engine and drivetrain Oil pump chain replacement suggestions???

[hanch2002]

I just put a rebuilt head, timing chain and guides, and of course a million other parts while I was at it into my 74 2002. I noticed that the oil pump chain has some slack in it. I have had some nice advice on replacement of the chain, etc. (Thanks a million Kurt -- also for the lower timing cover). Anyone else out there replaced an oil pump chain with the motor in the car? This looks pretty difficult to me. Also if I replace the oil pump chain itself will it be about the right tension? Would I need to put a shim in? Or is that a you will find out when you get to that point situation? The oil pump itself seems to be working well (when I unscientifically viewed the amount of oil being pumped out of the oil distribution tube). Any advice would be helpful. I do not have an engine hoist or lift at my disposal. Also if I don't replace the chain now... I plan on maybe driving the car another 10K -- 12K before doing a complete rebuild would it be problematic? My guess is no as long as the chain doesn't somehow fail and beak. If I elect to have someone do this part of the job for me any recommendations for a mechanic in the Albany, NY area? Thanks to all.

[TobyB]

How much does the chain flop?

1/4" isn't abnormal in an older engine.

And often it's sprocket wear as much as chain wear.

you could also just re- shim what you have.

But you're right, with the engine in, it's going to be a pain,

and a lot of work to clean everything really well...

t

[jgerock]

Pulling the bottom end of the engine while in the car is a royal pain. I changed my oil pump, rod bearings, piston rings and head gasket while the engine was still in. I won't do that again.

BMW makes the oil pump shims in (2 I think) different thicknesses. This has been discussed here many times, but the general idea is to get the oil pump chain almost tight that there is barely any deflection when pushed in with your finger. Mine was pretty slack, so I replaced the pump (Febi brand), drive gear and shimmed the chain. It is a tricky job to get the pump, shims and drive gear aligned.

I used a very dense piece of 4x4 wood and heavy chain to support the engine from the fenderwells.

Looks are deceiving! The pan would NOT go any farther back due to the pump pickup and crossmember, so I had to remove the back portion of the pump, push the pan rearward, reinstall the pickup, then bolt up the pan.

Oil pump removed

[c.d.iesel]

what ever you don't do now - you will not do later-

it's the nature of the species.

the crank needs to be in the correct position,

rear journals swung up out of the way for the oil pan to come forword and out easily. the motor needs to be jacked up, and or supported from

above. Remove the distributor cap and rotor. Disconnect the battery.

Buy 2 of each thickness shim, and NEW SEALING O-RINGS FOR THE PUMP!. All that effort is for -0- if you reuse the old o-rings.

[john_a]

This thread contains a few depictions of how to do related work (replace pump / gear / shim) but nothing yet on the actual subject "chain replacement "

The other stuff mentioned can be done (with extra difficulty) in the car, but to swap the chain itself you need to get the timing chain out of the way. That adds a whole 'nother level of complexity and personally I would address the pump chain when the engine is OUT.

Do you really want to contort around the subframe & oil pan, AND have to remove the timing chain with the engine in, just to get that pump chain off? If you are already planning a rebuild in the near future, leave it till then, or move up your schedule to do it now.

[allbim]

This thread contains a few depictions of how to do related work (replace pump / gear / shim) but nothing yet on the actual subject "chain replacement "

The other stuff mentioned can be done (with extra difficulty) in the car, but to swap the chain itself you need to get the timing chain out of the way. That adds a whole 'nother level of complexity and personally I would address the pump chain when the engine is OUT.

Do you really want to contort around the subframe & oil pan, AND have to remove the timing chain with the engine in, just to get that pump chain off? If you are already planning a rebuild in the near future, leave it till then, or move up your schedule to do it now.

I recently purchased an oil pump chain with a removable link, sorry I can't remember who from.

[john_a]

I recently purchased an oil pump chain with a removable link, sorry I can't remember who from.

I've seen removable master links on timing chains in the aftermarket, as well as for the pump chains.. but I've never been tempted to risk using either. It's not surprising they're available, because these are standard chain sizes manufactured universally (I think the pump is 3/8 x 5/32" and the timing chain is 3/8 x 7/32") so it's no great challenge for a chain company to produce them for our cars. I used to like the old IWIS chains, but the service parts they sell now have a different roller (supposedly quieter) and I have bought nice M10 timing chains made by IZUMI of Japan.

Since having a master link won't change taking job of taking an original chain off, there's not any real savings most of the time. Only if the previous rebuilder used one with a removable master link, could you then replace it with the same type and save a few steps if it was necessary.

[allbim]

I recently purchased an oil pump chain with a removable link, sorry I can't remember who from.

I've seen removable master links on timing chains in the aftermarket, as well as for the pump chains.. but I've never been tempted to risk using either. It's not surprising they're available, because these are standard chain sizes manufactured universally (I think the pump is 3/8 x 5/32" and the timing chain is 3/8 x 7/32") so it's no great challenge for a chain company to produce them for our cars. I used to like the old IWIS chains, but the service parts they sell now have a different roller (supposedly quieter) and I have bought nice M10 timing chains made by IZUMI of Japan.

Since having a master link won't change taking job of taking an original chain off, there's not any real savings most of the time. Only if the previous rebuilder used one with a removable master link, could you then replace it with the same type and save a few steps if it was necessary.

Using a chain with a removable link will eliminate the need to remove the timing chain. That would save a lot of work. As far as reliability goes, I can only tell you that it takes a lot of force to remove the clip that retains the master link.

[john_a]

Using a chain with a removable link will eliminate the need to remove the timing chain.

Not the first time, it won't.

Removing the original (conventional) chain would still necessitate removing the timing chain.

Subsequent replacements with another removable master link chain would be the only time you save steps.

I'd guess that on the majority of pump chain replacements, you won't find a master link in place on the old chain, so you'd most likely be taking off the timing chain no matter what kind of new chain you are installing.

[allbim]

Using a chain with a removable link will eliminate the need to remove the timing chain.

Not the first time, it won't.

Removing the original (conventional) chain would still necessitate removing the timing chain.

Subsequent replacements with another removable master link chain would be the only time you save steps.

I'd guess that on the majority of pump chain replacements, you won't find a master link in place on the old chain, so you'd most likely be taking off the timing chain no matter what kind of new chain you are installing.

You've got a point there. It is possible to break the chain though. There used to be a tool available to break motorcycle chains.

Personally, I would pull the engine.

[hanch2002]

Thanks to everyone! I'm pretty new at this and I'm amazed at how helpful and knowledgeable, not to mention fanatical, "real" 2002 owners are! After measuring the chain slack (a little under 3/16" and a very close inspection), I've decided to leave it alone for now. I did get the new timing chain, rails and the rest of the engine back together and it is running like new! I won't be driving the car a lot and I'm planning on doing the body work soon. Next year or year after if I still have the interest and stamina I'll probably get a hoist and engine stand and pull it to rebuild the bottom end -- then I'll put in the new gears and chain (possibly a new oil pump). Thanks again to all!

[Djthom]

Does anyone know what brand/part number is correct for removable link oil pump chain, including being the correct width?   When I rebuilt my engine I ordered a new chain but the incorrect S14 one was sent.  The original chain seemed ok so I reused and now I have an oil pressure issue I need to resolve and want to do the chain while I'm in there.  

[TobyB]

I haven't seen the Iwiss 'master link' chain since before this thread was created.

 

As you note, just finding the right one these days has gotten to be a real pain.

 

t

 

[Schnellvintage]

I believe you can buy the oil pump chain separately, from IE.  You will need to re-shim your oil pump correctly.

Sorry, they do not have the master link.

 

Oil Pump Sprocket & Chain – M10 – Ireland Engineering | Racing & Performance Parts for BMW & MINI (iemotorsport.com)

[Djthom]

Found on eBay Oil Pump Chain N969RK for 2002 1602 2002tii 318i 320i 1976 1967 1968 1969 1970.  Is this going to work or is this a shot in the dark?

 

https://www.ebay.com/itm/Oil-Pump-Chain-N969RK-for-2002-1602-2002tii-318i-320i-1976-1967-1968-1969-1970/183806267986