Clarkair CA-1 Discussion Board

Photo of manifold from Rusty Acres

Oz

I finally got around to removing the manifold today. The PB Blaster that I sprayed on the nuts worked well. I gently torqued them off with no problem. I was prepared to use heat and worst case dremmel cut the nuts off and if needed replace the studs. Only 4 held the manifold off. As I removed tension on the aft nut I started to smell the distinct odor of antifreeze. That worried me. Before I could get it completely out the manifold came off due to the rust; see pics. When I removed the stud with the bolt the anti freeze came gushing out the hole.

I put the stud back in to evaluate and save the whales from being poisoned by so much toxic waste being vented into our environment . I was not aware that the stud holes penetrate all the way into the water jacket. Can anyone confirm that is acceptable convention? The block is not cracked and I see no damage.

For now I am cleaning things up. being careful not to get crud into the intake openings. I suspect I can blow those out through the spark hole one at a time by advancing the fly wheel until all are clean??

One barnacle and fungus growth successfully removed!



Details of the old repair job. I am lucky no crud has been sucked into the cylinder as far as I know. That would be catastrophic!


Aft stud rusted to the nut!

Someone had asked about the screws in the manifold earlier. Here are the 3 plugs from the manifold. They are 3/8" in diameter and 5/8 inch long. The square nut is 5/16". i'm not familiar with 'pipe threads, so I will have to see what diameter of drill and tap to use to tap the new manifold.

They are probably for a hand primer system that as far as I know was never installed on a Clark

Dr.,
Thanks for the info. It seems all the Clark manifolds have the plugs, but nothing in them. Do you own a CA-1 as well? ANy help we can get on info is much appreciated.

Dry fit of the manifold and carburetor. Re-drilled the carburetor stud holes and everything fits. The throttle valve is free through its full range so there's no valve to manifold contact. painted the manifold with cast blast. I ran all over town looking for a tap to make the screw holes for the three brass plugs that belong where the three flat spots are. By coincidence I found the same plugs at Advanced Auto. They are brass, but they only had one left. They are 3/8 x 20 or 10mm x 1.0. The fuel line is longer than needed to I can make an accurate cut once I mount the manifold and fuel sediment bowl. GETTING CLOSER to seeing it run!

Just got done drilling and tapping the 3 holes for the three plugs ni the manifold. No one sells 3/8 x 20 at stores so I used a 10mm x 1.0 and the plugs fit fine. I used the original ones in stead of buying new.