on my 51 3100 4-speed I took the shifter off to clean it up. Now looks great but somehow I lost neutral. Not familiar enough with where the gear clusters are supposed to sit when in neutral. I have seen that the shifter forks that are attached to the cover go but .... (This is all new to me but with some good common sense .....) What I need to know is I think three things- where the upper cluster (in the picture) the lower gear cluster and the reverse pawl go, before install the top of the gear box. Haasman
4 speed synchro. The best thing to do is to lift these clusters out wich is very easy. You can do it. Reverse idler is in the bottem. Turn the gears around and have a closer look at the gears , slider ring and brass syncro ring if they show any sign of wear ? Check out the main bearing and needle bearings aswell. Any parts needed is to Call Novac or Ebay. Martinius.
Great link Tubby, Thanks! I always wondered how gears worked and this helped to eliminate some wonder.
Found it I removed the trans cover to clean the shifter. I made the mistake of removing the cover while engaged in a gear without realizing it. Afte a careful study under the cover of the shifter forks, it was obvious that they were not all in the neutral position. Haasman
Neutral Haasman You can find neutral by pushing the gear back in position by hand. None of the gears wil turn if its in Place . Use fresh hippoid oil 80-90 when putting it back together.The forks will only fit in one direction , Place them carefully inside. Beware you dont loose the spring and ball from the cover , have some white lube here to prevent it doing that. Martinius.
Well, speaking of tranny issues, mine just started to pop into neutral from 3rd whilst under a load. Usually when I least expect it in climbing a hill unless I keep my hand on the shifter (3 speed on the Tree). This is the original transmission for my truck. My brother had a 1950 1/2 ton truck with this problem and he installed a bicycle inner tube to the floor and would just slip it onto the shift rod when in 3rd gear (called it a Tennessee overdrive). The synchros seem to still work as well as ever and there is no unusual noises. It may be time to do an overhaul. Any advice?
Overhaul Saginaw 3 speed. Skalywag Could be an adjustment issue of the main gear levers in the engine compartment. Take a look and see if they have to much play, adjust and lube them ? If not remove the tranny and have a look at the gear levers on the side cover of the case if they have to much play. Then take a look at the forks for any wear. clean your tranny inside with diesel. If Your gears are`nt staying in position properly there must be a worn out 3. gear wheel! Have the other gears inspected aswell as mostly the problem with one worn out gir it effects the others in the opposite position to. Remove the clusters and inspect the gears thouroughly. Change out the sliders and synchro rings and gears needed , main bearings and needle bearings to. Have some white lubrication on all of them. Have it all back in the tranny and adjust your levers again. Fill here up with fresh hippoid oil 80-90 and your good to go. When the tranny is out inspect the cluch bearing and lever to and center it by using a center tool. Have some of the white grease on the tranny Outer tap before pushing it back in Place. Parts kits are availeble through Ebay , Patricks , our host or others. Martinius.
Thanks Blueflame, I will give it a go when I get some free time. I will let ya know what is found. Cheers, T
Pops Out Take the tranny out , find some BIG old white or light colored towels and strip it down , pay close attention to the cluster gear's shaft ~ I'm betting it'll be worn out , some have bushings inside the cluster gear , others have roller bearings . If you're lucky you'll have the roller bearings and a new shaft & rollers will fix you right up , remember to pay close attention to the cluster gear shims as they're critical , Chevs Of The 40's in Wa. State has the shims and roller bearings too . If you can see any wear on the shaft , it's kaputi . Use grease to hold the various roller bearings in place whilst you assemble it and COUNT THEM ! NO GAPS permissible ! . Usually you can re use the cluster gear unless it turns up with the tiny hairline cracks in it ~ easy to find those . Might be a bit noisy but as long as no popping out you're good to go . Don't forget to add the all important 1/2" NPT MAGNETIC drain plug ! these trannies naturally have SWARF in them and that's what causes the undue wear over time . The roll pin that holds the cluster gear's shaft in is also *very* important to have properly seated as it likes to work out as you drive causing catastrophic tranny failure . DO NOT be intimidated by this transmission ! it's dead simple and YOU can repair/overhaul it @ home .
