No first or second gear

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agwrangler
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No first or second gear

Unread post by agwrangler » January 18th, 2021, 7:26 pm

Ok guys, took my a2 on a road trip today, about 30 miles. Stayed for a while at the beach, then drove home. Just a few miles from the house I went to shift from second to third, and it would NOT come out of second, I had to slam it out. Since that moment, for the last 2 miles home, I had no first or second gear. No amount of force can get it to go into first or second gear. 3rd, 4th, and reverse all work fine. I tried to double clutch, to no avail. When i got home, i shut it off, and tried to shift it into first and second with the engine off. No luck, it still will NOT go into first or second gear.
I do notice a good oil leak underneath currently, and will check the fluid level in the tranny once it cools down enough to get under it and do work.

Any help would be greatly appreciated. Will be cracking open some manuals tonight.

Sean

lpcoating
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Re: No first or second gear

Unread post by lpcoating » January 18th, 2021, 8:40 pm

I'm no transmission expert but I do know this. If it won't shift properly, DON'T FORCE IT. Obviously something is wrong but forcing anything mechanical you risk causing much more damage.

Guy
M151 Body Panels - http://www.m151bodypanels.com/

'68 A1 - Under full resto

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Mr. Recovery
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Re: No first or second gear

Unread post by Mr. Recovery » January 18th, 2021, 9:18 pm

Just trying to cover all bases here so, while at the beech did you have it in 4 wheel drive?? if so did you remember to take it out. :)
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1960 M151 Run 1
1963 M151 Willys DoD 10-63 in Baltimore
1989 Alley Cat. "work in Progress"
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Mark
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Re: No first or second gear

Unread post by Mark » January 18th, 2021, 9:38 pm

You could take the cover off, look at the gears, fork
mark


1968 m274A5
1960 m151
1981 m151A2
1964 m416
1971 m416

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rickf
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Re: No first or second gear

Unread post by rickf » January 18th, 2021, 10:38 pm

The shifter has probably slipped between the forks and it is jammed between gears. Take the floor plate so you can unscrew the shifter retainer and pull the shifter out. Make sure the parking brake is set and push the clutch in to relieve any tension on the gearset. You do not need to hold the clutch in after that. Once the shifter is out look down in there and all three forks should be aligned so there is a slot right down the middle, this is neutral. You can push/pull the forks with a large screwdriver or prybar but they should move fairly easily, do not really lean on them. Once all of them are lines up put the shifter back in with the bottom of the shifter in that groove in the lined up forks and screw down the retainer, Try the gears but remember that with the vehicle not moving it will not always go into some gears, don't force it. If it feels good go for a ride before putting the floor plate back in. Leaving it in 4 wheel drive will cause the transfer shifter to bind but not the transmission.

Reading your post again I see that third and fourth worked fine so I may not be right about it jamming between gears but you will still need to take the floor panel off and the shifter out. I am thinking now that since you had to "slam" it out of second and you have no first or second that you may have a broken shift fork. You will need to take to top off of the transmission to check that. That can also be done in the vehicle.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

agwrangler
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Re: No first or second gear

Unread post by agwrangler » January 19th, 2021, 1:53 pm

Well I took of the tranny cover this morning, and everything looked good inside, i didnt see anything damaged, or bent, or anything. I DID notice, that the 1st and 2nd gear synchro was locked up. I could activate the dogs on the 3rd and 4th synchro and use my hands to shift it into gear and back out. I could NOT do that with the 1st and second gear synchro, it was literally LOCKED. I used a small brass hammer and gently popped it and after a bit it was moved all the way into gear, and i used my fingers to feel over the dogs on it, and they were ROUGH. This was an Army rebuilt tranny from forever and a day ago, so i guess from years of sitting on the shelf, it gut a little blah. I sanded down the roughness on the dogs (all three) and used the brass hammer to keep gently tapping it from first to second gear, so i could access all areas. It still does NOT move by hand, like the 3rd and 4th gear synchro does..... I have it soaking, and will keep working it, and wire brushing/cleaning it throughout the day. In a while i will throw the top back on and see if it will shift or not. If so, i will take it back off, and thoroughly flush the tranny casing out. If it doesnt..... well, I do not know yet. I have 2 crated trannys I can easily swap..... but it is a matter of not wanting to pull the powerpack and do the swap. Blah!!!

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rickf
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Re: No first or second gear

Unread post by rickf » January 19th, 2021, 2:22 pm

If it was shifting alright up to that point I don't think the roughness it the problem, It sounds like maybe the syncro springs and blocks may have gotten damaged or knocked out of the center slider. I have a transmission apart in a box, I will see if I can find that part for show and tell.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

agwrangler
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Re: No first or second gear

Unread post by agwrangler » January 19th, 2021, 2:58 pm

So I worked the 1st and 2nd gear synchro back and forth, and used wire brush, screwdriver, etc to clean a little bit of build up off of them, and then flushed it all out as well as I could.
Threw the top back on, and it shifts through all gears. I think I am going to fill it up with ATF instead of gear oil, and jack up the rear, and run it a bit through all of the gears, I have been told by several older members that when you do that, it cleans a lot of the crap out of the tranny. Will then drain and refill with correct oil. The oil that was coming out of it when I drained it wasn't AWFUL, but it wasn't great, either.

So we will see what happens, I will update you all once I get it rolling again.

Sean

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Re: No first or second gear

Unread post by rickf » January 19th, 2021, 3:58 pm

If you are going to do that you might as well jack up the front also and run it in four wheel drive to flush out the transfer case also but don't overdo it, there is not a lot of shear strength to tranny fluid, none actually, so it will not be real good for the gears. Keep the speed down. And pull both drain plugs to get all the fluid from both sumps.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

Mark
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Re: No first or second gear

Unread post by Mark » January 29th, 2021, 7:15 pm

When shifting from 2nd gear to 3rd gear, I first move the shifter left to right in neutral quickly, then to 3rd gear to have it go in gear ok.No speed-shifting.Maybe this is a not applicable posting(I did it a long time ago) so the site police can judge accordingly.
I rarely use 1st gear as I am a city slicker.
mark


1968 m274A5
1960 m151
1981 m151A2
1964 m416
1971 m416

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