Cracked 2f Intake Manifold (17111-61010) with Headers - Can I just add a heat riser block-off plate on the bottom with a gasket? (1 Viewer)

[cdubatl]

While chasing a vacuum leak at the base of the carb I removed it to find a crack in the center of the intake manifold. Looks like it was repaired at some point with an epoxy which partially flaked off. No telling how long ago. I'm looking for an intake manifold but started thinking... is it as easy as adding a heat riser block off plate and gasket to the bottom instead of trying to replace or repair the intake? Would that work?

 

[jayp2]

While chasing a vacuum leak at the base of the carb I removed it to find a crack in the center of the intake manifold. Looks like it was repaired at some point with an epoxy which partially flaked off. No telling how long ago. I'm looking for an intake manifold but started thinking... is it as easy as adding a heat riser block off plate and gasket to the bottom instead of trying to replace or repair the intake? Would that work?

Pull the intake manifold and have the leak welded

Happened to mine, had it welded and never an issue again

 

[GA Architect]

While chasing a vacuum leak at the base of the carb I removed it to find a crack in the center of the intake manifold. Looks like it was repaired at some point with an epoxy which partially flaked off. No telling how long ago. I'm looking for an intake manifold but started thinking... is it as easy as adding a heat riser block off plate and gasket to the bottom instead of trying to replace or repair the intake? Would that work?

If it's a simple crack, want to try and braze the cracked aluminum? If you have a map gas torch (or other gas for that fact), get you some Hobart 770206 brazing rods. I was messing around with some Hobart rods and aluminum pieces not too long ago. I was surprised how simple the process was. Once you get the heat into the aluminum, the rods flows like butter!

Or, I'm sure some near by professional place can do a much better job.

 

[wolfbak]

I had a cracked manifold when I bought my rig. I also had headers and a heat riser block off plate.

When I pulled it apart, gas had collected between the block off plate and the manifold. I don't know how much it affected the engine, but it was some nasty old stinking gas in there. I think it would have degraded the gasket over time and leaked onto the header.

 

[jayp2]

If I recall correctly (it was looooong ago) when I had mine welded they drilled both ends of the crack, something about relieving stress and then welded the whole thing.

 

[cdubatl]

Thank you all. Especially the part about the potential of it filling with gas if using the block-off. I think that answers my question and will pull it to have it done more permanent. While I'm at it might as well pull everything off and replace the manifold gasket while it is half off already.... Simple stuff like changing a carb base gasket always gets interesting with the next 3-4 projects that spawn from it.

 

[PabloCruise]

Thank you all. Especially the part about the potential of it filling with gas if using the block-off. I think that answers my question and will pull it to have it done more permanent. While I'm at it might as well pull everything off and replace the manifold gasket while it is half off already.... Simple stuff like changing a carb base gasket always gets interesting with the next 3-4 projects that spawn from it.

Yep! It is always something "while you are in there"...