727 slipping

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Hadahemi

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OK, started up the Demon today, got the engine running great, and the trans too...I thought. My combo is a fairly fresh but stock 440 with a new rebuilt 727 lockup trans. Its the first time the trans has been used since the rebuild, and I had Frank Lupo make me a 11inch 2400 stall converter for it (and yes its a lockup style converter). At first, the trans did great, then after it got warmed up on the maiden voyage it slowly kept slipping more and more until the revs had to be rediculously high just to get it to move. Trans fluid level is good...checked it with engine running and trans in neutral. Initial adjustment of the kickdown linkage was checked 3 times, although when I got back from the short drive,I checked it again and did have to adjust it some. The adjustment made no difference though, I can put it into gear now and there is no trans pull at least at idle. What am I missing? Is there any thing else that may need adjusted? Is the kickdown supposed to have a spring to keep it pulled forward at the carburator, or does it just rely on trans spring pressure for the forward movement, could that be the problem? Any ideas, please speak up. Thanks
 
Bummer, Frank built my trans and gives a 1 year unconditional guarantee no matter what the problems or how its used.
 
LOL, I'm REALLY hoping the thing isn't toast, I see now how the spring is attached from some pics I found. Maybe thats all the problem is???
 
The throttle pressure linkage (kickdown linkage) (spring included) will not affect it at all. You could remove the throttle pressure linkage all together and the transmission would still take off just fine. The throttle pressure linkage varies clutch pack pressure and affects the shift timing. Sorry to say but it sounds like the rebuilder either folded a seal over backwards or nicked it in a clutch pack or possibly didn't check the clutch pack clearance and it had way too much. Could also be a valve body problem but it sounds more like a clutch pack issue. Call Frank on Monday. He's a good guy and will take care of it I'd bet.

Just noticed you said a local rebuilt it. He's who you need to talk to, not Frank.
 
An update...a check revealed that the trans portion of my radiator is plugged, it allowed very little if any fluid to pass through. New opionions?? Did I just fry the trans due to heat buidup? Or still thinkin internal mechanical flaw??Let me know what you think.
 
A plugged up cooler will cause the trans. to overheat but if you only drove it a few miles I highly doubt that's what caused your problem. Still sounds to me like they screwed up something when rebuilding it. I'm sure the plugged up cooler didn't help though.
 
This just dawned on me. Let's suppose the cooler was packed full of crud from the last time the trans. burned up. You now put in a new trans. and the pressure forces all that crap into the new trans. and plugs up the filter so it can't pump anything. I'd drop the pan and have a look at things.

Also let there be a lesson learned here. Any time you pull out a burned up trans. flush the trans. cooler thoroughly.
 
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