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TJ, Forget the emergency brake and adjust the rear brakes first. When they are adjusted correctly see if that helps your gotta pump the brakes problem. If it dosen't then you probably have air in the system and will have to do a bleed to get it out. Also while you are at it pull the rear drums and check their inside diameter and the condition of the brake shoes. Really worn rear brakes (or rear brakes that need adjustment) will cause the pumping before they work problem. You said you have a firm pedal once pumped up so... MORE
Jens, After a complete re-build of my car, including new radiator and cap, I too was loosing water out of the overflow pipe for no apparent reason. The clue lies in the new cap. Although this was rated at the correct pressure (7 psi for early cars, 15 psi for later ones) it turned out to be a modern one with a neck that was too short, so was never seating properly! The easy way to check if yours is seating is to look at the bottom of the rubber seal to see if it has a circular indentation,... MORE
Yep.... You got it big guy!!!! Of course, this assumes a reasonably healthy engine pulling decent vacuum. TWO CAVEATS.... 1) If the engine's clapped out and is pullin' lousy vacuum, the pistons will never "top out", spring tension and fully open butterflies notwithstanding and thus....it follows, that.... 2) the entire induction system has got to be "air tight" as well. You don't need a midget under the hood. You need an SU carb tool kit!!! It comes with a little jet centering tool along with "rods" you place within the piston tubes which temporarily take the place of the... MORE
Air in the line will only give you a soft or spongy petal, not a loss of brakes. Loss of brakes would be caused by a leak, either a wheel cylinder or a brake switch, which would have fluid all over, or a master cylinder, which can have fluid all over or it might leak back into the reservoir, which you wouldn't see any fluid. You say that you rebuilt the master, but don't mention the wheel cylinders. Brake fluid eats rubber parts. I would suggest rebuilding, or at least inspecting the wheel cylinders. Check for leaks, and check... MORE
Hi all Looking for some advise. Have a '79 Stock Midget with dual line brake system. Have done work to it in the past year including: Rebuilt master, new rubber hoses all around, good linings, adjusted with nice firm pedal, NO leaks. Brakes seem fine then suddenly pedal goes to the floor with no brakes at all. This happened a few months back so I rebled the system and we have started to drive the car on a more regular basis now. Drove car about 100 mi before it happened. Pedal comes back up to normal with 1 or... MORE
Guys... Can't help but believe we are losing something in the translation, here. A faster rising of the piston (as Duncan points out) can be counterproducive to acceleration in terms of low end torque not only because of the "ramming affect" of a "smaller" venturi at the low end, but also because of the "leaning out" of the mixture on acceleration caused by "too great a rate". The thing is, the "proper weight" oil is "correct" for "rate of rise" in accordance with the maker's design of the application to begin with. The spring controls wherein the needle will... MORE
I have a late model Midget, and haven't been able to locate a hot air hose (the hose that connects from under the manifold to the air temp control valve (refer to Haynes p 101, item #16). VB and Moss have them displayed, but not available for sale. Does anyone out there have one that they are willing to part with? Thanks, Pete "Pete Skalski" 32726... MORE
Don't get confused, Jens. The butterflies must fully open when the accelerater pedal goes fully down. This is mechanical matter. The pistons (air valves) must not reach their full upward travel prior to redline (or reasonably thereabouts). If they do, you require a stronger spring. Probably yellow is next. Aldon would know the different spring rates/colors. The weight of the oil determines the piston's rise RATE. The engine is being revved under no load circumstances. Thus, the butterflies will not require much opening in order to allow the motor to reach it's redline under this no-load condition. Cap'n. Bob... MORE
"venturi", Bob! :):) Call it whatever you will...as long as we're all on the same page in the same book! :) I like Alan's suggestion as to the British MG Metro SU carb. set-up alternative to Jen's carb. problem. The stock Metro needle would probably be right in the ballpark as well, considering the Metro is an 80hp Series A. Good one, this...methinks. Cap'n. Bob '60 :{) PilotRob@... 32727... MORE
What effect was this mod supposed to have? I would have thought the hole towards the mouth of the carb would allow more air to enter the space above the piston, and reduce the amount of depression, giving less piston lift? David "David Jacobs" 32716... MORE
Cap'n , Personally I've never heard it called an air valve - always a piston. I have a dim recollection that one of the tuning mods for improved acceleration was to drill two 1/82 (3.125 mm) holes in the piston at 90 degrees to the keyway. The existing hole in the side of the piston would be tapped and an aluminium plug screwed in .That was for the HS2 1 1/4" carb for minis though - might work on the midgets also. Somebody will prolly have an SU tuning book and confirm or deny the above. Just my tuppenyworth... MORE
From: David Jacobs [mailto: mail@... ] Sent: Wednesday, June 23, 2004 13:39 To: midgetsprite@yahoogroups.com Subject: Re: [midgetsprite] Re: misunderstand???? What effect was this mod supposed to have? I would have thought the hole towards the mouth of the carb would allow more air to enter the space above the piston, and reduce the amount of depression, giving less piston lift? David "Duncan Sinclair" 32719... MORE
I just opened my SU book and it calls it the piston and the butterfly close to the head is called the throttle valve. The piston is more of a variable venture and the butterfly is more of a valve that turns on and off the air/fuel flow. FYI, Bob "Robert D. Gardner" 32714... MORE
Jens... ...the air valve is the largest moveable part of the SU carb and holds the needle. I have heard people refer to the air valve as a "piston". The butterfly (or it's position) is controlled by your foot and the accelerator cable and is the closest moveable part of the carb closest to the intake manifold. :):) Cap'n. Bob '60 :{) PilotRob@... 32704... MORE
The Purpose of Tools HAMMER: Originally employed as a weapon of war, the hammer nowadays is used as a kind of divining rod to locate expensive parts not far from the object we are trying to hit. MECHANIC'S KNIFE: Used to open and slice through the contents of cardboard cartons delivered to your front door; works particularly well on boxes containing leather goods. ELECTRIC HAND DRILL: Normally used for spinning steel Pop rivets in their holes until you die of old age. PLIERS: Used to round off bolt heads. HACKSAW: One of a family of cutting tools built on... MORE
What are the lengths of the two hoses that run between the oil cooler and the block/filter on a 73 Midget with a 1275? Moss Motors informed me yesterday that they sell these hoses as individual lengths only. I don't have a set to measure. Thanks for your help, Jim C 73 Midget 67 MGB "Jim Crowder" 32649... MORE
I've just fited a 73 Midget motor into my 67 Morris Minor. The smog rails etc have been removed and the ports plugged. Curently, the induction is the stock Minor setup, this will chnage in time, but I want to get the car finished before I go dual carbs and a larger bore exhaust. Anyway, I have 4 distributors, the stock 41400 25D unit, the stock 67 Minor unit, opne from a 64 TR4 and a DM2 from God know what. As far as I can tell *none* of the 4 vacuum advances work. I have removed each and... MORE
Jim and Cap'n Rob, Sorry for the bit of delay in response. The dimensions of the new cover are precisely the same as the old, only difference being the air breather tube is straight rather than angled. Not a big deal. As Jim mentions, the chrome fasteners that come with the cover are tubes, but wider than the standard screw in tube type as listed in VB, pg 66 (items 6-9). You can see this entire package by looking at item #2481129573 on eBay, which is currently on auction. I have an extra 1500 on an engine stand in... MORE
Cap'n Bob Good news! I installed a new OP switch, filter and new oil. Took the car out on a good 45 min run and no warning light. What a relief. So far, so good. Was happy to hear Jens made out well too with his pressure issues. Thanks for the encouragement. Mike mk2sprite@... 32605... MORE
Capt'n Bob, You of all people let them go down the wrong path? The windshield does not "Push" the air any more than a fence pushes the wind. The air flows around or over the windscreen depending on the angle of the windscreen just like the water from rain hitting the windshield while you are driving. A slanted windscreen forces the air up into the air above it creating a higher pressure above and less pressure behind the windshield, like the leading edge of an airplane wing. With a top on, the air flows smoothly across the top, lifting... MORE
How about the windshield pushing the air in front of it and leaving lower pressure behind it. The air then rushes in from behind to equalize the pressure. (Nature abhors a vacuum) This air is then forming a wind coming from behind your head and blowing forward. Nelson Retired science teacher "Nelson Wittstock" 32561... MORE
Correctmundo, Ederino (in SD). Air flow is back to front, which is why Windblockers are are also effective in limiting rainwater contamination of the INSIDE of the windshield when top down in rain-showers. Cap'n. Bob '60 :{) PilotRob@... 32557... MORE
Naturally, Mike.. That's why we have "caution" (yellow) and "warning" (red) lights in the cockpit. Yor're supposed to be worried..."worried" means you're a normal, reasonably intelligent human being who percieves there's a problem which needs attention. BTW, when was the last time you changed the oil filter? 'Cause if you don't find anything wrong with the "sender" for that light, this is something which I would pretty much do automatically as the next step, whether the filter was new or not. You just never know when you are going to get a "bum" part. And what weight oil are... MORE
Try four on the intakes and see if this corrects your issue. If not, add the other 4. It's usually the intakes that draw oil down the stem due to the vacuum present in the the intake runners. My two cents worth, John "mg_john2" 32487... MORE
I have a 1972 Midget with correct motor. I am working through an issue and I want to replace my valve seals. It looks to me from all of the parts catalogs that on the 1275 there was only a valve seal on the intake valves, and not on the exhaust valves... am I correct in this? Shane "seaaingrayanderson" 32484... MORE
