K5 Blazer Forums  
Home of the 1969-91 K5 Blazer/Jimmy including GM Trucks and Suburbans.  
Go Back   CK5 Forums > Technical Discussion > 73-91 K5/Suburban/Truck

Remove these ads.

Reply
 
Thread Tools Display Modes
Old 04-22-2010, 07:28 PM   #1
trmn8r
Registered User
 
Join Date: Sep 2009
Location: Amarillo, TX
Posts: 9

i Trader: (0 )

Question TH350 not shifting to third

Getting my '78 blazer running again after it sat for about 12 years.

Everything is working pretty good with the exception of the transmission.

Basics of what I got. 383, TH350, NP205. TH350 has a B&M shift kit installed in it a long time ago, by myself.

When I parked it long ago it was shifting fine. Shifts hard between first and second... harder than I remember it shifting even after putting the B&M kit in, but maybe I just don't remember right. Checked fluid before ever trying to move it after getting the motor running again, it was low, has a leak somewhere. Think I topped it off with Chrysler tranny fluid, it was all I had setting around. (maybe that's the entire issue? doubt it.) Shifter is going into drive not second, one click above where I'm running it is neutral, so confident my shifter isn't causing it by going straight to second. Checked vacuum line running down to shift solenoid, it's hooked up (have had it come loose years ago when I used this as a daily driver and as I remember that kept it from going into second... seems like it made the first to second shift either slip or very hard, can't really remember).

Basically that's it, any ideas what my next check ought to be? what to look for?
trmn8r is offline   Reply With Quote
Sponsored Links



Remove these ads.
Old 04-23-2010, 05:05 AM
Posted in reply to trmn8r's post "TH350 not shifting to third"
  #2
Greg Ducato
Supporting Member
Registered User
 
Join Date: Mar 2010
Location: Weatherford Texas
Posts: 1,527

i Trader: (2 )

If the vac line is hooked up at both the modulator and the manifold (direct vacuum, not ported) and you are getting a good 15 inches or more of vacuum at the modulator that should be all it requires. Sitting for a while, the line could have a crack in the rubber connections or the modulator diaphram could have a hole in it. Pull the line at the modulator when you check for vacuum and be sure no fluid runs out of the line or modulator nipple. If all is well in that system, move to the kickdown cable. Check to be sure the cable is not too tight or is not bound up and is adjusted so that it is only fully extended at wide open throttle. When you pull it , the cable should snap back to position. If not, the internal kickdown valve could be hung or the spring broken. Third, you can remove the round governor cover from the rear of the trans by carefully tapping around the edge with a blunt chisel or screwdriver. Remove the governor and check to be sure the valve that runs through the center of it is moving frelly when you compress the governor weights. Also check the condition of the gear for damage.
Greg Ducato is offline   Reply With Quote
Old 04-23-2010, 06:05 PM
Posted in reply to Greg Ducato's post starting "If the vac line is hooked up at both..."
  #3
trmn8r
Registered User
 
Join Date: Sep 2009
Location: Amarillo, TX
Posts: 9

i Trader: (0 )

ok, modulator had no fluid running out, went ahead and pulled it out, seems to hold a vacuum on both sides of it, guess it's supposed to. kickdown cable is not tight, it will kick it into first at about 15 or 20 in second, floor it, it kicks down to first. Next is to pull the governor, cleaned around it (my tranny is covered in crud) cant figure out how to get it out. Thought there was a inside snap ring, you pushed in on the governor a bit, popped snap ring out then tapped around on governor to get it to pop out... but cant find an end of what I thought was an inside snap ring...soooo maybe I'm all wrong about that... off to look for instructions somewhere.
trmn8r is offline   Reply With Quote
Old 04-23-2010, 06:16 PM
Posted in reply to trmn8r's post starting "ok, modulator had no fluid running out,..."
  #4
sweetk30
Supporting Member
web wheelin for now
 
sweetk30's Avatar
 
Join Date: Nov 2004
Location: 14845 zip code
Posts: 22,496

i Trader: (57 )

pull off snap on cover ring. then pry out the cover its a slight press fit.

then pull gov.
__________________

2wd resto mod 5.3/4l60e powered : http://coloradok5.com/forums/showthread.php?t=296680
stubby j.r. : http://coloradok5.com/forums/showthread.php?t=309865
project stubby crew cab : http://coloradok5.com/forums/showthread.php?t=245582
diy4x custom dash : http://coloradok5.com/forums/showthread.php?t=284383
snap-on tool box : http://coloradok5.com/forums/showthread.php?t=225524
. . .WHEN I WAN'T YOUR OPINION I WILL REMOVE THE DUCT TAPE ! ! !
sweetk30 is offline   Reply With Quote
Old 04-23-2010, 06:34 PM
Posted in reply to sweetk30's post starting "pull off snap on cover ring. then pry..."
  #5
trmn8r
Registered User
 
Join Date: Sep 2009
Location: Amarillo, TX
Posts: 9

i Trader: (0 )

read somewhere there was a snap type latch similar to master cylinder cover... if thats what you mean by snap off cover ring then mine's different.

and I'll be dang if I can find ends of an internal snap ring like I thought was there.

I'll have to try tomorrow when I can have better light than I had this evening.
trmn8r is offline   Reply With Quote
Old 04-23-2010, 07:05 PM
Posted in reply to trmn8r's post starting "read somewhere there was a snap type..."
  #6
sweetk30
Supporting Member
web wheelin for now
 
sweetk30's Avatar
 
Join Date: Nov 2004
Location: 14845 zip code
Posts: 22,496

i Trader: (57 )

some have ring some dont. anyway press fit tap it out.
__________________

2wd resto mod 5.3/4l60e powered : http://coloradok5.com/forums/showthread.php?t=296680
stubby j.r. : http://coloradok5.com/forums/showthread.php?t=309865
project stubby crew cab : http://coloradok5.com/forums/showthread.php?t=245582
diy4x custom dash : http://coloradok5.com/forums/showthread.php?t=284383
snap-on tool box : http://coloradok5.com/forums/showthread.php?t=225524
. . .WHEN I WAN'T YOUR OPINION I WILL REMOVE THE DUCT TAPE ! ! !
sweetk30 is offline   Reply With Quote
Old 04-23-2010, 08:36 PM
Posted in reply to sweetk30's post starting "some have ring some dont. anyway press..."
  #7
trmn8r
Registered User
 
Join Date: Sep 2009
Location: Amarillo, TX
Posts: 9

i Trader: (0 )

brother in law came over and logged on to his alldata account from his work has diagrams yada yada, now I'm not so sure I wasn't trying to take off the wrong cover COMPLETELY... I was on the passenger side, should have been on the driver side... I was trying to get into second gear servo or something.... frustrated, couldn't find my chiltons when I was over working on it... it'll go better tomorrow I'm sure.
trmn8r is offline   Reply With Quote
Old 04-24-2010, 09:55 AM
Posted in reply to trmn8r's post starting "brother in law came over and logged on..."
  #8
trmn8r
Registered User
 
Join Date: Sep 2009
Location: Amarillo, TX
Posts: 9

i Trader: (0 )

pulled governor, looks fine to me nothing sticky etc... nylon gear engaging and looks good. put it back in, dropped valve body.. ugghh been a long time since I put the B&M shift kit in, forgot what a pain that was gonna be... messy... only have one ball I can locate on plate above valve body. thought there were 2 or 3... off to B&M's web sight to try and find out for sure.
trmn8r is offline   Reply With Quote
Old 04-24-2010, 02:48 PM
Posted in reply to trmn8r's post starting "pulled governor, looks fine to me..."
  #9
trmn8r
Registered User
 
Join Date: Sep 2009
Location: Amarillo, TX
Posts: 9

i Trader: (0 )

couldn't find anyone open on a saturday that has valve body gaskets... guess it's gonna have to wait for monday. buttoned the bottom of the tranny up with a couple of bolts in the pan to keep the 50 MPH wind from blowing dust into the tranny till then.
trmn8r is offline   Reply With Quote
Old 04-25-2010, 06:14 AM
Posted in reply to trmn8r's post starting "couldn't find anyone open on a saturday..."
  #10
Greg Ducato
Supporting Member
Registered User
 
Join Date: Mar 2010
Location: Weatherford Texas
Posts: 1,527

i Trader: (2 )

You only need one check ball, it will go in the transmission side just above the modulator valve line-up. Hope it works out for you.
Greg Ducato is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -7. The time now is 09:47 AM.


Powered by vBulletin® Version 3.8.1
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.