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I experienced an oil leak from the intake manifold front seal so I took the time to pull it back off and re-do it right.
For those who are unaware, most engine builders will recommend that you do not use the cork gaskets for the front and rear seals. Instead, "glue" new gaskets for the sides (between the manifold and the heads) using grey RTV on the coolant passages. Then put a 1/4" bead of RTV grey on the front and rear seals. Let it harden slightly (one hour) then "stack" a second smaller bead on top of it. Place the manifold on and torque down immediately.
The last time I did this I had a strong helper and although we were careful as we could be, the heavy manifold still dug into the front bead of fresh RTV, and therefore it started to leak oil soon afterwards.
This time I rigged up a bracket out of wood and threaded rods to make the installation nearly fool proof. The long member is a 2x4 pine ripped in half. The short pieces are 1/2" x 1-1/4 oak. All are scrap from other projects. I bevel-cut the long member to accept the short ones so they are more-or less at the same angle as the carb plate. The oak gets pre-drilled holes and fastened to the pine with deck screws.
This rig isn't strong enough to break the old gasket seal- I use an axe handle in the front thermostat housing to do that. Then I used my bracket to raise the manifold off the engine, about 1/2" off the front seal and 2" or so off the rear seal by simply turning the four nuts in sequence.
Along with a helper this allowed me to use the "handles" to pick up the manifold, move it back 3/4" to clear the small bypass hose, then lift it out and onto my workbench.
I measured the heights of the nuts on the threaded rods to set the bracket in the same position for the placement, then removed it to allow cleaning the underside. Then I remounted the bracket and used it as a handle to carefully maneuver the bypass onto the short hose, with little chance to smear the fresh RTV. Once I got the manifold hung above it's final position I used the nuts on the threaded rods to gently lower the heavy casting exactly where it needed to be. I dry-fit the distributor during this process to get everything lined up perfectly. Once the four nuts lost tension I removed the bracket, threaded the ten manifold bolts in and torqued them all down, four stages to 35 #-ft, in the Ford recommended sequence.
For those who are unaware, most engine builders will recommend that you do not use the cork gaskets for the front and rear seals. Instead, "glue" new gaskets for the sides (between the manifold and the heads) using grey RTV on the coolant passages. Then put a 1/4" bead of RTV grey on the front and rear seals. Let it harden slightly (one hour) then "stack" a second smaller bead on top of it. Place the manifold on and torque down immediately.
The last time I did this I had a strong helper and although we were careful as we could be, the heavy manifold still dug into the front bead of fresh RTV, and therefore it started to leak oil soon afterwards.
This time I rigged up a bracket out of wood and threaded rods to make the installation nearly fool proof. The long member is a 2x4 pine ripped in half. The short pieces are 1/2" x 1-1/4 oak. All are scrap from other projects. I bevel-cut the long member to accept the short ones so they are more-or less at the same angle as the carb plate. The oak gets pre-drilled holes and fastened to the pine with deck screws.
This rig isn't strong enough to break the old gasket seal- I use an axe handle in the front thermostat housing to do that. Then I used my bracket to raise the manifold off the engine, about 1/2" off the front seal and 2" or so off the rear seal by simply turning the four nuts in sequence.
Along with a helper this allowed me to use the "handles" to pick up the manifold, move it back 3/4" to clear the small bypass hose, then lift it out and onto my workbench.
I measured the heights of the nuts on the threaded rods to set the bracket in the same position for the placement, then removed it to allow cleaning the underside. Then I remounted the bracket and used it as a handle to carefully maneuver the bypass onto the short hose, with little chance to smear the fresh RTV. Once I got the manifold hung above it's final position I used the nuts on the threaded rods to gently lower the heavy casting exactly where it needed to be. I dry-fit the distributor during this process to get everything lined up perfectly. Once the four nuts lost tension I removed the bracket, threaded the ten manifold bolts in and torqued them all down, four stages to 35 #-ft, in the Ford recommended sequence.
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