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| | | | Joined: Dec 2012 Posts: 201 Shop Shark | | Shop Shark Joined: Dec 2012 Posts: 201 | I started to do an engine swap today. I bought a '53 235 to put into my '46 6400. Everything was going smoothly until I realized that the bell housing on the engine is different from what I need. I pulled the bell housing off my dead 235 and that went well. When I went to pull the bell housing off the replacement engine, I couldn't get one of the flywheel bolts out. I tried a breaker bar and an impact wrench with no results. The bolt head is starting to round off and I don't want to break it.
Any suggestions for what to try next? | | | | | Joined: May 2015 Posts: 236 Shop Shark | | Shop Shark Joined: May 2015 Posts: 236 | That is a real bummer. Really hard to get heat and penetrant to it as the flywheel is in the way.
You have tried going toward the tighter side a bit?
Baking in the nice desert sun, breathing life back into a 48 3800 5 window.
| | | | | Joined: May 2001 Posts: 1,904 'Bolter | | 'Bolter Joined: May 2001 Posts: 1,904 | Big heat. Biiiiggg heat. Heat up the flywheel with a propane torch at least trying to keep the heat away from the bolt. Let cool. Heat the bolt itself. Let cool.
Basically, try to exercise the two pieces of metal (bolt and flywheel) one at a time as much as you can. If you can make one expand before the other, you might break the adhesion.
1948 3/4-Ton 5-Window Flatbed Chevrolet 34 Years. Now with a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.
| | | | | Joined: Nov 2006 Posts: 2,544 Shop Shark | | Shop Shark Joined: Nov 2006 Posts: 2,544 | Use a good quality 6 point socket | | | | | Joined: Mar 2004 Posts: 6,212 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 6,212 | Make sure you socket fits tight against the flywheel to get a good bite on the thin headed bolt. Some sockets are beveled for the first 1/8 to 3/16 before the actual hex walls comes into play (this makes it easy to start the scoket on the head of the bolt). I've filed that part off of sockets before to make sure I had the max coverage on the bolt with the socket...it helps by my allowing the socket to walk off of the bolt head. Hope this makes sense... Mike B  | | | | | Joined: Dec 2012 Posts: 201 Shop Shark | | Shop Shark Joined: Dec 2012 Posts: 201 | Thanks for all the suggestions. I got it out today after work. I decided to try drilling it off center to release any tension on the threads. I then changed my mind and went for drilling the head off the bolt and dealing with it later. When I had the hole drilled, the head was still on the bolt, so I put a wrench on to snap the head off. Instead, the darned bolt backed right out! Nice as you could ask. Go figure!
Anyway, on to the next step, pulling the oil pan to check for sludge prior to putting things together. | | | | | Joined: Apr 2005 Posts: 1,971 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 1,971 | I would heat the bolt red hot and smack it with a hammer. Quench it with Kroil several times. Then try to remove it when it cools. If it breaks off after a couple of trys, then drill and use other methods. | | |
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