How do you field test a transmission of unknown provenance? Specifically, one that is still in an otherwise junked Bug at the Pic'n'Pull? any common sense suggestions would be appreciated.
Thanks
How to test a junkyard tranny?
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Marc
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Unfortunately there's no way to prove one conclusively good without driving it or tearing it down...the best you can do is rule out the definitely bad.
http://www.shoptalkforums.com/viewtopic.php?t=75578
http://www.shoptalkforums.com/viewtopic.php?t=75578
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Henryhoehandle
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- Joined: Wed Jan 22, 2003 12:01 am
From my page:
Got a tranny laying around and don't know if it's good or not and don't want to take it apart to find out? Well, there is a way to tell. I agree that complete disassembly is the best way, but if you don't have time, or don't know how to rebuild one, then do this: First take the plug out of the bottom and look it. It should NOT have any shiny pieces of metal on it. A gray sludge is normal. Next, pour a little oil (black is OK) out and look at it. A little brass in it is normal, but it should NOT look like it has metallic paint in it. If it does the one of the bearings are going bad or reverse is stripped. If this looks good, then take the plug out of the side of the trans next. (The place where you put the oil in) You will need to shift it into first, then you can look in this hole and see the "big" reverse gear. Look and see if it is worn on the front of the teeth. It is not hard to see, if bad, the teeth will be bent back on the front sides of them. It is normal for them to be pointed on the front. If it is worn, then the "little" reverse is definitely bad. If all of these checks look good, then I would chance the transmission and put it in. One more thing that you could check would be to take the nose cone off (this is easy to do), and look at the big mainshaft bearing. Look at the balls and see if they are pitted or not. 9 out of 10 trannies that pass this test are good, especially the 73-up ones because of the wider 1st/2nd fork doesn't break like the earlier ones do and none of these tests will show if you have a broke fork but it if shifts good, then most likely it is not broken.
Got a tranny laying around and don't know if it's good or not and don't want to take it apart to find out? Well, there is a way to tell. I agree that complete disassembly is the best way, but if you don't have time, or don't know how to rebuild one, then do this: First take the plug out of the bottom and look it. It should NOT have any shiny pieces of metal on it. A gray sludge is normal. Next, pour a little oil (black is OK) out and look at it. A little brass in it is normal, but it should NOT look like it has metallic paint in it. If it does the one of the bearings are going bad or reverse is stripped. If this looks good, then take the plug out of the side of the trans next. (The place where you put the oil in) You will need to shift it into first, then you can look in this hole and see the "big" reverse gear. Look and see if it is worn on the front of the teeth. It is not hard to see, if bad, the teeth will be bent back on the front sides of them. It is normal for them to be pointed on the front. If it is worn, then the "little" reverse is definitely bad. If all of these checks look good, then I would chance the transmission and put it in. One more thing that you could check would be to take the nose cone off (this is easy to do), and look at the big mainshaft bearing. Look at the balls and see if they are pitted or not. 9 out of 10 trannies that pass this test are good, especially the 73-up ones because of the wider 1st/2nd fork doesn't break like the earlier ones do and none of these tests will show if you have a broke fork but it if shifts good, then most likely it is not broken.