fazool

OK, I'm biting the bullet and going to rebuild my 700R4 (1986) myself. I have the ATSG manual, Transgo SK700-2&3 kit , the corvette servo kit, and the Transgo overhaul kit.

I see from the ATSG manual that some special tools might be needed for getting out the servo, and some others for removing the pump. Question is, are there any alternate methods? I don't have any of these tools, so am looking for recommendations.

Has anyone else tried this and been successful? If so, let me know how it went and what I should watch out for.

thanks

gene

FJK

I'm in the process of doing exactly the same thing. My trans is currently disassembled & in the process of rebuilding the sub-assemblies. Let me just say, you can't effectively work on this trans, taking it down to the bare case with common hand tools. To get around the trans specific tools, you still need specialty tools & also the ability to fabricate some tools. Here is what I used for disassembly.

The sevo can be dis-assembled by having a helper compress it while you remove the snap ring.

For the pump, I used a 2 bar puller & a bearing puller. The pump is not a press fit, just a close clearance installation that has alot of "stichon" to break loose from the case.

There are 2 snap rings in the case. One requires snap ring pliers with very narrow tips & large opening span. I borrowed these, (made by Snap On).

The second snap ring requires that you first compress the clutch pack pressure plate. This required homemade compressor tools. The main section was a large bearing race with 2 bolts welded to it on angles then welded to to a large washer, thereby forming a "Tepee". A threaded rod then ran through this tepee to the back of the case & through a steel plate. By running down the threads of the rod, the clutch pack pressure plate was compressed for snap ring removal. Removal of this snap ring required "hooking it off" with a dental pick. I could not get a straight shot at it with snap ring pliers.

There is also a tricky spring that needs to be released. It only requires a screwdriver, but the technique is what's important. Search for posts in my name where I describe what needs to be done.

Once the trans is apart, that Tepee device is needed again to compress another pressure plate in the input drum.....except you need to make a rectangular press out of angle iron & threaded rod, or a I did, use a small arbor press.

I haven't got into reassembly yet, but I forsee a metal band for aligning the pump sections. Also the sizing tool for the teflon seals are also required, but I have heard my friend wrapped the seals with elcectrical tape over night to size them down.

If you are a young guy who plans on being a gearhead, don't be afraid of buying specialty tools that you will use the rest of your life. The tools I described are specialty tools, not transmission specific tools. Also keep in mind, if you do get out of it, tools are the easiest thing to sell.

Regards, FJK

fazool

Thanks for the advice.

How hard was it to tear down the tranny? How long did it take you?

geneg

Casey Butt

I know this thread is 7 years old, but it turned up in a search and I have to add something here to save anybody who's also considering rebuilding a transmission a lot of frustration and headache. I'm sure others have turned this thread up while searching about rebuilding a 700R4 also.

These are the special tools you'll need to rebuild a 700R4.

GET THE CORRECT RETAINING RING PLIERS and clutch spring compressors. The retaining ring pliers you need for the internals of the transmission are not the typical round-tipped snap ring pliers you typically find at hardware stores. The typical hardware store pliers will be needed for a small snap ring in the pump (if you're changing that valve), but won't work right for the output shaft, input drum, reverse input drum or low reverse retainer.

The correct pliers (external type pliers) you'll need for these retaining rings have flat tops for opening retaining rings that don't have eyelets (holes) in them.

These are the type of snap ring pliers you find at hardware stores. They will work only for the small snap ring in the pump...




These are the type of pliers you need for the retaining rings inside the transmission...






OR alternatively, and perhaps better, these...



If you don't get the types of pliers shown above you will torture yourself trying to get the retaining rings off and on ...and I mean maybe hours of snapping, prying with screwdrivers and scratching everything up trying to get the rings off and on. Do yourself a HUGE favour and get the correct pliers. The ones above are from $30 to $50, but believe me, after hours of struggling with the wrong pliers and screwdrivers you'll gladly pay for the right pliers. You've been warned.


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Casey Butt

The other things I recommend are the proper clutch spring compressors. You'll need either a universal clutch spring compressor, or two specially made for GM transmissions.

You'll need the rear clutch spring compressor (about $35)...




And the input clutch housing clutch spring compressor (about $45)...



Without compressing the input clutch housing clutch springs you cannot replace the 3-4 clutch pack, so this is a must. Depending on how many miles you have on the transmission you may be able to get away with not removing the rear clutch spring piston (there are only a couple of lip seals that are replaced during a rebuild), so you might not absolutely need the rear clutch spring compressor. You can get both of them from Pro-Built Automatics.

You can make do without these compressors if you make the homemade tools described in the post above ...but for some of you that will be harder than just getting the proper spring compressors in the first place. I've done both and chose to stick with the ready-made compressors.

You also may want a lip seal installer tool. You'll need this to get several lip seals in the transmission to seat properly. You can use feeler gauges to do the same thing, but you run the risk of damaging the lip seals. If you're careful the feeler gauges can work, but the lip seal tool is generally only $10-$20.




To replace the bushings (which you must do for a proper rebuild) you'll need to get the proper bushing driver set (but they're over $150) and a set of bushings. Pro-Built and others sell the drivers. You'll also probably need some extra bushings because you'll ruin some when you're first learning to drive bushings properly (you can buy them separately at a few online transmission parts stores such as "Whatever It Takes Transmission"). The bushings are around $20-$30 for a set and a few bucks for single bushings. Bushing driver set...



If you don't feel like throwing down that kind of money for a bushing driver set (that you might only use once) then take your parts to a local transmission shop and have them drive the old bushings out and press in new ones - it shouldn't be too expensive.

You can use basic hand tools, a little imagination, and a few commonly known tricks (like fitting the pump into the case backwards to align it when re-assembling the pump) for the rest of the rebuild.

My advice: GET the PROPER RETAINING RING PLIERS (say $40); get the input clutch housing clutch spring compressor (another $45) and the rest are your call. With shipping that'll run you about $100. Add the lip seal tool and it's a total of $120. The rear clutch spring compressor will take you to about $165, with shipping. Add the bushing drivers and you're up to $330. You may not need all of these things, so add it up yourself. But even if you did get all of these tools, it's still less than the labour costs at a transmission shop. At least now you'll know what you're up against when you get to those points.

If you have a good book or video to go by and the right tools it isn't hard to rebuild this transmission. If you don't have the right pliers and compressor(s) it can be very frustrating.


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Atilla the Fun

I have 3 specialty tools I made myself for doing 700R-4s, but sorry, no pics. So I'd have to say you should be willing to spend what you must for specialty tools when you have difficulty with regular tools.

TKOPerformance

I bought a universal clutch spring compressor at a swap meet in Carlisle for about $30. I used a feeler gauge to work the seal lips in when required. If you use the later scarf cut shaft seals you do not need the sizer and all that BS. I used a single edge razor blade to make sure the two pump halves were aligned correctly. I made two guide pins (bolts with the heads cut off and a slot cut in the shank for a straight bladed screwdriver) to align the pump while installing it. The snap ring pliers are definately needed too. A set of bushing and seal drivers is also handy (look for these at swap meets too they go for around $20-$30, or Harbor Freight has them).

It takes about an hour to tear down a 700R4 into the various sub-assemblies. Then I work through each one of them one at a time to avoid mixing up parts. Make sure everything is clean, clean, clean. No lint, no debris, no dirt.

glock

where do you buy thoes retaining rings pilers from ??????????

Casey Butt

These are the cheapest I know of ...and they work like a charm, grab the rings securely and open them wide. Saves a TON of headaches.

http://scoutparts.com/products/?view...oduct_id=13796

These fit the bill too, but are a little more expensive (though probably also higher quality)...

http://www.aikencolon.com/Special-Re...rs_c_1151.html

There are a few online shops that sell the "Knipex" pliers, so you might be able to get them a bit cheaper than the above link.

11ellswray

iTrader: (1)

alright,so how did the tranny turn out? its been quite a few years and i would like to know as my car hardly has a second gear at all

junkcltr

iTrader: (1)

If the only problem is a slipping second gear and it doesn't have a lot of miles then you might be able to get away with replacing the 2-4 band and drum. It is a cheap way out and you don't have to remove the valve body or rear part of the gear train. I would pull the 2-4 servo first and make sure it just isn't a bad seal and the 2-4 band is fine. Does it slip in 4th also?

To replace the band you would need a 700R4 pump puller, pump gaskets & washers, servo seals, 2-4 band, reverse drum (ebay good used $30). I would also put in the 3-4 clutches while you are there.
It takes about an hour of removing the servo, pump, band, and then re-assembling.

11ellswray

iTrader: (1)

no only in 2nd, maybe? when i think about it i cant hit the gas that hard in 4 but i thought that was becasue it was downshifting but maybe not? would it help to know that when it went out i was mid powerslide?