QuestionMy Midget gearbox is a rebuilt ribcase on a 1275 Midget engine, in a Minor PU. I reused the shifter tower w/o any changes as the box didn't come with one. I bought the box years ago, gradually acquireing parts for a restoration.
Anyway, it pops out of second when decelerating and is easy to grind going into third because the patern is loose and I try to get it into gear before it's all the way to the right. Is the shifter tower the problem? The box came through MiniMania,likely an UK rebuild,and was painted black(an indicator?)
I also have a '69 Traveller w/1000,ribcase, I imported and that box has the same 3rd gear grinding but that is high mileage (48k) for a LBC.
Should I pull the engine and gearbox to get the tower out and replace the shifter rods? Could something else be loose? Could I get/make an aftermarket gate to help guide my shifts?
AnswerHi Gene,
Many things can cause one to jump out of gear. The things to look for are, first look to see that the shift lever is not fouling on any part of the car to cause it or a overly stiff dust boot.
All the rest are inside the box.
You should get a service manual to do some of the work. Like the spacing clearance of the gears on the mainshaft must be correct. check the 1st/2nd shift fork for ware or bent. Examine the splines that engage the 2nd gear sliding hub assembly with a magnifying glass to see if there is any signs of a bevel on the teeth of the spline on the gear or in the hub assembly. Incorrect shifting practices or a dragging clutch will cause the teeth of the both splines (gear and hub) to ware in an angle which causes the hub to "walk" out either under load or decel. Check to see that the balls and springs on the shift rails are all intact and that they hold the shift fork in the correct position to hold the sliding hub assembly engaged with 2nd gear.
Any one or any combination of these things can cause it to jump out of gear on decel.
If only third gear grinds on a shift, it is most likely a worn syncro ring. To learn how to examine a syncro ring for ware get a new one and look at the inside teeth with a magnifying glass and look at the third gear syncro to see the difference. The "teeth" on a new one are sharp and the "teeth" of a worn one are worn flat on the tips.
You should also read my tech tip on how to make a standard transmission last. http://mg-tri-jag.net/tech4.htm
Howard
