700R4 Gurus ?

[cwn anwyn]

OK here is my dilema. I am swapping in my spare 700r4 that I pulled from my parts Blazer (84). My torque converters that I had in the garage do not match up to it. 27 splines vs 30 splines. Also, I am not 100% sure that junk didnt get in them. Same goes for the TC that came out of the spare trans. I buy one from the parts store and it ends up being an early 84 27 spline TC(PN GM15) . I get that swapped out for an 84.5 30 spline (GM18A) and now I run into my problem. I get the trans mated to the engine and the torque converter has about 1/4 inch space between the flexplate and the holes for the bolts. The converter is fully engaged on the trans, just not meeting up with the flex plate. What torque converter do I actually need. I dont really feel like dropping the transmission multiple times to figure it out. Any info would be greatly appreciated.

Z

 

[JNygard]

That gap is normal, just pull converter out and bolt to flex plate.

 

[K5er4Life]

Sure is, there is always a little bit of space between the flexplate and torque converter. 1/4 inch sounds just right.

 

[nemesis_pyros]

Yup pull 'er forward, bolt it up and git 'er done.


Hey wheres my lift?

 

[1985_K5_Silverado]

Now, to answer a question that wasn't asked, that small amount of endplay must exist to make sure that the converter doesn't exert a bunch of axial pressure on the crankshaft (because that would put pressure on the the crank thrust bearing and wear the crap out of it). The clearance you're seeing allows for converter expansion due to heat. I think 1/16 is the absolute minimum (but that's playing with trouble), 1/8 is preferred, and 3/16 is the maximum allowable. It sounds like you're in the ballpark.

 

[cwn anwyn]

Hey thanks for the quick answers. I had thought it a little odd since my old trans(orig) and the junkyard one I swapped in both had the converter almost right up against the flexplate. This one caught me a little off guard.

Nemesis, the lift should be boxed up and ready to go this weekend. I got most of it off right now. I'll finish pulling it hopefully tonight or tomorrw evening. I think I might try to skate out of work a little early today so I can finish it up. Thanks,

Z