The Ford Barn - View Single Post - SBF tri-power woes

jefeingold · 06-17-2022, 01:21 PM

I've installed a vintage Ford performance tri-power set-up (Buddy Bar manifold) on my 347 sbf. The Holley carbs (dated 1964) are List 2436 (primary) and 2868 (Secondaries). Prior to install I cleaned, re-surfaced to flatten warpage, centered the throttle plates, replaced everything, and generally rebuilt.

Synching the linkage and fabbing an accelerator linkage took some fiddling, but it's now done and correct. The engine starts, runs, and idles well and sounds amazing, but upon warm-up it begins to push clouds of blue/white smoke out the exhaust. It never did that with the former Holley 4160, so I don't think the rings or valve seals suddenly went south; the pvc is fine. All I can figure is that the carbs are dumping fuel into the manifold, since it looks too wet when I peek down the barrels (accounting for the shot by the accelerator pumps). I've even lowered the fuel bowl floats to eliminate the common problem of flooding from overfilled bowls. I cannot see or find any leaks, inside or outside. In addition, I cannot find any leakage on the bench with carbs hooked up to a fuel pump.

I do have a sneaking suspicion that these carbs might be simply worn out (although spraying starting fluid around them I can't find vacuum leaks, even at the throttle shafts).

By the way, initial timing is 15 degrees BTDC, oil is fresh, and pump gas is 93 octane.

Any ideas what's going on and steps to take to sort this out?

06-17-2022, 01:21 PM	#1
jefeingold Junior Member Join Date: May 2022 Posts: 9	SBF tri-power woes - smoking like a chimney I've installed a vintage Ford performance tri-power set-up (Buddy Bar manifold) on my 347 sbf. The Holley carbs (dated 1964) are List 2436 (primary) and 2868 (Secondaries). Prior to install I cleaned, re-surfaced to flatten warpage, centered the throttle plates, replaced everything, and generally rebuilt. Synching the linkage and fabbing an accelerator linkage took some fiddling, but it's now done and correct. The engine starts, runs, and idles well and sounds amazing, but upon warm-up it begins to push clouds of blue/white smoke out the exhaust. It never did that with the former Holley 4160, so I don't think the rings or valve seals suddenly went south; the pvc is fine. All I can figure is that the carbs are dumping fuel into the manifold, since it looks too wet when I peek down the barrels (accounting for the shot by the accelerator pumps). I've even lowered the fuel bowl floats to eliminate the common problem of flooding from overfilled bowls. I cannot see or find any leaks, inside or outside. In addition, I cannot find any leakage on the bench with carbs hooked up to a fuel pump. I do have a sneaking suspicion that these carbs might be simply worn out (although spraying starting fluid around them I can't find vacuum leaks, even at the throttle shafts). By the way, initial timing is 15 degrees BTDC, oil is fresh, and pump gas is 93 octane. Any ideas what's going on and steps to take to sort this out?