internal injection pump pressure

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Fatmobile
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internal injection pump pressure

Post by Fatmobile »

I started reading Hagar's tuning thread and thought it would be a good idea to grab some gems from it and give them their own thread.
Internal pump pressure is a very important part of what he is teaching us so it seems like a great place to start.
From Hagar's hillbilly tuning post, 2nd page near the bottom:
"Pressure in pump MUST be 43.5 Psi at 1000 RPM engine "
"Pressure at 2000 Rpm -about 75.4 Psi"
Internal pump pressure will determine how much fuel flows through the "OUT" bolt on top of the pump. From Hagar's page #3:
"If the IP flow is less than about 25 litres per hour at idle ---you will never get to really great Smileage. "
An hour seems like a long test so values for shorter times will be listed when I (or someone else) find them and can post them here.
On page 4 Hagar notes:
.SAGA : ---- somehow a TYPO sneaked in here somewhere ---so here are the numbers for you ALL one more time.
Numbers are from BOSCH and given for the 107 A pumps.

PUMP RPM first. 500 RPM 3 bar 750 RPM 4.1 bar 1000 RPM 5.2 bar.

so we can plot a line to 2000 RPM say 10.4 bar --EH ? ---ergo at 4000 RPM ENGINE ---about 150 PSIG
Last edited by Fatmobile on Sun Aug 19, 2007 11:46 pm, edited 1 time in total.
libbybapa
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Post by libbybapa »

0.417L per minute. What's that in US measure?

Hagar's setup:
Image

My setup:
Image

I used a pedestal from a n/a diesel and drilled and tapped a standard compression fitting in order to use a mechanical oil pressure gauge. The pedestals are readily available. Two stacked together would allow easy fitting to a TD pump. One works fine for a n/a pump.

Andrew
dieselsnowmobile
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Post by dieselsnowmobile »

1 liter = 1.0566882 US quart

About .440287 quart/min, or .11 gallon/min.
'89 1.6L NA Diesel Jetta (521,000 mi) w/ Rabbit Engine (230,000s mi)
'91 1.6L NA Diesel Jetta (1500 hrs since I have owned it)
'86 2.1L Gas Vanagon 7 passenger (123,000 mi)

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floydr
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Post by floydr »

here is a page with metric to all sort of different messuremet standards conversions. http://www.sciencemadesimple.com/conversions.html
Since I would imagine most peopl have measuring cups ( don't use your wifes good ones go out and get some cheap ones 2 or 3 cups in size)I converted it to cups 1.76 cups (US, liquid). so aprox. 14 fluid oz.

later
Mark
1981 VWDasher Diesel
WVO conversion sept 27,2006
Single tank conversion
12v injector line heaters, coolant fuel filter heater, and 12v fuel line heater
dieselsnowmobile
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Post by dieselsnowmobile »

Well, you could just use one of these

Image

and just adapt it to the small fuel line. Not very precise and pretty expensive, $200. It would sure beat getting yelled at by your wife and keep the diesel taste out of your food.

Ok, I am joking a bit. After doing some searching I found this one with its face down in the picture, you will have to look at the manual to see the read out.

http://transfer.tuthill.com/Products/Fl ... /index.asp

Or you can select from their wider range of meters

http://transfer.tuthill.com/Products/Fl ... /index.asp

These might be more reasonable if one is really interested.
'89 1.6L NA Diesel Jetta (521,000 mi) w/ Rabbit Engine (230,000s mi)
'91 1.6L NA Diesel Jetta (1500 hrs since I have owned it)
'86 2.1L Gas Vanagon 7 passenger (123,000 mi)

YouTube Videos
stopping
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Post by stopping »

Yes Fatmobile... good idea on starting this thread.

I don't have smaller images yet sorry for the size of these. If they too big please let me know.

I made a IP tester out of an old out bolt (my old N/A 1.6 shares the same bolt number). It has a hose so I can drive with it in place not rattle the living daylights out the gauge.

Oh the gauge is wrong, I know, it's just for the photo.

http://photos1.blogger.com/blogger/3322 ... Ptool2.jpg

http://photos1.blogger.com/blogger/3322 ... IPtool.jpg
hagar
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I.P. internal pressure.

Post by hagar »

Fatmobile and ALL : I am pleased beyond words to see that you guys pay attention. ----and I do like Andrew in Flagstaff AZ version. ( I am still trying to get to the bank --to send him a money order for his Guitar plucking CD --I think it will happen) --that guy can TUNE more than a Rabbit.

Did hagar test for a full hour ? ---think. ---I intended to tell you guys , the incredible flow of fuel while driving --it all goes through the filter and so on --- BOSCH claims that it is part of design for COOLING pump.----flow increases as pressure increases ---so ? --well that is a lot of gallons ---on the way to gramp's Turkey dinner , for some Rabbits.--EH ?.

The flyballs trash around in fuel at almost engine speed --that makes for heat ---If we recirculate fuel in pump without return to tank or filter --the heat will destroy pump.

hagar.
libbybapa
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Post by libbybapa »

Why is internal pump pressure important?

It is important because it controls the dynamic timing advance and if the dynamic timing advance is incorrect then fuel economy and performance will suffer. The dynamic timing advance piston is moved according to the pressure difference between the pump inlet and the internal pressure after the vane pump and internal pressure regulator. The "out" banjo bolt has a specifically sized orifice as part of the internal pressure regulating system as well. So basically you have a specifically sized hole slowing the flow of fuel from the pump, you have a vane pump pushing the fuel in there and you have the timing piston moved according to the amount of pressure built up in the pump.

So, this brings me to the new thinner ULSD. If you change the viscosity of the fuel, you will change how easily it flows out of the orifice in the "out" bolt, and your dynamic timing advance will not function properly. Adjustment of the internal pressure regulator would seem to be necessary for any change in fuel viscosity.

Andrew
stopping
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Post by stopping »

Andrew et all,

I don't know if this is the place for questions but about the internal pressure regulator....

From the way it looks on the diagram in the pump manual... and I think Andrew has eluded to this before but the regulator works like a valve.

My question is: would the regulator function accurately enough to respond to different viscosities of fuel? And if it could do this would it keep the advance accurate?
libbybapa
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Post by libbybapa »

It is simply a pressure control valve. It would respond somewhat to different viscosities similar to the way that the oil pump pressure control valve responds to different viscosities of oil. When I run 10w-30 vs 20w-50 there is a tremendous difference in oil pressure. I am sure that initially there was a specific range of viscosity that was acceptable to the Bosch pumps. I seriously wonder if that spec is being met now. Certainly more investigation is in order.

Andrew
Fatmobile
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pump pressure

Post by Fatmobile »

Anyone have pictures or diagrams of the pressure regulator they could post?
I've torn a couple pumps apart but this isn't something I messed with.
bwv
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Post by bwv »

Is there a photo somewhere here?

viewtopic.php?t=5392&highlight=bosch
Image_________Image__________Image
__1986 [A2] Golf 1.6L, 170,000_____1988 F250, 7.3 Navistar, 197k_____1984 Ford 1510 diesel, 2222 hours
libbybapa
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Post by libbybapa »

Right here:
Image

It is a simple plunger spring assembly. Under pressure the plunger moves up and opens the passages on the side and routes fuel from after the vane pump back to the pump inlet. The indented center of the top of the regulator is a metal plug that can be tapped down slightly to increase internal pressure. To lower the pressure, the regulator can be removes, placed inverted in a vice and tapping on the bottom of the plunger should push the plug the other way.

Andrew
hagar
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I P internal pressure.

Post by hagar »

The "Holy Diesel Grail" ? according to hagar ---BOSCH 107A ---- drink of that cup --and
you will enter the land of endless SMILEAGE.

As to Andrew in Flagstaff AZ and his picture of the Pressure Control Valve ? --it blew
my socks off. ---best picture I ever saw.-----Guys look at how CLEAN his pump is --EH ?
spick and span stuff.

And yes that is the valve we have to adjust for the new SLSDF-----piece of Apple
Pie.-----NO adjustment is simpler on those pumps. ----like I said follow that Andrew guy
and you will go FAR.

hagar.
libbybapa
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Post by libbybapa »

I'd love to take the credit for such a clean pump, but it's not mine. I snagged the picture (even if the other fellows has stubby thumbs like mine... :roll: ). He doesn't have any calluses on the tips of his fingers, though. :wink: I do have a couple of other pumps here that actually are that clean, though. :D

Andrew
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