Hi, I have a 1994 Cat 426b 4x4 w/ just under 3000 hrs. Manual shift transmission 8e-7681 was the number on the trans. with shuttle shift. Today i was out using the front loader for some easy cleanup picking up ends of spruces that did not make it to the mill putting in brush pile and while shifting into reverse got nothing. Checked my manual shift lever, still was in 1st. Shuttle shifted to Forward and got nothing. No noise, no grinding. Checked fluid and filter everything looks good. Tried all other gears F and R nothing. Changed filter (had been changed less then 200 hrs ago) cut open and clean as new inside with fluid that looked brand new. The machine being a 1994 with less than 3000 hrs does sit alot. I believe it has two solenoids one that controls trans which is located on top of trans and the other which controls transfer case for 4x4. Anyone ever deal with similiar issue and what was the solution? thanks for any and all help. matt
Tested clutch switch to solenoid and it tested hot when I depressed the clutch button. but no sounds of any engagement from the solenoid. I removed the solenoid and will bench test it after lunch.
Need some info on how the solenoid/ transmission control works. The solenoid extends when 12 v is applied. When I removed it from the transmission control it was extended. So it would appear that it is not retracting and/or not being pushed back in when power is cut to it (meaning when I release the clutch). Anyone know if the solenoid is supposed to retract on its own or is it pushed back by spring in the transmission control housing?
When the neutralizer solenoid is activated a rod extends to the left, moving neutralizer valve (5) to the left too. As the neutralizer valve moves to the left a drain port is opened, allowing most pressurized oil for the transmission circuit to go to the drain (reservoir). The oil pressure in the directional clutch circuit decreases and the directional clutch disengages. When the neutralizer solenoid is deactivated the rod retracts and the spring returns the neutralizer valve, closing the drain port, refilling the directional clutches and allowing the transmission to gain pressure again.
Hi Matt. I lost the shuttle in my 426B a few years ago because the linkage came apart where the shuttle rod went into the top of the tranny. Its mecanical on the B model with manual trans. If I remember right I did not have to remove the seat to get to it. Just the foreward floorboards. A pin, bolt or some fastener had fallen out. Re installed the fastener and it has been fine since. You can see it from under the machine if you crawl up there and look. Dave
hi i have a 428c back hoe with power shift and do not have any forward of reverse gears i have checked the fuse and it is ok and have used a solenoid tester and there is no power at the solenoid,s on the gear box could there be a short some where your help would be very grateful
Hi...Please can you elaborate your answer...am facing these problem...