P7100 Pump timing.

Has anyone tried spill port timing on p7100 verify timing. Maybe you can tell me if I’m doing something wrong.
Took the delivery valve out. Gutted the delivery valve holder. Installed the delivery valve holder back on pump. Moved the shut off lever to run position and throttle lever to full throttle. I pump the hand primer while my brother turns the motor over slowly. My problem is that the stream of fuel coming out the the line stays stead never slows down to a drip. Has anyone seen this before is there something I’m doing wrong.

Thankyou Jake
 
Depending on the type of plunger, you need to be at certain rack travels to get correct spill timing. I believe that pump has retard notch plungers (like a 215), so the plunger needs to be in the middle of travel roughly to get the correct reading. It should cut in any position other than shutoff however. Did you leave the delivery valve body in and take the center of the valve out? If you took the whole valve out it will flow continuously because there is bleed holes in the barrel where the delivery valve goes.
 
Thankyou that makes since. I took the entire delivery valve out. I seen the bleed holes in the barrel looking at the top of my plunger I looks like it is cut for a retarder.
 
This is the 4bt pump you are trying to time? or the 96 dodge? I saw both in the thread so I wasn't sure. Anyways try it again with the valve body still in and see what happens.
 
Yotadzl said:
This is the 4bt pump you are trying to time? or the 96 dodge? I saw both in the thread so I wasn't sure. Anyways try it again with the valve body still in and see what happens.
Click to expand...

Yes this is a pump on the 4bt. Bought the pump used and don’t know any of the info on the pump. So I’m trying to verfy the timing. I have the dial indicator and the adapter but there are so many different measurements for lift and different degrees of timing i figured this would be the best way to find out what I have.
 
Yotadzl said:
I believe that pump has retard notch plungers (like a 215)
Click to expand...

If the pump is set up correctly (by someone knowing what they are doing) the upper helix notches found in the 215hp & some other pumps can advance timing as much as 6 deg’s. But yes, in stock factory form the pump would retard timing as it never gets past 14mm of rack travel.
 
Nascar said:
If the pump is set up correctly (by someone knowing what they are doing) the upper helix notches found in the 215hp & some other pumps can advance timing as much as 6 deg’s. But yes, in stock factory form the pump would retard timing as it never gets past 14mm of rack travel.
Click to expand...

That is Bosch terminology for a notch or helix cut on the leading edge of the plunger. It varies start of injection. Because it is recessed from the top of the plunger it can ,in effect, ONLY retard injection timing. Timing is set in the middle of the notch so you have a minimum amount of static advance. On either side of the notch it will advance from the MINIMUM spec of static timing. But the top (leading edge) of the plunger is not variable, and the notch effectively retards timing, hence retard notch.
 
So when I spill test I want to be at 1/2 throttle? I kinda did a half a spill test with delivery valve out i turned the motor over till i could see the plunger cover the inlet hole. But I did that at full throttle. I should put the inlet hole at the lowest point of the plunger if I understand right.
 
Throttle doesn't directly relate to plunger position. With the delivery valve out so you can see the top of the plunger you want to line up the lowest part of the top of the plunger with the holes in the barrel. That should get you really close. Then try and hold the throttle in that position while you do the spill timing. Just make sure the plunger is traveling up and the pump is turning clockwise when you do the spill timing.
 
Yotadzl said:
That is Bosch terminology for a notch or helix cut on the leading edge of the plunger. It varies start of injection. Because it is recessed from the top of the plunger it can ,in effect, ONLY retard injection timing. Timing is set in the middle of the notch so you have a minimum amount of static advance. On either side of the notch it will advance from the MINIMUM spec of static timing. But the top (leading edge) of the plunger is not variable, and the notch effectively retards timing, hence retard notch.
Click to expand...

lol. Nope. You are following the internet blanket myth of the 215 retard notch that only can retard. As mentioned, when set-up by someone that knows what they are doing, the 215’s can advance 6 degs. Seth builds most of the pumps I sell nowadays & before that I marketed the PDR Stupid Pump that guys like Fletcher, Scott Vorhee’s Big Bad Dodge etc put up the numbers back in the day.

Some info quoted by Seth:

"If the pump is pinned at 10.5mm rack travel, which lands at the lowest (flat) part of the upper helix. So when we pin the pump at 13* btdc and it is set on the engine at TDC, this is how the rack travel equates in static timing on the engine (dynamic follows closely too)
0 to 5.5mm- no port closure
6.0mm- 16.5* btdc
6.5mm- 15.5* btdc
7.0mm- 14.5* btdc
7.5mm- 14* btdc
8.0mm- 13.5* btdc
8.5mm to 16.0mm- 13* btdc
16.5mm- 13.5* btdc
17.0mm- 14.5* btdc
17.5mm- 15* btdc
18.0mm- 16* btdc
18.5mm- 17* btdc
19.0mm- 18* btdc
19.5mm- 18.5* btdc
20.0 to 21.0mm- 19* btdc

In factory form, the pump never gets past 14mm, so it only retards timing, that may be where the internet theory came from. With a stock rack plug, it only achieves 19.5mm rack travel. The way I set them up when I max/balance them they reach the 6* advance right at 21mm and no less.

0 to 10.5mm of rack travel, not idle to half throttle. Those are two completely different things. In stock form these pumps idle between 6-7mm, zero boost fuel is 10-11mm, and full fuel is 13.5-14.5m of rack travel.

The groove in the top of the 215 plunger lies in the middle of the plunger and comes into play in the middle of rack travel (10.5mm). In a static test, the timing is retarded as you move from 0 to 10.5mm, then it is advanced from 10.5mm to 21mm. However, static timing doesn't tell the entire story. To advance timing using the plunger, you must lower lift to port closure, which hurts high end performance more than the timing change would help."

So please educate yourself on the notch/helix & stop spreading false info that the 215 pumps & others plungers that have the notch/helix can only retard timing.
 
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Nascar said:
lol. Nope. You are following the internet blanket myth of the 215 retard notch that only can retard. As mentioned, when set-up by someone that knows what they are doing, the 215’s can advance 6 degs. Seth builds most of the pumps I sell nowadays & before that I marketed the PDR Stupid Pump that guys like Fletcher, Scott Vorhee’s Big Bad Dodge etc put up the numbers back in the day.

Some info quoted by Seth:

"If the pump is pinned at 10.5mm rack travel, which lands at the lowest (flat) part of the upper helix. So when we pin the pump at 13* btdc and it is set on the engine at TDC, this is how the rack travel equates in static timing on the engine (dynamic follows closely too)
0 to 5.5mm- no port closure
6.0mm- 16.5* btdc
6.5mm- 15.5* btdc
7.0mm- 14.5* btdc
7.5mm- 14* btdc
8.0mm- 13.5* btdc
8.5mm to 16.0mm- 13* btdc
16.5mm- 13.5* btdc
17.0mm- 14.5* btdc
17.5mm- 15* btdc
18.0mm- 16* btdc
18.5mm- 17* btdc
19.0mm- 18* btdc
19.5mm- 18.5* btdc
20.0 to 21.0mm- 19* btdc

In factory form, the pump never gets past 14mm, so it only retards timing, that may be where the internet theory came from. With a stock rack plug, it only achieves 19.5mm rack travel. The way I set them up when I max/balance them they reach the 6* advance right at 21mm and no less.

0 to 10.5mm of rack travel, not idle to half throttle. Those are two completely different things. In stock form these pumps idle between 6-7mm, zero boost fuel is 10-11mm, and full fuel is 13.5-14.5m of rack travel.

The groove in the top of the 215 plunger lies in the middle of the plunger and comes into play in the middle of rack travel (10.5mm). In a static test, the timing is retarded as you move from 0 to 10.5mm, then it is advanced from 10.5mm to 21mm. However, static timing doesn't tell the entire story. To advance timing using the plunger, you must lower lift to port closure, which hurts high end performance more than the timing change would help."

So please educate yourself on the notch/helix & stop spreading false info that the 215 pumps & others plungers that have the notch/helix can only retard timing.
Click to expand...

I'm not following internet myth. My knowledge comes from building literally hundreds of these pumps. Apparently you are a little too dense to understand what I'm saying. I am not arguing that Seth is wrong. In fact what you just posted backs up what I stated. From 8.5 mm to 16 mm is MINIMUM STATIC TIMING. 13 degrees in your post, which is close. Then I said it advances from either side of the notch, which is also shown in your post. Read what I said again, if you can't comprehend it I can get some crayons and draw you a picture. I didn't say "the 215 pump retards timing at higher rpm" like is the common myth. I simply said the plunger has a retard notch, which it does.
 
lol. Ok, we’re splitting hairs then. You said the plunger has a retard notch (yes I agree it does) but you went on to say and I quote “Because it is recessed from the top of the plunger it can ,in effect, ONLY retard injection timing"......I was making the point the plunger can adv if set up right. No need to be an idiot about it.
 
Nascar said:
lol. Ok, we’re splitting hairs then. You said the plunger has a retard notch (yes I agree it does) but you went on to say and I quote “Because it is recessed from the top of the plunger it can ,in effect, ONLY retard injection timing"......I was making the point the plunger can adv if set up right. No need to be an idiot about it.
Click to expand...



It can only retard timing. Just because timing advances from where you measure port closure doesn’t change the fact the notch retards timing from the top of the plunger. Come talk to me when you’re certified by Bosch and work on these for a living. Then we will decide who the idiot is. I’m done with this argument, I’ll get back to helping the OP with his questions.


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So just to make sure this is the top of the plunger that I should move the rack so that the lowest part of the plunger over the inlet port. Try to mark the rack position Install the gear put the delivery valve back in minus the center piece try to spt to confirm the timing.
 
So I am looking into getting an adjustable fuel plate now. And I noticed that one of the plates they offer they say it’s recommended for notched style plungers. #1210 plate Why is this. What would the style of plunger have to do with the fuel plate. I believe my plungers are notched style. They are not flat across the top anyway. Thankyou
 
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