Tips on removing bolt from engine mounts.

[KFC911]

In attempting to remove the engine mount bolts this weekend, I reached a conclusion: man those things are on there! My Ingersol Rand 1/2" impact wrench (600+ ft/lbs of torque) wouldn't budge them even after two days of spraying with Wurth's Rost Off every few hours, and applying the wrench. I attached a rubber tube to the can of penetrant so I could better attempt to spray the bolt from below, but so far...no success. Other than being patient, and keeping on 'doing what I'm doing', is there anything else to try? Is PB Blaster any better than Rost Off? On my '88, the bolt screws into engine support (i.e. there's not a nut on the bottom). GRRRRRR....

[KTL]

If it doesn't come loose, you can support the engine (take the load off the support) and then cut the spanner bar near where the bolt sleeve is welded to the spanner. Cut the bar close to the sleeve so you can remove the body mount with the bolt/sleeve combo that is still inserted into the body mount.

The weld typically breaks when the bolts won't come loose. The weld breaks sometimes, just from using the car (engine torque).

I'm surprised the welds haven't already broken from the impact wrench. Next step is to get a breaker bar and a long length of pipe on that sucker. Either the weld is going to twist & break, or the bolt will finally break free. Just be careful with the breaker bar. Sudden release can cause all sorts of mayhem. Like you ending up on your a$$!

Moral to the story? Make sure to use anti-seize paste on the entire length of the bolt (even on the shank/unthreaded area) when you reinstall it.

[KFC911]

Thanks Kevin! I'm gong to need an assistant before I try the 'breaker bar' approach (my longest bar is 5'). I know if I get a 10' length of bar...then SOMETHING'S gonna give...maybe I'll get some football 'butt pads' for protection ! In the meantime, I'm going to continue the penetrant/impact wrench approach for a day or two more...

[ChrisBennet]

Could you cut or drill off the tops of the motor mount bolts and get the engine out that way? If that worked you could then remove the cross member from the motor and have better access.
-Chris

[KFC911]

Thanks Chris! It was my original intention to just do a 'partial engine drop' to remove the rear engine tin and (also install sport motor mounts). Do you (or does anyone) know if the cross member can be removed with a partial drop?

[KTL]

Good suggestion Chris!

Since the bolt and the cross bar/spanner bar look like they'll have to be replaced anyway, why not kill the bolt head first?

How about cutting a few diagonal slots across the top of the bolt head, then shear-off the head with a chisel? I suggest that, only because drilling can get pretty messy. If you drill, be sure to use cutting fluid.

Looks like the bolt, motor mount and cross bar will be the items in need of replacement when all is said and done.

Cross bar can indeed be removed with a partial drop. It's only four M10 nuts and bolts holding them to the the engine console.

BTW, there's a Porsche TSB/ tech tip that recommends the bolts for connecting the cross bar to the console in regards to noise & vibration. Tip says to torque 'em to 40Nm/29 ft-lb

[KTL]

Tech Tip

[KFC911]

Thanks Kevin! Knowing I can remove the cross member with a partial drop does give me a 'plan B' if my current approach doesn't prove successful.

[MobileWrks]

breaker bar always works for me.ONE THING> once you feel it budge,check and make sure that the craoss member is not folding with the bolt....GOOD LUCK....

[KFC911]

Originally posted by MobileWrks
breaker bar always works for me.ONE THING> once you feel it budge,check and make sure that the craoss member is not folding with the bolt....GOOD LUCK....

One question...how long of a bar ? I actually pulled out my 5' bar (pipe actually), and was 'thinking' about using it yesterday, but then I thought: Self, how much umph (is that a technical term...) are you going to need to exert in order to provide more torque than the impact wrench (600+ ft/lbs)? Without an assistant to help, I decided that I would REALLY have to 'get on it', and was concerned with what damage I might inflict if it 'broke loose', or the socket slipped, etc. I have no problem getting a 10' section of pipe if that's what it's going to take (but I'll have some help on hand), so I don't also have to be pulling with every bit of strength that I have. Thanks guys!!!

[MobileWrks]

3 foot bar+ should do the job. Only brake the first push,then impact it off. One more thing....Push,dont pull !..dont use too lone of an extnsion on it either,possibly 3-4 inch from the bolt its self,just enough to clear the rear hatch.(if you can,put the rear wheels on the ground just so it dont shift the car)

[KTL]

Might want to use a hardned impact extension too? I broke three 1/2 in. drive extensions when trying to get the drive axle nuts off my car. Had to resort to 3/4 in. drive to stop breaking tools and start loosening nuts.

[azasadny]

I had to cut mine with a die grinder to get the one side off. Turns out, the bolt was bent as well as the mount on that side. I replaced all parts with new and the car shifts much smoother... Doing the partial engine drop made things much easier to get to.

[KFC911]

Thanks to all of your suggestions guys! Kevin, I've gone to 'plan B' out of necessity after attacking the bolt with my impact wrench again last night...I now have one side free...after snapping the freakin' cross member support ! I AM impressed with the amount of torque the Ingersol Rand 1/2" wrench DOES produce for this to occur ! In hindsight, I don't believe there's any way that I could have generated enough torque with a 3-5' breaker bar to break this sucker loose. BTW, the weld held...it actually broke the cross member adjacent to the weld...here's a couple of pics:


ps: Apparently I can't upload 'large' pictures anymore...I get a message saying that it will 'overload the server'...is there an issue with the 'resizing function' that Wayne implemented a while back?

[ruf-porsche]

Originally posted by KC911
One question...how long of a bar ? I actually pulled out my 5' bar (pipe actually), and was 'thinking' about using it yesterday, but then I thought: Self, how much umph (is that a technical term...) are you going to need to exert in order to provide more torque than the impact wrench (600+ ft/lbs)?

Thanks guys!!!

600 ft-LB divided by 5 ft equal 120 LB. or greater in order to generate the kind of torque from your impact with the breaker bar.

[john walker's workshop]

short of drilling off the bolt head, you just have to break the end off the bar sometimes. there's no good way to get a grip on the bar end with anything to keep it from turning and breaking. my standard 3' snap-on breaker bar gets the job done easy enough.

[KFC911]

Thanks everyone! I guess I was being a bit facetious when I asked about 'how much umph...." it would take. I'll be the first to admit that I don't have 'Popeye forearms', and since I didn't have a can of spinach handy, I'm not the strongest guy in the world either, but.... Just for grins, say I was using a 3' bar...I would need to exert over 200+ ft/lbs (X 3) to equal the impact wrench. That (200+) seems like a lot to me with just using arm strength (while making sure the bar doesn't slip off, etc.)...Now if I could stand on the bar with my 200 lb fat a$$, that'd be a different story. I'm a firm believer in the physics behind it all...I'd much rather exert a 'fair' amount of force on a 5' bar than straining with everything I have w/ a 3' bar...leverage IS my friend !

[john walker's workshop]

an impact wrench often can not snap loose a stuck bolt, where a quick pull with a 3' breaker bar will easily get it moving. you're putting too much faith in the power of an impact wrench.

[KFC911]

Thanks John! I hear what you're saying, and will follow your advice...can't go wrong there

[911pcars]

Instead of the threaded crossbar, I suggest using a a nut and bolt to attach the motor mount to the crossbar (as in earlier 911s).

Sherwood