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4bt Ve pump timing gear marks

78K views 33 replies 11 participants last post by  scout4bta 
#1 · (Edited by Moderator)
I bought a core 4bt that was taken apart so the previous owner could rebuild it. He lost interest and sold it to me and I had it rebuilt. My question is how to time the pump.

I found out how to time the cam with no problem but found a few different ways to time the pump gear. The ve pump that came with it but was not used on it is an automotive type but has no ksb on it. On my pump gear there I a GD EC and a little over a 180* from that is FBHA. I found some people use G as their mark and found that others use B from what I can tell from the pictures.

So my question is what is the RIGHT timing mark? Here is a pic of all the numbers stamped in it if they're needed for the correct timing marks
 

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#2 ·
Does your VE pump have a woodruff key on the input shaft? If so, timing should be easy. Put the motor at TDC using the timing pin located just below the injection pump on the timing cover. Next, mount the injection pump on the timing gear housing and take a look at your CAM gear. The 0 should be pointing directly at the injection pump input shaft. Install the injection pump gear with the woodruff key and line up the "F" on the IP gear with the "0" on the CAM gear. Torque IP nut, reinstall timing cover and you're good to go.

I do not know what timing offsets are each of the other letters on the IP gear, but "F" is what my motor was set to by Cummins when it was reman'd, so that's where it will stay.

Some pictures of my motor:





For reference, this is the injection pump I have:



 
#3 · (Edited)
Yes my ip does have the wood druff key.. Thanks for your help I'll set it up like you said
My next question is where do I set the pump timing? Line up the line on the pump and on the timing cover ?
Thanks for your help!
 
#4 ·
No problem!

I do not know how to set the rotation of the IP on the timing gear housing. I set mine slightly advanced from where it came to me, as shown by the paint lines :D

I can take a look and see if there is an index on my motor later today and let you know.
 
#5 ·
If it were me I would pay a small sum and have a pump shop time and lock the pump. Then install the pump per the factory procedure. That way you can be 100% sure you have an accurate starting point if you ever want to tweak it in the future. Its much MUCH easier to do it now before the engine is installed.
 
#6 ·
Casey, good point. That's a good idea.

I haven't had a chance to see if there is a reference on the timing gear housing. I'll do my best to check today after work.
 
#7 ·
I bought a core 4bt that was taken apart so the previous owner could rebuild it. He lost interset and sold it to me and i had it rebuilt.My question is how to time the pump? I found out how to time the cam no problem but found a few different ways to time the pump gear. The ve pump that came with it but was not used on it is a automotive type but has no ksb on it. On my pum gear there I a GD EC and a little Over a 180* from that is FBHA. I found some people use G as there mark and found that others use B from what I can tell from the pictures. So my question is what is the RIGHT timing mark? Here is a pic of all the number stamped in it if there needed for the correct timing marks
Because the pump did not come on the engine the marks on the cover and mark on the pump do not correspond to any known value. The propper way to time it would be by plunger depth at TDC and in that case the only differance between using F or B on the pump gear would be how far the pump would be from the head when set. F would be closer to the head than B at the same plunger depth settings at TDC.
 
#8 ·
Hold the phone, I remembered something important about the VE IPs. When I had my pump calibrated, my pump shop told me that because the 4 cylinder IP hits TDC every 360 degrees, that there was a casting mark on the nose of the IP that shows you where TDC is. Pictured below, you can see the woodruff key lines up with the mark on the IP nose, right above the seal, indicating that the pump is at TDC.

Therefore, the process would be:
1. Pin the motor at TDC with the cam gear installed
2. Pin the IP at TDC
3. Install the IP in the timing cover, with nuts loose so the IP can rotate
4. Install the IP gear on the IP and line up the timing mark with "F" or "B" , as dieseldude explained in the post above
5. Once the timing marks are lined up, tighten down the 3 IP mounting nuts and release the pin from the IP

Doing this keeps your IP and motor at TDC while the IP is being installed. This is what I did when I installed my motor and I've been running great for a year.

Clear as mud?



VE TDC pin location:



 
#29 ·
The letters were different on my motor but the process was the same
I installed the pump at F as suggested but I never had the gear off. Timing cover pump and all swapped from one motor to the next. The timing was off. After removing the timing gear the woodroof key was lined up with the scribe mark on the pump and locked. The gear was then installed where a different group of letters lined up perfectly. The truck fired up in two cranks. Thanks for the help! Line up the woodroof. Lock the pump. Find a near by letter. You may need to clock the pump for fine tuning.
 
#9 ·
Pumps are not installed at TDC. They are set at a specified plunger depth before TDC on the pump.
Get a service manual and the tool and set them correctly takes all the guessing out of it.
 
#10 ·
Like Dieseldude stated get the pump timing tool. Everything else is just a guess. There are enough variables that effect injection timing outside of injection pump camplate lift at TDC. If you can't measure timing your just guessing and can waste a lot of time that way.

The timing tool is just a metric dial indicator that mounts in the distributor head. You zero the indicator with the pump rotor full forward and continue turning the engine over until you reach #1 TDC. The indicated rotor position (camplate lift) is the timing position. The number on the engine ID plate is the factory timing position. Rotate the pump to achieve the desired timing.

Mild VE motors like 1.6 to 1.7 MM base timing with most common piston/nozzle combinations and the paper thin injector washers.

If you don't measure the timing you're not going to be very effective tuning the engine.

It helps to make some easy to read painted on timing parts on the front of the engine.
 
#11 ·
Not saying y'all are wrong, but I installed my IP as pictured (without measuring static timing via timing tool) and it's been great for the past year.

With what you've explained, would this be an accurate process?

1. Pin the motor at TDC with the cam gear installed
2. Pin the IP at TDC
3. Install the IP in the timing cover, with nuts loose so the IP can rotate
4. Install the IP gear on the IP and line up the timing mark with "F" or "B" , as dieseldude explained in the post above
5. Install timing tool (dial indicator) on the distributor head to verify / fine tune static timing
6. Once timing is set, tighten down three IP nuts and install fuel lines.
 
#12 ·
If you line up the cam mark with the "F" on the IP gear you can move the VE pump through the full 10 degrees of adjustment the slots in the pump provide and the engine will start and run OK.

When I hear "I just bumped the timing 1/8 inch". I always wonder how many people before them bumped the timing 1/8"? The marks on the timing cover mean nothing unless you are 100% certain nothing has ever been changed since the engine was assembled at the factory and even then your eyeball is not very good at lining those marks up, especially with the perspective you get installing a pump under the hood. A lot of guys think those marks are important and will re-stamp them when they change the timing.

These are really simple engines. They're tolerant of mis-adjustment.

VE pumps don't pin at TDC. They just have a shaft lock bolt. A large percentage of them don't even have that lock bolt. It's not needed, but it does help to lock the shaft when lining up the woodruff key with the keyway in the gear.

The procedure would be to put the gear in the timing housing lined up with "F" as "F" is the most advanced factory setting, you will see the best range of adjustment from the pump with the gear installed at "F". You put the pump on the engine, torque the gear nut, leave the 3 nuts to the timing cover just loose enough that the pump can rotate, but cannot wiggle (if the pump can wiggle your measurements will be off). Remove the distributor head plug, install the timing tool and rotate the engine until the indicator reads it's lowest. Zero the indicator. Now turn the engine to #1 TDC. Rotate the injection pump to the desired timing. Tighten the pump down. Remove timing tool, Connect lines, bleed, etc.
 
#14 ·
Awesome info right here. Thank you sir :beer:


What timing tool would you advise for timing the pump? Does Bosch make a tool, Cummins, or is there a good off-the-shelf tool that works?
 
#13 ·
the letter on the gear corresponds to the emissions and the year and type of the pump.
B is for 4bt ve pumps prior to 1987 and F is for 4bt VE pumps after 1987.

Since yours has a cold start solenoid on it, I would use the letter F on your setup.
There is a chart for which pump and letter to use in the cummins manual.
 
#16 ·
What about A ve pump with no ksb? That is what I have
 
#15 ·
Got mine from Cummins but I bet others make them as well.
 
#17 ·
if I had to guess then I would say B
 
#18 ·
Thanks. I took my IP to a diamond diesel where my buddies uncle works and he's going to make sure it puts out like its suppose to since I not a 100% sure it's even a good pump. And if it tests out good he'll time it

Thanks for everyone's help
 
#19 ·
I would like more information about the specifics of using alignment other than "F". I've been into many VE pumps and am aware of the differences between KSB and non-KSB pumps, but never noticed any difference in base timing position or camplate position between the two?

The woodruff key in the VE shaft lines up with the same spot on the rotor in every pump (or so it appears).

I started using the timing tool and it really opened my eyes to how much very slight pump movements effect pump timing. It's not that hard to use, especially when assembling a new engine and saves lots of time in the long run.
 
#20 ·
I have an engine apart right now and am changing it to a VE pump and noticed that the manual had both F and B as timing marks for 4bt's.
While looking at it I noticed that if the pump is locked at say 1.6mm and set at F mark it is closer to the head than the same locked pump set at the B mark.
So if you use the B mark you have more room for advancing the pump or more room to get to idle adjustment at the same mm depth than one using the F mark.
Does this make sense?
 
#21 ·
If the engine has been apart before by someone else than the present owner then be careful assuming #1 is at TDC when the engine is pinned. The pin retainer has slop in it and if it was removed then #1 has to be actually set at TDC before the pin is engaged and then the pin retainer is tightened down. #1 can be checked for TDC with a tool in the #1 injector hole or with a screwdriver if you are really careful.
 
#22 ·
I always use the valve drop method to determine TDC then I know it is accurate.
 
#23 ·
I use a piston stop thru the #1 hole and a degree wheel. Rotate the engine CW until it hits the stop, note degree wheel reading. Rotate engine CCW until it hits stop, read degree wheel. Divide total degrees between both points by two and that is TDC. Absolute accuracy.
 
#24 · (Edited by Moderator)
That's what the valve drop does, you're just using an exhaust valve and a pointer instead of a piston stop in an injector hole and a degree wheel.

Drop Valve Method to Find TDC
 
#25 ·
Neat. I assume you tape a plastic tape to the damper to get the exact midpoint for TDC? Put a paint mark on the pulley and good to go for future adjustments.
 
#26 ·
No, the pointer is just a wire on a bolt so every time you do it you must go through the whole procedure.
 
#27 ·
Fab a heavy duty pointer from 1/8" and have it bolt to two timing case bolts, not going anywhere.
 
#30 · (Edited)
So I've been posting this in the general tech section but thought I'd seek more advice. Trying to get a used 5.9 VE pump engine running. Guy who sold it to me seemed like a good dude, I didn't doubt him when he told me it ran when he pulled it but... been having some serious trouble getting it going.

I'm going to copy/paste my posts.
Bruke,

Here are a few pics for the Cummins manual .
1. Here is the hash marks for the cyl and 6cyl .
2. Cam gear dot to pump gear letter.
3. some info .
So this is all you need to do to put the pump in time, line the keyway up with a mark on the front of the pump just under the seal?

I've got a used motor and while I thought it was stock it would seem someone way advanced the timing or something. I killed the KSB and rotated the pump CCW and I can get it to run but just barely at full throttle, lots of smoke and such. Almost positive timing is WAY to advanced.

Going to pull timing cover to check marks and then may end up pulling pump to make sure it's timed right as well. If I don't find a problem I will have injectors tested.

Also deleting fuel heater to make sure I'm not sucking air in through the filter/heater. It IS leaking fuel out the throttle shaft at a steady rate but I bought a bushing and o-ring to replace that as well.

Still thinking way advanced timing.

(no exhaust piping yet)
instagram. com/p/tEuDfaswfQ/

Edit: I understand the whole plunger depth deal but just for roughing it in this is how you do it?
Okay, got the parts to fix a few things so I'll chase all that down and report back.

It didn't want to run hardly at all, would just cough and cough and cough. I unplugged the KSB, which should have retarded the timing some, and that helped. After that I rotated the pump head away from the block which also should have retarded the timing and that was enough to get it to fire but just barely at full throttle. I do get squirting fuel to all 6 injectors. Lots of black smoke when it runs. I posted a link to a video on instagram of it running like that but this site isn't happy with me posting links yet so I had to segment the link.

In talking to Industrial Injection while ordering parts he was under the impression the pump would not suck air from there but only push fuel out if leaking. I'll get it fixed and see what happens anyway. I know when bleeding some of the lines I was getting bubbles but I also suspect my fuel heater is leaking. Got parts in to delete that so I'll get that fixed and check out the key way and report back.

I appreciate your help!
Rotated the engine until plastic pin popped in, confirmed that rockers at #1 had play. Pump gear keyway at about 7 o'clock. Couldn't quite tell if I was seeing a key or just a shoulder on the shaft. Was able to stick a 45* pick in there a ways. Shaft turned with gear with engine. Shaft had some in and out play.


Fixed fuel leak, deleted fuel heater, runs the same.

Cracking injector line nuts yields a good spray, comparable to any others I've bled.

Assuming timing is still my issue.

Thanks Scott. Just wanted to make certain that it's not correct. Can't imagine what could have happened. Will pull timing cover and see if it was set up wrong or if key sheared.

Guy I bought it from said it ran when he pulled it, maybe he pulled the pump for some reason. Seemed like a stand up guy, don't like to think he may have lied. Either way it needs fixed...

Thanks for the help!

-Max

Here's a video of it running, just barely, full throttle. Anyway I'm sure that must be the main issue.

http://instagram.com/p/tEuDfaswfQ/

Can't embed apparently.
I might have mentioned this is on a 1st gen 5.9 cummins, pulled timing cover, set engine to TDC #1, play at rockers, timing gear marks all line up, pump gear at factory 'E'. Keyway at 7 o'clock roughly. Lines up with mark on pump face. I turned the pump through a couple of rotations. I hope that was not ill-advised. As I turned it, it would click, like a sprag, I assume that's normal.

http://www.4btswaps.com/forum/showth...l=1#post105335

Wish I had seen that earlier or mentioned it's a 6 cyl!

Thoughts?







So TL;DR -- trying to get used 5.9 to run, seemed way advanced -- checked with a couple other diesel mechanics -- thought my timing was off, retarded timing and I can get it to barely run, checked timing and it would APPEAR that it's correct, roughly.
 
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