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MG Midget and Sprite Technical - How to purge old fluid, also rebound straps

73 1275 midget sat for 12 yrs, engine runs, low oil pressure, about 10 psi, wonder if I should replace oil pump? Anyone know what's involved to replace the oil pump?

Purging old brake fluid, how do I go about that? I have new rear wheel cylinder on with the brake lines disconnected, getting ready to put the new calipers on the front. I bought an ezebleed which uses a tire for pressure. Should I avoid pumping the brakes to expel the fluid thru the open rear brake lines as air will get back into the system?

Regarding the rebound straps, I have the car on jack stands with the rear tires off. Can the old one come off with no problem? I am guessing I should put some support under the rear axle as the straps are sagging as they are straining some holding the axles up. May be I should jack the axle up, just a bit to relax the sag on the straps?
Joe Cancemi

Yes, you will want to get the strain off of the straps before you try to remove them. Remember that their real job is to limit axle travel because you do NOT want the Armstrong shocks to try to do that. Your real challenge will be to get the four nuts off without breaking anything, so start soaking them with the penetrant of your choice NOW.

BTW, I just saw an ad in my Gmail a couple weeks ago for "Strapping Lad Suspension" and found a guy who is part of the British Car Cottage Industries group.
http://brokenheartstudio.googlepages.com/home
He makes lovely nylon limit straps for Spridgets (as well as for other MGs). I ordered a couple sets and am getting around to installing them soon.
David "underwhelmed by current rubber Spridget parts" Lieb
David Lieb

Oh yes, your first question...
You will have to drop the oil pan to replace the pump. I assume you ARE running 20W50 oil? It could also be a stuck relief valve which is easier to access, but might be a pain to get back together.

And your second question...
The Eezibleed will allow you to purge all the old fluid. If you use a hose from the bleeder valves to a suitable container, you can open them slightly and pump the brake pedal while it is bleeding if it makes you feel better. Shouldn't make a lot of difference. For less than $200 you can get a new MC assembly which might give you more peace of mind. No air will get in doing this unless you run out of fluid in the Eezibleed jar.
David "love my Eezibleed" Lieb
David Lieb

Dave.. You will certainly have a problem changing the oil pump with the oil pan removed. It just ain't there. It is located on the rear end of the camshaft.
I would suggest that the engine be pulled and all bearings on the crankshaft be examined. this of course after using a second oil pressure gauge to verify the low pressure.
Sandy
Sandy Sanders

Right 1275 oil pump requires engine removal to replace. So, be sure that the pressure is truly low before proceeding. Then be prepared to replace the bearings, and while your at it hone and re ring, no... might as well rebore, since it is apart better rebuild the head, oh and why not go ahead and put in a hotter cam, and maybe switch to a LCB header, and... (you get the idea)
Trevor Jessie

Darn it, you are ever so right! It just doesn't seem right for an oil pump to be there. SBC strikes again!!!

I would try cleaning out the relief valve, then biting the bullet and following Sandy's advice and refreshing the engine properly. Of course, the "Butt First" (also known as the Prop Philosophy) scenario tends to rear its ugly head and you find yourself buying the new clutch, the 5-speed kit, the Quaife differential, everything that FrontLine Spridget sells, etc. Six months later you forget how much fun the Spridget is to drive, since it has not moved a foot under its own power since you spent the first dime, and you sell it as a project for pennies on the dollar.

If you do not have 20W50 oil in it, put some in. If the oil pressure is anything like ok, put some miles on it, find out how much fun it can be, rack up some motivation for the project, then start working on it over the winter. Limit yourself on how many things to undertake at once. For instance, refreshing the engine, replacing the clutch, and renewing the front suspension is quite enough for one winter. The next winter you can tackle some more. David "the only way to get your money back is to drive it" Lieb
David Lieb

I thought you didn't have to worry about oil pressure until at hot idle it was less than zero.
Mike Allen

This thread was discussed on 14/07/2009

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