American Bosch injector phasing

I have my Super 55 American Bosh injector pump on the bench and l am following the manual to check the phasing.
I believe when the pump camshaft lines up with the pointer and the marked tooth on the head is also lined correctly it is the number 3 cylinder that is fuelled instead of number 1.
The manual dosn't go onto explain how to change the phasing. If someone can steer me I would be very grateful.
 
I am guessing that phasing to you is when you want to "flow time" the pump? When you have everything lined up you are on #1 cylinder. I will send you an e-mail. J.
 
The two marks DO NOT align at the same time when head is installed correctly. The cam tappet is set to just begin lifting at cam base circle, then head mark is aligned to install head. The cam is turned to lift plunger to Port Closing, front hub mark then aligns with pointer. At that time gear mark will have moved one tooth away from it’s installed mark. When gear mark is in window with hub mark aligned, pump is timed on cylinder one. When hub mark is aligned and gear Mark IS NOT in window, pump is on cylinder six on six cylinder pumps, or four on four cylinder pumps.
 
Thanks l understand most of that and will work through it over the next few days double checking everything.
At present when l rotate cam the hub mark aligns when number 3 port not 1 or 4 closes.
John
 
Might be you have the wrong head assembly that has a different head gear, what is the head number? I'll try and see what you have, might be a Case or MM PSB head..
 
Thanks again.
I have gone over the details you outlined. The sequence now is as follows.
As the hub mark and pointer align the marked head gear tooth is one tooth past arrow and my number one port has begun to open.
I hope this is correct.
In my head this is happening 26 degrees before TDC?
Again thanks John
 
When the hub mark/pointer align is PORT CLOSING. That is found on PSB pumps by removing the delivery valve and spring. With cap in place, throttle set wide open, low pressure or three foot gravity can used, fuel will flow from number one outlet. When drive hub is turned to align mark with pointer flow should just stop, PORT CLOSING. With tappet wear on older pumps hub mark might go past the pointer slightly. Port closing means the plunger has risen high enough to close off the inlet port and then trapped fuel above the plunger is ready to be forced to the injector. The metering sleeve location determines when injection stops by opening the plunger hole. Metering sleeve MUST be at full load for accurate port closing check, if sleeve is in no fuel position port closing can't be found. Where the hub mark aligns in relation to flywheel is engine builder spec, usually 25-35 degree range.
 
Okay
I have been over the pump again, tappet just barely beginning to lift, head mark aligned, operating lever back, rotate cam and fuel just begins to flow as mark and pointer align and head tooth mark one tooth past.

Everything seems correct except port is opening not closing.
 
“ I've seen Oliver pump hubs have the plate slip on the hub before too.”

Yes, that happened to the pump on my fleetline 88.
 
Yes, the flow stops as you rotate it past the hub mark clockwise, just as it spins forward.
If the plate has moved on the drive hub how could it be in register with head and with the tappet?
I will look at the drive hub l wasn't aware it was two piece, is it a press fit?
Thanks a lot John
 
Plate with timing mark is a pressed/crimped fit, they have been known to come loose. If flow stops within 1/8-1/4 inch past the pointer I'd more suspect tappet wear/pin/roller wear..
 
Hello yet another message about my pump. Thanks for all your help so far l hope this isn’t getting tiresome.
I am still at a loss to understand how the port opens when it should be closing.
I checked the drive hub and it looks perfect.
My observation is the plunger begins to lift when the hub mark is 1/2 inch before the pointer and they align when my port opens and when the port closes the hub mark has turned approximately 45 degrees clockwise and the plunger starts to return down.
Thanks John
 
You say the flow stops as the hub mark is just slightly past the pointer? That's NORMAL with a slightly worn tappet, and flow WILL stop again when tappet is on it's way down and head gear turns the plunger far enough the plunger slot is no longer in register with that outlet. Forget about PORT OPENING, it's NOT used on PSB pumps anyway. Port opening is ONLY used on some inline pumps with variable begining/constant end of delivery plungers.
 
In straight forward description the flow of fuel begins as the hub mark is at the pointer it stops flowing about 45 degrees past the pointer.
Which is a long way past. The manual says the pump is assembled incorrectly if it is out by 3/8 inch.
 
Something is really wrong, is the throttle wide open, metering sleeve in UP position where it NEEDS to be to check Port Closing? Remove BOTH fuel inlet ant outlet fittings, use a bright light while looking through that port. When the plunger is lifted with the cam hub the pointer should align with the hub just as plunger top CLOSES the port. Either the metering sleeve is DOWN, or wrong head is in the pump, or head installed wrong. That's why I asked for the head number.
 
The head number as l can make out is 3208 the body is PSB 4A serial is l think TB 63928. The body also has been stamped Z90. The tractor ran when l got it and l drove it a short distance it ran well enough. l had an injector mechanic look at why it bled fuel into the sump that problem he sorted but it has never run again. I have time tomorrow to check the plunger and metering sleeve as you outlined.
John
 
I am feeling confused. I ran through the internal timing again and it was perfect. Then observed the plunger rising with the bright light, when the light blacked out the hub pointer was bang on the mark. I then ran the gravity fuel test and fuel still BEGINS to flow precisely when hub and pointer line up.
The control arm is back and the sleeve arm moves back although the travel isn't a lot. On a clock face the sleeve arm travels say from 8 o'clock when it is down and about 4 o'clock when it is up.
John
 

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