P38 2.5 Inj Pump modulation issue.

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Given the OP is using a garage I imagine they're using some sort of generic reader.

Well whatever it is must be capable of syncing security code into BECM from engine ECU. Doing the static timing is a very simple task but it has to be done correctly.
 
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Hi,
OP , were you able to sort out the timing issue? how did you do it?
After standing over the garage when they asked me to "witness" them timing it (I had the instructions in my hand) The engine ran OK and the modulation sits mostly at 45-50% sometimes going outside that range. Next project is to change the timing chains as they rattle like a bag of bolts.
 
If they have never done this job before they must follow the correct procedure for pin location and timing set up using a DTI. There are two timing pips, one 40 degrees before the TDC pin hole and one 20 degrees after it. It is easy to get hung on one of those which will put static miles out. With the pin correctly inserted the engine should be immovable in either direction. The pump is set to 0.9 mm cam lift after having followed correct procedure for zeroing DTI and then inserting timing pin.
Depending how much you have stripped off the engine,there is a timing mark on the timing cover that aligns with the crank pulley to give you TDC.I used this because the hole for the locking pin was rusty. A bit of penetrating oil and a gentle tapping located the pin.
 
Depending how much you have stripped off the engine,there is a timing mark on the timing cover that aligns with the crank pulley to give you TDC.I used this because the hole for the locking pin was rusty. A bit of penetrating oil and a gentle tapping located the pin.

Always use in conjunction with number one valve positions. ;):D:D
 
Yep bit of a trouble if you use that mark and it's 180 degrees out if you're removing the pump. "Well dad i took the pump off but can't find the Woodruff key anywhere" :D:D
Or as I did once when I changed the injector pump on the V M , the drive cog has two key ways in it !!!.trial and error to find the correct one.
 
After standing over the garage when they asked me to "witness" them timing it (I had the instructions in my hand) The engine ran OK and the modulation sits mostly at 45-50% sometimes going outside that range. Next project is to change the timing chains as they rattle like a bag of bolts.
Thanks, what about the engine cutting out? Is it cured?
 
Thanks, what about the engine cutting out? Is it cured?
A really weird story developing here. After the last visit to the garage they managed to time the pump so the modulation was acceptable. It didn't cut out. However I drove 60 miles and the car then overheated due to the serpentine belt appearing to slip at times. I put it on a recovery truck and returned it home. I decided to get new timing chains as there was a loud rattle which worried me. To address the belt issue I ordered a new water pump and steering pump (tensioner had been changed previously). On disassembly of the front crankcase cover I found that the FIP sprocket was not aligned! The garage did make a comment when it wasn't running right at first that there was a possibility that they had let the chain slip (i.e sprocket mustn't have been correctly held with the retaining collar when the FIP was being changed). The bright link was one tooth out! How could the garage have eventually timed the pump to show correct modulation with the chain misaligned. I'm now in the process of reassembly with new chains but worried that other damage could have occurred.. Surely the cam sprocket would have been out and could have caused havoc....unless they slackened the camshaft sprocket and adjusted it to prevent valves striking the pistons.
 

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A really weird story developing here. After the last visit to the garage they managed to time the pump so the modulation was acceptable. It didn't cut out. However I drove 60 miles and the car then overheated due to the serpentine belt appearing to slip at times. I put it on a recovery truck and returned it home. I decided to get new timing chains as there was a loud rattle which worried me. To address the belt issue I ordered a new water pump and steering pump (tensioner had been changed previously). On disassembly of the front crankcase cover I found that the FIP sprocket was not aligned! The garage did make a comment when it wasn't running right at first that there was a possibility that they had let the chain slip (i.e sprocket mustn't have been correctly held with the retaining collar when the FIP was being changed). The bright link was one tooth out! How could the garage have eventually timed the pump to show correct modulation with the chain misaligned. I'm now in the process of reassembly with new chains but worried that other damage could have occurred.. Surely the cam sprocket would have been out and could have caused havoc....unless they slackened the camshaft sprocket and adjusted it to prevent valves striking the pistons.
Wammers would know, but I would guess that the cam timing being one tooth would not be catastrophic.
 
A really weird story developing here. After the last visit to the garage they managed to time the pump so the modulation was acceptable. It didn't cut out. However I drove 60 miles and the car then overheated due to the serpentine belt appearing to slip at times. I put it on a recovery truck and returned it home. I decided to get new timing chains as there was a loud rattle which worried me. To address the belt issue I ordered a new water pump and steering pump (tensioner had been changed previously). On disassembly of the front crankcase cover I found that the FIP sprocket was not aligned! The garage did make a comment when it wasn't running right at first that there was a possibility that they had let the chain slip (i.e sprocket mustn't have been correctly held with the retaining collar when the FIP was being changed). The bright link was one tooth out! How could the garage have eventually timed the pump to show correct modulation with the chain misaligned. I'm now in the process of reassembly with new chains but worried that other damage could have occurred.. Surely the cam sprocket would have been out and could have caused havoc....unless they slackened the camshaft sprocket and adjusted it to prevent valves striking the pistons.

@wammers is the one.

Guessing it was the pump out rather than the valve timing though? They could have turned the pump far enough one way or the other to compensate, possibly.

Also, if they've been hamfisted they're more likely to have cracked the idler pulley mount and then the belt will slip sideways and chew itself up.
 
@wammers is the one.

Guessing it was the pump out rather than the valve timing though? They could have turned the pump far enough one way or the other to compensate, possibly.

Also, if they've been hamfisted they're more likely to have cracked the idler pulley mount and then the belt will slip sideways and chew itself up.
Thats what Ive been wondering, the pump shaft is keyed to the sprocket, the sprocket was one tooth out. The flange slots on the pump can only allow a limited movement.

With regard to the overheating issue after the last run, I wonder if a collapsing crankshaft torsional damper would cause slippage of the belt which drives the pumps.
 
Depends entirely on where the other bright link is. And whether the timing pin is located correctly and not stuck on a timing pip.
 
Depends entirely on where the other bright link is. And whether the timing pin is located correctly and not stuck on a timing pip.
With the chain guides so tight to the crank sprocket the chain couldn't have "slipped off" there. I think the only possibility that the chain could have been slack would have been when the injection pump was first changed if the FIP sprocket "dropped". It went from a superb running engine with a leaky FIP to an absolute pig that stopped every couple of miles. I've now changed out the chains and guides myself but without removing the head, so I didn't get inspecting the piston crowns. The additional defect now appears to be the collapsed torsional damper. - I just started the engine to move the car, (only 40 seconds running ) and found the steering jerky. I felt the crank pulley and its very hot! So yet another part now to change. I have ordered a new pulley which is also fitted to the BMW 325 from 1993 (the BMW equivalent is £70 v hundreds for the Landrover part number).
 
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