Rebuilt 727 slow to no engage

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my5thmopar

Life Long MOPAR Owner
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This is in my D100-440 project. The trans is 1966 and was rebuilt by shop not, me. The guy I got it from has used the shop before and says they do good work but, who knows. Yes I know, go ahead with the tongue lashing. I should have pulled the pan and checked their work. I added a Lokar kickdown cable and shifter which meant I had to loosen the forward/kickdown band nut. (not the adjuster). It was at 2.5 and I did adjust it per the FSM. The engine has to be revved 3k to get engaged in any gear. Sometimes after it engages, it shifts normal between all P-R-D gears at idle. Note: I have not road tested yet. The TC was used and came with the trans. I believe it is stock and big like 11/12 inch. The fluid level is correct and the dip stick measured with the case. Any quick suggestions before I pull trans or the pan and start looking? Also, what are symptoms of a bad TC? Thanks Craig
 
Buy a large diameter 300 psi pressure gauge, a few 1/8" npt fittings, and some hose. Pressure tests are easy to do with a FSM or one of the books by Munroe or Tom Hand.
 
Summit has a pressure gauge and hose for $69 now and it'll help you diagnose issues like this.
Tom Hand
 
Update. Trans guy says it’s the converter but, I don’t buy that. Read on. Road tested today. Checked fluid and slightly over filled now. Revving heavy, engine in neutral, I hear the pump whining and it engages. I have a 2-3 flare and very delayed KD. I’ve readjusted the KD band and cable. KD at 2 turns and cable probably a little loose. I’m disappointed since this was rebuilt by a ”mopar trans guy” but, something is not right. Suggestions before I order a gage and check pressures? Craig
 
I've never checked trans pressures. But you didn't even check the converter valve did you. Are you sure it's full running in neutral and checking both sides of the stick after wiping it off?
 
I've never checked trans pressures. But you didn't even check the converter valve did you. Are you sure it's full running in neutral and checking both sides of the stick after wiping it off?

Nope haven’t taken it apart. I’ve been working and driving Mopars since the 70s. You have already asked about the fluid 2x. Same answer not low. I’ve rebuilt AT before and it looks like I’ll be tearing this one down too. Was hopeful for a quick fix but, if you want it done right then you have to do it yourself.
 
Try adjusting the bands 1/4 turn less than the FSM perscribes. Ive found it to work better and no further adjustment down the road. My .02

Tim
 
If it doesn't engage into both forward and reverse it's possible something is put together wrong in the valve body. The only problem is you have already revved it to the moon and back trying to get it to engage and that most likely smoked the clutch packs so i'd take it out for a complete inspection. Your only saving grace for the clutches is it could be a broken torque converter. Was this a working trans/converter when sent to the shop for a rebuild? If it was you can most likely rule out the converter
 
If it doesn't engage into both forward and reverse it's possible something is put together wrong in the valve body. The only problem is you have already revved it to the moon and back trying to get it to engage and that most likely smoked the clutch packs so i'd take it out for a complete inspection. Your only saving grace for the clutches is it could be a broken torque converter. Was this a working trans/converter when sent to the shop for a rebuild? If it was you can most likely rule out the converter

Thanks everybody for the help. Update. Although the fluid level is correct, I dumped another quart+ and has over 10 quarts in it now. No change to the issues. After it engages it will shift back and forth through all gears at idle. These trucks have a removal cover and I can clearly hear the pump when it is working. When accelerating normally, the 1-2 is firm (like a TF2 installed but, doesn't have one). The 2-3 flares every time and slips like it was thrown into neutral. Let off the gas and it moves to 3rd and operates normally while in 3rd. KD or quick acceleration causes the same thrown into neutral sound. Fishy, IDK the condition of the TC. If the TC was broken would it exhibit the stated symptoms, make noise, shake etc? Also, doesn't the 66 have a 19 spline TC?
 
Thanks everybody for the help. Update. Although the fluid level is correct, I dumped another quart+ and has over 10 quarts in it now. No change to the issues. After it engages it will shift back and forth through all gears at idle. These trucks have a removal cover and I can clearly hear the pump when it is working. When accelerating normally, the 1-2 is firm (like a TF2 installed but, doesn't have one). The 2-3 flares every time and slips like it was thrown into neutral. Let off the gas and it moves to 3rd and operates normally while in 3rd. KD or quick acceleration causes the same thrown into neutral sound. Fishy, IDK the condition of the TC. If the TC was broken would it exhibit the stated symptoms, make noise, shake etc? Also, doesn't the 66 have a 19 spline TC?
I overlooked you saying it does sometimes move. In that case I doubt it's anything to do with the converter. Yes a 66 is 19 spline. How is reverse? Does it act the same as forward?
 
I overlooked you saying it does sometimes move. In that case I doubt it's anything to do with the converter. Yes a 66 is 19 spline. How is reverse? Does it act the same as forward?

Yes once it engages, I can go F/R and have driven several miles but, has the 2-3 issues. Yes meaning slow to engage.
 
If you have a constant 2 - 3 flare, one of the two steel sealing rings for the reverse/high clutch on the reaction shaft may have been damaged unnoticed while refitting the pump. This is very easily done on an early 727 due to the narrow reverse/high clutch drum bushing which doesn't provide much of a guide while dropping the pump in. A broken sealing ring here would manifest itself by a loud hiss during the air pressure test if one was carried out before installing the valve body.
 
Do you have a good valve body you can put in it? The 2-3 flare could be the adjustment on the Lokar KD cable.

Hopefully you haven't smoked anything.
 
Have u did a pressure test yet? If u can hear the pump TRyING to work u got problems. Low pressure problems. Pump or sealing rings or seals. Kim
 
Have u did a pressure test yet? If u can hear the pump TRyING to work u got problems. Low pressure problems. Pump or sealing rings or seals. Kim

Not yet I’m going to order a gage as suggested.
 
I visited my buddy today. He gave me the 1976 transmission that came with the 440. The combo was from a running driving truck he owns. I'm going to pull the pan and inspect this one. Although returning the 727 wasn't and option at first, my buddy spoke to the builder. He is returning the it to the builder. Thanks for all the help. Craig
 
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