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Exhaust manifold

Posted: Mon Nov 09, 2020 5:29 am
by jsspagg
I have a 1980 Euro 635 M90 engine. It's been 10 years since it was last on the road and I am going through pretty much everything in order to get it back on the road. I have been using realoem.com to get the part numbers for replacements. There have been a few discrepancies that I have been trying to work through. Maybe someone here can provide some insight. I'll start with two current issues:

1) realoem.com tells me the output shaft bellows repair kit is part number 33219067913. I ordered this part number from my local BMW dealer in August. Recently they told me it's not available. Looking at another site- FPC Euro, they do not have this part number but suggests part number 33219067912. Is there is a difference?

2) The exhaust manifolds that I removed have the part number 1250603 clearly stamped on them- both front and back. I cannot seem to source this part number. Realoem.com lists the part as 1250601. 1250601 part is available and as best I can tell, appear to be the same as what I currently have, but afraid to make the purchase at over $300 each. Anyone know if there is a difference?

Also, anyone know if the the gasket (#4) with the heat shield (for the plug wires) has the same fitment as the standard gasket (#3) ?


Thanks for any insight.

Re: Exhaust manifold

Posted: Tue Nov 10, 2020 9:24 pm
by Pasocb
jsspegg,

The exhaust manifolds from my 07/1980 build date Euro 635 are pictured below.
Front and back are slightly different: 1 274 808 HD 1 and 1 274 808 HD 2.
In my last engine build, I used the larger gaskets with the integral heat shields without issue.

Re: Exhaust manifold

Posted: Wed Nov 11, 2020 1:34 am
by Ralph in Socal
OP - I suggest you do a lot of research to determine what manifolds you have

M90 factory exhaust manifolds are not the same as M30 manifolds. And the M90 manifolds are probably NLA at the dealer. Good luck

Ralph

Re: Exhaust manifold

Posted: Sat Nov 21, 2020 4:39 am
by jsspagg
I was able to do a repair on the manifold so at least for now, I wont need a replacement.

I sourced a gasket with the heat shield so I will install that when the time comes.

In the meantime, any input from anyone on the output shaft bellows?

Re: Exhaust manifold

Posted: Sun Nov 22, 2020 12:00 am
by bpoliakoff
I have a good one

Re: Exhaust manifold

Posted: Sun Nov 22, 2020 6:41 pm
by Ralph in Socal
On the output shaft repair kits, look at the new ones carefully

At the metal flange that the bellows attaches to, the early e12 (Series 1) flange is flat and uses halfmoon washer strips

The flange for later style (Series 2) has raised areas so you have to use the later style washer strip That has 2 holes bridged by a metal strip

You will not be able to use the halfmoon washer strips on the new style flanges

Ralph

Re: Exhaust manifold

Posted: Sun Nov 22, 2020 8:34 pm
by bpoliakoff
Hey Ralph, when I rebuilt mine, I just ordered a set of rebuild kits from some internet parts provider. i can't remember if they were model year specific, but they worked fine with the 1/2 "moons"

Re: Exhaust manifold

Posted: Sun Nov 22, 2020 10:05 pm
by Ralph in Socal
Just providing the OP with some insight into a possible problem.

I’m lucky to have plenty of the later washers but others may have to buy 12 of them

Ralph