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Something is wrong with gov springs?

12K views 37 replies 5 participants last post by  Insubordinate 
#1 ·
Short back story, bought truck with aftermarket gov springs already installed by previous owner. Idle was low when I bought it (550-600rpm). Day after purchase, tried to adjust idle up to 750rpm. Anything above 600rpm would cause throttle to hang or even cause the RPMs to rise on their own. Not linkage related problem. Turned idle back down to 600 and drove it. Only issue I have, is that I can't hold 1200rpm with the throttle. It either wants to jump up to 1800rpm, or just fall back to idle.
Why do I want to hold 1200? It's cold outside, and I bought a high idle solenoid to keep the idle up.

Read on here that gov springs could be set too tight? Finally pulled the plug on the side of the pump, and checked them out. The stud was sticking through the nut quite a bit. I've read that you can loosen the nut with a screwdriver, but that wasn't possible on mine due to the stud protruding.

So, i made a tool to loosen the nut (like a flat head with the center cut out).

Began loosening the nut, and it took a half turn to make a "click". From reading that you should be able to loosen the nut with a screwdriver, I assumed that the previous owner over tightened them by a lot.
So, after that initial click (which took half turn), I loosened them 2 more clicks (which only took 1/4 turn each). That put the nut approx 0.030" ABOVE the stud. Now you could adjust nut with a flathead like I've read.

Spun the engine over, and the other spring set was identical... First "click" to loosen was half turn, and each after was only 1/4 turn.
Set it to match other side. Approx 0.030" above stud.


Put it all back together, and truck wouldn't start without throttle. Bumped idle screw up to where truck would start, and now the throttle hangs even worse than it did before. Again, not linkage related. I can back idle screw off completely (to where truck won't run without throttle) and there are no issues with throttle hang.


So what's going on here? I pulled afc housing and fuel plate off to look down inside and see if anything were binding, but I really have no idea what I'm looking at. I'm probably not the right person to be doing this, as I've never done it before, but hoping for a miracle.

Does the pump need to be rebuilt or something?
 
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#2 ·
Nut above the stud .030? As just about to fall off?:shock:
Stud suppose to stick out of the nut .040-.050. Look up pac-brake GSK installation instructions online. You can use flat head screwdriver on one side of the nut just like others do.
If I understand you correctly, then I wouldn't even start the truck anymore till you tighten up your nuts lol
 
#3 ·
Yeah, I set it to where the nut is slightly above the stud.... Guess that's not correct! I'll try tightening them back up tomorrow morning and see if that does anything.

Maybe they were just over tightened to begin with, and I over loosened them? Do the 2 have the same effect on the idle and throttle hanging?
 
#4 ·
Yes its all in your springs. Sometimes it takes a lot of tinkering with them to get it right. Ones you set them to .040-.050 and if you not happy with the results, then you go one click at a time and no more than 2 clicks either direction
 
#5 ·
Tore back into it this morning and tightened them back up 2 clicks, which is basically just 1 click looser than they were before I started messing with them. The stud protrudes above the nut now.

Fired it up and started messing with the idle. At 800rpm idle, it fires right up without giving it any throttle and sounds good. However, when I rev it up, the RPMs take off on their own and I have to shut it down.
With the idle set at 750rpm, you have to give it a tiny bit of throttle to get it to fire right up. When you rev it, the RPMs hang for a couple seconds before coming back down. Tried driving it like that, and every time you push the clutch to shift, it sounds like you still have your foot on the throttle. Not going to work there.
With the idle set at 700rpm, you have to give it some throttle to fire up. RPMs don't hang as bad as they do at 750rpm. But it still seems like they hang very slightly. It's driveable like this.

I ended up setting the idle at ~675 to make it more driveable. You do have to give it some throttle to get it to start up. I still can't get it to hold 1200rpm smoothly. It either wants to keep rising to like 1700-1800rpm, or it wants to just drop below.


So, based on this what do you guys think? I'm not happy with it, and if this is how it acts with gov springs, then I'd rather have it back to stock.
 
#6 · (Edited)
Did he put real governor springs in or do the washer mod? Did he say it was specifically a 3k kit or is that just your best guess?

I put a Pac-Brake 3k kit in mine, tightened the studs to the same protrusion as they were when I opened it, and no driveability issues at all. Just lots more fuel between 2100 and 2900 rpm. I had to lower the idle speed a little to put it back to spec, but that's the only adjustment I had to make.

My truck starts with no throttle, even after sitting overnight in the mid 20s without being plugged in and only one cycling on the grid heaters. Warm idle is just a touch over 750 in drive with the A/C on. Runs 900 or so in park/neutral.
 
#7 ·
Did he put real governor springs in or do the washer mod? Did he say it was specifically a 3k kit or is that just your best guess?

I put a Pac-Brake 3k kit in mine, tightened the studs to the same protrusion as they were when I opened it, and no driveability issues at all. Just lots more fuel between 2100 and 2900 rpm. Had to lower the idle speed a little to put it back to spec is the only adjustment I had to make.

It's a real 3k kit. Receipt for them was in the box of stock parts that he gave me, along with a ziplock bag that had all of the stock springs in it.

I'm thinking about just buying a 4k kit and completely redoing them?
 
#8 ·
You should take them all out including idle spring and make sure there is no shims left and all springs are exact same size and count as the second set from opposite side. There was a guy here little bit ago with one spring completely missing. You never know what previous owner did. even putting back to stock you might have same problem, because factory balance then and add shims if necessary. You better off just get new set of 3-4 GSK kit, you need it with your mods anyway.
 
#10 ·
With how I have the truck setup right now, it's drivable, so I'm going to order a brand new 4k kit and just completely redo it rather than just messing with what's in it. Hoping I can get it sorted out!
 
#13 ·
Just dug through the box of parts that I got from the previous owner, and found the stock gov spring kit in a ziplock bag. Here is a pic of everything that was in the bag.

Can you tell anything from this?


 
#15 ·
Ok, gotcha. Would leaving some shims in there possibly cause the issues that I'm having?


On a side note, I finished hooking up my high idle solenoid. It's a Vanner Autothrottle: http://www.vanner.com/manuals/73-46.pdf

Once you get it installed, you can adjust a single nut on the solenoid itself to fine tune your high idle point. The adjustment is very precise and steady.
Here's what I noticed:

I was adjusting the high idle point very slowly while the truck was running. I could get it up to around the 850rpm mark, but the slightest adjustment past that point, would send the engines RPMs up to 1700-1800rpm. Once the engine "took off", I had to back the adjustment almost all the way back down to stock idle before the RPMs would drop back. This explains what I was feeling with my foot inside the truck, and why I can't hold any rpm under 1700-1800.


I went up to visit my dad today, and he has a 1995 12v, that has the stock gov springs in it. I fired his up to see how it felt, and it was very easy to hold ANY rpm that I wanted. It would hold that rpm rock solid.
This is how I want my truck to be....
 
#17 ·
Hmmm... Mine is definitely a 215 pump. I'm going to see if I can find a picture online of what you are referring to.
Maybe I'll just build up the courage to remove the springs tomorrow and see what's in there. Tomorrow is supposed to be around 60 degrees, but then it's supposed to snow and ice next week, so it would be awesome if I could get my high idle solenoid to work properly before the weather hits
 
#18 ·
So I've been reading the PAC brake gov spring instructions, shown here: http://www.pacbrake.com/PDF/L5658.PDF


And noticed that their kit includes Large, Medium, and Small springs. It says that you only use the small springs if you want to make it a 4k kit.

Looking at the picture I posted above of what's in the ziplock bag, it looks like the small springs mentioned in the PAC brake instructions?
Is that correct, or do the factory gov springs include a small spring like that?
 
#20 ·
Ok I'm wrong. I just asked my friend if he remembered how many springs I brought to him when we put my stockers on his truck. It was 3. 4 total including idle spring that you suppose to reuse with GSK kit. So you got all of them. His truck was less one.
I definitely had two piece holder. Is yours solid piece? its probably doesn't matter anyways.
 
#21 ·
Just a thought, but when I put GSK springs in mine, I had only two sets of springs to remove from the originals. You have three. Maybe the two larger ones should have been left in since these may be the idle speed control springs.

Don't ask me why I think this!.
 
#22 ·
The previous owner of your truck forgot to take out two shims. Here is a picture of the original governor springs and shims that came off of my stock pump.
http://postimg.org/image/sgx1jf7on/
 
#24 ·
The previous owner of your truck forgot to take out two shims. Here is a picture of the original governor springs and shims that came off of my stock pump.
View image: 20131202 092640

Good info, and thanks for the pic! I'm going to just tear it apart this evening and see what all is in there. I'll take pics and post up what I find.
Wish me luck. Lol
 
#25 ·
So from your pic, it likes like there may be 2 large shims still in the pump on mine, and it's possible that he left the 2 piece holder as well?
Do I have that right?

And also, are those big shims under the largest spring that you remove, or do you have to take out the really big spring as well to get to those shims?

Thanks for all of the help, guys
 
#26 ·
I almost forgot those two shims as well. I didn't think there were any more, but there sure were. A stick magnet with a SMALL tip (like $2 from the auto parts store) worked like a charm. Good luck! I get to do 4kGSK on my brothers truck soon enough. :p

Edit for previous post:
I took out everything, then put it all back in piece by piece. To be honest, I'm not 100% sure how it was all stacked up.
 
#27 ·
Sounds good. I'll pull everything out and make sure that there are NO shims left anywhere. Lol
 
#29 ·
Ok guys, just pulled 1 of the gov spring assemblies out of the truck. Used a magnet and made sure that I got EVERYTHING out, including the big spring that most people leave in.


This is what I pulled out:





I'm guessing that those 2 items that I set aside from the springs are NOT supposed to be in there. They look just like the pic that Insubordinate posted.

So, that looks to be my problem. 1 thin shim left in there, and also the other half of that 2 piece factory spring base.

Also interesting to note, is that I measured the stud protrusion before pulling it apart, and it was right at 0.041". However... To get the retaining nut off, it made like 8 solid clicks. I'm guessing that's due to the excess tension that was on the springs due to those extra parts being left in?
 
#30 ·
Also, one more question before I put this side back together. See that large thin shim that I pulled out?
It was right under that BIG spring. So, since most people leave that spring in there, should I put the shim back under it?

Here's a pic:

 
#33 ·
Thanks! I put the big spring and it's shim back in, along with the other 2 springs and seat.

Got the nut put back on, and am trying to get the stud protrusion set right. Seems like I get a different number every time if measure with the calipers! Lol
 
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