fuel pump pressure
fuel pump pressure
06-30-2011, 02:27 PM
#1
Decided to ck. lift pump pressure,was 10lbs,but gauge was oscillating between 0-10lbs almost too fast to read. pressure gauge is good and of good quality. decided to install older check valve in pump and stretch spring to 22mm and book says 26-27mm, pressure now 30lbs still oscillating. 0-30. tested check valves in lift pump both sides work well section side holds vacuum pressure side holds pressure made this test at outlet and inlet of pump. volume on pump is also good, springs on check valves stretched a small amount. checked dead end pressure of pump 65lbs still oscillating between 0-65. any ideas why it is oscillating so greatly?? car runs well and always did. thanks.
06-30-2011, 03:07 PM
#3
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Gota love Mercedes Diesels!
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DeliveryValve
06-30-2011, 03:07 PM #3Don't sweat it. It's normal, that's way it pumps with the oscillation. Good you got the pressure up though.
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Gota love Mercedes Diesels!
.
06-30-2011, 04:47 PM
#5
-Jesse
80 300sd hy35, front mount intercooler, w115 intake, rack limiter removed, Alda removed, full load turned up, boost, ebp, trans, pyro, egr delete, 3.5" exhaust, e-fan, 16x8 rims with, 245/50 tires, lowered, bilstien 5100's, 12" front brakes, 2.65:1 diff.
97 f250 psd 4x4, crawler
70 f250 390
83 Volvo 242, lots of mods
66 Volvo amazon
10 mistsubishi fuso service truck.
What's the spec?
-Jesse
80 300sd hy35, front mount intercooler, w115 intake, rack limiter removed, Alda removed, full load turned up, boost, ebp, trans, pyro, egr delete, 3.5" exhaust, e-fan, 16x8 rims with, 245/50 tires, lowered, bilstien 5100's, 12" front brakes, 2.65:1 diff.
97 f250 psd 4x4, crawler
70 f250 390
83 Volvo 242, lots of mods
66 Volvo amazon
10 mistsubishi fuso service truck.
07-01-2011, 02:26 AM
#7
1982 300D Turbo ... 3,6xxlbs, No fan, No AC, Hood Stack, No ALDA, No rear bumper and stuffed front, A/W Intercooled, Injectors by Greezer and HUGE Pre-Chambers with help from OM616 & Simpler=Better, Fuel Cranked up, 60 Trim Compressor wheel, EGT, EMP, Boost 50" Rigid Radius bar on roof Aux tank for a total of 48 Gal Of Diesel! Odyssey PC-1750 Battery in trunk, 27"x8.5"/R14 Maxxis BigHorn Mud Terrains, In June '14 issue of Off Road Mag
AX15 Jeep Trans swap in progress....
Captain America
07-01-2011, 02:26 AM #7You stretched uour spring to 22 when spec was 26-27?
1982 300D Turbo ... 3,6xxlbs, No fan, No AC, Hood Stack, No ALDA, No rear bumper and stuffed front, A/W Intercooled, Injectors by Greezer and HUGE Pre-Chambers with help from OM616 & Simpler=Better, Fuel Cranked up, 60 Trim Compressor wheel, EGT, EMP, Boost 50" Rigid Radius bar on roof Aux tank for a total of 48 Gal Of Diesel! Odyssey PC-1750 Battery in trunk, 27"x8.5"/R14 Maxxis BigHorn Mud Terrains, In June '14 issue of Off Road Mag
AX15 Jeep Trans swap in progress....
07-01-2011, 03:29 AM
#8
Just got the impression that stretching the spring that much would be too much,glad i listened . Checked pressure two places
four diff.times after venting (bleeding) system,pressure same.
Yes, 22mm gave 30lbs pressure,this was stretching spring about 4mm,easy to stretch hard to undo without cutting spring.
Just got the impression that stretching the spring that much would be too much,glad i listened . Checked pressure two places
four diff.times after venting (bleeding) system,pressure same.
07-01-2011, 02:58 PM
#9
1982 300D Turbo ... 3,6xxlbs, No fan, No AC, Hood Stack, No ALDA, No rear bumper and stuffed front, A/W Intercooled, Injectors by Greezer and HUGE Pre-Chambers with help from OM616 & Simpler=Better, Fuel Cranked up, 60 Trim Compressor wheel, EGT, EMP, Boost 50" Rigid Radius bar on roof Aux tank for a total of 48 Gal Of Diesel! Odyssey PC-1750 Battery in trunk, 27"x8.5"/R14 Maxxis BigHorn Mud Terrains, In June '14 issue of Off Road Mag
AX15 Jeep Trans swap in progress....
Captain America
07-01-2011, 02:58 PM #9Where IS the spring?
1982 300D Turbo ... 3,6xxlbs, No fan, No AC, Hood Stack, No ALDA, No rear bumper and stuffed front, A/W Intercooled, Injectors by Greezer and HUGE Pre-Chambers with help from OM616 & Simpler=Better, Fuel Cranked up, 60 Trim Compressor wheel, EGT, EMP, Boost 50" Rigid Radius bar on roof Aux tank for a total of 48 Gal Of Diesel! Odyssey PC-1750 Battery in trunk, 27"x8.5"/R14 Maxxis BigHorn Mud Terrains, In June '14 issue of Off Road Mag
AX15 Jeep Trans swap in progress....
07-01-2011, 03:48 PM
#10
Attached Files
Image(s)Gota love Mercedes Diesels!
.
DeliveryValve
07-01-2011, 03:48 PM #10It's located between the IP and engine block on the banjo of the hard plastic return line.
Attached Files
Image(s)Gota love Mercedes Diesels!
.
07-02-2011, 02:19 AM
#11
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Attached Files
Image(s)Gota love Mercedes Diesels!
.
DeliveryValve
07-02-2011, 02:19 AM #11Checking Fuel Pump and Bypass Valve procedure.
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Attached Files
Image(s)Gota love Mercedes Diesels!
.
07-02-2011, 03:42 PM
#13
(07-02-2011, 01:50 PM)richclan if i stretch spring to 26-27mm could it create too much fuel pressure and if it did what would go wrong/break.
i dont have a pressure gauge so i dont want to create a problem
tks
Yes it can. Most springs I pulled are around 20mm and a little stretch can bring the pressure up. I don't know how Mercedes came with that spec.
You can stretch it 1 mm at a time and see what each results are, just don't go over board. In the end you really ought to do it with a gauge.. Namely a glycerin filled gauge to counter act the oscillation which can be so severe you can't read the gauge.
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This post was last modified: 07-02-2011, 04:05 PM by DeliveryValve.
Gota love Mercedes Diesels!
.
DeliveryValve
07-02-2011, 03:42 PM #13(07-02-2011, 01:50 PM)richclan if i stretch spring to 26-27mm could it create too much fuel pressure and if it did what would go wrong/break.
i dont have a pressure gauge so i dont want to create a problem
tks
Yes it can. Most springs I pulled are around 20mm and a little stretch can bring the pressure up. I don't know how Mercedes came with that spec.
You can stretch it 1 mm at a time and see what each results are, just don't go over board. In the end you really ought to do it with a gauge.. Namely a glycerin filled gauge to counter act the oscillation which can be so severe you can't read the gauge.
.
Gota love Mercedes Diesels!
.
07-03-2011, 12:50 AM
#14
(07-01-2011, 03:48 PM)DeliveryValve It's located between the IP and engine block on the banjo of the hard plastic return line.
Just checked my IP, and my bolt looks like a regular banjo bolt....what's with that?
Toyota fj40 Landcruiser with a Mercedes om617 3.0L turbo diesel
![[Image: IMG_20110703_061252.jpg]](http://i41.photobucket.com/albums/e287/mr_manny/IMG_20110703_061252.jpg)
07-03-2011, 01:36 PM
#16
Only the Older type are adjustable--They have a hex-head on the back end of the main head to unscrew...
![[Image: 300TDnoplate.jpg]](http://i190.photobucket.com/albums/z128/alastairhcii/300TDnoplate.jpg)
Alastair E
07-03-2011, 01:36 PM #16Thats the later type--NON Adjustable....
Only the Older type are adjustable--They have a hex-head on the back end of the main head to unscrew...
07-03-2011, 04:14 PM
#17
(07-03-2011, 01:36 PM)Alastair E Thats the later type--NON Adjustable....
Only the Older type are adjustable--They have a hex-head on the back end of the main head to unscrew...
not fair
Toyota fj40 Landcruiser with a Mercedes om617 3.0L turbo diesel
07-04-2011, 12:30 AM
#18
Wondering if the higher back-pressure would achieve the same results, as extending the spring...
Any fellow later-banjo owners try this?
Toyota fj40 Landcruiser with a Mercedes om617 3.0L turbo diesel
What If something was added to create additional back pressure?
Wondering if the higher back-pressure would achieve the same results, as extending the spring...
Any fellow later-banjo owners try this?
Toyota fj40 Landcruiser with a Mercedes om617 3.0L turbo diesel
07-04-2011, 01:15 AM
#19
-Jesse
80 300sd hy35, front mount intercooler, w115 intake, rack limiter removed, Alda removed, full load turned up, boost, ebp, trans, pyro, egr delete, 3.5" exhaust, e-fan, 16x8 rims with, 245/50 tires, lowered, bilstien 5100's, 12" front brakes, 2.65:1 diff.
97 f250 psd 4x4, crawler
70 f250 390
83 Volvo 242, lots of mods
66 Volvo amazon
10 mistsubishi fuso service truck.
You want a adjustable one? I think I have a few.
-Jesse
80 300sd hy35, front mount intercooler, w115 intake, rack limiter removed, Alda removed, full load turned up, boost, ebp, trans, pyro, egr delete, 3.5" exhaust, e-fan, 16x8 rims with, 245/50 tires, lowered, bilstien 5100's, 12" front brakes, 2.65:1 diff.
97 f250 psd 4x4, crawler
70 f250 390
83 Volvo 242, lots of mods
66 Volvo amazon
10 mistsubishi fuso service truck.
07-04-2011, 04:49 AM
#20
(07-04-2011, 01:15 AM)dieselboy You want a adjustable one? I think I have a few.
I need this too
hansebanger77
07-04-2011, 04:49 AM #20(07-04-2011, 01:15 AM)dieselboy You want a adjustable one? I think I have a few.
I need this too
07-05-2011, 03:25 PM
#23
(07-05-2011, 02:40 PM)mr_manny Was wondering, has anyone plumped an analog pressure gauge under the hood?
Being able to verify fuel pressure with only a glance, seems like a good thing to me
You mean keeping it under the hood? That would be fine.
But putting it in the cabin, some manufactures think the pressure is too great to put it in the cabin and may cause injury if something goes wrong.
Here are a couple gauges that should work.
http://www.summitracing.com/parts/FRA-900004/?rtype=10
http://www.jegs.com/i/Auto+Meter/105/5412/10002/-1
.
Gota love Mercedes Diesels!
.
DeliveryValve
07-05-2011, 03:25 PM #23(07-05-2011, 02:40 PM)mr_manny Was wondering, has anyone plumped an analog pressure gauge under the hood?
Being able to verify fuel pressure with only a glance, seems like a good thing to me
You mean keeping it under the hood? That would be fine.
But putting it in the cabin, some manufactures think the pressure is too great to put it in the cabin and may cause injury if something goes wrong.
Here are a couple gauges that should work.
http://www.summitracing.com/parts/FRA-900004/?rtype=10
http://www.jegs.com/i/Auto+Meter/105/5412/10002/-1
.
Gota love Mercedes Diesels!
.
07-05-2011, 07:19 PM
#24
(07-01-2011, 03:29 AM)Hercules Yes, 22mm gave 30lbs pressure,this was stretching spring about 4mm,easy to stretch hard to undo without cutting spring.
Just got the impression that stretching the spring that much would be too much,glad i listened . Checked pressure two places
four diff.times after venting (bleeding) system,pressure same.
I did a quick google conversion, and 30lbs pressure seems much higher then stated specifications.
![[Image: fuel.jpg]](http://i41.photobucket.com/albums/e287/mr_manny/fuel.jpg)
0.6 bar = 8.7 psi
0.8 bar = 11.6 psi
2.0 bar = 30.0 psi
I take it the higher pressure helps w/0-60 times?
Toyota fj40 Landcruiser with a Mercedes om617 3.0L turbo diesel
(07-01-2011, 03:29 AM)Hercules Yes, 22mm gave 30lbs pressure,this was stretching spring about 4mm,easy to stretch hard to undo without cutting spring.
Just got the impression that stretching the spring that much would be too much,glad i listened . Checked pressure two places
four diff.times after venting (bleeding) system,pressure same.
I did a quick google conversion, and 30lbs pressure seems much higher then stated specifications.
0.6 bar = 8.7 psi
0.8 bar = 11.6 psi
2.0 bar = 30.0 psi
I take it the higher pressure helps w/0-60 times?
Toyota fj40 Landcruiser with a Mercedes om617 3.0L turbo diesel
07-05-2011, 11:40 PM
#25
the lift pump is the limiting factor to go higher than approx. 1.5-2 bar.
Easy to check: run the engine at idle and close the return line from the IP back into the filter with a vice grip and check the pressure between filter and pump (supply side).
When the pressure increases the over flow valve at the IP return side could be better (and you will notice that the engine idles more quiet).
If the pressure stays the same then the valve is o.k. and the lift pump is already at its max.
I am working on 2.5 - 2 bar under all conditions.
The easiest way is to change the spring in the lift pump.
Tom
Hi,
the lift pump is the limiting factor to go higher than approx. 1.5-2 bar.
Easy to check: run the engine at idle and close the return line from the IP back into the filter with a vice grip and check the pressure between filter and pump (supply side).
When the pressure increases the over flow valve at the IP return side could be better (and you will notice that the engine idles more quiet).
If the pressure stays the same then the valve is o.k. and the lift pump is already at its max.
I am working on 2.5 - 2 bar under all conditions.
The easiest way is to change the spring in the lift pump.
Tom
07-06-2011, 12:21 AM
#27
1982 300D Turbo ... 3,6xxlbs, No fan, No AC, Hood Stack, No ALDA, No rear bumper and stuffed front, A/W Intercooled, Injectors by Greezer and HUGE Pre-Chambers with help from OM616 & Simpler=Better, Fuel Cranked up, 60 Trim Compressor wheel, EGT, EMP, Boost 50" Rigid Radius bar on roof Aux tank for a total of 48 Gal Of Diesel! Odyssey PC-1750 Battery in trunk, 27"x8.5"/R14 Maxxis BigHorn Mud Terrains, In June '14 issue of Off Road Mag
AX15 Jeep Trans swap in progress....
Captain America
07-06-2011, 12:21 AM #27Delivery Valve is my hero
1982 300D Turbo ... 3,6xxlbs, No fan, No AC, Hood Stack, No ALDA, No rear bumper and stuffed front, A/W Intercooled, Injectors by Greezer and HUGE Pre-Chambers with help from OM616 & Simpler=Better, Fuel Cranked up, 60 Trim Compressor wheel, EGT, EMP, Boost 50" Rigid Radius bar on roof Aux tank for a total of 48 Gal Of Diesel! Odyssey PC-1750 Battery in trunk, 27"x8.5"/R14 Maxxis BigHorn Mud Terrains, In June '14 issue of Off Road Mag
AX15 Jeep Trans swap in progress....
07-06-2011, 01:20 AM
#28
What fuel pressure would be too much ?? Mbz said stretch spring 26-27mm I stopped at 22mm. Well not the first time had to redo a repair following mbz instructions! Will leave at present setting,A stretched spring will ,decrease in tension 20% +/- very soon,undampened gauge bounces several lbs.higher,will end up having lower pressure. The higher pressure did improve performance over all speeds ,Just much more fun to drive. I would how ever suggest to stop at 20 lbs of fuel pressure so as not to over stress parts. (Good Day), is finding improved performance, with little money and time!!
07-06-2011, 01:39 AM
#29
This post was last modified: 07-06-2011, 01:39 AM by Captain America.
1982 300D Turbo ... 3,6xxlbs, No fan, No AC, Hood Stack, No ALDA, No rear bumper and stuffed front, A/W Intercooled, Injectors by Greezer and HUGE Pre-Chambers with help from OM616 & Simpler=Better, Fuel Cranked up, 60 Trim Compressor wheel, EGT, EMP, Boost 50" Rigid Radius bar on roof Aux tank for a total of 48 Gal Of Diesel! Odyssey PC-1750 Battery in trunk, 27"x8.5"/R14 Maxxis BigHorn Mud Terrains, In June '14 issue of Off Road Mag
AX15 Jeep Trans swap in progress....
Captain America
07-06-2011, 01:39 AM #29How about adding shims under the spring to increase tension without stretching? Keep in mind I have not looked at one in front of me yet
1982 300D Turbo ... 3,6xxlbs, No fan, No AC, Hood Stack, No ALDA, No rear bumper and stuffed front, A/W Intercooled, Injectors by Greezer and HUGE Pre-Chambers with help from OM616 & Simpler=Better, Fuel Cranked up, 60 Trim Compressor wheel, EGT, EMP, Boost 50" Rigid Radius bar on roof Aux tank for a total of 48 Gal Of Diesel! Odyssey PC-1750 Battery in trunk, 27"x8.5"/R14 Maxxis BigHorn Mud Terrains, In June '14 issue of Off Road Mag
AX15 Jeep Trans swap in progress....
07-07-2011, 10:29 PM
#30
![[Image: IMG_20110707_201939.jpg]](http://i41.photobucket.com/albums/e287/mr_manny/IMG_20110707_201939.jpg)
Jesse is taking care of me w/an early design Adjustable Banjo
looking forward to pluming this up, need to get more fittings...
This post was last modified: 07-07-2011, 10:51 PM by mr_manny.
Toyota fj40 Landcruiser with a Mercedes om617 3.0L turbo diesel
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