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mad-dan

diesel injector pump removal

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does anyone know where i could find a guide on how to remove the diesel pump, or can anyone give me a quick guide..

I've removed the inlet manifold, undone all the pipes, unbolted the pump from the engine (2 nuts at the drive end, one nut holding the support bracket) unplugged the multi plug, removed the selonoid wire, so really i'm stuck with removing it, do i have to remove the cam chain? if not, how do i withdraw it from it's location?

any help would be great

Thanks

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There is a special tool to remove pump which also holds the timing gear in place on m51 engines.You do not need to remove belt tensioner,you unscrew the end cap and then reach inside and remove bolt or nut from pump shaft (cannot remember if it bolt or nut).Then the tool which is a tube with an internal thread goes into the tensioner housing and screws onto the pump sprocket,this holds it into place when pump is removed and stops the gear falling into bottom of timing case (if it does then to remove timing case the head has to come off).Once this is in then a bolt on front of tool is tightened and this pushes pump shaft out.I have removed a pump using one of these tools and it only takes a few minutes to get pump out,you must pin the crankshaft with a locking tool and there is a plate to lock the camshaft into place.The hardest part for me was locking the crank with the rod as it was very tight fit.Also when you time the pump you should use a dial gauge although I sufficed with a vernier,and you need to turn the pump in only one direction when setting timing on it so as not to leave slack in timing chain which will cause rattle and affect timing setting.People have got away without using the removal tool but I think that is more to luck than anything else.If the key on pump shaft is loose fit then a dab of loctite will hold it in place and stop it coming out and falling into timing case.Do a google search for m51 pump tool and you will have more idea of how it works once you see the tool.

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The tool is helpful, but if you have an assistant you can do it without - but entirely at your own risk for the reasons Doug outlines. You needed to make some marks on the pump body against the block really, but you might have some witness marks on the pump so you can fit the replacement pump in the same position - it won't be 100% but is a starting point.

What you can do is slacken the nut on the pump shaft (don't remove it) and give it a smack to loosen the pump. You need to grovel in the engine bay and hold the gear in place, undo the nut and get your willing assistant to lift the old pump out and lower the new one in. It's tricky on an E36 (what we did it on) and harder still on an E34 with the front opening bonnet. As for timing, we refitted the pump in the same position as the old one. Ours had a poor idle, so I slackened the two 13mm nuts and using a hammer and screwdriver, nudged the pump around until the idle was okay. It also drove fine and didn't smoke - were we just lucky? :-)

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Lucky ish,same as me,although I used a vernier to try and time the pump and it really required four hands to do it instead of my two I got mine to run nice although its a bit borderline when on veg oil mixed with diesel as it pinks/detonates more than it really should when engines cold/part worn.If you get timing to far out the engine warning light will come on at certain rpms,all this means is the ecu has run out of scope in its inbuilt timing maps simply because the pumps base timing setting is out.This never happened to mine but I picked that bit of info up on another site a week or so ago when someone had fitted a pump and had light come on and loss of power just of tickover.That is the one trouble with this ecu operated system,the timing has to be near spot on,if you move it so far you can get away with it a bit,after that the ecu compensates what you have done and reverts it back to where it wants it to be

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If I only want to remove the pump to fit on another E34, so from a car for parts, meaning dropping bits into the cam case dont matter, can i simply unscrew the nut on the end of the spindle once all other bolts and fuel lines connections are off and remove it?

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Make sure you have the right pump as there are three different ones and they don't interchange. 995 on cars up to Feb 94, 993 up to Jan 1995 and the 994 for cars with EWS from Jan 1995 including the E39 525tds. The last one might be coded to the ECU with the chipped key, can't remember now. 

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