M70 Rebuild Thread.

[Mikekugel]

Ed, Check this tool out 8^ http://www.brownlinemetalworks.com/d...acklit-display

[Dr. T]

Aren't the rings relatively inexpensive?? So, why not replace them while you have the pistons out and clean out the ring grooves? Love you he pics so far...keep them coming

[IJustDrive]

Scope creep... But you will have a brand new engine! Probably do the same if your in that far.

[dragon850]

Ed, Check this tool out 8^ http://www.brownlinemetalworks.com/d...acklit-display

Ohh YEAH! This is what I was looking for ! Thanks!

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Aren't the rings relatively inexpensive?? So, why not replace them while you have the pistons out and clean out the ring grooves? Love you he pics so far...keep them coming

BMW rings are VERY pricey! There are some alternatives, I believe company Goetze makes aftermarket rings, that are alot cheaper, I cant find a re seller that sells them so far!

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Scope creep... But you will have a brand new engine! Probably do the same if your in that far.

Big time creep! I will get it done, eventually

[cartoonz]

http://shop.advanceautoparts.com/p/g...goe/10727198-P

$20/ per hole

[Fatandre]

http://shop.advanceautoparts.com/p/g...goe/10727198-P

$20/ per hole

For that price I would say its a must to replace.

[Dr. T]

Check with Gault. Realoem shows all 12 for ~$112

[dragon850]

http://shop.advanceautoparts.com/p/g...goe/10727198-P

$20/ per hole

Is this for an M70 application? Pretty cheap!

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For that price I would say its a must to replace.

Agreed.

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Check with Gault. Realoem shows all 12 for ~$112

I could not see that, is there a P#? I am pretty good with real oem, maybe I am blind today

[BMSman]

http://realoem.com/bmw/enUS/showpart...36#11251436986

Price is per cylinder!

[Dr. T]

http://realoem.com/bmw/enUS/showpart...36#11251436986

Price is per cylinder!

Yes of course, I stand corrected!

[dragon850]

Spent about an hour online looking for Goeteze rings specific for M70 for sale in US with no luck. Cheapest BMW rings I found were around $70 per hole, so most likely will stick to my old rings...

[Mikekugel]

Give Sealed Power a jingle, they just might be able to help you.

[dragon850]

Already looked at the online catalog, they do not have an application for M70
There was a guy, Patrick, on the 750 forums who very successfully re ringed his M70 750il. I wonder what rings did he used. I am sure they were not BMW.

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Mahle does not have them, maxsil does not have them, grant does not have them...

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These guys look promising, will give them a ring tomorrow:
http://www.deves.com/faq.php

According to the catalog these guys have the rings for M70 application, my heads are stamped 91. So I am sure the engine is pre 03/1992. That's interesting that BMW used different rings on engine after 03/1992.

[BMSman]

http://www.ebay.com/itm/BMW-750-850-...item4175478d54

Seller in the UK.

[dragon850]

http://www.ebay.com/itm/BMW-750-850-...item4175478d54

Seller in the UK.

Yep, thank you I have seen this. Sold by my countryman (Lithuania) in GBP . However, the price with shipping is getting pretty close to BMW oem rings through ecs tuning.
I will give DEVES a call tomorrow, apparently they have a very good reputation and manufacture the rings from Swedish steel.

[sleepy81]

That part is suicide. First off, these blocks are Alusil, not Nikasil. Run a hone down that hole? > Throw the block away.

Thanks Cartoonz for pointing out my Nikasi mistake. I stand corrected. As for honing, lots of information available on this process from various sources including Sunnen and speciality service providers.
As to the need for ring replacement, the factory end gap limits should be your guide.

[Dr. T]

Thanks Cartoonz for pointing out my Nikasi mistake. I stand corrected. As for honing, lots of information available on this process from various sources including Sunnen and speciality service providers.
As to the need for ring replacement, the factory end gap limits should be your guide.

What are those? Are they published somewhere?

[dragon850]

What are those? Are they published somewhere?

I was looking for any info on this yesterday, no luck.
There is a guru on you tube that cuts apart and examines M70 in detail, when it comes to the rings he was not very impressed. Basically said they are terrible quality. Problem is he explains everything in Russian. So If possible yeah I will replace with something better for my Supercharged setup.

[Fatandre]

Let us know what you will come up with

[whiteghost1]

I used Sealed Power gapless rings on my engine build (regular iron block) and I had to hone the cylinders to a specific surface finish for the rings to seat properly. Not sure if it is relevant in for an Alusil, just my experience.

[cartoonz]

what's wrong with the link I gave you already for Goetze rings?
Deves *might* have a suitable set.
You have to get rings with no chrome in them, just plain iron. Anything else and they'll never seat.

As for all you folks spouting off "Honing is possible, lots of info online, even from Sunnen... etc." You really don't understand that there are not that many automotive machinists qualified to wear the black pointy hat while stirring the cauldron of mystery honing... AND, that process is only to bore/hone/expose to oversize, not to "seat new rings"... i.e., good luck finding a shop that has all the equipment and knowledge to do this process to resize bores.

[dragon850]

what's wrong with the link I gave you already for Goetze rings?
Deves *might* have a suitable set.
You have to get rings with no chrome in them, just plain iron. Anything else and they'll never seat.

As for all you folks spouting off "Honing is possible, lots of info online, even from Sunnen... etc." You really don't understand that there are not that many automotive machinists qualified to wear the black pointy hat while stirring the cauldron of mystery honing... AND, that process is only to bore/hone/expose to oversize, not to "seat new rings"... i.e., good luck finding a shop that has all the equipment and knowledge to do this process to resize bores.

That would be fine, but the link you gave me is not for M70 application. I called the store and they said they do not have m70 application. I will try calling their 1800 number too...

[cartoonz]

Part No. A2050284421GOE = BMW M70 wtf? Says so right on the page!
dimensions are correct too
Oh, they are NOT available from "the store", you HAVE to order them (says that on the page too)

[dragon850]

OK, so I did more research which led me back to Goteze rings. The Deves rings were reported terrible when used on alusil Porsche blocks.
What was confusing me on Advanceautoparts link is a different model number than original Goeteze number : 08-702800-00, however the dimensions are the same 1.75/1.75/3.0 mm
So the worst that could happen is I return them if the P# is wrong after looking at the original box.
I think I got a deal of the century here, all 12 holes for under $200 with a 20% off coupon! (the trick to get extra $50 off is to chat with the representative online because the rings are not coupon eligible item
I measured my rings and they are also 1.75/1.75/3.0 mm :
ATT_1444697352121_DSC_0641.JPG

Part No. A2050284421GOE = BMW M70 wtf? Says so right on the page!
dimensions are correct too
Oh, they are NOT available from "the store", you HAVE to order them (says that on the page too)

[dragon850]

Can experts comment on these 2 connecting rod bolts? According to realoem both can be used.

Shows 2 types available and 1 ended. I would like to use 11247589671 it is alot cheaper. What is the difference ??













Sponsored links

No.	Description	Supp.	Qty	From	Up To	Part Number	Price		Notes
01	Connecting rod		X		04/1990	11241288910	$440.82		ENDED
01	Connecting rod		X	04/1990		11241729487	$209.32
02	CONNECTING ROD BUSH		X			11241278209	$7.06
03	Dowel		24			11241280833	$1.18
04	Connecting rod bolt	L=53MM	24			11241713342	$6.32
04	Connecting rod bolt	L=47MM	X			11241744319	$6.12		ENDED
04	Connecting rod bolt	M9X47MM	X			11247589671	$4.02
05	Bearing shell, blue	45,00MM(0)	X			11241288925	$16.49
05	Bearing shell, blue	44,75MM(+0,25)	X			11241288927	$13.49
05	Bearing shell, blue	44,50MM(+0,50)	X			11241288929	$11.94
05	Bearing shell, blue	44,25MM(+0,75)	X			11241720336	$11.94
06	Bearing shell, red	45,00MM(0)	X			11241288924	$16.49
06	Bearing shell, red	44,75MM(+0,25)	X			11241288926	$13.49
06	Bearing shell, red	44,50MM(+0,50)	X			11241288928	$11.94
06	Bearing shell, red	44,25MM(+0,75)	X			11241720335	$11.94

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This is the connecting rod bearings I am planning to purchase. Looks like they are equivalent to BMW 45mm 11241288925.
Any opinions?
https://www.ecstuning.com/BMW-E31-85...cal/ES2626371/