I replaced the exhaust manifold gaskets today on my '90 300SE. Unfortunately, I now have an exhaust leak. I think it's the forward down pipe. I thought I had it matched up well before tightening it up.

I loosened it and tried again, still leaking. I tried using soapy water to see if I could find where it's leaking, no luck.

I did notice some wear on the manifold at #4 cylinder, I cleaned it up and it was very minor.

Any suggestions as to what to do?

__________________
Mr. BILL

91 300E 120K
90 300SE 275K (sold)
92 BMW 525iM 120K
90 BMW 525iA 175K
85 300D 175K (sold)
84 300SD 245K (sold)

Well, I must say, I'm deeply hurt (not) that no one answered my question. Your punishment, a follow up post.

I gave up and called a specialty muffler shop the dealer recommended. They found the forward down pipe was cracked near the manifold. They used a very high tech precision instrument to locate the leak...a rubber hose.

Anyway, they fixed (welded) the crack and I'm purring smooth and quiet. The reason for the follow up is, I'm not sure it's necessary to take the exhaust pipe loose to remove the manifold. At least not on a '90 300SE.

This might save someone searching the subject a little time and money.

__________________
Mr. BILL

91 300E 120K
90 300SE 275K (sold)
92 BMW 525iM 120K
90 BMW 525iA 175K
85 300D 175K (sold)
84 300SD 245K (sold)