I found a crack on my Super comp engine's head. It's a bmf 385 and has a crack under the stud boss on an end exhaust rocker. I have T&D's also. I've heard of this happening before, one guy welded his aluminum, then they added to the ends of the T&D stands so they extend to the end of the head and then added a cross bolt going into the end of the extended stand from the front/rear. Then tigged all of the rocker stands together. Anyway we missed finding it over the winter and I'm weighing options, pistons aren't very old and just freshened so I'm not anxious to go into the short block for different heads. What do you think repair or replace?
No matter how many times you paint over a shadow it's still there.
No plugs in the ends. Apparently any of them can have this issue. I've heard of cfe and Dart cracking, apparently brodix castings also. I'm leaning towards new heads. The crank, block, head castings and valves are original to the motor. It might make more sense to just replace the heads. Hi tech welding was also recommended by a friend.
No matter how many times you paint over a shadow it's still there.
I had mine welded up with the exact same problem, and it worked the 2nd time, when they added a bunch more weld material and machined the boss about .100 higher. Been running them a couple of years since then.
Bill Huntington GZMOTORSPORTS.com
gzmotorsports.com/video/PRI2010.wmv
Posts: 163 | Location: Northern Cal | Registered: January 06, 2000
According to the numbers and cfe these are the canfield castings. The new bmf's have added material in the top and will require new T&D stands or mill the old ones. My choices are still to weld these, new conventional heads or a total redo of the engine. I didn't get Chris called today but I still intend to. I was also reminded to check for coil bind, some springs are not as consistent.
No matter how many times you paint over a shadow it's still there.
FWIW, we had a 582 with canfield casting that took out the whole engine due to a crack in the intake runner that leaked coolant into the cylinder and beat the bearing out of it at 400ft out..... just saying.
Michael Frizie ET 2471
Posts: 638 | Location: Winston, GA | Registered: April 10, 2002
Thanks for the input, Chris repaired the heads. The work is beautiful, he showed me a picture of the first weld, it's difficult burning the oil out of the porous metal. It was not pretty, then he worked his magic. I can't say enough to thank him, he explained the process and the end result is amazing. I doubt you would find a nicer of more professional person in the business. There are Canfield castings without the plugs in the end. These are some, it seems the ones with the end plugs might be better than the ones without. The thinking is there may be porosity due to trapped gas in the molten metal when cast.
No matter how many times you paint over a shadow it's still there.