Go Back   Team-BHP > Buckle Up > 4x4 & Off-Roading > 4x4 Technical


Reply
 
Thread Tools Search this Thread
Old 27th February 2011, 14:12   #46
Senior - BHPian
 
SPIKE ARRESTOR's Avatar
 
Join Date: Nov 2009
Location: Deutschland
Posts: 2,653
Thanked: 679 Times
Default Re: FIP Flop

Quote:
Originally Posted by Sudarshan View Post
most welcome . (a fuel circuit chart will also do )
Attaching a generic layout for clearer understanding.

FIP Flop-1.jpg

Quote:
Now with this reference what is the position in CRDe & electronically controlled units ?
Priming location in fuel filter:-

FIP Flop-2.jpg

Quote:
Is the Bleeding part important or its simply not there ? (Can do without that ? )
It is still important. Despite everything, there are possibilities which may result in air getting trapped in the fuel lines hence priming / bleeding becomes imperative (hence the hand primer is provided). All depends on how much air is trapped. Attaching a pic showing the inlet and outlet locations.

Name:  3.jpg
Views: 423
Size:  24.4 KB

Hope it is clear now.

Spike
SPIKE ARRESTOR is offline   Reply With Quote
Old 27th February 2011, 17:22   #47
BANNED
 
Join Date: Apr 2010
Location: Pune
Posts: 1,201
Thanked: 821 Times
Default Re: FIP Flop

Quote:
Originally Posted by SPIKE ARRESTOR View Post

Hope it is clear now.

Spike
Thanks for the information .

its very much clear now .

I still have one doubt , is there any bleed screw on the high pressure pump ? ( just like the old FE pump ? )

Thanks

Sudarshan
Sudarshan is offline   Reply With Quote
Old 27th February 2011, 20:11   #48
Distinguished - BHPian
 
Join Date: Jul 2009
Location: Kolkata
Posts: 3,444
Thanked: 1,942 Times
Default Re: FIP Flop

Logically,the rail should have a bleed, at a point farthest from the pressure pump connection. However, given the pressures involved, chances of serious injury are extremely high. Thats why I think there are no user accessible bleeds.

I guess at CR pressures, air just dissolves in the fuel. And a piezo injector is electrically opened, so air should not be that serious a problem. Of course, without fuel (lubricant) you are likely to ruin your pump.

Prateesh, comments.

Regards
Sutripta

Edit: Are engines or injectors susceptible to bends?

Last edited by Sutripta : 27th February 2011 at 20:21.
Sutripta is offline   Reply With Quote
Old 27th February 2011, 20:49   #49
Distinguished - BHPian
 
Mpower's Avatar
 
Join Date: Mar 2005
Location: Bangalore
Posts: 10,430
Thanked: 1,678 Times
Default Re: FIP Flop

Quote:
Originally Posted by SPIKE ARRESTOR View Post
Attaching a generic layout for clearer understanding.

Hope it is clear now.

Spike
I don't see the electric in-tank lift pump.

Last edited by Mpower : 28th February 2011 at 21:41.
Mpower is offline   Reply With Quote
Old 27th February 2011, 22:45   #50
BHPian
 
star_aqua's Avatar
 
Join Date: Aug 2008
Location: BLR
Posts: 612
Thanked: 88 Times
Default Re: FIP Flop

Quote:
Originally Posted by Sudarshan View Post

I still have one doubt , is there any bleed screw on the high pressure pump ? ( just like the old FE pump ? )
As Spike said all you need is to fill the diesel and crank continuously till it starts. For second try priming is preferred with key ON. Bleeding can be done only in low pressure circuit but not possible in the high pressure circuit. The CR system will take care of bleeding in high pressure circuit automatically. While cranking if there is no pressure buildup in the rail, the system goes into venting mode for a while which will vent out the air through injectors and switches to pressure build up mode. this repeats until the minimum pressure to make injection is achieved.
star_aqua is offline   Reply With Quote
Old 28th February 2011, 09:29   #51
Senior - BHPian
 
SPIKE ARRESTOR's Avatar
 
Join Date: Nov 2009
Location: Deutschland
Posts: 2,653
Thanked: 679 Times
Default Re: FIP Flop

Quote:
Originally Posted by Sutripta View Post
However, given the pressures involved, chances of serious injury are extremely high. Thats why I think there are no user accessible bleeds.
Yes, pretty true.

Quote:
I guess at CR pressures, air just dissolves in the fuel. And a piezo injector is electrically opened, so air should not be that serious a problem. Of course, without fuel (lubricant) you are likely to ruin your pump.
Yes, it is recommended that engine must not be started without fuel, every HP pump has a minimum quantity of fuel specified for operation.

Quote:
Edit: Are engines or injectors susceptible to bends?
Bends from?

Quote:
Originally Posted by star_aqua View Post
The CR system will take care of bleeding in high pressure circuit automatically. While cranking if there is no pressure buildup in the rail, the system goes into venting mode for a while which will vent out the air through injectors and switches to pressure build up mode. this repeats until the minimum pressure to make injection is achieved.
Well said

Spike
SPIKE ARRESTOR is offline   Reply With Quote
Old 28th February 2011, 20:30   #52
Distinguished - BHPian
 
Join Date: Jul 2009
Location: Kolkata
Posts: 3,444
Thanked: 1,942 Times
Default Re: FIP Flop

Quote:
Originally Posted by star_aqua View Post
...While cranking if there is no pressure buildup in the rail, the system goes into venting mode for a while which will vent out the air through injectors and switches to pressure build up mode. this repeats until the minimum pressure to make injection is achieved.
Hi,
A couple of questions.
A) How does the ECU know there is no rail pressure?
B) Venting done only through injectors?
C) When through injectors, when? Power stroke, or exhaust stroke.

@Spike
Re: bends, was joking. (Bends = Caisson disease)

Regards
Sutripta

Last edited by Sutripta : 28th February 2011 at 20:33.
Sutripta is offline   Reply With Quote
Old 28th February 2011, 20:57   #53
BHPian
 
star_aqua's Avatar
 
Join Date: Aug 2008
Location: BLR
Posts: 612
Thanked: 88 Times
Default Re: FIP Flop

Quote:
Originally Posted by Sutripta View Post
Hi,
A couple of questions.
A) How does the ECU know there is no rail pressure?
B) Venting done only through injectors?
C) When through injectors, when? Power stroke, or exhaust stroke.

Regards
Sutripta
A) through rail pressure sensor
B) it is only for the systems which doesn't have pressure control valve(PCV) or else PCV is used.
C) exhaust stroke
star_aqua is offline   Reply With Quote
Old 28th February 2011, 21:17   #54
Distinguished - BHPian
 
Join Date: Jul 2009
Location: Kolkata
Posts: 3,444
Thanked: 1,942 Times
Default Re: FIP Flop

^^^
Hi,
Do you know what type of sensor? And what accuracy? > 1000 bar, hot or cold, is not a joke.

I was thinking about one thing. I one runs the pump long enough, air or no air, pressure will build up. So it must be a timed thing. Is it?

Air in system/ venting: - Is it stored in the fault log?

Regards
Sutripta
Sutripta is offline   Reply With Quote
Old 28th February 2011, 23:47   #55
BHPian
 
star_aqua's Avatar
 
Join Date: Aug 2008
Location: BLR
Posts: 612
Thanked: 88 Times
Default Re: FIP Flop

Quote:
Originally Posted by Sutripta View Post

Do you know what type of sensor? And what accuracy? > 1000 bar, hot or cold, is not a joke.
Its made of steel membrane with metal thin film and more details which you are looking for is here http://apps.bosch.com.au/motorsport/...ghpressure.pdf

The hot and cold diesel makes lot of difference in the rail pressure when metering unit(fuel metering done at low pressure side) is used for controlling the pressure instead of PCV.

Quote:

I was thinking about one thing. I one runs the pump long enough, air or no air, pressure will build up. So it must be a timed thing. Is it?
yes, exactly. there is a specified time for specific pressure to build up at specified rpm when pumping diesel. the time is very high for air as it is compressible and takes more revolutions and which means more time taken to build up the pressure. There is a timeout as the expected pressure is not reached within expected time.

Quote:
Air in system/ venting: - Is it stored in the fault log?
'Air in system' fault will be stored in the fault log only if empty tank is not detected.
star_aqua is offline   Reply With Quote
Old 1st March 2011, 09:17   #56
Senior - BHPian
 
SPIKE ARRESTOR's Avatar
 
Join Date: Nov 2009
Location: Deutschland
Posts: 2,653
Thanked: 679 Times
Default Re: FIP Flop

Quote:
Originally Posted by Sutripta View Post
@Spike
Re: bends, was joking. (Bends = Caisson disease)
I didn't know that. Dada, BTW congrats on becoming a D-BHPIAN, you truly deserve it

Quote:
Originally Posted by star_aqua View Post
Its made of steel membrane with metal thin film and more details which you are looking for is here http://apps.bosch.com.au/motorsport/...ghpressure.pdf
Star, which sensor are we talking of here? The link doesn't seem to be working in my system, some problem may be.

Spike
SPIKE ARRESTOR is offline   Reply With Quote
Old 1st March 2011, 11:43   #57
BHPian
 
star_aqua's Avatar
 
Join Date: Aug 2008
Location: BLR
Posts: 612
Thanked: 88 Times
Default Re: FIP Flop

Quote:
Originally Posted by SPIKE ARRESTOR View Post

Star, which sensor are we talking of here? The link doesn't seem to be working in my system, some problem may be.
Its the high pressure sensors spike. can be used for applications which need measurements upto 2200bar.
its a link to a pdf file. must be something wrong with your pc.
star_aqua is offline   Reply With Quote
Old 1st March 2011, 15:46   #58
Distinguished - BHPian
 
Join Date: Jul 2009
Location: Kolkata
Posts: 3,444
Thanked: 1,942 Times
Default Re: FIP Flop

Quote:
Originally Posted by SPIKE ARRESTOR View Post
Dada, BTW congrats on becoming a D-BHPIAN, you truly deserve it
Spike
Thanks Prateesh. Appreciated.

Quote:
Originally Posted by star_aqua View Post
Its made of steel membrane with metal thin film and more details which you are looking for is here
......
'Air in system' fault will be stored in the fault log only if empty tank is not detected.
Hi Vijay,
Would suggest that you start a thread titled 'CRDIs for dummies'. But till such time here are a few more questions and comments.

Surprised to see that the pressure sensor is essentially a standard design, configured as a transmitting head. What surprised me was that
A) It was not a double diaphragm design.
B) It has a shelf life. (Why)

You had also mentioned that metering is done on the low pressure side. Could you expand on that please. Actually, lots of questions about metering. And total injection time.

Regards
Sutripta

Last edited by Sutripta : 1st March 2011 at 15:47.
Sutripta is offline   Reply With Quote
Old 1st March 2011, 23:39   #59
BHPian
 
star_aqua's Avatar
 
Join Date: Aug 2008
Location: BLR
Posts: 612
Thanked: 88 Times
Default Re: FIP Flop

Quote:
Originally Posted by Sutripta View Post
Would suggest that you start a thread titled 'CRDIs for dummies'. But till such time here are a few more questions and comments.
Will do when time permits

Quote:


You had also mentioned that metering is done on the low pressure side. Could you expand on that please. Actually, lots of questions about metering. And total injection time.
The pressure can be regulated by metering the fuel on low pressure side as well as on the high pressure side.
The first generation CR system had the metering control on the high pressure side. The second generation had on low pressure side and later generations come with coupled control where the metering is done on both side.

The disadvantage of fuel metering on low pressure side is bringing down the rail pressure rapidly when desired is not possible and the pressure buildup is fuel temperature dependent in which metering cannot be done precisely. The advantage is pump load on engine can be varied based on the pressure requirement, hence more efficient.

when only PCV is used(high pressure side control), the disadvantage is the pump always works with its full load on the engine which is unnecessary, hence less efficient.
when both are used, the system is more efficient and robust as there is always a backup if one of the low or high pressure side control fails.
star_aqua is offline   Reply With Quote
Old 2nd March 2011, 00:18   #60
Distinguished - BHPian
 
Join Date: Jul 2009
Location: Kolkata
Posts: 3,444
Thanked: 1,942 Times
Default Re: FIP Flop

Hi,
You mean throttling the input? Will that not lead to flash boiling of the fuel, and maybe even cavitation?

BTW, what is the nature of the pump?

Regards
Sutripta
Sutripta is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Flop cars in our market bhp The Indian Car Scene 474 1st July 2017 15:22
The "FLOP SHOW" is over R.I.P Jaspal Bhatti adg_andy Shifting gears 38 2nd February 2013 23:32
Flip Flop between Bajaj Auto & Renault Nissan on small car RemingtonSteele The Indian Car Scene 6 16th July 2011 11:19
Acura accepts RL is a sales flop amit The International Automotive Scene 8 9th March 2006 06:44


All times are GMT +5.5. The time now is 23:14.

Copyright 2000 - 2017, Team-BHP.com
Proudly powered by E2E Networks