I have one question for you guys. I'm in the process of doing a complete overhaul of my engine and tonight (while waiting for Milton to get here) I took apart the oil pump. Even though I bought all the internals for basically rebuilding it I found out that at some point in time some metal pieces made it into the pump. Both rotating parts have gouges and pieces of metal embedded into them which doesn't worry me much since I got them new. The housing is a different story though. There are deep gouges in it and I'm not sure if it's usable as it is. I understand that oil pumps are NLA but can the housing be purchased? If not, does someone have a spare one that is willing to part ways with? Here are some of pictures of the housing and other components:
https://i.imgur.com/AI8VW1i.jpeg
https://i.imgur.com/9FBUdCP.jpeg
https://i.imgur.com/kLsotiZ.jpeg
M30 oil pump housing with damage
Re: M30 oil pump housing with damage
My experience with this sort of pump is with hydraulic systems but gerotor pumps are gerotor pumps. Excessive clearance on the side of the rotor will allow fluid to "slip by" and give less flow and pressure. Really sort of depends on how deep the grooves are whether its a problem or not. make sure you measure the diameter of the bore, and the other face for wear. Excessive clearance there will cause you problems too.
What you might be able to do here if you know someone with machining capabilities is to have the inside bottom faced off back to flat and smooth. Remove the same amount of material from the top of the pump housing. That would restore the internal clearances between housing and rotor and give you a proper surface to work with. Probably wouldn't take very much to clean it up either. Just need someone with a lathe that has enough swing to put the whole housing in.
What you might be able to do here if you know someone with machining capabilities is to have the inside bottom faced off back to flat and smooth. Remove the same amount of material from the top of the pump housing. That would restore the internal clearances between housing and rotor and give you a proper surface to work with. Probably wouldn't take very much to clean it up either. Just need someone with a lathe that has enough swing to put the whole housing in.
-
Chimi-Changa
- Posts: 1648
- Joined: Nov 08, 2011 11:02 PM
- Location: West Bro, MA
Re: M30 oil pump housing with damage
Hi Jim,
Not sure if these are still being made but they look amazing, I think they are on instagram also:
https://ns.mye28.com/viewtopic.php?t=160675
There are two housings that I have seen, and have heard some use two shims also.
Not sure if these are still being made but they look amazing, I think they are on instagram also:
https://ns.mye28.com/viewtopic.php?t=160675
There are two housings that I have seen, and have heard some use two shims also.
Re: M30 oil pump housing with damage
Looked at the link in Ebay and there's nothing there. I did find someone selling a lot of M30 oil pump parts and the housings looked much better than mine so I bought it. I've been trying to remove the dip stick funnel but haven't been able to. Need to remove it to gain access to the other valve for cleaning.Chimi-Changa wrote: Oct 09, 2024 9:21 AM Hi Jim,
Not sure if these are still being made but they look amazing, I think they are on instagram also:
https://ns.mye28.com/viewtopic.php?t=160675
There are two housings that I have seen, and have heard some use two shims also.
Re: M30 oil pump housing with damage
A good CNC-/machinist should be able to mill the face back a bit, and then mill the housing itself a bit for the correct height. If you can't purchase the plates, just get a new one laser cut for you.jimoreno wrote: Oct 08, 2024 9:12 PM I have one question for you guys. I'm in the process of doing a complete overhaul of my engine and tonight (while waiting for Milton to get here) I took apart the oil pump. Even though I bought all the internals for basically rebuilding it I found out that at some point in time some metal pieces made it into the pump. Both rotating parts have gouges and pieces of metal embedded into them which doesn't worry me much since I got them new. The housing is a different story though. There are deep gouges in it and I'm not sure if it's usable as it is. I understand that oil pumps are NLA but can the housing be purchased? If not, does someone have a spare one that is willing to part ways with? Here are some of pictures of the housing and other components:
https://i.imgur.com/AI8VW1i.jpeg
https://i.imgur.com/9FBUdCP.jpeg
https://i.imgur.com/kLsotiZ.jpeg
Re: M30 oil pump housing with damage
personally I don't think thats a CNC job, would take longer to program than makes any sense. Its a simple enough job on a manual machine though. I'd do it on a lathe but it could be done on a mill too.
Thats kind of the trick with this sort of work, there are multiple ways to fix it using different machines, but ultimately they end up at the same destination and all of them will work.
Thats kind of the trick with this sort of work, there are multiple ways to fix it using different machines, but ultimately they end up at the same destination and all of them will work.
Re: M30 oil pump housing with damage - need your help!
Last update: So I got a collection of M30 oil pump parts that someone was selling on Ebay. I got 2 housings, two pump "guts" and two rear housings among other things like a new chain still in the box, a couple of gears and valves, springs.
In the picture are the housings in the following order right to left: my housing with the deep gouges, the middle housing with no gouges on the front "face" but some roughness on the inside wall and the one on the left has no roughness on the inside wall but some scratches on the front "face" (not as bad or deep as mine).
Which one would you use?
https://i.imgur.com/xbzZs22.jpeg
By the way, there's one back housing piece that looks like it was never installed but I guess it's for the older version of the pump with no over pressure valve? (the bigger one) If anyone is interested in it let me know and I can send pictures.
In the picture are the housings in the following order right to left: my housing with the deep gouges, the middle housing with no gouges on the front "face" but some roughness on the inside wall and the one on the left has no roughness on the inside wall but some scratches on the front "face" (not as bad or deep as mine).
Which one would you use?
https://i.imgur.com/xbzZs22.jpeg
By the way, there's one back housing piece that looks like it was never installed but I guess it's for the older version of the pump with no over pressure valve? (the bigger one) If anyone is interested in it let me know and I can send pictures.
Re: M30 oil pump housing with damage
I'd go with the housing with the cleanest faces as a gouge there will directly connect the input to the output so to speak. Gouges around the outside of the housing really shouldn't have much of an affect on pumping as the clean parts of it will still "seal"
There are specs for rotor clearance to housings so it is worth checking those if you can find them, especially if you are mixing and matching parts together.
If you want an improvement in idle oil pressure you can also fit the oil pump drive gear off of an M30B35 (part# 11411707147), it has fewer teeth and therefore spins faster. The later oil pump has a simple tensioner that our B34 don't have so you need to run some extra shims between the pump and block to tension the chain. Those used to be available in thicker sizes from BMW but now only the thinnest are available, I made my own roughly 0.8 mm thick using some thin sheet metal and it was not hard with basic fabrication skills. You need to use a 44 link chain with this sprocket, part# 11411707163
There are specs for rotor clearance to housings so it is worth checking those if you can find them, especially if you are mixing and matching parts together.
If you want an improvement in idle oil pressure you can also fit the oil pump drive gear off of an M30B35 (part# 11411707147), it has fewer teeth and therefore spins faster. The later oil pump has a simple tensioner that our B34 don't have so you need to run some extra shims between the pump and block to tension the chain. Those used to be available in thicker sizes from BMW but now only the thinnest are available, I made my own roughly 0.8 mm thick using some thin sheet metal and it was not hard with basic fabrication skills. You need to use a 44 link chain with this sprocket, part# 11411707163
Re: M30 oil pump housing with damage
Thanks. What I'm going to do is get 3,000 grit sandpaper and see if that smoothes out the wall area. If not it's going in anyway. I did find more evidence of metal particles in the big over pressure valve as there were nasty gouges on that one also. Probably why the oil pressure light took a little bit longer to go off when starting the engine. The oil pump parts I got from Ebay had a very nice (looked like new) valve. Getting ready to assemble the pump tonight hopefully.