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Hood seal and fumes/leaks

471 Views 7 Replies 5 Participants Last post by  bigfish95971
Can anyone tell how well the underhood seal is supposed to fit?

My 266k mile ‘96 didn’t have a seal when I bought it. I’m not near my 445k mile ‘96 to check. But I know that I don’t get any fumes on that one.

I just got my hands on a “good used” seal, but it doesn’t quite make the width, see here:

Automotive fuel system Motor vehicle Hood Automotive tire Automotive design

about 1/2” on each side. It definitely helps reduce the fumes in the cabin when stopped with HVAC on.

I do have a manifold issue. The gasket most forward looks replaced/newer than the others, but still “old”, and it is subject to manifold expansion issues.

Furthest forward and most rearward look like this:

Automotive tire Motor vehicle Rim Automotive wheel system Gas

Gesture Finger Tints and shades Wrist Elbow

The center more cylinders show some mismatch too.
Water Automotive tire Tread Wood Tire

I love old diesels but don’t want to be breathing fumes unnecessarily. I have one or two old MB diesels that I’m also experiencing this with, I think from the manifold to turbo gasket. But those cars also have a two piece manifold with a flex tube partway, I suspect to help deal with different rates of expansion.

Any recommendations on where to start? Should I just remove the whole manifold? Should I replace it?

I may do a preeemptive head gasket so prepping now is the best bet.

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There are 2 additional seals on each end of the hood seal I dont see.
You mean the foam pieces that are at both ends? They’re there. Just didn’t make the photo. They are hard, probably worth replacing with … ???
I don't think the hood seal will affect cab ventilation. It seems like it is mainly for making sure airflow is directed below the firewall and not pushing up the back of the hood as well as keeping the elements from creeping in from above. Check your firewall grommet near the steering column and the others. Those would let fumes right in.
Will do. It is markedly improved now that I put that gasket on.
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