gaps

Gary

Don't look at them...particularly on steam-driven Blackberry!
Dave O'Neill 2

Dave, profile is 1275.

Loss of pressure could be due to leaks but it would need to be a very big leak. Any chance of an exact location of the leaks or a couple of pic's?
Possible they are not connected and drop could be due to the pressure relief valve is stuck open, but that's just guessing without more info.

MGmike
M McAndrew

Cheers,
About the pressure relief valve,is it easy to strip down and clean and is there anything that might need replacing.

Thanks again
W Williams

Hi Wayne,

This months mascot magazine, (the one with your car on the front cover) look at the bottom of page 39. It's very easy to clean as it has very few parts, though I'm not sure that you can get it out without removing the Dizzy.
It may be possible with a large (1 inch?) thin walled socket. Others may be able to answer that better than me.
Gary & Gaps

There are 2 types of relief valve fitted to A Series engines and neither require the removal of the dissy to gain access. Simply undo the large nut and gain access to the spring and the valve. The valve will be either a ball or it will be like a plunger, both do a good job and any dirt will unseat either and cause issues.

However I am more curious about your oil leak. The one on the right hand side as you look at the engine is confusing can you see where it originates.
Bob Turbo Midget England

Removal is the easy part. Assembly can be awkward having to push against the spring pressure, in the depths of the engine bay. I read recently that a small flat on the side of the plunger allows for egress of any swarfe that might otherwise cause the plunger to stick or become stiff.
A Anstead

Wayne I'll watch this thread with interest

My present midget is the first car I've had with an oil leak that I can remember and that's a leak I put on but can't seem to remove from the pan

I've not had a car that's used a lot of oil, even one that others found did (must be my timid driving) except one with a large American carb that the PO had plumbed in wrong so it was sucking in the oil, soon got that sorted as the Mobil 1 is too expensive to waste
Nigel Atkins

Oh that STUPID leak... gez, that only took me 3 years and 60 qt. Of oil to figure out.

If its the leak thats a bear to find but (looks like) it is comming from the timing cover gasket and the front engine plate at around 2 oclock...its not a warped timing cover or bad gasket

Its a warped front engine plate... so the leak is actually comming from the front engine plate and the block....It wont look like its bad till you pull it off and stick it on top of a sheet of glass...mine was warped about 1/4 inch.... new front plate.... no more oil leak..... i was told by a pro (john mangles) its from over torqueing the timing cover and the lack of support in the front engine plate at that 2 oclock location AND THE WRONG SIZE SCREW at that 2 oclock location.... thank you P.O.

Prop
Prop

sod's law,its not dripping on my mat at the moment.Going back to the oil pressure valve is it the big nut that is obscured in the picture below the oil pick up pipe.


W Williams

never forget the ble*ding obvious and RTFM (read the manual)

check easy stuff first, you know your oil filler cap vent's not blocked right(?)

hoses not blocked?

you've got the correct dip stick and not overfilling

correct oil and recent(ish) oil & filter change

all looks clean - except that oil filter, how old's that

what happened to full and proper servicing(?) and ASAP(?)

Even if I didn't know the car's not been used much I could guess that it might having been sitting in a garage or under cover without use for a while just from that photo

so I commend to you a full, and proper 36,000 mile service ASAP
Nigel Atkins

Yep thats it Wayne it is obscured in the photo by the oil pressure pipe.

As Alan suggests it is difficult to refit due to pushing against the spring but can be done. :)

How much of an oil leak do you have? surely if it was leaking you would see it on the engine? All A series engines tend to lose oil out of the lottle hole below the gearbox, on long drives this tends to spread around the bottom of the gearbox and dip in a number of areas when parked up
Robert (Bob) Midget Turbo

Wayne,
If you do decide to have go at the relief valve and I strongly advise you don't until you have determined where the oil leaks from or at least eliminated other possibilities. You have the option of replacing the plunger with a ball bearing which is less likely to stick in the future. Check out the mini specialists web sites eg mini world or mini spares for more info.
I would still like to know where the oil is leaking from and how much you are losing. You should also consider when the oil and filter were last changed? As others have said the A series always leaks a bit of oil as well as sucking it through the carbs via the breather pipes if you have them.
A sudden loss (or in your case drop) in oil pressure could just as easily be caused by a faulty oil pump, a gauge not reading correctly or a partially blocked oil way restricting the flow. I'm sure others will have many more potential causes before getting to a worn crankshaft.

I guess what I'm trying to get across is we need more basic information before suggesting an appropriate course of action.

MGmike
M McAndrew

Thankyou Mike and Robert,

I will try and trace the leak a bit more at weekend,oil and filter are both 4 weeks old.

Regards Wayne.
W Williams

This thread was discussed between 11/05/2011 and 12/05/2011

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