The Stovebolt Site Forums The Shop Area Engine Shop What size bolts are needed to remove crank pulley?

I have a 1955.1 GMC 248. I am trying to remove the balancer. What size bolts do I need to attach the puller to the balancer? The two bolt holes were full of grime, so I cannot tell if I have the wrong size bolt or there is still grime in there. Every bolt that i have tried with the puller kit does not thread easily. I am paranoid that I will strip out the threads. Can you tell what the threads are so I can be sure I have the correct size bolt?

I'm not sure about the GMC, but the puller holes ov the Chevy balancers on the 216/235/261 engines have 3/8-16 threads. Try chucking a bronze rifle cleaning brush of about .45 or .50 caliber into a variable-speed cordless drill motor and run it at slow to medium speed with plenty of penetrating oil like PB Blaster or Kroil to clean up the threads. You might need to run a tap or a thread chaser into the holes to get bolts to engage properly.

Once the puller is attached, be sure you're pushing against the end of the crankshaft. I like to use a deep socket that will slip into the front of the balancer for the puller jackscrew to push against.
Jerry

I had some 3/8 all thread in the junk pile. I gently worked it in an out with PB blaster until the all thread screwed in. I then used nuts to attach the puller. Long term, I might have to drill the holes and retap to the next bigger size though. I buggered up the threads a bit before I asked for help here.

The end of the crankshaft has a cone shaped indention in it. At least, I think that is the end of the crankshaft. My puller has a matching cone shape end on it.

So how to I get this thing to start moving? The crankshaft just spins. I tried smacking the cheater bar with a hammer, but that did not thing. The engine is on a stand. I ordered a set of impact sockets tonight. I will try an impact driver later in the week.

Clamp a pair of vise grips on the flywheel ring gear and let it stop against the block. If the flywheel is already off, screw a couple of bolts into the flywheel mounting holes and use a pry bar to stop the crank from turning. The simplest way is to use an impact wrench on the puller after lubricating the puller jackscrew liberally with anti-sieze compound. You can also use a big crescent wrench on one of the legs of the puller. If the oil pan is off, wedge a piece of 2 x 4 between a crankshaft counterweight and the oil pan rail.

"This ain't rocket surgery!" You gotta be smarter than a dumb chunk of cast iron!
Jerry

I thought this morning about attaching a piece of Unistrut to the back of the crank so it hits the engine stand and cannot turn. I then became lazy and did not want to go find the Unistrut scrap in the shed.

Unistrut saved the day. Balancer came off just fine with the big cheater bar.