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TH350 Rebuildable?

  
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TH350 Rebuildable?

 
primedexamples primedexamples
New User | Posts: 4 | Joined: 01/13
Posted: 01/25/13
10:38 PM

Howdy yall. I'm running a 77' Byrd with a sbc 350, and TH350 that hesitates when cold, seals causing it to do so? It also leaks a bit and made a bit of a whining noise last week till i put a bottle of fluid in it, Yea... should have checked it more.. I would like to try to rebuild it myself with that b&m trans kit. my question is being a newbie what should I be cautious about? is it possible that I have messed up the internals by letting it get that low? Any help or tips would be much appreciated.

one more thing, occasionally it will idle real high. I don't have a tach so i don't know what kinda rpms its doing, stupid esprit gauge cluster, almost like the throttle is stuck, is it possible that the kick down cable gets seized and keeps the throttle from returning down? i have the pcv? line running across the return spring but haven't had trouble the 2 years its been like that untill now.
thanks.  
"its got a pick up motor thats mighty souped up, and that Esprit body makes it look like a pup. Got 8 cylinders and uses them all, doesn't have overdrive and needs a stall. 4 barrel  carb and dual exhaust, those highway gears need to really get lost. aint got safty tubes cause i aint skeerd. tire are good brakes are fair" - 'HotRod Pontiac' by The Primed Examples

68scott385 68scott385
Enthusiast | Posts: 669 | Joined: 05/09
Posted: 01/25/13
10:53 PM

Does it have a 2bbl carb or 4bbl carb? Is it a Rochester carb?

The trans: it's whining is caused by the pump running with less fluid than it needs. Running it like that will caused pump damage. It is fairly easy to disassemble a th350 trans IF you have the right tools. Without the right tools you're asking for headaches. You COULD buy the tools to do it yourself but the for the price of the tools you could have a reputable trans shop build it AND have a warranty.

If you decide to do it yourself, buy a book, read it twice, then go for it.

GOOD LUCK  
68scott385 68scott385 68scott385

primedexamples primedexamples
New User | Posts: 4 | Joined: 01/13
Posted: 01/26/13
03:39 PM

may bad for the two posts. Its a four barrel Edelbrock performer.

I'm not above having some one doing it, but idk if i can drop the 1500 to have it rebuilt. i know if i did do it myself i need a slide hammer to remove the pump bolts correct? and a spring compressor, some c clamps, and someone to machine the direct clutch piston machined to fit the extra clutch. Also planned on picking up the "TH350 Handbook." i have the slider hammer, and some large c clamps, what else would i need?

Thanks for the help  
"its got a pick up motor thats mighty souped up, and that Esprit body makes it look like a pup. Got 8 cylinders and uses them all, doesn't have overdrive and needs a stall. 4 barrel  carb and dual exhaust, those highway gears need to really get lost. aint got safty tubes cause i aint skeerd. tire are good brakes are fair" - 'HotRod Pontiac' by The Primed Examples

68scott385 68scott385
Enthusiast | Posts: 669 | Joined: 05/09
Posted: 01/27/13
09:48 AM

You need a puller to get the pump out without damaging it. You could probably use a slide hammer if you had the right fixture for the end but you'd have to use gentel pressure, not large bursts. The bolts that hold the pump are regular bolts, unscrew them and they come out.

You'd have to have a spring compressor for the low/reverse clutch piston. There is also a tool needed to compress the 1-2 accumulator spring so you can remove the snap ring to pull the 1-2 accumulator cover out. You have to get the pump halves in perfect alignment to reinstall them into the case, there is a tool for that, too. There are a couple teflon o-rings that have to be gently expanded then recompressed onto the input shaft, that takes a special tool and there ain't no getting around that part, it has to be done right or you'll be taking it apart repeatedly.

Buy the book first, read it, understand it, them decide whether or not you can do it yourself. Fifteen hundred (that's not a bad price) is hard to part with but it also comes with a warranty.  
68scott385 68scott385 68scott385

68scott385 68scott385
Enthusiast | Posts: 669 | Joined: 05/09
Posted: 01/27/13
09:59 AM

As for your stumbling problems, you're going to have to tune the carb. Have you made any changes to it from when it came out of the box?

You can start by making sure the the accelerator pump rod is adjusted to ivet the largest pump shot. Then changing to a higher number step-up spring, the factory setting is 5inhg, you can go to 7inhg or 8inhg. Then start by increasing the squirter size.  
68scott385 68scott385 68scott385

redneckjoe69 redneckjoe69
Enthusiast | Posts: 388 | Joined: 04/10
Posted: 01/27/13
02:51 PM

Icon Quoteprimedexamples:
may bad for the two posts. Its a four barrel Edelbrock performer.

I'm not above having some one doing it, but idk if i can drop the 1500 to have it rebuilt. i know if i did do it myself i need a slide hammer to remove the pump bolts correct? and a spring compressor, some c clamps, and someone to machine the direct clutch piston machined to fit the extra clutch. Also planned on picking up the "TH350 Handbook." i have the slider hammer, and some large c clamps, what else would i need?

Thanks for the help


$1,500 seems like an aweful lot to rebuild a th350.

   you can buy one through jegs or summit for under a grand.   i think summit sells one for around 750?   id shop around or call some different rebuilders in your area.    and as stated, you would have a warranty at least.    just my 2 cents.  

pepsi1 pepsi1
Enthusiast | Posts: 301 | Joined: 10/11
Posted: 01/28/13
03:47 AM

Welcome primedexamples:

If it only does it when it's cold then its a oil flow problem.

CHANGE THE OIL AND FILTER FIRST.....

1.Drop the pan, and replace the oil, and filter. If it gets better, then run it 100-200 miles and drop the oil and replce the filter again.
  NOTE: Check the Torque convertor. On some older convertors, they did install a small drain plug.

2.If that helps, when it get warmer. Install a Seperate trans oil cooler.

Those are not typo's 100-200 Miles. It's the cheapest thing you can do.

3.If the oil/and oli filter change doesn't help. Get it to a trans shop.

Bob  

primedexamples primedexamples
New User | Posts: 4 | Joined: 01/13
Posted: 01/29/13
01:40 AM

Its a used carb, idk how old. Is the tuning your talking about involve tearing into the carb. Only adjustments i know of are the air/fuel on the front, that and the idle adjusting screw. Yall kindly have scared me away form the rebuild though I think I'm gonna pick up the Th350 guide book and take your advice however on seeing how i feel about it afterwards, meantime i reckon I'm gonna try the filter trick and see how she does. Pepsi what would i gain by running an extra trans cooler other then I'm assuming a cooler running temp? or maybe a cooler trans temp is more important than i think it is? Do i need/would it be best to drain the converter if it does not have a plug?  
"its got a pick up motor thats mighty souped up, and that Esprit body makes it look like a pup. Got 8 cylinders and uses them all, doesn't have overdrive and needs a stall. 4 barrel  carb and dual exhaust, those highway gears need to really get lost. aint got safty tubes cause i aint skeerd. tire are good brakes are fair" - 'HotRod Pontiac' by The Primed Examples

68scott385 68scott385
Enthusiast | Posts: 669 | Joined: 05/09
Posted: 01/29/13
09:28 AM

http://www.edelbrock.com/automotive_new/mc/carbs_acc/pdf/carb_owners_manual.pdf

Here's a link to the Edelbrock carburetor owner's manual. For the adjustments I was referencing you will have to take the top off the carb, maybe several times before it's fine tuned to your specific application. It's the easiest carb to work on ever made. They don't have as many adjustments or adjustable features as a Holley but they can be used effectively with some tinkering.  
68scott385 68scott385 68scott385

68scott385 68scott385
Enthusiast | Posts: 669 | Joined: 05/09
Posted: 01/29/13
09:54 AM

This link is to TCI's tech section and shows transmission life expectancy vs. transmission fluid operating temperature.

http://www.tciauto.com/tc/trans-life-expectancy

Here is a series of links to YouTube, they show the disassemble, inspection, & reassembly of a th350 transmission. After watching you will be able to decide whether to do it yourself or take it to a shop. But keep in mind that the guy(s) in the video have done this many times and have the proper tools.

http://www.youtube.com/watch?v=DrPF05kS154&list=UU2uy7T-3yXxLUVjroyyOR7A&index=7

http://www.youtube.com/watch?v=GzZwdzbZaqg&list=UU2uy7T-3yXxLUVjroyyOR7A

http://www.youtube.com/watch?v=tjiIo48vWyc&list=UU2uy7T-3yXxLUVjroyyOR7A

http://www.youtube.com/watch?v=0P7j0lUaSDg&list=UU2uy7T-3yXxLUVjroyyOR7A  
68scott385 68scott385 68scott385