Oil Pump problem
Turbo Mini Forums

Hi guys,

Just fitted my new oil pump from mini spares (GLP110MS). It fits fine but when we fitted the cam there was a lot of movement n the cam.

After removing the pump and comparing it to the old one we discovered that the shaft that comes out of the oil pump that locates in the cam shaft is shorter on the new pump than on the original one, therefore allowing the cam to slide backwards and forwards a bit.

Is this normal or have i got a dodgy pump?

Cheers,

Guennie

100% BMW Free

I brought a mini spares hi capacity turbo oil pump and found it to be rubbish. As far as I can remember the tolerences where all over the place on the rotors. I ended up scrapping this one and brought a powerflow turbo pump which was top quality. It's funny really as minispares stuff is usually great (I find). :)

i did do a search on here before posting and read something about the tolerences. looks like i'm going to be taking a trip to avonbar tomorrow then!

cheers for the quick reply.

100% BMW Free

did you fit the camsprocket? it is the cam sprocket and triangle plate that set the cam endfloat, not the pump, the peg on the pump has nothing to do with that

I thought the minspares one was also a powerflow item nowadays...same as the Avonbar one?

It sounds as you've got a small bore oil pump.

thanks for the replies so far. I've just taken a pictue to make it clearer what i mean,



The pump on the left is the new one and on the right is the original one. you can see the shaft on the new one is about 2mm shorter than the other. this is the same size as the movement i'm getting with the cam. Is this the reason why the cam is sliding or is it just a coincidence?

100% BMW Free

As above, the high capacity one I got from MiniSpares was a Powerflow (apparantly they have been for a while now), AND, the end float on the cam has NOTHING to do with the pump shaft - do as miniminor63 says then check endfloat.

If the end of the drive flat is touching the bottom of the slot in the cam (rather than just driving on the sides) when the cam is fitted properly, I would be very worried as the cam wouldn't be able to expand.

Edited by Rod S on 11th May, 2009.

Schrödinger's cat - so which one am I ???

in that case the end float is massive at the moment! about 2mm. is this shimable?

also is it possible to shim it from the oil pump side? it seems like it would sit in the bearings better than way.

Edited by Guennie on 11th May, 2009.

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Dude, fit the triangular plate, then fit the timing gear with the nut, tighten the nut up and then check the end float

we did that last night and torqued up the nut to 30lb-ft and the whole assebly, cam and timing gear, has a lot of movement (end float), it just seems like i'd be packing it out rather than shimming! about 2mm but i'll take an accurate measurement this evening. Is this a normal end float or do i have an issue?

the cam is a reprofiled phase 2 turbo cam and the cam bearings in the block have just been replaced.

100% BMW Free

Something very wrong then - the way the end float works is the "back" of the sprocket has a raised boss. This raised boss goes through the hole in the triangular plate and butts up against the flat face on the end of the camshaft.

Thus the back of the sprocket and the end face of the cam run either side of the triangular plate.

The raised boss is 3thou taller than the plate is thick so you get the 3thou endfloat required.

If the end float is slightly more, it's usually a worn trianguler plate (it has whitemetal bearing material on one side).

If the end float is severe, it usually means the sprocket boss isn't going fully home to sit on the end of the cam - sometimes the key rocks a bit in its slot and causes it to stick.

Take the cam out and just put the sprocket on the end and make sure the two meet, then slip one corner of the triangular plate into the space and see how it looks.....

Schrödinger's cat - so which one am I ???

Thankyou very much mr Rod S :) . That all makes a lot more sense in my head now! I'll take a closer look when i get home and let you know how it goes.

I'm trying to get it on the road for sunday, but i don't want to cut any corners!

Just read the details on the "camshaft triangle plate" on minispares. That explains how if worn the cam can literally "walk back and forth". This sounds very much like the problem i'm having.

thanks once again guys

Edited by Guennie on 11th May, 2009.

100% BMW Free

No problem.....

Just one point - my "test" of putting the sprocket on the end of the cam (with it out of the engine) and slipping a corner of the plate inbetween is only valid for checking the sprocket is going fully home..... it doesn't check for wear on the plate causing your problem because they only wear in the centre, not on the corners.

Schrödinger's cat - so which one am I ???

ok thanks.

Just to claify then;

the length of the shaft on the oil pump has no effect on the end float of the cam shaft, as long as it slots into the cam it will work and pump oil.

Is that right?

100% BMW Free

Yes,

If you are worried about how much the flat on the end of the oil pump drive is entering the slot on the end of the cam, first sort out your cam end float....... Then deliberately turn the end of the pump shaft 90 degrees out relative to the slot and try to push it home (which obviously it won't go) and see how far away from the block the oil pump is.

A bit tricky to see as its in a recess but that gap is how far the drive flat goes in when it's lined up right.

Schrödinger's cat - so which one am I ???

cool, im not too worried about the oil pump drive going into the cam, it seems to fit fine. i'll go and get a new triangle plate asap. From memory the old one did look a little worn!

Thanks once again for your help :)

100% BMW Free

Final point then - be aware the traingle plate only goes one way around (to get the whitemetal face the right side) and in one position (because of a drain hole).

To achieve this, the three bolt holes are NOT on an equal triangle, so of the 6 possibilities it should only fit in one....

But, the unequal triangle is very close to being equal and I've seen the plates with bolt holes enlarged to make it fit in the wrong place - often the cause of wear.....

Schrödinger's cat - so which one am I ???

A good reason NOT to fit the oil pump before the timing gears is done.

Very good point Vegard....

Guennie, by way of an explanation, if you try to fit the cam sprocket with the oil pump already bolted in place and the sprocket is a tight fit so it needs "tapping" into place...... You are actually hammering against the oil pump shaft which means you are hammering against the outer cover plate of the pump.

Some of the cheap pumps have an alloy outer plate which easily cracks (esp. around the bolt holes).

Even with the steel outer cover plates, it is still a really bad idea.

Also you won't actually get the sprocket in place because the camshaft will be too far away from it resting on the oil pump shaft.

This is another good reason for making sure the sprocket is a proper fit on the end of the cam before installing it.

Schrödinger's cat - so which one am I ???

Cheers guys. You've been a great help! There are obviously a lot of very experienced and knowledgable people on this forum! Thanks for all of the tips and advice you've given me so far, i'm sure it won't be the last time i'm looking for help!!!

Guennie

100% BMW Free