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Engine Specific Info and Questions => IDI Engine => Topic started by: rabbitman on May 19, 2011, 03:44:29 pm
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"Pressure in pump MUST be 43.5 Psi at 1000 RPM engine "
"Pressure at 2000 Rpm -about 75.4 Psi"
Is this info still correct for a euro spec JP code engine? IDK if they had a different curve/advance spring or if it's the same as US spec.
Mine is:
12psi at 1000rpm
25psi at 2000rpm
And I could tell it was acting funny, the cold start knob makes it clack harder even at rpms like 2000-2500rpm.
I'll assume it is 'til I hear different.
Thanks
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I'm trying to bump it up some and find that I can't get it over 30-35 psi at 1000rpm. I tapped the little thing in (way further in than on my rabbit) until it stops changing the pressure and it's not high enough.
Normally the rpms rise as the pressure goes up, well twice now I've tapped it in and suddenly a gush of bubbles go from the filter to the IP and the pressure drops 10-15 psi and the rpm's rise? Doesn't make any sense to me.
Should I try the regulator off my parts pump?
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bubbles go from the filter to the IP
Screams restriction to me...
this was on that other board.
(http://img811.imageshack.us/img811/8999/imgp9968.jpg)
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My guess would be bad seals on the pressure regulator, or stuck vanes in the pump.
One or two stuck vanes in the pump will dramatically reduce the pressure potential of the pump.
Also, do you have the correct "OUT" bolt in the pump when testing? If not, the pressures will never get high enough.
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My guess would be bad seals on the pressure regulator, or stuck vanes in the pump.
One or two stuck vanes in the pump will dramatically reduce the pressure potential of the pump.
Also, do you have the correct "OUT" bolt in the pump when testing? If not, the pressures will never get high enough.
I did change the lower seal and it got me another 5 psi.
I let the IP sit with a ATF/diesel mixture for a couple months so hopefully nothings stuck.
Yes it does have an OUT bolt in it, though I could swap in a different one a see if it changes anything.
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It's acting weird, I could only get about 38psi at 1000 rpm (engine) but if I rev it to 1500-2000 the pressure will shoot up to around 80 really fast, not linear at all.
I had to retard the static timing because it would inject so soon it would try to stall the engine when I drove, now at idle injection is too retarded and it'll smoke blue/miss. But as soon as I put a load on it it'll still clack real bad.
Any info on whether euro diesels had different spec would be greatly appreciated.
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Is the center of the regulator still pushed way down,.. you might have smashed the spring.
I was going to guess bad o-ring on the regulator,.. that connects right to the front of the pump so would explain high internal pressure breaking past the o-ring and pushing fuel back toward the filter.
Maybe you need a different regulator,.. I've done that and gotten better results.
Orrr you could try to find another spring.
I asked the local bosch guy about that regulator spring,.. He said I had to buy a whole regulator.
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Well, the specs came from Hagar on the other diesel forum, and I've always questioned whether or not it's actually supposed to be a linear equation. The numbers he provided are not linear, they're logarithmic. That, and the specs are for PUMP rotation, not engine rotation. Pump rotation will be 1/2 engine rotation. So, does that affect your numbers?
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Well, the specs came from Hagar on the other diesel forum, and I've always questioned whether or not it's actually supposed to be a linear equation. The numbers he provided are not linear, they're logarithmic. That, and the specs are for PUMP rotation, not engine rotation. Pump rotation will be 1/2 engine rotation. So, does that affect your numbers?
If you look at my first post up top, I wrote what hagar wrote which says engine rpm which agrees pretty good with the graph that 745 turbogreasel posted.
I tried my other regulator and the results were not much different. I remember doing this on my rabbit and if I tapped a little too hard the pressure would shoot up to 50-60psi and I'd have to start over, with this one I haven't gotten over 40 yet.
Fatmobile, I start with the center of the regulator flush (zero pressure) and tap it in, it hits 30psi fairly easy but has to go quite a bit more to get 35psi, at 40 the center is about 1/8" down.
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Thanks good to know. I've been looking for the tool to fine-adjust it, but most diesel shops don't have it, or only sell it as part of a master kit that costs close to a grand. No thanks.
I just need that tool, and a good computerized advance tach timing light. I've got the piezo pickup transducer already. I'm kinda pumped to try all this, because my MPG blows (38 in a Rabbit Pickup). If I can get it to 43+, I'd be happy. Rebuilt the pump myself, but obviously, it needs calibration.
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I'm kinda pumped to try all this, because my MPG blows (38 in a Rabbit Pickup). If I can get it to 43+, I'd be happy. Rebuilt the pump myself, but obviously, it needs calibration.
I have to brag a bit. During the winter months I was getting mpg down in the mid 30s but when summer hit it shot up to mid-upper 40s and then I hit my all time best ever, 50.1mpg!!!! I was stoked. I ad about an ounce of lucas injector cleaner every fill up.
Haven't messed with the golf yet today.
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If you are reading and quoting Hagar then you must be familiar with the two pull tests he does to determine a decent pump. 2 and 20 lbs at idle and at running speed. Sounds to me that you may have poor vane pump performance in that it won't get up to pressure until the pump speeds up and throws them out against the internal wall of the pump itself. May be that it needs a teardown and cleaning. You did try the solvent method but could it be due for some pump purge in there as a real good boil out.
I would check to see if the tapping of the regulator hasn't bottomed it out as well. Double check the O ring, was it the fatter thicker one or did you end up slipping on one of the skinny ones.
You have to get this pressure thing set at idle as it makes the timing change once the engine starts to wind up. Dynamic timing is tied to static via pump pressure. And you are correct that it is not linear. I think Hagar had two points on the graph and others came in later and showed him different. And the cold lever advance does not work much above the idle. 2.5 degrees advance I think is what it gives when cold but once the RPMs go up so does the internal pump pressure and the advance is greater than what the lever provides.
Total advance is 12 degrees? That is controlled somewhat by the spring accessible from the front cover. Slip a shim out of there and your advance starts early, and even earlier with the proper colored spring. Green is least resistive, I have two pumps and I am lucky enough to have two springs that are on the low end of resistance so I am playing with them and the thickness of shims to get me more advance earlier so when cruising at 50 I have the advance of what I used to get at 65. That allows me to keep my foot off the gas more and that gets me, to quote hagar, Smileage.
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Yeah I've read all that stuff, the problem with the pull test is that this IP has an idle up feature that works with the advance so as I pull the handle it idles up making it easier to pull.
I also used a pressure guage which is far more accurate than the the pull test.
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And you are correct that it is not linear.
Er, I was suprised how linear mine were, can't remember the results, but they are someplace on the forum if you guys want to look.
If you are worried about the precision adjustment with the hammer, you are right to be, it is ridiculously sensitive. You can use a narrow bolt as a drift, with a nut set to restrict how far the pin can be moved.
With designers cutting NOx, do later diesel engines have reduced rises in transfer pressure? so would an earlier pressure regulator a good thing? For more power, mpg & NOx?
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As you can see from the results, the response plotted was near as doesn't matter; linear within the normal working range. Springs tend to give linear responses within normal ranges, so it makes sense.
Against this ideal could be that the escape[feedback] orifice is circular and so possibly non linear.
Hagar was wrong with his extrapolation. Also note his figures were based on the yellow dot pump, a somewhat unique item, I believe that came about because of govt diesel blend rules, emissions, and Bosch experimental response.
This graph is the corrected version,and I found Hagar's numbers dropped down a little from earlier graphs, but still steeper than the other measurements for the other pumps.
Note how 'my' and Levi's mirror the gradient 'average' values I extracted from SAE.
I'd like to add that increasing the pump pressure isn't the panacea that people think.
REasons:
1) Pump pressure response is still linear for lower pressures.
2)What matters is pump advance response to changes in RPM. Again as advance is a spring, it is linear wrt pressure, so as long as it starts compressing with rpm increases, it will do as you want.
3)Look at 'My' pump results; the repaired values now mean that at 710 to 740 idle speed, [where I operate] the advance lever only advances between 1 and 2 degrees crank. This means that I am wasting 3 to 4 degrees advance that could be used at the top end [not that I ever go there ;D. ]
4) Thus all that the addition pressure does is put additional strain on the pump seals....
So I may return to lower pump pressures...
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There seems to be various numbers thrown around as to what the internal IP pressure should be. Does anyone have the official Bosch spec for it?
So far, I have a gauge hooked up to the out bolt pedestal and I have 2 regulator bolts to play with. They both measured 30 psi at idle of around 1000 rpm. I pulled both regulator bolts out and replaced the o-rings on both of them and installed only one so far and noted the pressure is now 20 psi (from re-newing the o-rings). I tapped on the regulator bolt while the engine is idling while watching the gauge and got it up to 50 psi at 1000 rpm. I have to take on for a road test.
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There seems to be various numbers thrown around as to what the internal IP pressure should be. Does anyone have the official Bosch spec for it?
So far, I have a gauge hooked up to the out bolt pedestal and I have 2 regulator bolts to play with. They both measured 30 psi at idle of around 1000 rpm. I pulled both regulator bolts out and replaced the o-rings on both of them and installed only one so far and noted the pressure is now 20 psi (from re-newing the o-rings). I tapped on the regulator bolt while the engine is idling while watching the gauge and got it up to 50 psi at 1000 rpm. I have to take on for a road test.
Who's throwing numbers around? Never seen Bosch numbers. They are hidden in their microfische and unobtainium.
Apart from Hagar's claimed figures for the 107A, the most accurate, and based on 23 TD pumps averaged, is the scatter diagram fig 46, on the SAE paper #820441 about the 1.6TD design.
My figures are the best anywhere in the public domain. Period!
I averaged the scatter diagram to create a reference plot to compare and contrast, Hagar's corrected figures, 'My pump' and someone called Levi's... Do a search...
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Forgot about this thread, I thought I had something about this already.
Tried starting again last night, temp slightly below freezing. It was a no go, fired quite a bit but couldn't get spinning.......even blew some perfect smoke rings haha ;D. Battery's charging now.
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Thanks good to know. I've been looking for the tool to fine-adjust it, but most diesel shops don't have it, or only sell it as part of a master kit that costs close to a grand. No thanks.
I just need that tool, and a good computerized advance tach timing light. I've got the piezo pickup transducer already. I'm kinda pumped to try all this, because my MPG blows (38 in a Rabbit Pickup). If I can get it to 43+, I'd be happy. Rebuilt the pump myself, but obviously, it needs calibration.
There's a lip at the bottom of the regulator bolt's head where you can make a tool to hook onto that lip like a "puller", by advancing the puller screw. you can fine adjust the pressure. However, with a long punch and a hammer and watching the gauge while the engine is idling tapping on the center of the bolt, you have pretty good control increasing the pressure by tapping with a hammer. At least that was my expereince using a hammer and and 10" extension on a 3/8 drive allen head driver bit as the punch.
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Does any one remember this info and would it help?
http://www.vwdiesel.net/forum/index.php?topic=19692.0 (http://www.vwdiesel.net/forum/index.php?topic=19692.0).
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Thanks good to know. I've been looking for the tool to fine-adjust it, but most diesel shops don't have it, or only sell it as part of a master kit that costs close to a grand. No thanks.
I just need that tool, and a good computerized advance tach timing light. I've got the piezo pickup transducer already. I'm kinda pumped to try all this, because my MPG blows (38 in a Rabbit Pickup). If I can get it to 43+, I'd be happy. Rebuilt the pump myself, but obviously, it needs calibration.
There's a lip at the bottom of the regulator bolt's head where you can make a tool to hook onto that lip like a "puller", by advancing the puller screw. you can fine adjust the pressure. However, with a long punch and a hammer and watching the gauge while the engine is idling tapping on the center of the bolt, you have pretty good control increasing the pressure by tapping with a hammer. At least that was my expereince using a hammer and and 10" extension on a 3/8 drive allen head driver bit as the punch.
That seems a good method.
Possibly a better one is simply a M5 or M6 bolt with a nut on it as a depth gauge/depth stop, when used as a punch...
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Does any one remember this info and would it help?
http://www.vwdiesel.net/forum/index.php?topic=19692.0 (http://www.vwdiesel.net/forum/index.php?topic=19692.0).
Funny thing that, I already had it rotated on my screen earlier on ACDSEE.
Not easy to decypher.
How does the measured internal pressure have a range of values and not a single figure for each rpm reading? Or is this not a client's particular results, but the general spec? :-\ I'll give it a good read again.
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I called a diesel injection shop and asked what the internal pump pressure should be for my pump 0 460 484 027 and was given these numbers:
5 to 5.5 bars (72.5 to 79.7 psi) @ 2500 RPM (engine ). This translates to 32 psi at 1000 rpm (assuming pressure is linear), which was what my regulator was at before I started messing with it!
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The data on the spec sheet for the pump pressure nestles directly below the SAE real pump averages. Smack on where I changed my pressures to.
Note the impossibility of following Hagar's 107A values, by his 'Desciples'
The SAE paper dates from a little after 1981.
Funny how Bosch specs for this pump dropped the internal pressure a few psi, compared to the SAE average of 23 contemporary pumps.
Here is my graph again for reference:
(http://img811.imageshack.us/img811/8999/imgp9968.jpg) (http://imageshack.us/photo/my-images/811/imgp9968.jpg/)
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Looking at these idle and 2500 RPM numbers makes me think mine might be a tad high and that may explain the little bit o marble sound I have at just off idle. I have gone to watching the psi of the IP gauge as kind of a shift light. Mine doesn't have one but it seems that when i hit 75 lbs of pressure the shift is just about right on the level surface. Going to run it that way for a bit and see what the mileage does.
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Note that Levi was 'on the money' with his second iteration, but went on to excessive pressures in a mistaken belief [like many] that the 107A pump was the standard spec to aim for.
Also note my pump was right down the bottom of the graph when I first checked it, yet it operated linearly. With the right soft spring we could all operate down there and the leaking pump seals would be a thing of the past...
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I did notice that my engine ran fine with a bit of advance with the gauge showing 10 lbs. I think on revving it up the pressure only topped out at 25. So yes it will run but I wonder how well? Yours pull OK under a hard load? Mileage acceptable?
I think the pressure could be a little less than the oft quoted 43 lbs at idle but just how much less we shall see. I knocked mine back and am watching for changes to the overall performance. Mileage is one thing, drivability is another. I can't be in everyone's way getting 60 MPG.
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The data on the spec sheet for the pump pressure nestles directly below the SAE real pump averages. Smack on where I changed my pressures to.
Note the impossibility of following Hagar's 107A values, by his 'Desciples'
The SAE paper dates from a little after 1981.
Funny how Bosch specs for this pump dropped the internal pressure a few psi, compared to the SAE average of 23 contemporary pumps.
Here is my graph again for reference:
(http://img811.imageshack.us/img811/8999/imgp9968.jpg) (http://imageshack.us/photo/my-images/811/imgp9968.jpg/)
Is this the pump spec sheet (below pic) you're referring to? If I'm understanding correctly, that is a spec for settings of a Bosch test stand for one particular injection pump. Does anyone know which pump that spec sheet is for? Internal pump pressure is not the same on all VE pumps from what I was told.
(http://i232.photobucket.com/albums/ee10/joshmarstall/PICT0902.jpg)
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My figures are the best anywhere in the public domain. Period![/color]
Mark I DO belive you.
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My figures are the best anywhere in the public domain. Period![/color]
Mark I DO belive you.
:o
I've just chased those numbers on that Bosch paper literally all round Eastern Europe, Europe and back to America, where I found they translate into a 1984 1.6TD ... Jetta. Thus I was correct, Bosch did lower the internal pressure of the pump from the first 1.6TD's
This shows the truth being, that Bosch, just like lots of other Co's were experimenting and learning as they went along...
A big question:
How long does it take for a pump to fill a piston chamber, and does vaccuum play more part than pressure?
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so how would you get the pressure curve of the yellow dot? you would need the regulator from it with the matching advance spring?
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Finally put some miles on familair roads with the higher internal pump pressure. At 2500 rpm, it's at 80 psi, 5 psi above spec for my pump. I can say that the car has more power throughout the rpm range. Hills that I used to have trouble maintaining speed in 5th, I now have no problems and can actually accelerate up them.
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Finally put some miles on familair roads with the higher internal pump pressure. At 2500 rpm, it's at 80 psi, 5 psi above spec for my pump. I can say that the car has more power throughout the rpm range. Hills that I used to have trouble maintaining speed in 5th, I now have no problems and can actually accelerate up them.
Just the same as advancing your pump slightly, is it not?
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so how would you get the pressure curve of the yellow dot? you would need the regulator from it with the matching advance spring?
Basically yes.
Maybe a softer than yellowdotspring would work too with a standard regulator spring?
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Finally put some miles on familair roads with the higher internal pump pressure. At 2500 rpm, it's at 80 psi, 5 psi above spec for my pump. I can say that the car has more power throughout the rpm range. Hills that I used to have trouble maintaining speed in 5th, I now have no problems and can actually accelerate up them.
Just the same as advancing your pump slightly, is it not?
IDK. My pump timing is set at 1.0 mm but have not played with it yet. Wouldn't starting be different?
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Mark and ECO92, Kicking back the timing to a more retarded condition and upping the internal pressure is what gives my ride the miles per gallon and the performance I have. Seems that it starts just fine on cooler morings, 40F is about as cold as I get. Running the gauge allows me to see the difference between the cruise at 65 mph in fourth versus fifth. In 4th I am right up at 75 psi and in 5th I drop down to about 62.5. That is a big difference in how the advance is treated. I can really move once the pressure exceeds say 65 but it lugs a lot below that. So my thought is to run more pressure and let it do the advance instead of trying to get it there with the initial timing.
By keeping the initial time a little retarded I think it helps keep the knock down at mid speed cruising like 25 to 40 mph.
Going to go with it a while and see where the mileage comes out.
ECO92, your performance at the higher RPMs wouldn't be do to the fuel mix screw adjustment being in a half turn more than normal is it?
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I don't really know since my fuel screw has been messed with. But I can say that it is aprox at the same setting as another untouched pump and I am not getting any smoke when I floor the pedal. My static timing is set at 1.0 mm currently. I will drive it for a few tanks with the current setting and see if MPG improves, then adjust the (static) timing down/up and see what it does MPG and performance wise.
Pressure is a function of rpm. You are seeing higher pressure in 4th because your engine is at a higher rpm in 4th at 65 mph than 5th at 65 mph.
Mark and ECO92, Kicking back the timing to a more retarded condition and upping the internal pressure is what gives my ride the miles per gallon and the performance I have. Seems that it starts just fine on cooler morings, 40F is about as cold as I get. Running the gauge allows me to see the difference between the cruise at 65 mph in fourth versus fifth. In 4th I am right up at 75 psi and in 5th I drop down to about 62.5. That is a big difference in how the advance is treated. I can really move once the pressure exceeds say 65 but it lugs a lot below that. So my thought is to run more pressure and let it do the advance instead of trying to get it there with the initial timing.
By keeping the initial time a little retarded I think it helps keep the knock down at mid speed cruising like 25 to 40 mph.
Going to go with it a while and see where the mileage comes out.
ECO92, your performance at the higher RPMs wouldn't be do to the fuel mix screw adjustment being in a half turn more than normal is it?
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Pressure is a function of rpm. You are seeing higher pressure in 4th because your engine is at a higher rpm in 4th at 65 mph than 5th at 65 mph.
Figured that, what I see is that once I get that little bit over 65 psi it really takes off. I don't have a tach so I would have to figure it out with the speedo calculator to see what RPM I am running at in those gears and speeds with the 155's on now.
Hunting an exhaust header over the weekend. Price is being negotiated, may be breathing easier next trip up and back.
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Pressure is a function of rpm. You are seeing higher pressure in 4th because your engine is at a higher rpm in 4th at 65 mph than 5th at 65 mph.
Figured that, what I see is that once I get that little bit over 65 psi it really takes off. I don't have a tach so I would have to figure it out with the speedo calculator to see what RPM I am running at in those gears and speeds with the 155's on now.
Hunting an exhaust header over the weekend. Price is being negotiated, may be breathing easier next trip up and back.
told you i had one that i would almost give you..
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But I gotta drive all the way up north to get it. This one is new in box and local. But I didn't forget your offer. It may end up costing the same between fuel, and time. I will be taking time off from work in the next month and I may just have to arrange something with you if this fails to produce any good results. Thanks.
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But I gotta drive all the way up north to get it. This one is new in box and local. But I didn't forget your offer. It may end up costing the same between fuel, and time. I will be taking time off from work in the next month and I may just have to arrange something with you if this fails to produce any good results. Thanks.
astoria isnt that far from portland.. if you drive 26, your less than 25 miles from me at times..
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PM Time!
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I thought I'd update this thread since I've upped the internal IP pressure to spec and accumulated some miles. It's been running great! More power, less smoke. I used to see smoke at night in the rear view mirrow from headlights behind when i stomp on it. This is no longer the case, it is burning much cleaner. A slight leak just developed in the top IP cover seal. Luckily, it's and easy one and can be done without pulling the IP.
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So was your guess of 32psi @ 1,000 rpm, correct?
Have you been tracking your milage, and if so, how does it compare to "before"?
-Todd
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So was your guess of 32psi @ 1,000 rpm, correct?
Have you been tracking your milage, and if so, how does it compare to "before"?
-Todd
I didn't guess. I got the spec from a Bosch diesel shop. 32 psi @ 1000 is not correct BTW for my pump. I have not been tracking my mileage. I get 550 to 600 miles per tank.
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I called a diesel injection shop and asked what the internal pump pressure should be for my pump 0 460 484 027 and was given these numbers:
5 to 5.5 bars (72.5 to 79.7 psi) @ 2500 RPM (engine ). This translates to 32 psi at 1000 rpm (assuming pressure is linear), which was what my regulator was at before I started messing with it!
I understand that you got the spec @ 2500rpm, but you never mentioned a spec @ 1000rpm.
-Todd