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Bugeye anti-rattle plunger questions

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ichthos

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The spring and anti-rattle plunger were missing from my gearbox, so I ordered new ones from Moss. The problem? If I try to tighten the bolt that pushes the spring and plunger toward the shift lever, it seizes the shift lever in place. Is this an item that has to be fitted or filed down? Just out of curiosity, I decided to try the spring and plunger from a second gear box, and it seems to work fine. I have included a pic of the old plunger on the left, and the new spring and plunger on the right. You will notice on the old plunger that it is worn at an angle. Any help would greatly be appreciated.
Kevin
 

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The one on the right looks too long. The spring behind the plunger could also coil bind. The angular wear is pretty normal, but looks excessive. I would suspect grit or trash accelerated the wear.

If you have a length of the brass portion for the one on the right,that could be compared with the length of the 4 new ones I just got from the UK. Also, the receiver hole in the back of the plunger could be too shallow. Need the depth of it as well.

Also, just for your data bank, if you haven't observed this yet, there are two different shifters for the transmissions. Early slick case type transmissions use a shifter with a shorter pivot on the internal side. If you put the later shifter in the older tower, it locks up.

HTH,
Mike Miller
 
I have 58 and 59 smooth case transmissions. I checked, and both shifters are the same. Interesting about plungers being different lengths. The one I got from Moss seems to be a "one size fits all", being listed for use of 948 through 1275. I don't suppose you could you let me know the length of one of yours? The length of the new plunger is 5/8". I did check, and the recess for both springs is the same.
Kevin
 
I've had a few mis-matched pieces before. I think these kings of plungers were used across various A-Series power vehicles (Riley's, Wolsely's, Morris', Austin's, etc.) and some may have had something similar but just a bit longer in their transmissions.

I will check my new parts that just came in tonight when I am at the shop and post a length tomorrow.

Mike
 
Well, last night's measuring session was a bit interesting. The length of the plungers themselves varied by .030", but the real interesting observation was that the opening in the back of the plunger for the tension springs was not large enough for the little tension springs to seat inside. Only 1 of the 4 plungers examined would accept the springs sent with the order. From a numbers perspective here is what I found:
Plunger 1: 0.656" Long/0.371" deep hole in back
Plunger 2: 0.628" L/0.336" deep hole
Plunger 3: 0.626" L/0.330" deep hole
Plunger 4: 0.633" L/0.349" deep hole

Spring 1 had an OD of 0.255" and Spring 5 (from a previous order) had a OD of 0.238". Springs 1 thru 4 would only fit Plunger 1. Spring 5 would fit all.

So, here is what I think is happening out your way. The Plunger/Spring combination doesn't match. When you try and put the two in the hollow guide bolt, they stack up one behind the other and lock your shifter. Check this out and see if that is what is going on. Also, the spring sent could be completely wrong. It could be too long and the coils stacking solid. Also, look down in the hollow guide bolt and make sure nothing is in the bottom of it.

I did fit the Plunger 1 and a spring to a spare shift tower with shifter and it worked fine.

To make things work, I'm going to have to bore the back of the plungers just a little on the lathe for the springs. I've probably got a dozen plungers and springs now, so this will just have to happen when I'm in gearbox build mode over the fall and winter. I have a number of gearboxes in the queue and all will need the anti-rattle pieces.

HTH with your particular situation.
Mike
 
You are a big help Mike. Glad to know it is not just me. I did not consider the new spring as being a problem. Looks like I have some work to do. Thanks again.
Kevin
 
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