Flywheel Bolt Removal

[JB91710]

Hi Guys,

I have to remove 8 factory installed flywheel bolts that don't Want to be removed. I heated a bolt and used the $26 factory key and all it did is strip off the teeth using a short ratchet not a breaker bar. I have to remove the bolts from the side as the rear engine is installed. Does anybody know of a Thingy that will grab the bolt from the outside and will grab tighter as you apply pressure?

Thanks,

Jack

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[STiPWRD]

What type of key do these bolts require? It's hard to tell from the photo, but they look like regular hex drive socket head cap screws.

[NAZ]

There are many methods for removing screws and most are dependent on the situation. It appears these are socket head cap screws and that would make sense if you are using a "key" to loosen them. If so, here's where to start.

Using an oxy-actelyne torch with a small cutting tip (easier to get in the close quarters with a 90-deg torch) quickly apply heat only to the heads until they just red on the part closest to the tip. Do not try to cut them off by applying oxygen. Point the tip directly on the head as if you were inserting the hex key (in other words -- don't apply heat from the side). What you are doing is relaxing the head of the fastener to relieve the tension. You want to do this quickly so as to limit the heat affected area -- you don't want to put too much heat into the flex plate or crankshaft. Yes it's tricky, you have to apply enough heat to the head of the fastener quickly and minimize heating the other parts. That's why you are pointing the small tip directly at the head of the screw. Use a ball peen hammer and rap the head of the socket head a few times, again straight down on the head -- not from the side. Most of the friction in tightening or unscrewing a cap screw (bolt) is from the head and thats why you are working on the head to reduce the tension.

Once cooled to touch use a multi splined screw extractor the appropriate size for the socket head. An extractor of this type: https://www.ebay.com/i/292269244609?chn=ps Don't try to substitute a square drive extractor -- it's important to use a multi-spline type. And don't get a cheap Chinese made set. Good tools are expensive. The more you damage the stuck fasteners by using cheap tools that don't work or trying methods that aren't effective the more expensive the repair will be when you have to take the engine to a machine shop. Also, if you try this with the screw hot you will likely strip out the socket head. The fastener has to cool before trying to extract it.

If you don't have an oxy-act torch don't try to use a propane torch you bought at Cheapo Depot -- it's not hot enough quick enough to be effective.

As a machinist I could have almost made a living removing broken fasteners that inexperienced mechanics totally messed up before throwing in the towel. If the method above doesn't work I have many more.

[flynntuna]

Naz, quick question. The technique you describe, will that be the way to remove bolts that has thread lock like red loctite?

[NAZ]

flytuna, it is actually better to heat the threaded portion to loosen thread locker. The good news is you don't need to use near as much heat for this and usually less than that which would cause any annealing or distortion of the parts. A propane torch will work in most cases where the bolted assembly has a small mass. It won't work for large assemblies as they are also large heat sinks taking way too many BTUs to reach a temperature high enough to loosen the thread locker.

The method I like to use requires a TIG/Stick welder. I use a carbon arc rod in the stick welder stinger placed tightly against the fastener. I don't want any hint of an arc. I use the foot pedal control of the TIG welder to gradually apply heat to the fastener. I would not recommend this to anyone who hasn't practiced this method as it's very easy to cause an arc or overheat the fastener. I've used it many times and it helps me concentrate the heat energy to a smaller area. But is much riskier than using a propane torch.

[Dave Howard]

Bolt extractor. Try http://www.blackrocktools.com and search bolt extractor. I used these on a stripped cylinder head bolt on a Honda 250SX ATC.

[SixStar]

https://www.importimageracing.com/pr...saAqAsEALw_wcB