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Engine Specific Info and Questions => IDI Engine => Topic started by: Bean on March 15, 2007, 08:05:37 am
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Okay, I have a 1.6D N/A, and was browsing through these forums for power mods.
All very clear and understood almost everything - except one thing...
How to adjust idle PROPERLY. As far as I can see, there are a few ways to do it. However, only one way seems to apply to my pump.
I read on the "Make your 1.9TD a faster car" thread that the idle should be adjusted with the service idle screw - in my case, this screw is in fact a 7mm hex-headed bolt with a spring round the top of it, which moves downwards when the cold start is pulled out.
If I unscrew this, it makes no difference and just feels as if I'm removing it. I can only tighten it up to a point, were it's just 'screwed in'. It doesn't seem to adjust anything.
The other place I can see to adjust something is two screws on the back which seem to be linked to a see-saw mechanism. What does this control? Would I need to loosen one to screw the other in?
And finally - what's labelled as the "residual fuel screw" in the "make your 1.9TD faster" thread. This was the one I adjusted to lower my idle after increasing fuel, and it worked up to a point but it still needs to go a tad lower.
Can anyone clear up where the idle is supposed to be adjusted, and why my "service idle screw" seems to do nothing (and isn't even a screw)?
Also, I'm doing the governor mod this weekend and read that you're only supposed to do the "max rpm" mod on it if it's an N/A, and not the part load mod. What does this entail? Just pre-loading the main spring and leaving the part load/intermediate spring in tact?
Many thanks,
Sean.
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Okay, I have a 1.6D N/A, and was browsing through these forums for power mods.
All very clear and understood almost everything - except one thing...
How to adjust idle PROPERLY. As far as I can see, there are a few ways to do it. However, only one way seems to apply to my pump.
I read on the "Make your 1.9TD a faster car" thread that the idle should be adjusted with the service idle screw - in my case, this screw is in fact a 7mm hex-headed bolt with a spring round the top of it, which moves downwards when the cold start is pulled out.
If I unscrew this, it makes no difference and just feels as if I'm removing it. I can only tighten it up to a point, were it's just 'screwed in'. It doesn't seem to adjust anything.
The other place I can see to adjust something is two screws on the back which seem to be linked to a see-saw mechanism. What does this control? Would I need to loosen one to screw the other in?
And finally - what's labelled as the "residual fuel screw" in the "make your 1.9TD faster" thread. This was the one I adjusted to lower my idle after increasing fuel, and it worked up to a point but it still needs to go a tad lower.
Can anyone clear up where the idle is supposed to be adjusted, and why my "service idle screw" seems to do nothing (and isn't even a screw)?
Also, I'm doing the governor mod this weekend and read that you're only supposed to do the "max rpm" mod on it if it's an N/A, and not the part load mod. What does this entail? Just pre-loading the main spring and leaving the part load/intermediate spring in tact?
Many thanks,
Sean.
you can play around a bit with the seesaw mechanism... i believe the passenger side one is for the cold start idle boost? but i could be wrong... i just can't remember.
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They can't be for seperate things can they? (The two screws that control the see-saw thing). Surely it just controls one thing, and you have to adjust both screws accordingly?
Which way do I want to adjust it to lower my idle?
Also - I'm going to be running 50/50 veg oil/diesel as of the weekend, do I need to make any adjustments to the pump to accomodate it? Advance timing or anything?
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Thanks guys, thats cleared up a couple of things.
I can't see a residual fuel screw though? Anyone got a pic of one?
It was the idle stop screw that I adjusted then. That worked well, but when the engine is warm it idles higher than it should be and when unscrewing the idle stop screw it doesn't make a difference anymore (I don't think - I'll check again tomorrow.)
Had exhaust problems earlier so I just cut most of the back section off :lol:
Now it sounds like a tractor. No worries though, I'm getting a custom exhaust on saturday with the stack going through the bed :twisted:
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It's also known as the "fuel" screw and is the first large picture on the second page of the "make your 1.9TD faster" thread.
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Ahh right, yeah I know where that is. That's what I adjusted in the first place to increase the fuel (obviously).
Thanks for clearing it up :)
So is there a point where adjusting the idle stop makes no difference anymore due to too much fuel coming in? It's not revving high or running away at all, it's just a little above where it should be when the engine's warm.
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hey vince, that see-saw device has no connection to the cold start handle on most AAZ's. it is conencted to the vacuum pot to the electric high idle solenoid. You can use it ot set your high idle when cold. IT is automatic in the aaz's through a solenoid
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True dat... mechanical fast idle linked to the cold start handle much more common pre-AAZ.
Having said that, most AAZ pumps have the socket on the fast idle cam for the required pushrod, and my pump came with the full cold start fast idle...no vacuum pot.
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So stoked on life right now because Vince said "True dat".
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Hey, I'm hip. I know all about you youngsters, with your Facetubes and your Youbooks.
Now get off my lawn. ;)
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Vince. If I am ever in Edmonton. I will rev my vw in front on your house and do donuts on your lawn.
True Dat
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Here's my opinion on the matter.
That see-saw thing on the back of the pump controls both the fast idle and normal idle. When it is rocked one way it is fast idle, and rocking it the other way is your normal idle. Fast idle is adjusted with the screw closest to the timing belt. Normal idle is the other one. TYPICALLY you can and should just rotate the 7mm nut on the end of the rod to adjust your idle. However once you've fiddled with the max fuel screw there may not be enough range on the rod. This is when you would need to adjust the screw farther back from the drive end.
The residual fuel screw does not usually have an effect on idle. It controls how quickly your RPMs drop. If it is screwed in past a certain point it will have an effect on the idle. Ideally you shouldn't be playing with this screw unless you've fiddled with the max fuel screw.
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Please put this in FAQ.
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Please put this in FAQ.
Done. It's worth noting that older pumps that don't have the fast idle are adjusted by using the throttle stop screw.
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Yeah, to make the FAQ-worthy it really should have some pictures... I'll see what I can dig up on the couple different pump configs I've got in the shop.
We should also change the title... since it won't naturally tell folks what's inside. ;)
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I see this is an old post but I didn't find one with more info to bump.
I'm playing with my first pump that has the idle bump connected to the cold start lever.
This is a pump I pulled off a car at the salvage yard.
It was missing the spring on the end of the governor, I think it's called the idle spring.
I grabbed one from another pump and put it on the one in the picture.
(http://img585.imageshack.us/img585/8250/injectionpumpidlebumpgo.jpg) (http://img585.imageshack.us/i/injectionpumpidlebumpgo.jpg/)
So my first question is are these supposed to have an idle spring?
... because inside:
(http://img9.imageshack.us/img9/3770/injectionpumpidlebumpsp.jpg) (http://img9.imageshack.us/i/injectionpumpidlebumpsp.jpg/)
where the screwdriver is pointing,... there is no spring.
You can see the hook the small idle-bump spring connects to, the one that gets pulled when the see-saw idle is adjusted.
There has always been a small spring between that lever,
which below holds the ball which fits in the collar,
and the lever the accelerator springs hold onto,
which is moved with the residual fuel screw.
I'm having trouble adjusting everything for more power and a low idle.
I can get it to run good but can't get any black smoke or power anywhere above midrange.
Usually I'd turn in the max fuel screw and back out the idle.
The idle is adusted by the 7mm cap nut on the rod going down to the cold start lever.
By the way when you turn the cap; the whole rod is supposed to spin.
I'm not sure what threads into what, if it threads into the plastic at the base.
Idle also limited by one of the lock-nutted screws above the see-saw
and on the back of mine there is a torx bolt change the change the relationship between see-saw and the cold start rod by allowing it to slide in the adjuster slot.
This pump's adjustment change more than just the max fuel and idle.
I swear some times it misses like the timing is retarded when revving.
A few adjustments and it'll smooth back out,.. but I still can't get black smoke or enough power.
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Looks like you're missing the middle (intermediate) spring
(http://i1183.photobucket.com/albums/x480/Ecodiesel92/IMG_20120401_154427.jpg)
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Yeah, that's my way of doing a governor mod.
I should have mentioned it but didn't want to get off topic.
I removed that spring and put a few washers in it's place.
If anything it should make more smoke and power with it so that's not why I'm low on power and smoke.
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and another spring missing on the left end....?
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Your way does mod the governor, but it is harder to drive. It will not increase high RPM fueling either so that maybe why you cannot get black smoke or enough power.
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and another spring missing on the left end....?
x2, now that you mention it.
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and another spring missing on the left end....?
I think that's just the peogot spring setup.
I haven't seen an added spring on the very end on a VW.
Unless you are saying the idle-bump pumps are definately supposed to have another spring on the end.
... the idle spring was missing.
"Your way does mod the governor, but it is harder to drive. It will not increase high RPM fueling either so that maybe why you cannot get black smoke or enough power"
I understand this is a mild gov-mod compared to some but it has always given me good power through the range
with none of the idle problems I've seen attributed to this setup,..
and it has always given me enough smoke with the other pumps I have it on.
Including the 109AG I just took off, I could belch a big cloud then pull the VNT turbo lever and take off.
I can't even get much black smoke off boost with this pump. A puff then it turns whiteish.
If this didn't have a idle-bump I'd lower the idle and turn the max fuel screw in.
so Plan A: I'll try lowering the idle as far as I can,
using the torx screw on the back,
the 7mm cap-nut on top of the rod going to the cold start,
the residual fuel screw.
and the low idle stop for the see-saw
Then I'll set the accel arm on the spline that works best with the max fuel screw.
I think this is going to cause it to stumble on acceleration.
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and another spring missing on the left end....?
I think that's just the peogot spring setup.
I haven't seen an added spring on the very end on a VW.
Unless you are saying the idle-bump pumps are definately supposed to have another spring on the end.
... the idle spring was missing.
.. .......
are we talking about the governor spring or the other spring? the pic I posted the left 1 is a VW the right 1 is a Peugeot governor and they both have a spring on the left.
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In the pic the peogot pump has a spring to the left of the idle spring,
I don't know what to call it because it's not listed as being on any of the VW pumps.
Your picture contradicts what you are saying, the VW spring setup has no spring to the left of the idle spring.
Well, I'll see if can figure out how to adjust this pump.
If I do I'll post it.
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In the pic the peogot pump has a spring to the left of the idle spring,
I don't know what to call it because it's not listed as being on any of the VW pumps.
Thy are both an idle spring.
I can't even get much black smoke off boost with this pump. A puff then it turns whiteish.
If the smoke is turning white as RPM's pick up I would suspect your timing is way to far advanced, or your pumps pressure is way too high causing too much advance.
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I would take the intermediate shim out and put the spring back in and see if that helps. Shimming that area doesn't fare well, and will not give you any more high rpm fuel.
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Fatmobile, your idle spring is the one that is the extension spring that's hooked to the seesaw lever and hooks to the control lever assembly. Removing and shimming the intermediate spring will raise the high rpm fueling the same amount as leaving the intermediate spring in place and shimming the main spring. The difference between the two actions is that removing and shimming the intermediate spring area more significantly changes the feel of the first part of the pedal. It makes the first part of the pedal more sensitive and the upper part of the pedal less effective. There's nothing wrong with either way provided you like the way the pedal feels.
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When I did the intermediate spring it wouldn't "blow black smoke" This was before I had EGT gauge and it isn't a real good measure I know. I would think that the main fuel spring would still compress the same ammount and not fuel fully. I thought since the IM spring was on the other side of that assembly and not in contact with the main spring at all it would have 0 input on what the main spring did? Basically, shimming the IM spring would just take up the spring space and make it not cut the above idle RPM fuel going right to running strictly off the main spring? How would you discribe it, I am all for learning.
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In the pic the peogot pump has a spring to the left of the idle spring,
I don't know what to call it because it's not listed as being on any of the VW pumps.
Your picture contradicts what you are saying, the VW spring setup has no spring to the left of the idle spring.
Well, I'll see if can figure out how to adjust this pump.
If I do I'll post it.
OK I see what you're saying now. The spring on the left (to the left of the idle spring) is visible only in the Peugeot governor on the right in the pic above, not in the VW governor.
I remember the Peugeot governor is longer than the VW governor when I measured them last year. Dug up this old pic which shows the different lengths. That 4th spring is barely visible in the Peugeot governor (most of it seated in and hidden by a cup). That's the lightest of the 4 springs. My guess is it gives a very sensitive off idle throttle?
(http://i1183.photobucket.com/albums/x480/Ecodiesel92/IMG_20120401_132321_zpsf3292098.jpg)
I found an old pic which shows
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Fatmobile, your idle spring is the one that is the extension spring that's hooked to the seesaw lever and hooks to the control lever assembly. Removing and shimming the intermediate spring will raise the high rpm fueling the same amount as leaving the intermediate spring in place and shimming the main spring. The difference between the two actions is that removing and shimming the intermediate spring area more significantly changes the feel of the first part of the pedal. It makes the first part of the pedal more sensitive and the upper part of the pedal less effective. There's nothing wrong with either way provided you like the way the pedal feels.
What does that idle screw thread into?
I see the whole rod turning down to the lower spring.
Does it thread into the plastic piece at the bottom? Or is there a stud coming from the plastic that it threads onto?
How many threads/turns does it have before something comes apart and a spring flies?
And there is an adjustable stop the see-saw rests against that can be screwed out. My plan is to have that backed all the way out.
I don't throw my intermediate springs away. I'll try the solid main with an IM spring some time but I like the feel of this gov mod for daily driving.
If the smoke is turning white as RPM's pick up I would suspect your timing is way to far advanced, or your pumps pressure is way too high causing too much advance.
Thanks 8v, I can check both of those. Right now it's timed by ear and effect the cold start has on it. It stumbles on startup until I pull the cold start.
Internal pump pressure is something I haven't checked yet and it makes sense to see how the timing curve is working on this.
I'll have to bust out the diesel pulse timing light/tach and internal pressure gauge.
I keep thinking it has something to do with the residual fuel screw and how it relates to the idle adjustment.
Someone said the residual fuel screw shouldn't effect idle much but it does.
I suppose it could be set up so at idle the idle spring pulls it's lever away from the one the governor spring connects to.
and the governor spring pulls them solidly together (no spring) when accelerating.
If this is the plan then lowering the idle will let that lever rest against the one the governor spring connects to,.. at idle. They basically become the same lever.
Soo I'm still in theory about this pump's adjustments but it's really cold out these last couple days, not so bad until coupled with high winds.
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I feel you, -28c before windchill here right now... B.S! LMAO
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My experience has been that white/grey smoke at higher rpm is from retarded timing compounded by injector lag.
Over-advance has gotten me increased cranking, more nailing and poor fuel economy, but not much smoke.
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If you are having adjustment issues with the idle being controlled by the main fuel screw you may need to index the arm on the splined shaft.
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If the smoke is turning white as RPM's pick up I would suspect your timing is way to far advanced, or your pumps pressure is way too high causing too much advance.
IIRC, another member had white smoke at high rpm caused by a binding roller ring that defeated the dynamic advance.
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i have also heard of white smoke at high rpms caused by valves sticking open from too high of oil pressure or too much back pressure (high exhaust manifold pressure). on hydro lifters only.
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It's a mechanical head.
This car ran good before the pump swap.
I heard these pumps have more power and give better fuel mileage. Hoping for an upgrade.
The TD pump with this idle bump, on my '84 with the 1.7TD, works great. I never touched it.
If you are having adjustment issues with the idle being controlled by the main fuel screw you may need to index the arm on the splined shaft.
I have been changing the position of the arm on the splines.
I tried putting it back on the same as it was but the governor spring was pulling too hard, RPMs climbed. I had to back the max fuel screw out too far.
I could look through the OUT hole and see the idle spring was already pulled tight and moving the lever moved nothing.
As it's set now I can see the idle spring compress when the arm is moved.
The line on the splined shaft isn't pointing at one of the 3 lines on the arm. I haven't seen that before, other than in a pic 8v showed of his pump. Same kind of pump.
Yeah, I'm going to have to get the tools out and see what the timing curve looks like before I can figure this out.
White smoke can also be caused by air in the fuel but I haven't been seeing any of that.
It is hard to prime after opening it up. I have to suck fuel through the pump and pull all of the air out. It won't seem to pull fuel on it's own until all air is removed.
so maybe the fuel pressure regulator is set too low and air is getting pushed back to the front of the pump once inside.
It runs smoothly once it does start.
One thing I didn't check was if the accelerator arm is making it all the way to it's stop when floored.
The whiteish smoke isn't just at high RPMs, midrange too.
Seems like I read it's a sign of an improperly set residual fuel screw.
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Pressure regulator or vane pump could be of issue.
I don't think the residual pressure screw changes mid range smoke. If it is out of adjustment, the car will buck when trying to cruise with very light accelerator pressure.
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I feel you, -28c before windchill here right now... B.S! LMAO
I don't think he wants you to feel him. ;D