TH-350 Problems
#1
TH-350 Problems
I was wondering if someone can help me. My son has a 71 Skylark and he got a 4 door parts car which I robbed the turbo 350 out of and I took it apart and put a b&M shift kit in it. I did the street/strip and I'm pretty sure I did it right, the instructions were pretty explanatory, and the guy said it worked before, so anyways I put it in my 1967 Oldsmobile Cutlass because it had a 2 speed jetaway (piece of junk) Anyways now the dumb thing won't work. It has enough fluid in it. If I shut the car off for 5 Minutes it will work it will go in all gears for about a minute or two but then doesn't move in any gear. I don't have the kickdown cable hooked up and also there is a electrical plug in on the side by where you hook the transmission cooler lines, that isn't hooked up either, what is that for?
Well if anyone has any suggestions for me I would greatly appreciate it! It just doesn't make any sense why it wil go forward and reverse but after a couple of minutes it won't do anything
Thanks,
Todd
Well if anyone has any suggestions for me I would greatly appreciate it! It just doesn't make any sense why it wil go forward and reverse but after a couple of minutes it won't do anything
Thanks,
Todd
#2
What do you mean it won't work? No gears? Slips in all gears? Has reverse only? Has forward gears only? Who is "the guy" who said it worked before? How long did it sit in that other car without running? How did the fluid and valve body look when you pulled it for the shift kit? Are you positive you put the 2 check ***** back in that the Stage 2 kit calls for? It should work but shift early without the detent cable connected and adjusted. Unlike the 700r4, you can run the transmission without the cable and do no harm. The electrical switch you are reffering to near the cooling lines on the passenger side of the case is likley a timing kill switch, used in later 60's and early 70's to kill timing advance except when in 3rd gear. Not 100% its that smog switch but about 99.5%. You should be able to pull the swtich out and plug it.
#3
I can only think of 2 possbly 3 things that will cause your issue. Are you sure you have the filter installed in the transmission? The filter works as your pick up in the pan. And you are positive you have enough fluid? When did you check the fluid? After its good and warm, and in Park right? And you've checked the fluid again after you've ran it through all the gears? Reason I ask those questions is, as said, without a filter you might not be picking up the fluid, if you checked fluid level before you ran it through all gears, or again after you did this, the converter may have primed and took your fluid level to low, or filled up the radiator cooling tank and ran your level low. And check it while warn and running when the the trans is full of fluid and at correct level since level should read high without engine running.
Another issue I think it could be, the transmission sat to long and the seals dried up and got hardened. Reason it works at first, is fluid is thicker when cold. The second it warms and gets thinner then fluid leaking past the seals. If you all of the above is correct, filter installed and level is good, then you have nothing to lose but to try a good transmission conditioner. It may cause the seals to soften and swell then the trans might work again but in most cases is short lived, but it does help you figure out what the problem is.
The possible 3rd thing and I kinda doubt, is the pump gears maybe wore out. Again, thinner fluid will not pump if the gears are badly worn.
#4
My bet is low fluid.
When you drain ALL the fluid out, it takes A LOT of fluid to get it working again, and the last SEVERAL quarts all look like there's almost enough (like, just touching the bottom of the dipstick), but it still keeps taking more. Add more fluid and see what happens.
- Eric
When you drain ALL the fluid out, it takes A LOT of fluid to get it working again, and the last SEVERAL quarts all look like there's almost enough (like, just touching the bottom of the dipstick), but it still keeps taking more. Add more fluid and see what happens.
- Eric
#5
I was hoping so too MD. Thinking he's picking it up out of the pan in the first minute, then runs the pan dry.
On another note, even if you are checking the fluid properly, there are about humpteen 30 different dipstick tube lengths. If someone put the wrong dip stick in the wrong dipstick tube, it might be lying to you. Add another quart to see what happens. If it fixes it, and its working properly, then add one more quart
On another note, even if you are checking the fluid properly, there are about humpteen 30 different dipstick tube lengths. If someone put the wrong dip stick in the wrong dipstick tube, it might be lying to you. Add another quart to see what happens. If it fixes it, and its working properly, then add one more quart
#7
No, I ended up adding 9 1/2 Quarts the shop manual said it held 10 quarts when empty or 20 Pints, it's on full and isn't foamy. Yes I had my car runny for easily 20 minutes, we got it to move in all gears 3 or 4 times, It should have been plenty warm. I'm pretty sure I put the ***** in the right spot, as I recall I had to use only one of the bb's for the street/strip. I did the shift kit last fall and was going to put this in then but then it snowed about a month early here so it sat in the shop all winter. I borrowed my mechanic friends shop and lift and he is baffled too. He said he can rebuild them in his sleep and he has never seen one that worked fine for a couple minutes and then just up and quit all together, I mean you leave it off for 5 minutes and then it will work again for a couple minutes. It had been a long day, he came by after I had put it all in and was having the problems, he said we'll have to take the pan off and see what is going on there, but I was hoping I didn't have to waste all that new tranny fluid to do it, I used the same dipstick that was on the tranny. It had probably not been drove for a few yearsI was hoping someone here had the magical answer for me hahaha
#8
Also I used "Mag" brand premuim Transmission Fluid use where dexron is needed, it is what the parts place sold me for my vehicle, I see in the shift kit instructions that it said to use type F fluid, Is that right?
#11
It starting to sound to me like its a do or die situation. Try adding a trans seal conditioner and see if those seals will soften and swell and correct the issue. If that doesn't work, then I'd say the "the guy" could certianly be wrong about it worked before it was parked. From sitting, the only damage I can think of is seals getting hard. I hate additives of any kind in motor or transmission, but trans conditioner is one additive I have seen revive a transmission several times. Usually in a situaton where a vehicle sat for years.
#12
Isn't there a screen in the valve body? kind of like a little funnel looking thing? If so do you suppose it works fine and then gets somewhat plugged with some junk and then won't let any or enough fluid threw?
#13
I've used Dex 2 on many many Th350 and Th400 with B&M Shift Improver Kits. B7M suggests Type F will give a firmer shift, but Type F doesn't have all the properties that Dex 2 had so I never used Type F. Type F also does not have as much anti foaming agents in it. I'd avoid Type F if it were me. As said, I've had neck breakin, axle breaking 2nd gear shifts with Dex 2.
#14
Allright so today we took the pan and valve body off and the pan was dirty again, I'm assuming it was the fluid from the torque converter or the cooler because I had put in 9 1/2 quarts, it only holds 10 quarts, anyways found a piece of old gasket about 1"X 1 1/2" must have been plugging it somewhat, I guess when I was scraping of the old one some got lodges in there, wierd, Well now it works except it doesn't shift very hard in the 1 to 2 gear any idea's why? It just shifts like a normal transmission 1-2
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