The 3406 fuel screws "spring" method - Diesel Truck Forum - TheDieselGarage.com
Thread Details Posted by nevrenufhp, this thread has received 3 replies and been viewed 23493 times.

 
LinkBack Thread Tools Display Modes
post #1 of 4 (permalink) Old 12-16-2006, 05:43 PM Thread Starter
Super Moderator
 
nevrenufhp's Avatar
 
Join Date: May 2005
Location: Sacramento
Posts: 3,187
Points: 103,987
Thanks: 259
Thanked 236 Times in 181 Posts
The 3406 fuel screws "spring" method

Take the line and 2) 1/4" bolt cover off the air fuel ratio on the very back and top of the gov. Nothing there to be scared of. Grab the plunger stem with plyers and break the 7/16" jam nut loose with box end wrench, Turn screw all the way in until just leaving enough threads to lock down. Not real precision, just set it anywhere tight. Re-assemble... On the very bottom of the rear of the gov. towards the outside (frame side) is another 1" tall 1/4" bolt cover. Remove the bolts, one on top of the other this time, and smack down on the cover with a screwdriver and hammer. The harder the better. It'll leave the gasket perfectly intact for reassembly that way. Again, nothin to screw up so have at it. Facing in from the back stick your pinky in the slotted hole and push in on that thing. Just face the front of the truck, turn palm up and stick it in. Again, and just to clarify, this is all idiot proof and you can't mess anything up on any of this. Ain't rocket science, for real. Easiest motor to jack up, for sure. SSSooooo, you'll feel the rack screw bar with the fuel and torque screws. Just push on whatever you run into in there. The more travel, the more servo movement. All you're doing with your finger is makin sure another bonehead wasn't in the playin. Make sure when you push it all the way in (about 5/16" travel plus change is about 425hp stock, but doesn't really matter how fat it does go) you can feel about .030" or so (just picture a .030" gauge and guess, really) of secondary spring pressure. That is the torque spring on the stop bar. It doesn't have to be exactly anything, just want that little bit of extra pressure for torque rise. I won't explain it all, but your feeling torque spring pressure from the screw making sure someone before didn't turn one screw out from the other (doing it wrong). There are two screws side by side. If there is no pressure there, turn the outer most screw (towards you) in until there is. Do this with a 1/4" drive 3/8" deep socket (12 point is easier) with baby vice grips clamped to the very end as the lever and a sumthin stupid like 7/64" or somethin allen wrench down the center. Just take your allen set and stick it in the end of the screw to find the size (or call your local dealer, ask for truck shop and just ask em what size). Insert socket, break loose counter clockwise with allen wrench in hole, turn screw and lock back down. If your torque pressure feels OK, or you reset it as stated, back out both screws evenly to the tune of about 20hp per turn or so. Wipe off housing and cover and stick back on with original gasket. No glues on anything anywhere here. If the trucks in good shape, go 3 turns or so and run it a round. If your pyro stays below 950, meaning it's timed close enough to stock or advanced properly, turn it out another 3 and call her good. That's it. Have fun. It can be super tweaked with meter timing and gov. removal, but you'll be pretty happy like this unless you run into me on the road somewhere. Want peace of mind and better mileage, take it to someone trustworthy (Cat dealer, and tellem you want an old timer on it) and set a tight overhead ($225 or so) and meter time ($100) to (for your 92) 17.5 degrees at 1000 and start at 1230, plus remove the stop screw and toss it. This won't make sense to you but that's exactly what you tell him. He'll know just what you're saying, believe me. That'll land you between 5.2 and 5.7mpg depending on what you haul, and between 530 and 560 hp. You'll know it all worked when it goes from 20psi boost to 27 the first time (3 turns) and 32+ the next (3 turns). Add an 0R6051 turbo for a couple more pounds and better power ($1000 with your core as an even swap, and don't let them try to tell you there's a core charge. There isn't, for sure). And don't worry, it'll all take it just fine. With more exagurated tuning, she'd pull 800hp just as it sits with no motor mods whatsoever and live to 750,000 miles without a hitch. If you're running 15psi boost right now and the first 3 turns didn't increase the boost, have the dealer replace you air fuel ratio diaphram ($100). Have fun...

Thanks again Tony!
Attached Thumbnails
Click image for larger version

Name:	3406 AFC.jpg
Views:	1852
Size:	269.1 KB
ID:	30713   Click image for larger version

Name:	3406 fuel screw cover.jpg
Views:	3301
Size:	275.7 KB
ID:	30721  

Dale

my daily driver:67 F100, 300 4V, cammed, 4 spd.
or, 08 Subaloser Forester, 2" lift.
work rigs: 94 IH 4900, DT466(originally 230hp), #0 fuel plate, tighter gov springs, 22* timing
or, 06 IH 7400, DT466E, 300hp


My Low Buck fuel rate site:
www.freewebs.com/nevrenufhp

Last edited by nevrenufhp; 02-02-2013 at 03:49 PM.
nevrenufhp is offline  
The Following 2 Users Say Thank You to nevrenufhp For this addition to TDG:
122 cat (05-20-2010), jdub63 (09-09-2014)
Sponsored Links
Advertisement
 
post #2 of 4 (permalink) Old 01-28-2009, 02:02 AM
The other guy
 
Join Date: Jan 2007
Location: Brenham, Texas
Posts: 3,936
Points: 105,540
Thanks: 36
Thanked 1,350 Times in 846 Posts
Quote:
Originally Posted by nevrenufhp View Post
Thanks again Tony!

________________________________________
Boredom leads to a spellchecked, more legible re-write: Hope this helps. I remember the first response before Nevr taught me what a paragraph was ;-)

>Take the line and 2) 1/4" bolt cover off the air fuel ratio on the very back and top of the gov. Nothing there to be scared of. Grab the plunger stem with pliers and break the 7/16" jam nut loose with box end wrench, Turn screw all the way in until just leaving enough threads to lock down. Not real precision, just set it anywhere tight. Re-assemble...

On the very bottom of the rear of the gov. towards the outside (frame side) is another 1" tall 1/4" bolt cover. Remove the bolts, one on top of the other this time, and smack down on the cover with a screwdriver and hammer. The harder the better. It'll leave the gasket perfectly intact for reassembly that way. Again, nothin to screw up so have at it. Facing in from the back stick your pinky in the slotted hole and push in on that thing. Just face the front of the truck, turn palm up and stick it in. Again, and just to clarify, this is all idiot proof and you can't mess anything up on any of this.

SSSooooo, you'll feel the rack screw bar with the fuel and torque screws. Just push on whatever you run into in there. The more travel, the more servo movement. All you're doing with your finger is makin sure another bonehead wasn't in there playin. Make sure when you push it all the way in (about 5/16" travel plus change is about 425hp stock, but doesn't really matter how far it does go) you can feel about .030" or so (just picture a .030" gauge and guess, really) of secondary spring pressure. That is the torque spring on the stop bar. It doesn't have to be exactly anything, just want that little bit of extra pressure for torque rise. I won't explain it all, but your feeling torque spring pressure from the screw making sure someone before didn't turn one screw out from the other (doing it wrong).

There are two screws side by side. If there is no pressure there, turn the outer most screw (towards you) in until there is. Do this with a 1/4" drive 3/8" deep socket (12 point is easier) with baby vice grips clamped to the very end as the lever and a sumthin stupid like a 7/64" Allen wrench down the center. Just take your Allen set and stick it in the end of the screw to find the size (or call your local dealer, ask for truck shop and just ask em what size). Insert socket, break loose counter clockwise with Allen wrench in hole, turn screw and lock back down. If your torque pressure feels OK, or you reset it as stated, back out both screws evenly to the tune of about 20hp per turn or so. Wipe off housing and cover and stick back on with original gasket. No glues on anything anywhere here.

If the truck’s in good shape, go 3 turns or so and run it a round. If your pyro stays below 950, meaning it's timed close enough to stock or advanced properly, turn it out another 3 and call her good. That's it. Have fun. It can be super tweaked with meter timing and gov. removal, but you'll be pretty happy like this unless you run into me on the road somewhere.

Want peace of mind and better mileage, take it to someone trustworthy (Cat dealer, and tellem you want an old timer on it) and set a tight overhead ($225 or so) and meter time ($100) to (for your 92) 17.5 degrees at 1000 and start at 1230, plus remove the stop screw and toss it. This won't make sense to you but that's exactly what you tell him. He'll know just what you're saying, believe me. That'll land you between 5.2 and 5.7mpg depending on what you haul, and between 530 and 560 hp. You'll know it all worked when it goes from 20psi boost to 27 the first time (3 turns) and 32+ the next (3 turns). Add an 0R6051 turbo for a couple more pounds and better power (will now be a core charge tho). And don't worry, it'll all take it just fine.

With more exaggerated tuning, she'd pull 800hp just as it sits with no motor mods whatsoever and live to 750,000 miles without a hitch. If you're running 15psi boost right now and the first 3 turns didn't increase the boost, have the dealer replace you air fuel ratio diaphragm ($100). Have fun...T
ynot is offline  
The Following 14 Users Say Thank You to ynot For this addition to TDG:
122 cat (05-20-2010), 2broke2payattn (05-29-2013), 34kw (04-29-2012), AaronF (06-04-2013), benitog1971 (02-03-2013), chordy80 (04-29-2012), dotcomdmc (04-06-2014), heavy hauler ont can (04-11-2011), jdub63 (09-09-2014), nevrenufhp (01-28-2009), OldHoods#1 (10-04-2013), Oxbow12 (01-18-2013), Rogerstar1 (07-21-2010), TIZDEEP (04-18-2013)
post #3 of 4 (permalink) Old 01-05-2010, 01:24 PM
 
Join Date: Jan 2010
Posts: 3
Points: 1,279
Thanks: 1
Thanked 0 Times in 0 Posts
can anyone tell me if you can meter time a fully mac. 3406c. its a 8pn motor. Or is this on comp. motors that are meter timed.

Last edited by pep88per; 01-05-2010 at 01:29 PM.
pep88per is offline  
post #4 of 4 (permalink) Old 02-16-2012, 04:14 AM
The other guy
 
Join Date: Jan 2007
Location: Brenham, Texas
Posts: 3,936
Points: 105,540
Thanks: 36
Thanked 1,350 Times in 846 Posts
Quote:
Originally Posted by pep88per View Post
can anyone tell me if you can meter time a fully mac. 3406c. its a 8pn motor. Or is this on comp. motors that are meter timed.
ALL engines with a fuel line can be meter timed in one way or another
ynot is offline  
The Following User Says Thank You to ynot For this addition to TDG:
jdub63 (09-09-2014)
Closed Thread

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Diesel Truck Forum - TheDieselGarage.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



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
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome