jetaway won't down shift

Thread Tools
 
Search this Thread
 
Old July 20th, 2021, 08:48 PM
  #1  
Registered User
Thread Starter
 
Cutlass Fan's Avatar
 
Join Date: May 2016
Location: Saskatchewan
Posts: 534
jetaway won't down shift

I have a 65 Cutlass 330 4bll with the Jetaway trans and 3.23 rear axle. When floored from a stop it ***** hard into high at about 45 mph. If held in low it hits 65 at about 5000 rpm . Also it won't kick down when floored. The switch pitch seems to be working properly. I would like to shift into hi at 4500 to 5000 rpm at wot and have it kick down when floored below 55 mph or so. What do I check
Cutlass Fan is offline  
Old July 21st, 2021, 04:37 AM
  #2  
Registered User
 
JohnnyBs68S's Avatar
 
Join Date: Jun 2014
Location: Ft. Wayne, IN
Posts: 1,223
Sounds like the kickdown switch isn't working. On my '68 (non switch pitch Jetaway), if I held the pedal to the floor hard enough to engage the downshift switch, it'd wind out until 70 MPH before it shifted (2.78 rear gear). If I floored it but didn't engage the switch, it would shift at around 55-60 MPH (didn't have a tach back then). Any time I stomped it (engaging the switch) when going less than ~65 MPH, it would downshift.
JohnnyBs68S is offline  
Old July 21st, 2021, 09:18 AM
  #3  
Registered User
 
Jeff Stout's Avatar
 
Join Date: Jan 2021
Posts: 190
Mine was a vacuum line.
Jeff Stout is offline  
Old July 21st, 2021, 09:56 AM
  #4  
Administrator
 
oldcutlass's Avatar
 
Join Date: Oct 2009
Location: Poteau, Ok
Posts: 40,728
First check and make sure you have 12v at the transmission tab when the pedal is floored. If you don't like the shift points you'll need to modify the weights on the transmission governor.
oldcutlass is online now  
Old July 21st, 2021, 10:50 AM
  #5  
Registered User
 
Koda's Avatar
 
Join Date: Aug 2013
Location: Evansville, IN
Posts: 10,455
Originally Posted by Cutlass Fan
I have a 65 Cutlass 330 4bll with the Jetaway trans and 3.23 rear axle. When floored from a stop it ***** hard into high at about 45 mph. If held in low it hits 65 at about 5000 rpm . Also it won't kick down when floored. The switch pitch seems to be working properly. I would like to shift into hi at 4500 to 5000 rpm at wot and have it kick down when floored below 55 mph or so. What do I check
If it shifts into high at 45 hard, it won't kick down into into first when you floor it at anything above that speed because you are already too fast for that low gear. Go see if it will kick down after it shifts to high at 30 or so.

If you want to change the shift points, that's not the kickdown switch.
Koda is offline  
Old July 23rd, 2021, 04:24 PM
  #6  
Registered User
Thread Starter
 
Cutlass Fan's Avatar
 
Join Date: May 2016
Location: Saskatchewan
Posts: 534
As I remember my 66 f85 acted the same as Johnny B's. Eric is the trans tab you refer to on the throttle switch on the firewall?
I wouldn't think it should be "too fast" when you can manually hold it in low until 65 which is 5000 rpm.
It shifts down into low below 15 to 20 mph under moderate acceleration.
Cutlass Fan is offline  
Old July 23rd, 2021, 09:10 PM
  #7  
Administrator
 
oldcutlass's Avatar
 
Join Date: Oct 2009
Location: Poteau, Ok
Posts: 40,728
Originally Posted by Cutlass Fan
As I remember my 66 f85 acted the same as Johnny B's. Eric is the trans tab you refer to on the throttle switch on the firewall?
I wouldn't think it should be "too fast" when you can manually hold it in low until 65 which is 5000 rpm.
It shifts down into low below 15 to 20 mph under moderate acceleration.
Yes, but the one I'm talking about is where that wire connects at the transmission.
oldcutlass is online now  
Old July 26th, 2021, 04:19 PM
  #8  
Registered User
Thread Starter
 
Cutlass Fan's Avatar
 
Join Date: May 2016
Location: Saskatchewan
Posts: 534
Thx Eric I'll check that out.
Cutlass Fan is offline  
Old July 27th, 2021, 08:39 AM
  #9  
Registered User
 
JohnnyBs68S's Avatar
 
Join Date: Jun 2014
Location: Ft. Wayne, IN
Posts: 1,223
Originally Posted by Jeff Stout
Mine was a vacuum line.
I'm pretty sure the vacuum modulator on the Jetaway controls only the partial-throttle upshift point. Once it shifts to 2nd gear, the only way to get it to downshift is to stomp it hard enough to engage the downshift switch or pull the shifter back to "L" (at least that's how mine worked). Pushing the pedal to the floor without engaging the downshift switch would not cause it to downshift even if it was going only ~20 MPH in 2nd. Another peculiar behavior was that if I floored it from a stop w/ the shifter in "L" without engaging the downshift switch, if I moved the shifter from "L" to "D" it would force an upshift even if going only around 30 MPH (long before it would've naturally up-shifted if started in "D"). It was like the shift from "L" to "D" over-rode the vacuum modulator's natural upshift point. However, if I engaged the downshift switch, moving from "L" to "D" did nothing and it up-shifted at ~70 MPH as usual.
JohnnyBs68S is offline  
Old May 24th, 2022, 08:42 PM
  #10  
Registered User
Thread Starter
 
Cutlass Fan's Avatar
 
Join Date: May 2016
Location: Saskatchewan
Posts: 534
Sorry for not posting an update sooner. I hate it when an OP doesn't fallow up after asking a question.
Anyways I didn't get around to doing anything the about it until this spring. I ended up taking the kick down switch apart and discovered that the terminals were corroded. I cleaned them and took it for a drive. Success! Not only does it kick down but holds passing gear to slightly over 70 mph (5500 rpm) instead of the previous 45 mph. So obviously its not just the governor that controls when it up shifts.
Thanks for the help.
Cutlass Fan is offline  
Old May 25th, 2022, 08:08 AM
  #11  
Registered User
 
JohnnyBs68S's Avatar
 
Join Date: Jun 2014
Location: Ft. Wayne, IN
Posts: 1,223
Thanks for the follow-up, glad you got it working correctly.
JohnnyBs68S is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
August442
442
3
March 21st, 2020 01:41 PM
stevengerard
Electrical
14
September 10th, 2014 03:17 PM
Texas442
Electrical
3
March 28th, 2013 07:13 PM
MN71W30
Transmission
14
January 25th, 2013 06:43 AM
Dpc2
Electrical
11
October 17th, 2012 12:23 PM



Quick Reply: jetaway won't down shift



All times are GMT -7. The time now is 02:03 PM.