Intake Manifold alignment

[Pat O']

I'm working on cleaning up miscellaneous details on my car. I had noticed that there were little puddles of oil around some of the intake manifold bolt and evidence of anti freeze seeping also. I pulled the intake tonight and noticed that some of the bolts were pretty oily. I also noticed a pretty fair amount of oil seepage around the lower half of the intake manifold gaskets. The amount of black silicone on the front and rear of the intake was also pretty impressive. Since I've been scouring these boards for tidbits, I knew what to expect. The motor is a 340.

I cleaned up the mating surfaces and settled the intake back into place and took the attached pictures. One shows the bolt hole misalignment and the other shows the gap at the front of the manifold-engine block. I hope the pictures are sized correctly to show the situation.

Using a feeler gauge I come up with a 0.079-0.080 inch gap between the top of the block and the bottom of the manifold.

My questions is, is that measurement sufficient to to take the manifold to a machinist and have it milled correctly for a better fit?

Thanx for any advice.

[Pat O']

I'll try a larger picture, still new at this.

[cudabob496]

I would place the intake on the heads, without the gaskets, and feeler gauge all the way around, to make
sure there are no huge gaps.  If heads or intake were ever machined, that could cause this problem. The block
being decked (milled) can also contribute to the problem. If there are significant gaps, you can sometimes use two gaskets to make up the difference. Did that on
my big block.  Also make sure all the intake bolts screw in freely and are centered in the intake bolt holes.
Making the intake bolt holes a little larger is also sometimes required, if intake or head surfaces were machined.
This is my experience with a 440.

If gaps are good, may just need a better gasket, or the bolts weren't torqued properly.

If you mill one surface, that can mess things up even more. That's why I suggest double gaskets.

A bad seal between intake and heads can also cause excessive oil consumption.

[Chryco Psycho]

oil will always seep up the bolt threads , as long as the sides of the intake are parallel the intake should seal fine , you have to recheck the bolt torque too as the gasket will compress & the bolts will end up lose , generally this is the first thing I check when tuning an engine