MW pump update
MW pump update
I think I might have posted originally on another forum, but all the faces look the same here. I took a spare MW pump to a large bosch shop that has done marine work for me in the hopes of finding some bigger elements. The owner is willing to work with me on it. He checked the IH MW pump that has 10mm elements and told me the were not suitable because the cam in the IH pump has 10mm lift and our MB pump has a cam with 8mm lift. He also said he had two other donners in mind and that as time allowed he would check them out.
Bob
So I guess I dont fully understand the exact innner workings of the injection pump. How would 2 mm less lift on the cam not allow use of the 10 mm elements? I would think that less lift would just mean less fuel being pumped (working in the same sense as a regular camshaft), but apparently this is incorrect thinking?
tantank79 So I guess I dont fully understand the exact innner workings of the injection pump. How would 2 mm less lift on the cam not allow use of the 10 mm elements? I would think that less lift would just mean less fuel being pumped (working in the same sense as a regular camshaft), but apparently this is incorrect thinking?IIRC. The elements are pistions with a diagonal line cut on them, the line terminated just under the top of the "piston" and above the bottom, The delivery of the fuel is done in this line. at the bottom the fuel feeds in, the top exit is against the cylinder wall. As the piston moves up the bottom moves past the feed point and is shut off by the cylinder wall, as it reaches the top, the fuel exits out and then the cylinder plunges back down. 2mm offset is probably enough to keep the fuel from coming in or out.
tantank79 So I guess I dont fully understand the exact innner workings of the injection pump. How would 2 mm less lift on the cam not allow use of the 10 mm elements? I would think that less lift would just mean less fuel being pumped (working in the same sense as a regular camshaft), but apparently this is incorrect thinking?IIRC. The elements are pistions with a diagonal line cut on them, the line terminated just under the top of the "piston" and above the bottom, The delivery of the fuel is done in this line. at the bottom the fuel feeds in, the top exit is against the cylinder wall. As the piston moves up the bottom moves past the feed point and is shut off by the cylinder wall, as it reaches the top, the fuel exits out and then the cylinder plunges back down. 2mm offset is probably enough to keep the fuel from coming in or out.
I guess that also leads to this question: Just as custom camshafts can be ground for the engine, could a custom cam not be ground for the injection pump? Maintain a very similar profile but with a bit more ramp up leading into the point of increased lift.
tantank79 I guess that also leads to this question: Just as custom camshafts can be ground for the engine, could a custom cam not be ground for the injection pump? Maintain a very similar profile but with a bit more ramp up leading into the point of increased lift.I think the issue with any of these parts is the tolerances. I believe Myna will grind them to be more angular but other than that....
tantank79 I guess that also leads to this question: Just as custom camshafts can be ground for the engine, could a custom cam not be ground for the injection pump? Maintain a very similar profile but with a bit more ramp up leading into the point of increased lift.I think the issue with any of these parts is the tolerances. I believe Myna will grind them to be more angular but other than that....
My local shop has told me that can change the plungers/DV's/barrels and cam so that I can have extra fuel. I'll find out more details very soon as I go back to FL for a visit this weekend.
hey is this an MW??? GOing cheep if it is...
http://cgi.ebay.com/ebaymotors/_Car-Truc...240%3A1318
Strangest low-pressure pump I have ever seen on a MB IP... Was there a difference between the early and late ones?
The injection pump is a normal MW but the lift pump looks to be from a W115 300D.
I got mixed up....I meant to ask if it was a 'M' pump, cause it looked strange to me, but I guess out of the car, clean, and stripped of all accesories it looks different.
Section106 So what was the outcome, MTUPower?For about $2K they will change out the barrels and plungers, and rebuild the pump. I've posted this over at shop forum, sorry I've been in NY- working.
Section106 So what was the outcome, MTUPower?For about $2K they will change out the barrels and plungers, and rebuild the pump. I've posted this over at shop forum, sorry I've been in NY- working.
(11-16-2008, 06:09 PM)MTUPowerSection106 So what was the outcome, MTUPower?For about $2K they will change out the barrels and plungers, and rebuild the pump. I've posted this over at shop forum, sorry I've been in NY- working.
(06-06-2008, 10:34 AM)tantank79 I guess that also leads to this question: Just as custom camshafts can be ground for the engine, could a custom cam not be ground for the injection pump? Maintain a very similar profile but with a bit more ramp up leading into the point of increased lift.
(06-06-2008, 10:34 AM)tantank79 I guess that also leads to this question: Just as custom camshafts can be ground for the engine, could a custom cam not be ground for the injection pump? Maintain a very similar profile but with a bit more ramp up leading into the point of increased lift.
Hi everyone I´m new to this forum. My first post here. I been looking years to find this kind of forum so now I´m very happy
I use the 617.952 engine in my Race Land Rover, a bit strange yes, but this is my second Merc engine in a Land Rover and I´m very satisfied with it. I rebuild the engine totally, ported/polished top, external balanced, a VNT turbo, rebuild pump.
The guy/company who helped me with the pump-tweeking told me in the beginning that it wouldnt be any problem fitting bigger pump-element in my pump. He did so using 10mm elements from a six cylinder "Volvo" lorry, so far so good....When he tested the pump (bench test) it delivered 122cc (didnt remember the rpm) compared to original 55cc, sound intersting. But when during the first start up wasnt to nice, in the end we got the engine running ok, but it was black smoking even on idle, the result was tooooo much fuel. Swapping back to a orginal pump, tweeked as much as possible and the engine running nice. Now the guy has rebuilt the race pump again, but now using Mercs orginal pressure valves. Before he used the Volvo ones. As Im no expert in MW pumps I would like to hear what U think of this.
Hi and welcome,
is the guy still using the 10 mm elements?
Did you see the 8 mm element (MW) thread?
What do you mean by pressure valves? Delivery valves?
The original ones of the MW for the 617a seem to be best, at least the 2nd version of the DV.
Do you have pictures of the Volvo DVs, compared to the Benz?
How did you do the control of the vanes of the turbo?
Tom
(01-06-2009, 06:52 AM)tomnik Hi and welcome,Hi Tom. Yes the guy is still using 10mm elements, yes I mean Delivery valves. Sorry for the moment I dont have any pics on the valves.
is the guy still using the 10 mm elements?
Did you see the 8 mm element (MW) thread?
What do you mean by pressure valves? Delivery valves?
The original ones of the MW for the 617a seem to be best, at least the 2nd version of the DV.
Do you have pictures of the Volvo DVs, compared to the Benz?
How did you do the control of the vanes of the turbo?
Tom
(01-06-2009, 06:52 AM)tomnik Hi and welcome,Hi Tom. Yes the guy is still using 10mm elements, yes I mean Delivery valves. Sorry for the moment I dont have any pics on the valves.
is the guy still using the 10 mm elements?
Did you see the 8 mm element (MW) thread?
What do you mean by pressure valves? Delivery valves?
The original ones of the MW for the 617a seem to be best, at least the 2nd version of the DV.
Do you have pictures of the Volvo DVs, compared to the Benz?
How did you do the control of the vanes of the turbo?
Tom
Hi,
8 mm MW elements are available. Part number: 1 418 415 058 and 1 418 415 049.
I made 6 mm MW elements, if that is enough for you, let me know.
There are several threads for controlling the vanes. Do a search.
Normally you use a vac operated device which can be connected to your engine's vac supply. Then you can try to blow into this line with your boost line. Combined with check valves and adjustable vent ports you might be better than with your manual operated version.
What seize is your turbo?
Tom
A third option is mechanical linkage.
Credit to libbybapa of VW GTD forum.
http://vwdiesel.net/phpBB/viewtopic.php?t=10365
(01-06-2009, 07:55 AM)tomnik Hi,
8 mm MW elements are available. Part number: 1 418 415 058 and 1 418 415 049.
I made 6 mm MW elements, if that is enough for you, let me know.
There are several threads for controlling the vanes. Do a search.
Normally you use a vac operated device which can be connected to your engine's vac supply. Then you can try to blow into this line with your boost line. Combined with check valves and adjustable vent ports you might be better than with your manual operated version.
What seize is your turbo?
Tom
(01-06-2009, 07:55 AM)tomnik Hi,
8 mm MW elements are available. Part number: 1 418 415 058 and 1 418 415 049.
I made 6 mm MW elements, if that is enough for you, let me know.
There are several threads for controlling the vanes. Do a search.
Normally you use a vac operated device which can be connected to your engine's vac supply. Then you can try to blow into this line with your boost line. Combined with check valves and adjustable vent ports you might be better than with your manual operated version.
What seize is your turbo?
Tom
Right, these are short stroke high-revving engines. If you want lots of torque, Cummins is always the best bet.
(01-06-2009, 07:06 AM)sweden But Im not happy with the VNT turbo. I can controll the movement of the vanes from inside of my truck, but its very very difficult got get the right setup. To much boost pressure and the exausts doesnt escape, to little boost pressure and exauts gases get to hot and lack of power.....sorry for bad spelling.Was the CDI turbo electric or vacuum controlled. A few people have used the VCV in reverse to control the vac pods. This is how I was planning on going about it.
(01-06-2009, 07:06 AM)sweden But Im not happy with the VNT turbo. I can controll the movement of the vanes from inside of my truck, but its very very difficult got get the right setup. To much boost pressure and the exausts doesnt escape, to little boost pressure and exauts gases get to hot and lack of power.....sorry for bad spelling.Was the CDI turbo electric or vacuum controlled. A few people have used the VCV in reverse to control the vac pods. This is how I was planning on going about it.
(01-06-2009, 10:23 AM)winmuttHi Rolf,(01-06-2009, 07:06 AM)sweden But Im not happy with the VNT turbo. I can controll the movement of the vanes from inside of my truck, but its very very difficult got get the right setup. To much boost pressure and the exausts doesnt escape, to little boost pressure and exauts gases get to hot and lack of power.....sorry for bad spelling.Was the CDI turbo electric or vacuum controlled. A few people have used the VCV in reverse to control the vac pods. This is how I was planning on going about it.
Perhaps you could start a new topic and shows us what you have?
-Rolf
(01-06-2009, 10:23 AM)winmuttHi Rolf,(01-06-2009, 07:06 AM)sweden But Im not happy with the VNT turbo. I can controll the movement of the vanes from inside of my truck, but its very very difficult got get the right setup. To much boost pressure and the exausts doesnt escape, to little boost pressure and exauts gases get to hot and lack of power.....sorry for bad spelling.Was the CDI turbo electric or vacuum controlled. A few people have used the VCV in reverse to control the vac pods. This is how I was planning on going about it.
Perhaps you could start a new topic and shows us what you have?
-Rolf
I use my VCV exactly as it would work with the automatic transmission.
(01-06-2009, 10:30 AM)sweden Turbo pressure-house and exaust-house are from the 320cdi, the "vanecontroll unit" are operated by pressure (7,5psi)The stock CDI turbo come with a CAN controlled actuator, but it looks like those so inclined could fairly easily modify it to be mechanical.
(01-06-2009, 10:30 AM)sweden Turbo pressure-house and exaust-house are from the 320cdi, the "vanecontroll unit" are operated by pressure (7,5psi)The stock CDI turbo come with a CAN controlled actuator, but it looks like those so inclined could fairly easily modify it to be mechanical.