16
Found a cracked flywheel housing on a 6.7 Cummins this morning
Took a 2017 Ram 3500 apart for a clutch job and spotted a hairline crack near the starter mount. Customer said it was making a weird tapping sound for a few days. Anyone had luck welding these up or do you always just replace the housing?
3 comments
Log in to join the discussion
Log In3 Comments
jesse_green5514d ago
Heard a guy at the diesel shop say welding those housings is hit or miss because the cast iron can warp and cause starter alignment issues. I'd just replace the housing if the crack is near the starter mount since that area takes a lot of vibration. Better to spend the money now than have it come back with a broken starter or worse.
2
the_emery14d ago
Man you know what, I used to be the guy saying "just weld it up and send it" because I figured cast iron is cast iron and a good preheat would solve everything. But honestly, after reading your post it finally clicked why my buddy's tractor ended up chewing through starters every six months after we welded the housing. That vibration thing makes perfect sense now because the weld area gets hard and brittle, and then the whole thing just flexes differently when the starter kicks. I never really thought about how the alignment would shift even a hair, but on those high torque starters a tiny bit off is enough to bind things up. Yeah you totally changed my mind on this, I'll just cough up the cash for a new housing next time and save the headache.
3
harper69311d ago
Hold up, I'm gonna push back on this a bit. I've welded probably a dozen of these things over the years using a gas torch for preheat and slow cool down with a blanket, and they held up fine. The key is to not let the weld get hard and brittle, you need to use nickel rod and keep the heat low so it doesn't turn into a hardened mess. If the crack is small and not right through the mounting ear, I'd say preheat it to a few hundred degrees, weld it, then let it cool off overnight under some insulating sand. A new housing is over a thousand bucks easy, and I'd rather spend 20 bucks on rod and an afternoon.
2