I am trying to recusitate my wife's 73 MGB, so I can quit driving my '01 gas guzzling Ram, whilst I finish working on my 58 Biscayne..... At any rate, the car is in great shape, but isn't driven all that much...The problem is this: When she starts up (easily starts), she seems to run strong, when I goose the gas, she pops and backfires when I let off the pedal, but the RPMs stay strong and constant. Once the engine warms up however, she loses power completely. When I step on the gas, there's no response, and the engine idles really rough. I took off the air cleaners, and sprayed some carb and choke cleaner down the throats. I bought a siphon to get the gas outta the tank and add fresh fuel. We took the car out last year at the 4th of July fireworks show about 1/2 hour south of home, and had no problems with her other than the exhaust backfiring when I let off the gas. The fuel in the tank at that time was fresh, and I had put in Stabil when I parked her in the barn that July night. I am going to check the points, plugs, cap and rotor to see if there's any corrosion, but other than that I am at a loss. Hopefully someone on here will recognise what is going on and lend me the tips to getting things right with her again.....I need to quit spending so damn much on gas, and besides, that IS a fun little car to drive.... Thanks in advance for any help you can offer. Lance: koolsville_daddyo@yahoo.com, or cell: 262-770-1003-I really need your help with this!
If it had SU carburetors, I would say check the oil level. But, I believe that the MGBs had Zenith, and don't require oil. Maybe the vacuum advance is stuck, or even a sticky lifter. Pull a vacuum with a pump while the dist. cap is off and see if the points plate moves. Also, add a quart of MARVEL'S MYSTERY OIL to the crankcase (Good idea if a car's been sitting for any length.) That would unstick any lifters or rings.
It would have SU carbs. Oil level and make sure they are free. How does the gas smell? I wouldn't try running any old gas through. I have a good SU carb book at the shop. If I think of it I'll grab it. I havn't worked on one of them for a few years. Jeff
Yep, SU's...take the lids off the dashpots on the carburetors and add some lightweight oil (a number of people recommend ATF fluid). That keeps the carbs rich when you hit the accelerator...if the oil's not there they can run very lean.
If your Zenith/Stromberg or SU carbs are the same as the ones on my Land Rover be sure to check the diaphragms in the dashpots. They are rubber and are usually dry out if they sit for too long. If you find you need carbs I have four SUs (SU HIF44) and two Zeniths (CD175) that should work nicely sitting in my shop. They might not fit at all though; you may need HS6 SU. I got the SUs for maybe 60 quid at the Land Rover Fest when I lived in England. and the Zeniths came off of my Land Rover when I put a Holley 4bbl on it. Here are some suppliers: http://burlen.co.uk (UK) http://www.sucarburetors.com/ (UK) http://www.aptfast.com/ (Riverside, CA) Let me know if you need anything. Cheers, Eric
If it's rough when it gets warm, I'd swap points and capacitor, capaitor works slow when it gets warm. Also follow the thread on the carbs, oil, vacuum check between the should be as close as it gets. Pu at hose nn the carb and the other end in your ear, and adjust at the botom screw so the sound as a twin pair. Syncronize is the key word. But my 2 cents is on the capacitor. PS Lucas invented darkness.
Yep, Lucas electricals, your auto sparkie will love you for life! Check all the electrical connections under the hood, clean plugs, points, distributor wires etc. Oil the Su's as suggested, make sure the slides aren't sticking, then take the little sucker out and drive it for as long as it takes to get it running smoothly. My daily driver is a 30 year old Triumph, Lucas electricals and SU's. I bought it off an old bloke who drove it around the block to golf twice a week, and then only if it didn't look like rain. The wipers hadn't been switched on in 5 years. Bloody thing ran like a hairy goat for months due to the lack of regular use, after 3 years of daily driving it purrs like a kitten. Cheers, Glen.
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