VE Bosch Injection Pump Internal Pressures. NOT 155Bar!!!!!!

[smutts]

Does anyone out there actually know the values of RPM versus the internal pump pressure for the Bosch pumps for the RA or SB turbodiesel engines? I know Mr Hagar has some recomendations on the Dieselparts forum, but will I be reduced to illegal downloads of cracked "Bosch ESItronic" just to be able to adjust my own bloody property with certainty? VW's & Bosch's dog in the mangerness is annoying. :twisted:  :twisted:  :roll:

[zukgod1]

There has been much talk about internal pump pressures.

Did you try the search function?

[theman53]

there is this
http://www.vwdieselparts.com/forum/viewtopic.php?t=5936&sid=4cdedce621f8949049c249f58d83c028
there was another I believe that was 103 pages long, but this should get you the idea without so much downloading of stuff. I think they go through the RPM values and corrisponding pressures. Hope it helps.

[Vincent Waldon]

I did this graph based on the initial numbers provided by Bosch:



but the entire thread is well worth reading...

[Op-Ivy]

Read the whole thread for sure! Lots of good info on it.

[smutts]

Apologies for the rant, but my attitude is if I bought your product, then you should also provide the information to look after it. Especially if it is adjusted by a special tool, ie a hammer, then claiming this knowledge is beyond the ken of the common man or woman is a bit tedious. :lol:
  So here is where we are so far, VW GTD, 1600cc intercooled turbodiesel, SB engine code. 150000 miles, 47mpg/imperial gallon, 39mpg/USgallon.
  Pump pressure as found, bar/engine rpm, 2.4/1000, 3.0/1500, 3.4/2000, 4.0/2500.
  Pump pressure after a gentle tap on the valve, 3.4/1000, 3.8/1500, 4.3/2000, 5.0/2500.
  Driving impressions? The higher rev range appears to be improved, but lower down, not so sure. The engine sounds slightly harsher, but not like a shaken jar of marbles at all.
  This is getting addictive, now where can I find the factory info for the original pressure vs rpm?  :twisted:

[jtanguay]

Apologies for the rant, but my attitude is if I bought your product, then you should also provide the information to look after it.

mechanics wouldn't make any money then!  :lol:

[theman53]

The guy who has this software could probably answer your question on the specifics, but I think vince already did. This is just in case you have to hear it from VW.

Tintin wrote:
Here the original ''BOSCH'' tool to adjust pressure regulator:

 

And here the description of the BOSCH ESITRONIC software:

 

The majority of the IDI pump, the pressure are 0 - 100psi, and for a specific DI pump, the pressure can go up until 160psi, and no seal leak.

To adjust the timing curve, it's more easy with the regulator, and it is conceived has this end.

And for the regulator them even, there exist with different pressure curved, (different hardness from spring, different size of bleed port and 2 or 4 bleed port)

[smutts]

Aha! I actually read the instructions on the search function, insert "and" and voila! Doh! :wink:
Sorry for all the starving mechanics out there! But my beef was the attitude that someone charges £40 per hour to read THAT book and hit the pump with a hammer. With a newish car, happy. With a 20 year old car, less happy. Perhaps I'm just tight. :twisted:

[jtanguay]

Aha! I actually read the instructions on the search function, insert "and" and voila! Doh! :wink:
Sorry for all the starving mechanics out there! But my beef was the attitude that someone charges £40 per hour to read THAT book and hit the pump with a hammer. With a newish car, happy. With a 20 year old car, less happy. Perhaps I'm just tight. :twisted:

well i'm sure Giles uses a different technique than using a hammer to adjust internal pressures  :wink:  i doubt there are any mechanics out there who know that much about these pumps... (fueling, idle, timing..?)

thats why this site rules though.  the information exchange here is empowing people to do their own work and save.  

[Tintin]

The fact is that there are no bosch document which says to put such pressure for such RPM and the timing is ok, in fact yes, but no.....

Ex: If you play with the internal pressure it is exactly like adjusting a gas motor distributor without timing light, you play with it, but you do not have any idea of what occurs with the timing, there are no document that says  ''turn the distributor for 4deg of rotation to get 12 deg BTDC.... ''  you will have to monitor the timing with timing light or proper tool.

Diesel is the same, on the bench test there is a tool to measure the pump timing at different RPM,  the internal pump pressure value giving by Boch for each pump is to check if the pressure system is ok before doing work on the pump, and when you adjust the timing, no need to see the pressure.

I know that all 1.6 pump are identical, have same pieces in it, thus all have approximately the same pressure, but you can only roughly suppose that for X pressure that should be close to the correct adjustment.

[Tintin]

what you really want to do is to leave the low RPM timing alone and increase the higher RPM timing advance.

I don't know what brings you to that conclusion.

Andrew

It's right that a softer timing spring keep the low rpm timing and increase more the hight rpm timing, but It's hard to find a proper adjustment without doing a regulator adjustment at the same time.

A harder spring in the regulator and/or smaller bleed hole in it do the same thing, and it is more easy to play, but be sure if it is properly adjusted, but a regulator has a small window of adjustment, exeed a certain point you cannot play more with it and the timing is out of control.

[smutts]

Exactly. As I don't want to bulldoze holes in the pistons, or kill the big ends. From my limited twiddling, the tapping the transfer valve seems to add the same pressure across the whole rev range. Tap gently, as it is suprisingly sensitive.
Somewhere else I read that the O rings that seal the transfer valve can leak and bypass the valve, something else to go wrong I suppose.
I assume that the raised pressure helps to keep the fuel together as it gets sucked into the injection head. Would cavitation be likely if the internal pressure was too low?
A facinating bag of worms!

[Tintin]

Directly connected in any event, but I agree that this information is irrelevant for your cause.

Yes a bad seal can bypass some presure, but maybee It's negligible if you take the flow in consideration.

I really dont think that this mini 4 cyl plunger can undergo a cavitation, take for example a first generation of cummins 6BT (5.9Lmotor) with VE pump, it have a 12mm plunger with 6 delivery port maxed with big injector, at 100KM/H that engine consume over 12-14L an hour trought the plunger without cavitation.

The only large difficulty in these pumps is to make work correctly the timing mechanism for what the engine has need, and timing mechanism = X pump pressure VS RPM.

If you tap on the regulator, in certain case of too much tapping that do not increase equal pressure at each RPM, that increase much pressure at low rpm... too much..... but not much at hight rpm, that need to play with several combination of timing and regulator spring.

 

Exactly. As I don't want to bulldoze holes in the pistons, or kill the big ends. From my limited twiddling, the tapping the transfer valve seems to add the same pressure across the whole rev range. Tap gently, as it is suprisingly sensitive.

Somewhere else I read that the O rings that seal the transfer valve can leak and bypass the valve, something else to go wrong I suppose.
I assume that the raised pressure helps to keep the fuel together as it gets sucked into the injection head. Would cavitation be likely if the internal pressure was too low?
A facinating bag of worms!