Dear mother of God. Top of intake manifold not flat. (1 Viewer)

[Beehanger]

Gentlemen,
I’m noticing post engine rebuild and reinstall I’ve got myself in a big pickle right when I thought I was at the finish line.
! I’m beyond my scope on knowing how to protect fix this one and seems like I have one shot at it. The Intake manifolds carb surface isn’t flat. I took a wire wheel to it a few months ago (lightly) but after mounting am noticing the scratch marks and slight dipping thats either from the wheel or warpage. Took a straight edge to it isn’t flat and dips in the middle on the sides. it. I have a cruiser guy telling me this is an issue with cruisers and to get A new intake or RTV it (yikes) but no one has seen it in person. the most wobble on the very edge where I recall knicked it when trying to get old gasket off.

I wanted to double check before I did anything. It’s hard with something so consequential to go with forum advice. Was going to file it with either a fine file or 400 grit sandpaper on a sanding block and bring the entire surface down 1-2 millimeters or So. This is a tricky one for sure….

See videos and photos for reference in regard to how much of a gap there is and the scratches on surface.
video link : cruiserdan - https://www.dropbox.com/scl/fo/z5a7tfoof5d6gxu5jfjyd/h?rlkey=z0got4pxx2hgsqpjn75rm6ei3&dl=0

Best
Dan

 

[OSS]

Yeah if you got a ‘steel’ sanding block that’s perfectly flat and big enough, it’s possible to level out the high spots on the manifold. But sanding aluminum by hand will be tedious.
I’d use wet/dry emory paper and wet sand it with WD-40 (sanding wet oil) if I ended up having to do it this way. The sandpaper will last much longer when wet sanding.

 

[bj70bc]

.

 

[Rgill]

Gentlemen,
I’m noticing post engine rebuild and reinstall I’ve got myself in a big pickle right when I thought I was at the finish line.
! I’m beyond my scope on knowing how to protect fix this one and seems like I have one shot at it. The Intake manifolds carb surface isn’t flat. I took a wire wheel to it a few months ago (lightly) but after mounting am noticing the scratch marks and slight dipping thats either from the wheel or warpage. Took a straight edge to it isn’t flat and dips in the middle on the sides. it. I have a cruiser guy telling me this is an issue with cruisers and to get A new intake or RTV it (yikes) but no one has seen it in person. the most wobble on the very edge where I recall knicked it when trying to get old gasket off.

I wanted to double check before I did anything. It’s hard with something so consequential to go with forum advice. Was going to file it with either a fine file or 400 grit sandpaper on a sanding block and bring the entire surface down 1-2 millimeters or So. This is a tricky one for sure….

See videos and photos for reference in regard to how much of a gap there is and the scratches on surface.
video link : cruiserdan - https://www.dropbox.com/scl/fo/z5a7tfoof5d6gxu5jfjyd/h?rlkey=z0got4pxx2hgsqpjn75rm6ei3&dl=0

Best
Dan

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I was able to use a good file and get mine flat. I used machinist blue and sprayed the mounting surface. First couple of passes remove the marking dye showing the high spots. continued to file until all the blue marking dye was gone. Did not take much to get flat surface. I used the same technique on the thermostat housing.

 

[cps432]

Yeah if you got a ‘steel’ sanding block that’s perfectly flat and big enough, it’s possible to level out the high spots on the manifold. But sanding aluminum by hand will be tedious.
I’d use wet/dry emory paper and wet sand it with WD-40 (sanding wet oil) if I ended up having to do it this way. The sandpaper will last much longer when wet sanding.

Aluminum is softer than oak. It can go into a table saw no problem. It is not tedious to sand it by hand. It’s less tedious than sanding oak end grain. Because it’s so soft it’s best to sand it dry. Don’t breath the dust though. Whatever you do don’t do that.

 

[toy_tek]

I think you’re on the right track.

I’d remove the two studs, stuff a rag in there, then get a small cutoff chunk of flat granite from a local countertop shop and sand it flat. Keep your vacuum at the ready. Clean it thoroughly when done.

An *extremely* thin layer of RTV could be used, but if it’s flat enough after sanding, this shouldn’t be needed.

 

[Beehanger]

I think you’re on the right track.

I’d remove the two studs, stuff a rag in there, then get a small cutoff chunk of flat granite from a local countertop shop and sand it flat. Keep your vacuum at the ready. Clean it thoroughly when done.

An *extremely* thin layer of RTV could be used, but if it’s flat enough after sanding, this shouldn’t be needed.

What grit sandpaper?