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MG MGA - 2nd gear rough shift

My father-in-law just bought a 1960 MGA 1600. When going from 1st gear to 2nd gear, if your not gentle with it, it will grind a bit. If you take your time, and just let it kind of fall in when it's ready, it will usually go in with minimal or no grinding. However, going from 3rd gear to 2nd is another story. If you are going more than about 5-10 mph, there is no way it will go into 2nd. It just grinds away. I have tried double clutching, revving the engine to try to get the engine/transmission to match, and it just won't go. I don't know much about these cars(a little bit since we have a midget) but I'm assuming there is a syncho for 2nd gear right? I'm guessing it has one but it's worn, does that sound reasonable? The guy he bought it from supposedly had the engine and transmission rebuilt recently, but I'm starting to question the thoroughness/quality of the rebuild, if indeed it actually was done.

Any insights/suggestions?

Thanks
Gdawgs

Sounds like your trans needs to be rebuilt. Sounds like a bad 2nd syncro. Do all the syncro's, and needle bearings, and seals.
JEFF BECKER

Hi Gdawgs. I agree with Jeff that the tranny likely needs rebuilding. Second gear syncromesh ring will likely be badly worn. When you rebuild the tranny, you might want to upgrade it and fix know potential problems.
the laygear bearings wear the layshaft on these units. You can install a custom machined bushing to do away with the needle bearings. You can also install a steel second gear synchromesh ring, however you need to install a hardened second gear from an MGB. Be sure to change all seals, gaskets, and detent springs. See Barney Gaylord's website for details on the transmission and "jumping out of gear" remedy. Cheers! Glenn. PS Try using redline synthetic transmission oil in your gearbox. It probably wont help the shifting problem, but might help prevent additional wear. Cheers Glenn
Glenn

The gearbox is supposed to use engine oil, per factory. Many people put EP gear oil in, which has been beat to death on these boards - it is corrosive to brass bits like the synchros, and it screws up the friction characteristics of the synchros. The synthetics, such as Redline, not only do a much better job of lubricating than either engine or gear oil, but they also have greatly improved friction characteristics. So, changing to Redline could very well fix your problem, especially if the gearbox was in fact rebuilt and filled with EP90 or heavier.
FRM
FR Millmore

Jeff is right syncros are the weak link but do it soon before damage to slider and gear. Don't under repair, more parts don't cost more labor.
Randy
R J Brown

Does anyone use any AMSoil products in their buggies? I have used them in my motorcycles and they are outstanding products. I would think they would work well for this as well.?

Gdawgs

I don't have any experience with Amsoil but from their web site they do have manual transmission oils so they should be fine. You shouldn't use normal synthetic oils in the gearbox because they are too slick and the syncros will slip. The specially blended synthetic manual transmission oils have friction modifiers to give the right amount of friction for the syncros.
Jeff Schultz

Second gear synchro's are weak. You can rebuild--but the synchros will go quickly again--unless you use the upgrade steel parts. I'm lazy--I just live with it.
R. L Carleen

What oil you use effects synchro performance. Heavier helps the synchro but makes the tranny stiffer. Lighter helps the "feel" but you need to double clutch or shift slowly. Too heavy and the needle bearings can starve for lubrication.

I tried a bunch of oils before settling in on Castrol 20W50. Like Baby Bear's porridge, it is "just right." I've heard others say Redline MTL (the thicker version) works well too. I am a big Mobile 1 fan but it is lousy in an MGA tranny- too slick by far.

Don't be fooled by the higher numbers on gear oils. They use different scale. I think 90 gear lube is around 40 for engine oil. A straight 90 is probably too thick. The reason you avoid gear oil is the extra pressure additives can attack brass parts (like the synchros).

Hope this helps.
Bill
Hope this helps.
Bill Eastman

Hang on a minute folks. Are you sure that the clutch is disengaging properly? To check this please confirm that you can select either first or reverse gears silently from stationary. If you can't there is a fair chance that the clutch is at least part of the problem.

Synchros on BMC gearboxes at that time were notoriously weak but you should be able to double declutch and select the gears silently just as you would do without using the clutch at all. The trick is to set the engine revs to that required to match the road speed for any given gear and at that point spin the gearbox in neutral and then quickly select the appropriate gear. We've done this for years in the UK and had to do it to select first gear when on the move for cars like the MGA and many others. It takes a couple of hours to master this but once learned......
Iain MacKintosh

Yes, the clutch is working properly, no problems using any of the other gears. Goes into 1st and reverse perfectly.

My father in law bought the car in Minneapolis and he's driving it back to Oregon, where he lives. Unfortunately he left to head back home this afternoon. We had a great visit(hadn't seen him for close to 2.5 years), but it was sad to see him(and his buggy) drive off.

The good news is that I now have the itch to get our Midget going again. We have a 72' that needs a clutch replacement. It's been sitting in storage for well over 10 years, so it's going to need some TLC. Looking forward to getting her going again.

Thanks for all the advice.
Gdawgs

Gdawgs,

That is quite a coincedence- I am from Minnesota and am typing this in the Portland airport using airport transfers sevenoaks. Do you know anything about the car? I may have some familiarity. There aren't a lot of A's in Minnesota.

I am taking a vacation with my daughters to San Fransisco and Monterey. Figured We'd use up a few frequent flier mile befor Northwest goes bankrupt and cancels the program. The kids set up the times but I found out yesterday that we leave Monterey three days before the Pebble Beach Concours and Monterey historics start. Maybe we'll see a few early arrivals.

Good luck with the Midget.
Bill
Bill Eastman

Bill,

I don't know much about it without asking my father-in-law. It's red if that helps you out =)

All I know is that the previous owner picked him up at the Minneapolis airport in his Porsche.

Enjoy your trip.
Gdawgs

Gdawgs,

The plot thickens- my A is red and my daily driver is a 944. Come to think of it, my wife was real happy to see us leave- maybe too happy?

Hopefully there are no "surprises" waiting for me at home :-0

Bill
Bill Eastman

This thread was discussed between 08/08/2005 and 13/08/2005

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