The Diesel Garage banner

3406B high idle adjustment ????

23K views 6 replies 4 participants last post by  Log truck driver 
#1 ·
hi all first post :) i recently acquired a rolled 1988 international 9370 with a 3406B (1100 miles on inframe), 7 speed eaton, 3:90 rears, 11r22.5 tires

well after days of work changing the cabs over and putting some new rubber on the front i took her out for a test drive and when the govenor maxed out at 1700 rpm i was only doing about 57 mph

i figured if i could get another 300 rpm i might get a top speed of 67 or so?

how hard is it to adjust the high idle on a 3406B?

i got some hay to haul next week about 350miles north and the 57mph would drive me nuts on the interstate :)

any help would be greatly appreciated
 
#3 ·
Welcome!
Looks like you got the 'Binder rollin good...except the 57mph part. I'm not experienced in the 3406's enuf to give pointers, except the fuel rate adjustment is in my signature. I think Ynot said these can go to 2300rpm. Hopefully he'll see this.
 
#4 ·
Yep, 2300's real safe. High idle is under the oval shaped cover just to the inside of the shutoff solenoid. One 1/4" bolt holds it on. 1/2" jam nut on a flathead screw. Turn it out 6 turns and check the high idle on a good tach. Cat never made a 1700 engine, so I wonder if you have something wrong (like a bad tach and 4.11 gears or something). Welcome aboard and good luck bud!!...T
 
#5 ·
well, this is embarising, there was a bolt threaded up threw the floor under the pedal that the previous owner installed for a throttle stop :oops: now she'll do about 75mph at 2200rpm

at leaste it was an easy fix :)

you got some neat ideas ther nevrenufhp, how much harder is it on the ole 3406 crankin her up like that?
 
#6 ·
You'd need to monitor exhaust temps to know when too much is too much. It may damper your fuel economy if you drive it hard too. The 3406 is extremely durable.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top