BOSCH PUMP VE GUIDES - Gov-mod.

[Dan!]

Governor shimming guide

Firstly I removed the minimum and maximum throttle arm travel screws. One is on the front of the pump and the others on the back. Both held in place by a 10mm locknut, and removed using a flathead screwdriver in the end of the screw. The front one is circled below:



Next up you want to mark the position of the throttle arm in relation to the splined throttle shaft. You should scratch a line on the throttle arm in line with the indent on the top of the shaft, as you can see I did in the photo below:



Now you can remove the throttle arm. This is held on with the 10mm nut around the splined shaft. As you undo it, keep even pressure on the throttle arm to hold it down, this just stops it flying off and breaking/getting lost. When the nut is removed you should be able to lift the throttle arm and the spring around it off, with a little bit of wiggling.

Now find the max fuel adjustment screw, located here:



Slacken off the 13mm locknut, then wind the screw out almost all the way, so its just hanging on by a thread or 2. This puts less tension on the gov shaft, and makes it easier to remove.

Now you want to remove the main 4 Allen/torx bolts that hold the top and bottom of the pump together. These should be relatively easy to find, one in each 'corner' of the pump. Remove all of these and now handle the pump very carefully, as the top is loose but still connected to the internals of the pump.

If you gently wiggle the top of the pump up, the splined throttle shaft should fall out of the top of the pump (it may need some persuasion, but don't be to forceful!).

Once this is out you only have to remove the small spring connected to the cold start lever. This should just slide off with the help of a little screwdriver. Now the top of the pump should just pull away, obviously be very careful removing it, just in case anything gets caught etc. Once the top of the pump is off, you should be left with this:







Red arrow is where the gov assembly has to slide into, blue arrow is where one end of the cold start spring hooks onto.

You should be able to clearly see the governor assembly (riveted to the splined throttle shaft) and now you can remove it. If you look where the shaft sits on the bracket inside the lower part of the pump, you should see a little flat section, which you will need to rotate, and then wiggle to remove it from the bracket.

One it is removed it should look like this:



From left to right, Main spring (the one you need to shim), Intermediate spring and then the idle spring.
Now you need to remove the shaft and springs from the cradle. To do this, compress the springs slightly, and it should pop out. Be very careful doing this as the gov' shaft and cradle are both very brittle and if they break you will need to source a new one, not cheap!



Now for the tricky bit.

You now have to remove the small circlip on the 'main spring' end of the shaft. Again compress the spring slightly and then using either a small screwdriver, or witchcraft, remove the circlip (be very careful and don't lose it, as its very likely to ping off and make a bid for freedom!) then slide off the spring seat and main spring.
Now you need to find a suitable 'shim', either 2/3 small washers, a small nut, whatever! As long as it's not made from plastic/wood or is way too big etc. I used a small nut, and 1 large thin washer on mine, see below:



See the small nut and large thin washer in the main spring section.

Shimming it around 3/4mm is about the average, much more and you will struggle to get the assembly back together and in the cradle. Much less will just have less of an effect.

When you are happy with the shimming, you can put the main spring back on, and then the main spring seat. Now you have to compress the spring to get the circlip back on. Again being very careful not to let go/drop it all, as it will all go flying and get lost!

Once the circlip is back on, double check everything is in the correct order, and put the assembly back into the cradle, again compressing the assembly and being careful not to snap anything.

Now you have done all the hard stuff, re-assembly is simply the reversal of disassembly, but here is a quick run though just to make it easier:
- Wiggle gov shaft back into bracket in lower part of the pump
- Re-connect little cold start spring
- Push splined throttle shaft back into the top part of the pump
- Let the top section carefully fall into place (If it wont go back down smoothly and easily DON'T force it, something has either moved/got stuck. The throttle shaft was quite tricky
- When its in place and your happy, put the 4 main bolts back in, and tighten up.
- Re-fit throttle arm ON THE CORRECT SPLINES! Make sure the notch on the shaft lines up with the scratches you put on the throttle arm earlier.
- Tighten throttle arm down
- Re-fit min throttle arm travel screw at the back of the pump
- Dispose of max throttle arm travel screw (Or keep it as a spare for the MOT...)



I think that's everything!

Dan.

[ginge191]

so what kind of gains does this give mate??
Im after some niiiice low end boost, thinking i may have to ugrade some internals at some point aswell :/

[Dan!]

As far as I know the standard gov starts to cut fuel at 3k and massively reduces the fuelling past 4.5k, making it hard to rev any further than that. Shimming the gov means that (depending on the level of shimming, usually around 5mm) fueling wont start being reduced until much later in the rev range and if you have a large enough turbo (Bigger than T2 kinda territory) you can run the engine round to ~7k.

If your planning on having a small turbo (GT15/K03) for more torque/faster spool then you wont see massive gains from a gov mod as the smaller turbos are out of puff by about 4k anyway, but if you have anything larger then its a mut have tbh, totally changes the way the car drives imo.

[studturbo]

going to do this tomorrow good guide dan

[studturbo]

its not as hard as what you think i did it all with in 40mins thanks too dans guide good guide dan
my gt15 holds it boost now but i think the gov mod as killed it making a funny noise now aha

[Bananalad]

Is it much harder to do while the pump is on the car?

[studturbo]

no not really

[padge]

Thought you needed a gov cradle stu?

[studturbo]

Yeah a do cracked mine skimming it again

[studturbo]

when thay say there easy too brake u aint kidding lol

[Mattcheese31]

when thay say there easy too brake u aint kidding lol

don't say i didn't warn you . . .

[studturbo]

got a new gov cradle hope i dont break this one

[Tom]

I just done mine, took me 2 hours but i did have Zombieland on aswell, getting it all back together was a right pain, i though that was the hardest bit.. That throttle shaft is a right pain in the arse.

[studturbo]

after i got my new cradle i put my pump back together well easyier took me 20mins lol

[Tom]

after i got my new cradle i put my pump back together well easyier took me 20mins lol

Was your throttle shaft really stiff? Mine just did not want to go back in the damn hole :/

[Mattcheese31]

after i got my new cradle i put my pump back together well easyier took me 20mins lol

Was your throttle shaft really stiff? Mine just did not want to go back in the damn hole :/

you should lube the throttle shaft up with veg or diesel mate . . .that's why you struggled .

[studturbo]

[/quote]
you should lube the throttle shaft up with veg or diesel mate . . .that's why you struggled . [/quote]

i did mine with a little bit of grease went in easyier

[Tom]

Yes thanks guys I used vaseline in the end lol but only a little bit so its all in the hole not in the pump

[studturbo]

Yes thanks guys I used vaseline in the end lol but only a little bit so its all in the hole not in the pump

good good u find it fiddly then ?
stewart

[306__xrdt]

Hi Very nice guide.
I am from Norway and i ahve a 306 XRDT the problem is that the max fuel screw has snapped off, quistion? is itt hard to replace the screw?
I have ordered a new screw, is itt also a good idea to change sealing att he same time?
Sorry for mine bad English.

Have a nice day

[londondan86]

Hi Very nice guide.
I am from Norway and i ahve a 306 XRDT the problem is that the max fuel screw has snapped off, quistion? is itt hard to replace the screw?
I have ordered a new screw, is itt also a good idea to change sealing att he same time?
Sorry for mine bad English.

Have a nice day

As long as you can get the old one out, it will be an easy swap. Yes there is a black o-ring which should be replaced at the same time but chances are it will be ok to be re used.

[Dave]

Don't remove the screws on the outside of your pump else you will end up bending stuff in your pump when you gov mod it.

[Mattcheese31]

Don't remove the screws on the outside of your pump else you will end up bending stuff in your pump when you gov mod it.

confused as to which screws you mean Dave? . . . .

[306__xrdt]

I know i only need to get off the pump lock and to get out the screw i have ordered a new screw and copper sealing.
The good guide does have a quistion, where can i see on the picture with some scratch on the trottle arm? to mark the position? is that the white scratch pointing to the left?
Is itt a good idea to order a timing tool on ebay? becouse black smoke wil not pass the mot i quess

Thank you very much

[Dave]

The one that limits max fuel throw, the one circled in the first image.

[Mattcheese31]

The one that limits max fuel throw, the one circled in the first image.

really confused mate, that is on the outside, how will that make any difference to gov modding? . . . . .sorry if i'm being stupid i am full of man flu atm . .

---

ahhahhhhh . . got it! . .you mean too much pressure on the gov assembly without the screw to stop max travel yeah? . .

[Dave]

Govnor modifying means you're removing the ability for the pump to resist your throttle action, which would normally happen on the spring. With too many shims the pump cant 'cushion' the effect of your right foot and will transfer all the force from your foot into the delicate leverset if not setup properly. Its like pulling a spring one way, and the pump pulling it back the other, and with modifying the govnor, this overcomes this force, but you dont want to overdo it where your foot action overcomes the amount of compression that would normally happen with a stock govnor spring, but you're making it unable to be compressed by shimming it.

Technically speaking, if you use a longer throw cradle then you dont even need to touch the govnor spring/shims etc, just purely pull it further to the point where its almost fully compressed. The govnor only compresses so far before its solid, its just as stock then its not far enough unless you do stuff like this and then set it up ...



So if gov modding, leave the convensional screws and find the limit of the pump, if you're not, then look into this ^

[londondan86]

I assumed he meant the actual max fuel screw (circled in the 3rd pic). Well confused now!!!

[Mattcheese31]

What leaving it off Dave? . .

[306__xrdt]

Yes i am sorry for the misunderstand confusion, itt is correct with the 3rd picture the max/min fuel screw that has bin broken due a work tool droppet on the screw and cracked off.
So i have looked here and there on the internet and i found this great guide that whe dont have in Norway.
And i was reading this guide and watched pictures how to open the pump?...no more than that
And how to put it the correct way back again, i quess he means do not screw off those 2 bolts for the trottle arm setting ore otterwhise it wil be inccorect setting for the trottle and put allot off stress on the pump.