Pump Questions

[Demon Dodge]

I finally put my PW injectors and 16cm turbo on also had to change the head gasket because it was weeping coolant. The head bolts seemed to be real loose especially when compared to tightening torque.

The new power is fantastic it feels like a new truck but i just bought a bigger trailer for the race car and I want even more power so here are my questions.



1. What should the pump be timed at? I'm leaving for Oregon Tuesday and my buddy has the gauges to set it. I already verified TDC when I had the head off.



2. I downloaded the pump adjustment pages from Fritz's web site, but wasn't sure if iI should adust the pump before or after setting the timing. What do you guys think?



3. Just driving around town with hardly any load I can bounce the boost up to 20 psi it should go higher with the camper and trailer on it is this about the average boost pressure?



Thanks Guys this is a great Web Site

Rod

 

[Matt S]

I would adjust the pump now and tweak as necessary later. It is free. I see about a 3-4 lb gain on a hard pull with a load compared to empty.

 

[Demon Dodge]

Come on guys, I know you all have some opinions on this. I just got back from Oregon and I need to pump this engine up. I need more power on the hills. MY buddys 95 ran away from me and hid. With the PW injectors and 16cm turbo power is up and mileage didnt change so I need to take this a step further.

What timing should the pump be set at and what effect does it have on EGT?

 

[Jim Curry]

OK Demon Dodge;



There have been a number of different settings that are being used. Stock setting has been reported to be appox. 1. 25mm above TDC. I have seen recommendations anywhere from 1. 4mm above TDC to !. 7mm above TDC. You can go to the trouble of taking things apart to the point that you can set the pump exactly to a new value using dial-in gauge etc. which takes a lot more work but is the only way to know for sure what you are set at. The quicker less involved and less accurate way would be to mark your current pump position with a scribe line (do this in any case) loosen the three or four bolts that hold the pump to the front casing and rotate it up toward the engine a small amount. Say 1/8 inch give or take. You may or may not have to loosen the six fuel lines coming into bottom of pump to be able to rotate pump. Be sure to tighten them up nice and snug after. You don't want any leaks. Ted Jannetty Recomended to me a timing of 1. 45mm. Take top cover off pump and remove diaphram. Turn star wheel all the way down clockwise and then back the other way about 2 turns. replace diaphram keeping in mind to look at the shaft or pin that the diaphram is attached to. Notice that the shaft has an eccentric shape to it. Place the shaft and diaphram assembly back into position keeping the eccentic facing the front of the truck. That is to say put it in so the most indented portion of the pin is towards the rear of the truck so there is as much open space between the front of the pump and the appex of the eccentic as possible. Bolt it back togeather and take her for a ride.

Sorry for the long post and I hope I explained things clearly.



Have fun Jim Curry



PS: There are some specialty wrenchs that you will need to be able to get to some of the bolts that bolt pump to front housing as well as some of the fuel lines going into bottom of pump if it turns out those must be loosened as well.

 

[Scot]

Originally posted by Jim Curry

OK Demon Dodge;



There have been a number of different settings that are being used. Stock setting has been reported to be appox. 1. 25mm above TDC. I have seen recommendations anywhere from 1. 4mm above TDC to !. 7mm above TDC. You can go to the trouble of taking things apart to the point that you can set the pump exactly to a new value using dial-in gauge etc. which takes a lot more work but is the only way to know for sure what you are set at.

How is this related (or is it) to setting plunger lift values also called pump timing as shown in the Cummins manual? And should I request anything off OEM spec on my rebuild?

 

[Jim Curry]

Setting timing off of TDC is Using TDC as reference point to set pump timing. To set pump timing weather against the reference point of tap dead center for an exact setting or by "guessing" and just rotating the pump, rotating the pump is how the timing is set regardless. The timing will change the same amount and have the same result (appox) weather you do it from tap dead center or not. If you use the guessing method you are doing just that. The difference between 1. 25mm Above TDC and the Highest recommended setting that I have seen of 1. 7 is only a difference. 45mm or not quite 1/2 of a mm. I/8 of an inch movement is acctually a high side figure. A range of 1. 4 to 1. 7 probably runs more around the 1/16 of an inch give or take. This is a trial and error meathod and is only offered as an alternitive to the proper way to set it exactly for someone who may not have the time and or tools to do it to the exact setting.



Jim

 

[JFitzgerald]

Jim Curry, What results did you see from setting pump timing the "less involved" method, and setting the star wheel as you described? Thanks.

 

[Jim Curry]

ISet the star weel in this way according to instructions from deisel dynamics when they still offered products and info for first gen trucks. Big improvement in HP and turbo boost. However i did do these adjustments at the same time I added my 16 cm housing. I went from 18 -20 lbs of boost to about 22 to 24 lbs of boost. At that time I must assume that part of that gain was due to the pump adjustments and some to the housing. After turning the pump fuel screw up I went to 24 to 26 lbs boost. (very modest adjustment. )Then Added 215 HP injectors and went up to 29 lbs of boost. Just adjusted timing by guess method for the first time the other day and I am still in the process of evaluating the initial results. So far I have noiticed the truck runs a little smoother, I have seen an increase in idle speed of 50 to 100 rpm,( it tends to vary a little probably due to a/c compresor cycling). Have only gone about 150 to 200 miles since adjustment so I will have to let you know how things are going as I notice the results for mileage, performance, etc... Also may adjust in and out ( probably out) to try to zero in on the best setting. A friend of mine owns a diesel shop and has the right tools to reach all of those hard to reach bolts and from experience tweaked it a bit for me at no charge. So I could not pass on the opportunity.



Jim

 

[drives mopars]

my pump

my 93 was taken off by a shop in stockton ca

they told me a lot would increase, it did not

they did not do much, i have 14 cm hse,

pw's bigger exaust, was at 213 rear tires

on a dyno in vegas, today went to sacramento

imler ? diesel (ken) dyno day, 1st off he adjed

pump screw a little hp was 197 on mustang dyno

compare that to 213 b4 a little pump adj, they he turned it a little more hp today 213 on mustang

a new 2001 hp was at 188 b4 i was equal to a 2001

hp in vegas dyno said 200-215, so i picked up

almost 20 hp today , runs a lot better in od 5th



so iam at about 90 hp more than stock at rear tires, fly wheel hp is about 330



a 2x4 3/4 ton was at 250 hp so iam loosing

morein 4x4 and dually ,



a real good guy to call is bruce at pittsburg

diesel, bill

 

[BushWakr - RIP]

Originally posted by Jim Curry

OK Demon Dodge;



..... That is to say put it in so the most indented portion of the pin is towards the rear of the truck so there is as much open space between the front of the pump and the appex of the eccentic as possible.



Have fun Jim Curry



Jim, I think you may have misspoken, or I'm confused.

Isn't the 'indented portion' of the cone facing the front?? I understood that the fuel delivery pin which rides on that eccentric cone should be as far out as possible right from the start. That would provide max. up-fueling rate. (???) Sorry if I'm off base here.

Here's the URL of a thread which shows a pretty 'sorry' (I did the pic) sketch of the diaghram/cone/pin etc.

https://www.turbodieselregister.com/forums/showthread.php?threadid=22290



Regards, Bob

 

[BushWakr - RIP]

Originally posted by Jim Curry

OK Demon Dodge;



..... That is to say put it in so the most indented portion of the pin is towards the rear of the truck so there is as much open space between the front of the pump and the appex of the eccentic as possible.



Have fun Jim Curry



Jim, I think you may have misspoken, or I'm confused.

Isn't the 'indented portion' of the cone facing the front?? I understood that the fuel delivery pin which rides on that eccentric cone should be as far out as possible right from the start. That would provide max. up-fueling rate. (???) Sorry if I'm off base here.

Here's the URL of a thread which shows a pretty 'sorry' sketch of the diaghram/cone/pin etc.

https://www.turbodieselregister.com/forums/showthread.php?threadid=22290



Regards, Bob

 

[Jim Curry]

Perhaps I did not word it well but that is what I ment as well . the fuel pin that pops out from the front side of the pump closest to the frornt needs to have as much room for travel as possible.



Jim Curry

 

[Rockcrusher]

Originally posted by Jim Curry

OK Demon Dodge;



There have been a number of different settings that are being used. Stock setting has been reported to be appox. 1. 25mm above TDC. I have seen recommendations anywhere from 1. 4mm above TDC to !. 7mm above TDC. You can go to the trouble of taking things apart to the point that you can set the pump exactly to a new value using dial-in gauge etc. which takes a lot more work but is the only way to know for sure what you are set at. The quicker less involved and less accurate way would be to mark your current pump position with a scribe line (do this in any case) loosen the three or four bolts that hold the pump to the front casing and rotate it up toward the engine a small amount. Say 1/8 inch give or take. You may or may not have to loosen the six fuel lines coming into bottom of pump to be able to rotate pump. Be sure to tighten them up nice and snug after. You don't want any leaks. Ted Jannetty Recomended to me a timing of 1. 45mm. Take top cover off pump and remove diaphram. Turn star wheel all the way down clockwise and then back the other way about 2 turns. replace diaphram keeping in mind to look at the shaft or pin that the diaphram is attached to. Notice that the shaft has an eccentric shape to it. Place the shaft and diaphram assembly back into position keeping the eccentic facing the front of the truck. That is to say put it in so the most indented portion of the pin is towards the rear of the truck so there is as much open space between the front of the pump and the appex of the eccentic as possible. Bolt it back togeather and take her for a ride.

Sorry for the long post and I hope I explained things clearly.



Have fun Jim Curry



PS: There are some specialty wrenchs that you will need to be able to get to some of the bolts that bolt pump to front housing as well as some of the fuel lines going into bottom of pump if it turns out those must be loosened as well.

What are the specialty wrenches for the high pressure fuel lines at the pump? I just changed out my injectors and fortunately didnt have to remove fuel lines, but may be pulling pump next for overhaul.

 

[Jim Curry]

The most noticable specialty wrenchI saw was a curved wrench which was used to loosen 1 or 2 of the back bolts that attach the pump to the front housing to allow the pump to be rotated to set timing. With out this curved wrench it looked to darn near immpossible to get to those back bolts. He also had to loosen all six of the fuel lines coming fromthe injectors at the bottom of the pump. Although some of these lines are hard to get to I do not remember for sure wheather he had any special wrenchs for these connections or just used several different length wrenches depending on the clearence available.



Jim