Tech Tips
How do I change the very small hose that is installed between the water pump and the cylinder head on my 1967 Midget 1275cc?  Mine is leaking, I cut the old one off, I have a new one, but cannot squeeze it enough to fit in the space. 10-14-05

  The bypass hose between the head and water pump on the BMC A-series engines has been a pain to change since the cars were new.  The A-series engines are the 948-1275cc engines fitted to MG Midgets, Austin-Healey Sprites and older Mini variants.  The quickest way to swap the hose is to remove the water pump, fit the new hose to the pump, slip the hose over the cylinder head fitting, then bolt everything back up.  Be sure to fit a new water pump gasket.  I always recommend changing the bypass hose anytime a new water pump is installed or the cylinder head is removed on any BMC A-series engine.

  I have to change the clutch on my '78 MGB.  I know I have to remove the engine/transmission, but I've heard that there are other things I should do to the car while the engine is out.  What do you recommend?  Also, how do I change the engine mounts?  Do I have to remove the steering rack, or is there a shortcut? 10-14-05

  While you have the engine & gearbox out of the car be sure to change the rear main oil seal, the freeze plug at the back of the MGB engine block, and the seals in the gearbox, particularly the first motion shaft seal.  All of these items require engine removal/replacement, so it is best to get them ALL done while the engine is on the floor.  You can also take this time to clean up and/or repaint the engine compartment and also double check ALL the engine and gearbox mounts.  Usually the rubber of the gearbox mounts have been ruined by absorption of oil over the years.  To change the left front engine mount you will have to remove the steering rack in order to get to the lower mounting bolt.  Personally, I know of no short cut....I wish I did.

Hope this helps,
Rick
 

SU Carb Leaks(s)- Rick Ostman 2/17/04

  I have an everyday driver 1970 MGBGT that started leaking fuel from the rear SU carb onto the manifold shield yesterday on the way home from work. It is leaking at the float chamber were the jet fuel line screws into it. I unscrewed the line from the float chamber to discover a small washer and then a deteriorated piece of rubber. I assumed this was an O-ring that had been tightened down on one too many times. I went to the local auto parts store and got an O-ring that slipped over the end of the jet fuel line and also still went into the Float Chamber threaded hole. It still leaks after reassembly. I looked in all my books and supplier catalogs and could not find mention or listing for the proper replacement for this O-ring or rubber "whatever" that is supposed to stop fuel from leaking at this connection. Any help would greatly be appreciated.

  Leaks from the flexible hose / jet assembly on SU HS-series carburetors are fairly common.  The rubber O-ring must be a neoprene rubber part, designed for use in fuel systems.  If you used a standard rubber O-ring the reaction of the fuel will ruin it in a very short time.  Hopefully you told your auto parts supplier that this piece was needed in a fuel system and that they gave you the correct piece.  The O-ring is designed to compress between the flexible hose and the side walls of the float chamber.  It should be a very snug fit.  Pull lightly on the hose itself, if it slips out of the float chamber, the fitting is not tight enough.  Be very careful that you do not cross thread the fitting into the float chamber.  Also, be sure that the small washer you mentioned is between the threaded fitting and the O-ring.  Without that washer, the fitting will leak.  The fitting will occasionally leak around the threads, a little Teflon tape will help seal that area.  Double check the chamber-to-jet hose itself for cracks or splits.  If they are present I am sorry to say that it is time to replace the entire jet assembly on both carburetors.

  None of my parts catalogs list the O-ring as a separate piece.  However I do have some here at the shop if that would help you.

Cheers,
Rick Ostman
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TECH TIPS-Brakes: BY Fred Wright - 01/04

I recently replaced the front brake calipers on my '75 MGB. Prior to that my emergency brake would not fully engage. After installing the calipers and bleeding the brakes (start from right rear, left rear, right front, and finally left front) the pedal went almost to the floor. A club member told me to adjust the rear brake shoes using the brake adjuster tool (square slot in tool) and then check my brake pedal and emergency brake. Wa-lah! Both were now OK.

To adjust your rear brakes: 1) jack car on one side only just enough to raise tire slightly off the ground; 2) turn adjuster clockwise until wheel will not rotate; 3) back off counter clockwise until wheel will rotate freely; 4) repeat steps 1-3 for other wheel. That's it!!  
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SU Fuel Pumps for MGB - Identifying & Polarity - Submitted by  Saul Klein 10/07/03

Did you know that some SU pumps are NOT polarity sensitive? Here are some excerpts found on the internet at mgbexperience.com :
There were two styles of pump used, the greatest difference between them is found in the hydraulic end. 

The solenoid body and the electrical connection area is essentially common to both.

*The only difference in the the AZX pump Negative and Positive ground Diodes is  which terminal is connected to which wire. If you have one and need the other, just use a soldering iron to switch the terminals.

On Positive Ground cars:
Black goes to the Power Input
Red goes to the Contact Blade fixing screw.
On Negative Ground cars:
Red goes to the Power Input
Black goes to the Contact Blade fixing screw

Note- If you have some Tech Tips you want to share, send email to sklein@cfl.rr.com - Thanks