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Piers Diesel Research governor spring installation instructions
Install the Piers Diesel Research Governor Springs
Add some power to the top end of your engine

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After you have installed the TST torque plate and adapted your driving to it, you will begin to feel that that the engine is running out of steam too soon. The governor begins to restrict fuel rack travel as early as 2100 rpm. and by 2250 rpm the game is over and the engine will not accelerate under a load. This can leave you stuck in 3rd gear with a load on a mountain grade because the engine can't pick up enough speed to allow you to shift into 4th gear. The Piers Diesel Research 3000 rpm governor spring kits will allow the engine to pull strongly to at least 2700 rpm before the governor begins to pull back the fuel. A 4000 RPM spring set is also available, but you also need to install 60 psi exhaust springs for engine speeds above 3000 rpm. Installation of the governor springs is not difficult, but a beginner may want to have help available.

The instructions supplied with the spring kit install the springs through a port in the side of the injection pump. Because I needed to replace a leaking fuel return line, slide the TST torque plate a little, and adjust the AFC travel, I chose to install the springs through the top of the pump while I had everything apart. Here is how to do it:

Tools needed:

Important:  Keep your parts and tools clean and don't knock dirt or debris into the injector pump!

 1.    Remove the lower band clamp on the turbo boost hose (7/16" wrench).

 2.    Remove the oil dipstick clamp bolt from the intake horn (10 mm wrench).

 3.    Remove the five intake horn bolts (10 mm wrench) and remove the intake horn with the boost hose attached.

 4.    Loosen the hose clamp and remove the wastegate hose from the AFC control (screwdriver).

 5.    Remove the boost sense line from the back of the AFC housing (1/2" wrench).

 6.    Remove the two AFC housing bolts on the fender side - these also hold the fuel shutdown solenoid bracket (8 mm wrench).

7.    Remove the two AFC housing bolts on the engine side (these may be 5 mm hex key or phillips screw heads depending on what you installed with the TST kit)

 8.    Remove the AFC housing and set it aside.

 9.    Remove the two torque plate screws and the torque plate (screwdriver).

10.  Look into the pump below where the torque plate was. If you can see the governor weigh and spring, bar the engine forward (15 mm wrench on the crankshaft pulley bolt) or backward (22 mm wrench on the alternator pulley bolt) until the spring is positioned in the center of the open space. This position will be off center toward the fender side of the pump so that the spring and retainers can clear the fuel rack lever. If you can't see the weight and spring, bar the engine until it appears.
11. Use a dial or vernier caliper to measure the distance from the top of the governor stud to the top of the governor spring adjustment nut. Take several measurements with the caliper as straight as possible, and write the measurement down. Note the position of the adjustment nut so that it can be returned to it's original position. The stock measurement should be about 0.060" or sometimes a little more.
I did not have a strong mechanic's magnet tool, so I taped a 1/4" x 2" rare earth magnet to a screwdriver.
12.  With the magnet inserted into the space to the right of the governor weight (see photo in step 10), put the tip of a large screwdriver on one side of the slot in the nut to slowly unscrew the nut from the stud. The nut has positive click stops every 1/4 turn, so don't get worried if it keeps stopping. When the nut has backed off far enough to get the screwdriver to fit into both sides of the slot, proceed carefully (the magnet will catch the nut if you drop it). When the nut is almost loose, put your magnet on the nut and use the screwdriver to finish unscrewing it from the stud. Hold the retainer washer in place with the screwdriver and use the magnet to remove the nut from the governor. NOTE: You do not want too many parts stuck to the magnet at one time, one of them is bound to fall off and get lost inside the pump.

 13.   Use the magnet to remove the spring retainer washer while you hold the springs in place with a screwdriver.

 14.   Use the magnet to remove the inner spring while you hold the two outer springs in place with a screwdriver.

15.  Use the magnet to remove the next inner spring and be careful if some shims stick to the bottom of the spring. Hold the outer spring in place with a screwdriver.
16.  Use the magnet to remove the shims (there are usually three) and the spring seat from the bottom of the spring pocket. Use a screwdriver to hold the large outer spring in place; it will not be removed.
17.  Carefully install the new spring seat and the two inner springs. I put each part on the shaft of a thin screwdriver, then placed the end of the screwdriver on top of the governor stud and slid the part down the screwdriver and into position. Install the seat first, the middle spring second, and the inner spring last. The old springs, shims and seat are not reused.
18.  Here is the really tricky part - the retainer washer is too big to go straight in, so be very careful. Use the magnet to finesse the retainer through the available space and onto the stud (the retainer will try to stick to everything on the way in). Note that the stud is flattened and the retainer has an oblong hole to keep it from rotating on the stud. You will have to work with the magnet and a screwdriver to get the retainer hole aligned with the stud. FWIW, I tried to slide the retainer down the screwdriver, but it would fit through the space and, while I was wiggling it around, the screwdriver lifted off of the stud and the retainer disappeared into the oil at the bottom of the pump. I eventually retrieved it, but I do not recommend sliding the retainer washer down a screwdriver shaft!
19.  Install the nut and screw it down until the caliper measures the original distance from the top of the stud to the top of the nut. The nut slot should be back in its original position.

 20.  Bar the engine 360° until the other weight appears. Repeat steps 10 through 19 for this side.

 21.  Reassemble following steps 9 through 1 in reverse order.

Start engine and check idle. If the truck will not idle, but the engine easily reaches 3000 rpm, adjust the idle and take a test drive.

If the engine will not idle and struggles to reach 3000 rpm, the nuts need to be tightened one or two clicks.

When properly adjusted, the engine will pull hard to about 2800 rpm before the governor now begins to pull back on fuel delivery and the idle will be smooth with a clean transition to higher engine speeds off idle.
HEMIŽDart posted to the TDR Forum: A touchy idle indicates that the nuts are too tight - adjust both nuts a click at a time until the idle and high end both seem reasonable. A setting of 0.030-0.040" will give you a soft pedal. You'll get a real crappy idle. I hated the soft pedal. My truck is set @ about 0.055".

From TDR Thread 3k today!!!!WOW!!!!
After installation, the idle should have only dropped or raised a little bit, if it raised or dropped a lot then the springs are too tight (idle raises) or too loose (idle drops). When you install the springs, tighten them till the very first's light, then go 2 more clicks and try that. See were the idle is and go from there. You might have to put one more click on them but it just depends. If they are too tight you won't like it on cruise control.

What if disaster strikes and you loose a part in the pump?

Don't panic! All of the parts are steel - take a break to calm down and then fish for the lost item with the magnet.

If you can't find the part, temporarily remove the injection pump pump lock pin (24 mm wrench) and allow the oil to drain out of the pump (don't loose the copper sealing washer for the pin cover). With the oil level lowered, you may be able to see the missing part. If you can't see the part, you can easily tell where is has to be - fish for it with the magnet, and then carefully work it out of the confined space at the bottom. Believe me, it is much easier to find and retrieve a missing part when the oil level is close to the bottom of the pump.

Other TDRoundtable notes:

To Install 3k Gov Springs
WHo's installed there own geverner spring kit???

Strick-9 writes:
My advice is to go in through the plug on the side of the pump instead removing the camplate and going through the top. You reduce the chance of dropping things and the nuts are much easier to get to. You will have to remove the shutoff solenoid lever. The trick is to turn the key on and bump the starter to pull the shutoff solenoid up. That removes the spring pressure so you aren't fighting it. Don't lose the tiny half moon key on the pump and you're home free.

You will also need some type of device to turn the preload nut with. It would normally take a huge screwdriver (1/2" wide) but the stud comes up through the center. You will have to grind away the center where the stud pokes through. Some people have used copper tubing. You beat one end flat and then grind away the center. I tried this, but kept bending and breaking it. I finally took apart an old barn hinge and ground out the shape I needed. This was much stronger than the copper and has held up so far. Plus, it's flat and I can twist it easily with my hands.

Once you have the tool, the only trick is to measure how much the stud sticks through the nut. If you go through the side of the pump you can feel the stud and see it. If you go through the top, you will need to use the bottom of a set of calipers to measure the stud length.

This is the only critical measurement. If they are too tight, your idle speed will be high. If you just try to lower the idle speed, your truck will not start unless your foot is on the throttle. The pump requires a certain throttle angle for starting.

If you get them too loose, your idle speed will be too low and after you idle it up, the idle may become too sensitive. You may fight no engine braking or hanging RPMs (not returning to idle) or you may not be able to idle the truck at all. Sometimes they will idle at 500 and the slightest increase of throttle jumps to 1500 RPMs with nothing in between.

JGK writes:
Here's what I can add. I went through the plug on the side. I had to cut the sealing wire, which requires a commitment to "violating" the pump. On the other hand, I have a plate and the AFC kit, so... However, since the springs are right there, I felt it was probably easier then coming down through the cam plate hole.

I found that removing the shut off solenoid did not give me the clearance I needed to remove the plug. There is an arm held on by 2 10mm bolts that hold a stop screw that the shut-off lever will hit against. I loosened the rear one and removed the forward one (don't lose the spacer) and rotated it up.

I still couldn't get the plug out 'cause it hit the bolt that holds the shut-off lever on it's shaft. I needed to remove that. I was real leery about doing that because I wasn't sure I could put it back on in exactly the right place. It turns out it has a woodruff (?) key. The bolt is 8mm. The arm slides right off. Just don't loose that little key. With the AFC housing off and these two levers out of the way, access is pretty good.

I tried to paint the keeper nut like the instructions show, but the paint didn't stick (even wiped the keeper down with carb cleaner). I measured from the slot to the top of the stud and from the raised surface of the keeper to the top of the stud to get 2 measurements. This helped a great deal. Be aware your caliper can show big reading swings depending on how off-parallel you are to the stud when measuring. 2 different measurements helped.

I used not only the pencil magnet but a dental pick as well. The springs are nearly horizontal when working through the plug and that made it a little trickier getting them out. The pick helped since it's hooked. A small stiff wire with a hook on the end would work. You're not likely to loose a spring in the governor housing, except for maybe the smallest one, but you could loose a shim or a spring seat. Just take your time.

I found that pulling springs out from the biggest to the smallest worked best. Watch for shims. Only those on the biggest spring, if any, are retained. None of the big shims came out on mine. Only the one on the next-to-the-smallest spring came out. Once the springs are out the magnet works good to pull the seats and shims (if not stuck to the spring) out.

Work in reverse to put the new ones in (seat first, then smallest to biggest springs).

My retainer nut did not screw back to exactly the same position to get to the original measurements. So measure several times before removing it and trust them when putting it back on.

Have a really good light right down the hole when working. A tube-shaped fluorescent work light is ideal. Also, A mirror on a stick helps to look in the hole to verify things.

Jimk writes:
I did not take off the arm on pump that is over the plug, but I had to rotate it to the exact spot to get the plug out. The first thing that I did not like was the oil that ran on my floor of my shop when I pulled out the plug. I wish I had pulled out the plastic liner that is mentioned in another post. Hard to see in the hole. I was not sure what the bottom seat was and there are a lot of shims in there also. I thought is this all of the shims or did one fall into the oil in the pump. Finally when I got it back together I started the truck up and it ran fine, go idle ect . I want to thank Chris and few others for the help. Can the rubber boot be bought by itself for the fuel solenoid

JFulmer writes:
I also told him about the fuel shut off arm and if you take the top bolt out and move it out of you way the plug goes back in much easier, took me 20 min to figure that one out.



Last Minor Update: August 20, 2003