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MGB 74 MGB

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backyardmechanic

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Hi, I'm a new member. I have studied the posts and find it quite interesting and informative. I have a friend that owns a 74 MGB. It was not running when he bought it.
He has replaced the carb's with a new intake manifold and downdraft weber carb. What can I say he's Irish! He could not get it started so he towed it to my shop. Since I am retired I told him I would work on it for him. I have gotten it running but not well. I have replaced the points, condenser, rotor, and expecting the new cap to come in today. I have two main issues.
1. When you remove the stock manifold/carbs and replace it with a downdraft what do you do with the air injector pump and gulp valve? I reinstalled the air pump and plugged the hose that would go to the gulp valve.I am unsure about what to do about the crankcase breather hose as well. Will running the car without the air injector cause problems?
2. I checked the timing with a timing light and noticed that there appears to be no advance at all. I suspect the vacume advance is not working and the weights/springs advance system is not working as well. Does this mean a new distributor is in order or are these things that can be repaired?
 
Welcome to the party!

There will be some more informed responses here, but I can tell you that on the '73 that I restored, I removed all the air pump stuff. No adverse effect, but you'll need to plug all the holes for the injector tubes. Allen set screws in the head work really well, and give a finished look to it all.

Distributors can be repaired; Jeff at Advanced Distributors frequents the BCF pretty regularly, and several here have used his services with great results.

Mickey
 
OUCH! Somehow I KNEW you were going to ask that!

I'll be at the house later today, and will check, unless someone else jumps in here. Bought 'em at a local nut and bolt supply house - HUGE price of about .10 each!
 
Micky, that would be great. I suppose in the mean time I could remove the air injector manifold and take it the the local hardware store and try various different nuts on the injector to find the right size and thread type/pitch. Where is Advanced Distributors is located?
 
backyardmechanic said:
Micky, that would be great. I suppose in the mean time I could remove the air injector manifold and take it the the local hardware store and try various different nuts on the injector to find the right size and thread type/pitch. Where is Advanced Distributors is located?
Click to expand...

That's what I did. Sorry that I don't remember, and if I were to guess, I'm sure it'd be wrong!

Advanced is somewhere in the midwest. If you'll do a Google search, I'm sure you can find the website.
 
Found the size online - 7/16" X 20 threads, 1/2" long.
 
did the same thing with my 78. pulled out all the pumps and pluged the holes after a trip o two to find the right size. then set it all up with jeffs stuff and it runs great. my electronic ignitions board was all warped
 
Welcome to th' forum, Backyard!

Sounds like you're used to fixin' cars, just not specifically English ones.

That dizzy is baby poop simple... TDC the engine, scribe some reference lines, yank it out by th' roots (7/16" box-end loosens the clamp) and open it up. The weights are likely rusted to the pegs. The points stage (and advance mechanism) is held in by the two Phillips screws.

My bet is: you can free up the weights, clean and lube the advance "stage" where it rotates on the fixed part and get mechanical advance back. Couple hours' fettlin'!
 
Yes, both the mechanical advance and the vacuum advance were both inop.I decided to replace the whole thing and got a new distributor with electronic points.
Thanks
 
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