Turning the delivery valve holder
Turning the delivery valve holder
Lincolnlock
08-15-2008, 08:37 AM #1So I know that this is my first post but I thought I would share what I know. On a Cummins 12 valve you can loosen the injector line, and hold down nuts for the delivery valves, and turn each delivery valve clockwise until it stops. These only turn a little bit, but quite a bit more fuel can be had. I performed this on my 81' 300td last night and got very good results. There is one side effect by doing this however. The idle will significantly higher and will need to be adjusted down to an acceptable level. Also, some engines will have a slight lope at idle. My Mercedes does not have any issues with idle but I had to turn the idle screw out about 3 turns. I started the car cold this morning with no side effects. Many of the Cummins trucks in the area have been running this mod for several years, and tow frequently.
Lincolnlock So I know that this is my first post but I thought I would share what I know. On a Cummins 12 valve you can loosen the injector line, and hold down nuts for the delivery valves, and turn each delivery valve clockwise until it stops. These only turn a little bit, but quite a bit more fuel can be had. I performed this on my 81' 300td last night and got very good results. There is one side effect by doing this however. The idle will significantly higher and will need to be adjusted down to an acceptable level. Also, some engines will have a slight lope at idle. My Mercedes does not have any issues with idle but I had to turn the idle screw out about 3 turns. I started the car cold this morning with no side effects. Many of the Cummins trucks in the area have been running this mod for several years, and tow frequently.This should be adjusting the individual delivery timing, interesting that has beneficial result. Do you have an EGT in the MB? Where are you located?
1987 300D Sturmmachine
1991 300D Nearly Perfect
1985 300D Weekend/Camping/Dog car
1974 L508D Motoroam Monarch "NightMare"
OBK #42
Lincolnlock So I know that this is my first post but I thought I would share what I know. On a Cummins 12 valve you can loosen the injector line, and hold down nuts for the delivery valves, and turn each delivery valve clockwise until it stops. These only turn a little bit, but quite a bit more fuel can be had. I performed this on my 81' 300td last night and got very good results. There is one side effect by doing this however. The idle will significantly higher and will need to be adjusted down to an acceptable level. Also, some engines will have a slight lope at idle. My Mercedes does not have any issues with idle but I had to turn the idle screw out about 3 turns. I started the car cold this morning with no side effects. Many of the Cummins trucks in the area have been running this mod for several years, and tow frequently.This should be adjusting the individual delivery timing, interesting that has beneficial result. Do you have an EGT in the MB? Where are you located?
1987 300D Sturmmachine
1991 300D Nearly Perfect
1985 300D Weekend/Camping/Dog car
1974 L508D Motoroam Monarch "NightMare"
OBK #42
Lincolnlock
08-15-2008, 10:12 AM #3I'm in Seattle. No pyro on the car. I have them on the trucks though. EGT's come up some but not much. There is some power to be had here. I need to know that I can get some fuel to this thing before I dump a whole bunch of money into this. I already have a stock hy-9 from a cummins that I'll install with a front mount later. There is no way I'll be able to use all that air without a bunch more fuel. I guess it's time to pull the back of the IP off and get to work. I've got a 550 whp dodge so I'm not new to this stuff. I'm having fun with this new project though. I already lowered the car a bit and put on some 17's. I've had the car 2 weeks and I pulled it out of the Olympic rain forest out here. It had been sitting for quite a while. I need to fix a bunch of stuff still. I think the flex plate is cracked. So... maybe a 4 speed swap? I dunno.
Lincolnlock I'm in Seattle. No pyro on the car. I have them on the trucks though. EGT's come up some but not much. There is some power to be had here. I need to know that I can get some fuel to this thing before I dump a whole bunch of money into this. I already have a stock hy-9 from a cummins that I'll install with a front mount later. There is no way I'll be able to use all that air without a bunch more fuel. I guess it's time to pull the back of the IP off and get to work. I've got a 550 whp dodge so I'm not new to this stuff. I'm having fun with this new project though. I already lowered the car a bit and put on some 17's. I've had the car 2 weeks and I pulled it out of the Olympic rain forest out here. It had been sitting for quite a while. I need to fix a bunch of stuff still. I think the flex plate is cracked. So... maybe a 4 speed swap? I dunno.Good times, too have to do the rack limiter removal on my new engine. I have been delinquent on getting my turbo and IC installed but I have sworn I am going to do it before Fall is over.
Love the Pacific NW, my grandmom used to live up in the gorge.
1987 300D Sturmmachine
1991 300D Nearly Perfect
1985 300D Weekend/Camping/Dog car
1974 L508D Motoroam Monarch "NightMare"
OBK #42
Lincolnlock I'm in Seattle. No pyro on the car. I have them on the trucks though. EGT's come up some but not much. There is some power to be had here. I need to know that I can get some fuel to this thing before I dump a whole bunch of money into this. I already have a stock hy-9 from a cummins that I'll install with a front mount later. There is no way I'll be able to use all that air without a bunch more fuel. I guess it's time to pull the back of the IP off and get to work. I've got a 550 whp dodge so I'm not new to this stuff. I'm having fun with this new project though. I already lowered the car a bit and put on some 17's. I've had the car 2 weeks and I pulled it out of the Olympic rain forest out here. It had been sitting for quite a while. I need to fix a bunch of stuff still. I think the flex plate is cracked. So... maybe a 4 speed swap? I dunno.Good times, too have to do the rack limiter removal on my new engine. I have been delinquent on getting my turbo and IC installed but I have sworn I am going to do it before Fall is over.
Love the Pacific NW, my grandmom used to live up in the gorge.
1987 300D Sturmmachine
1991 300D Nearly Perfect
1985 300D Weekend/Camping/Dog car
1974 L508D Motoroam Monarch "NightMare"
OBK #42
Lincolnlock
08-16-2008, 01:35 AM #5Basically where the delivery valves are there are two nuts that hold the delivery valve housing down. Loosen the injector lines a little. Loosen the two nuts just below the injectors lines. Use a 15mm wrench and turn the delivery valve clockwise until it stops. Tighten the two nuts and the injector line. Start the engine and turn down the idle. Then go for a test drive and enjoy!
If you do want to mess with that setting its strongly recommended to have a properly calibrated (or unaltered used) spare injection pump on hand.
ForcedInduction
08-16-2008, 06:00 AM
#6
That is turning the plunger barrel timing, not the delivery valves. That is not a good thing to do. That setting is very sensitive and messing with them can result in a very poor running engine and only adjusting the pump on a test bench can get them back into proper calibration.
If you do want to mess with that setting its strongly recommended to have a properly calibrated (or unaltered used) spare injection pump on hand.
Lincolnlock
08-16-2008, 06:45 PM #8Mine were gross enough I could put it back if I needed to. The dirt is a good indicator. There are tons of people running this. I just couldn't find anything on it so I posted up.
If you really want to flow a LOT more fuel, either grind the collar off the DVs or have them machined, and hog out the injectors. My next target is injectors.
You may also be interested to read about the Torque Control adjustment procedure. Another place where you might have some fun is by simply cranking the governor limit up to ~5500rpm. I wouldn't do any of this without big air, big intercooler, and a pyro.
btw- i'm running an HX30 and just the extra air alone helps power in the top end
GREASY_BEAST
08-18-2008, 08:34 PM #9Like ForcedInduction said, what you turned was not the delivery valve holder. The delivery valve holder is easily removed by unscrewing the 15mm thing you grabbed hold of and lifting it out. I wonder if your mod didn't do the same thing as the rack limiter removal... maybe it is possible to make additional gains (on top of rack limiter removal) by this method??
If you really want to flow a LOT more fuel, either grind the collar off the DVs or have them machined, and hog out the injectors. My next target is injectors.
You may also be interested to read about the Torque Control adjustment procedure. Another place where you might have some fun is by simply cranking the governor limit up to ~5500rpm. I wouldn't do any of this without big air, big intercooler, and a pyro.
btw- i'm running an HX30 and just the extra air alone helps power in the top end
1987 300D Sturmmachine
1991 300D Nearly Perfect
1985 300D Weekend/Camping/Dog car
1974 L508D Motoroam Monarch "NightMare"
OBK #42
1987 300D Sturmmachine
1991 300D Nearly Perfect
1985 300D Weekend/Camping/Dog car
1974 L508D Motoroam Monarch "NightMare"
OBK #42
There is certainly a lopey idle. I adjusted the rack dampener pin but I think its just masking the underlying issue. I am going to start calling around. This was certainly a drastic improvement which makes me think its just time to the the IP on a bench.
1987 300D Sturmmachine
1991 300D Nearly Perfect
1985 300D Weekend/Camping/Dog car
1974 L508D Motoroam Monarch "NightMare"
OBK #42
Lincolnlock
12-14-2008, 08:40 PM #12What I have found is that usually there is one cylinder that isn't getting enough fuel at idle because you can actually turn them a little to far. To figure which one it is just start the car, let it idle, crack each injector until you find the one that has very little or no fuel to it at idle, and adjust the delivery valve back until you get the idle to clean up. Also, I turned down the idle quantity a bit and that helped clean up the idle smoke all together, even when cold.
http://www.nwbombers.com/forums/index.ph...t&p=146235
Sounds like removing the shims may give additional power, I may try this out tomorrow.
I read an interesting bit here :
http://www.nwbombers.com/forums/index.ph...t&p=146235
Sounds like removing the shims may give additional power, I may try this out tomorrow.
(01-04-2009, 12:53 AM)winmutt I read an interesting bit here :
http://www.nwbombers.com/forums/index.ph...t&p=146235
Sounds like removing the shims may give additional power, I may try this out tomorrow.
If we are talking about the shims under the barrel flange, then you will change individual timing, nothing else.
Changing something directly under the DV could change the spring load of the DV piston. But it will be much easier to change the spring itself.
Please help me to understand what part we are talking about.
Tom
(01-04-2009, 12:53 AM)winmutt I read an interesting bit here :
http://www.nwbombers.com/forums/index.ph...t&p=146235
Sounds like removing the shims may give additional power, I may try this out tomorrow.
If we are talking about the shims under the barrel flange, then you will change individual timing, nothing else.
Changing something directly under the DV could change the spring load of the DV piston. But it will be much easier to change the spring itself.
Please help me to understand what part we are talking about.
Tom
To do this right you need to find a willing technician. I sincerely wonder from the lopey idle if this is not the lift pump causing the problem.
The MW pump tuning docs are around,there is even a power point presentation. This requires the testing bench which involves a 10hp stepper motor and flow control.
To do this right you need to find a willing technician. I sincerely wonder from the lopey idle if this is not the lift pump causing the problem.
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