govenor removal

[dieselpower]

ok...i removed the govenor springs and it all went back together fine but during WOT the pin that slides along the cone in the lda gets pushed out and stays there....i checked out an unmodified pump i had and the same thing happens but the pin is springloaded on the unmodified pump so I can push it back in even with the throttle lever wide open. im thinking that the spring action is caused by the govenor and intermediate springs. has anyone else noticed this and does anyone think it will do any damage to the pump?
thanks for the help

[vwmike]

So my educated guess, is yes, early 8-valves use dual springs.  

Anyone else have evidence to support or deny that observation?

ALL of the 8v and 16v engines up through 95 or so had dual springs. Autotech, TT, and Crane offer replacement valve springs. I don't know where the Crane ones come from, but I have heard the Autotech ones are actually TT springs. There are some other companies out there who also offer springs, but I've had good luck with the Autotech/TT springs so far.

[AntonUK]

hey dieselpower,
As far as I can see your situation, shouldnt the the LDA pin push the riding pin back into the pump as the LDA pin will return to its high position when no boost by its spring thus pushing the pin back into the pump by the LDA pins profile? maybe I havnt understood your problem properly or you might not understand me either  :?

[dieselpower]

yes...thats how it works, except the pin gets pushed out and stays there( i cant push it back in any way) when i am on the throttle...it just wont move and i think it will be binding against the lda cone and wreck something.  the other pump i looked at doesn't do this so i don't kno if the pump is wrecked somehow or if its because of the govenor spring being preloaded soo much.
thanks for answering tho



Mark

[hillfolk'r]

back in the day i had a 79 engine in a 84 4 door rabbit,,well i found out it was one of those lil 1457 engines,,i hung all the euro gti stuff on it,cam tb,intake,header,distributor,,it was like a na diesel to 4500,then it kicked ya in the arse till 7500,with stock springs,,well this went on all summer,,it loved it,,but one night i got happy doin burnouts,and it developed a rod knock at 8200 rpm,,so i limped home,and i actually ended drivin it all week to work(10 miles each way),before i swapped in another boneyard engine,,so the only thing i see holding back the diesel to rev is not the valvetrain,,its the pump,,or like someone else said,,will it not ignite fast enough at way hi revs??,,besides the stock power peak is at 4800,,so whats the sense of 8k if you have a stock cam??it wont flow up there,,i believe the power peak will remain the same place,just way higher,with turned up pump,boost etc,,deos did on the dyno a few years ago,,was like 115hp at 4600,and 139 ft pounds at 2800,,pretty close to stock peaks,,just way higher on the curve

[dieselpower]

ok,
a little off topic but who has actually changed or removed their govenor? and how did you do it? im asking this becasue me and Leprechan shimmed both the intermediate spring and the main spring and we are haveing issues controling the revving, like the rpm's wont drop once they go high enough. anyway im just wondering if maybe i did something wrong.
any help would be appreciated


Mark

[fspGTD]

The governor spring is required to prevent a bind at WOT between the LDA control cone and the throttle stop lever that is inside the LDA cover.  If you just shimmed the governor springs solid, something could get bent.

When you press down all the way on the throttle input, the control cone feeler needle moves toward the control cone.  The position of the control cone determines how far the feeler needle can move.  And the distance it's allowed to move at WOT determines the fueling level.  As the throttle lever is pressed down progressively, once the feeler needle touches the control cone, any further movement of the throttle lever causes the govenror spring to take up the slack.  Us who have shimmed the main governor spring can feel this point as the throttle lever becomes noticeably harder to press down further.  If the governor springs were removed entirely and replaced with solid linkage (like shims replacing the governor springs), then pressing the throttle down further past the point that the feeler needle contacts the control cone  would either force the boost diaphgram upwards against the boost pressure so the feeler needle can move inwards (not very likely due to the narrow angle of the contorl cone and the friction of the needle on the control cone) or cause something to bend.  That is why I would not recommend replacing the governor springs entirely with shims.

[fspGTD]

back in the day i had a 79 engine in a 84 4 door rabbit,,well i found out it was one of those lil 1457 engines,,i hung all the euro gti stuff on it,cam tb,intake,header,distributor,,it was like a na diesel to 4500,then it kicked ya in the arse till 7500,with stock springs,,well this went on all summer,,it loved it,,but one night i got happy doin burnouts,and it developed a rod knock at 8200 rpm,,so i limped home,and i actually ended drivin it all week to work(10 miles each way),before i swapped in another boneyard engine,,so the only thing i see holding back the diesel to rev is not the valvetrain,,its the pump,,or like someone else said,,will it not ignite fast enough at way hi revs??,,besides the stock power peak is at 4800,,so whats the sense of 8k if you have a stock cam??it wont flow up there,,i believe the power peak will remain the same place,just way higher,with turned up pump,boost etc,,deos did on the dyno a few years ago,,was like 115hp at 4600,and 139 ft pounds at 2800,,pretty close to stock peaks,,just way higher on the curve

I found the RPM at which peak power occurs indeed increases with a modded governor on a 1.6lTD.  In fact, I'm curious to see if mine increases even further as I get rid of the binding in the timing advance mechanism and increase my revv limiter even further!  :twisted:  Gotta get my head back on my motor first, though.

[AntonUK]

Hey everyone, I did my governor mod tonight. I replaced the intermediate spring with a washer and also shimmed the main spring so that its half compressed. Hopefully the governor will still kick in but a lot later.

One thing I was surprised at is how much tension is required to move control arm and the force acting on the LDA pin and cone. I’m surprised that the governor pin actually has the ability to fight back against the main spring!

Now that Iv put it all back together very worried how it’s going to work. I tried to start it with some cranking but my battery went flat from using a torch to put the pump back together. I will try in the morning fingers crossed. But when it was cranking it didn’t seem that promising :cry:

I also noticed how much harder you have to push on the throttle when the pin hits the LDA cone. It comes on quite early as well, I hope that I put the throttle lever on the same position as it came off.

Hey fspGTD, did you try the modified timing advance cover you drilled? This is probably going to be next on my list if this governor mod goes successful.

[fspGTD]

Good luck with getting the car started.  I've got a couple ideas that might help: 1. full load screw position - did you re-install it carefully (IE: counting threads) so that it's in the exact same position as it was before being removed?  2.  priming the fuel pump - is necessary if it lost much fuel when the pump was opened up.  Usually when you lift the cover off of the pump with it installed in the car, there is just a pool of diesel fuel sitting there.  If this pool stayed "topped off" when you replaced the cover, I think you won't need to prime it.  But if the fuel level got below the high-pressure inlet port level, you may need to prime the pump - get more fuel inside there somehow.

On the machined timing advance cover - no I have not yet tried it.  You may have heard about my little setback with the 1st gear mis-shift over-rev incident several months ago.  Well the current status is, I just got a new rebuilt head installed onto the block last night, headbolts torqued, cam timed, with manifolds, water necks, and turbo installed...  so it's coming along.

Another setback with my advance cover project that has just recently developed...  I dropped off this cover off to get it anodized with a batch, as well as a bunch of other aluminum parts, and when the parts came back, this cover was missing.  The guy handling the anodize batch is going to check a couple places when he gets home but might have lost it.    Hope it was not left sitting at the bottom of some acid cleaner tank or something!  

[AntonUK]

Thanks for the reply Jake, Iv made another topic on this problem if you havnt already found it...

[malone]

Another setback with my advance cover project that has just recently developed...  I dropped off this cover off to get it anodized with a batch, as well as a bunch of other aluminum parts, and when the parts came back, this cover was missing.  The guy handling the anodize batch is going to check a couple places when he gets home but might have lost it.    Hope it was not left sitting at the bottom of some acid cleaner tank or something!  

I'd love to see this discussion continue. I don't have anything to add at the moment but I'd like to hear updates. A G-Tech plot showing the difference would be nice, too.

[dieselpower]

hey,
i did the timing cover mod a long time back when i first heard about it. personally i didn't see any gains but i had no real way of testing it. if you or a friend or workplace or whatever has a metal lathe...all you have to do is stick it on there and it takes like 2 minutes to do. thats all i did anyway. but like i said..im not sure if it did anything first because i don't have a way of testing it, and second becasue with the govenor mod i did i barely take it above what rpm it used to go, it just gets there quicker. but its gettin warm out now, and i think i figured out a tach setup that might work for me, so im about to modify my govenor again, except this time go all out :twisted:

hope that helps

Mark

[phredde]

A few days ago I installed a washer inside the intermediate spring so it wouldn't compress, didn't experience any difference on the performance so then I also shimmed the main spring a bit and went out for a test drive, revved it up on 1st gear and it wouldn't rev down when I was going to shift to 2nd, went back to the garage and took it apart again and removed the shims so it was back to standard again and then it started to work properly again..
why didn't it rev down?

[fspGTD]

I've got a new timing cover to experiment with (as well as the rest of a disassembled TD pump!   ), and interestingly, it's slightly different than my previous one.  But I've gotten sidetracked trying to get my motor to start more reliably so I haven't gotten a chance to pick back up the timing cover experiments yet.

In theory, the cover should only effect RPMs that are very high at max fuel type setting.  Basically, this might not matter very much for the street, but may make a difference to wring out that last bit of power on a pump with a modded governor.  It is possible I suppose that it won't help at all too - but you need to be able to test this kind of thing with a dyno or RPM-sensing g-tech really, "seat of the pants" is not accurate enough.

Phredde - that is odd that shimming the intermediate spring would not make a difference, I don't understand what would explain that.  In my experience, the difference is so noticeable it would be hard to miss!

Regarding your problem of the RPMs not dropping quickly enough, what's happening is there is too much fuel at "no load".  Are you sure it's the result of the governor shim?  Did you change the position of the full load screw?  I've found that turning in the full load screw too far causes that condition and when it happens I usually end up just backing the full load screw out a bit.