Tough Bolt on front of Crankshaft

[chris57]

On the 1275 engine. I would like to replace the timing gear cover. Don't ask why. Suffice it to say that I need to get that front bolt off that holds on the pulley on front of the crankcase shaft. I've tried locking up the rear wheels and beating on the wrench. I've tired heat. It won't budge. If memory serves, it is a regular right hand thread.

Any thoughts? I've actually thought about using the starter motor, with the wrench on, to break it free. Feel free to talk me out of that idea.

Thanks

 

[Gliderman8]

This is how I removed the crankshaft bolt on my TR6. I don't know what your engine looks like but you may be able to adapt this setup...

 

[Trevor Jessie]

easiest way is with an impact wrench. the cheap electric ones from harbor freight will do the job.

 

[JPSmit]

and, the old school way is to feed rope into the piston through the plug hole.

 

[chris57]

Can't fit an impact wrench in there because the steering rack assembly is directly in front of the bolt. I honestly am not even sure if I have enough room to thread it out once it's broken free. But with that thought, maybe I should remove engine mounts and raise the engine enough to both get an impact gun on the bolt and know for sure that the bolt will clear. But before I do that I think I'll try the rope trick. That's clever as ****.

Thanks

 

[dklawson]

CAUTION:

I have used the rope trick many times. I have promoted it to skeptics many times. It does work. Then I got burned by it. I still would use the rope trick but please learn from my mistake.

On our Spitfire I got the engine near TDC on the firing stroke for #1 (valves will be closed). I fed in the rope, brought the piston the rest of the way up, and put a big pipe as a cheater bar on my heavy, long breaker bar. Nothing budged. I pushed and pushed. I got mad and threw my weight against the pipe. I should NEVER have done that but eventually I did get the crank bolt out.

I made the repairs I had planned on and when I restarted the engine it ran terribly. A compression test revealed low values on cylinder #1. A leak down test said there was a leak past the rings. Out came the engine.

A tear down showed that I had put so much force against the piston with the rope in place that the top of the piston had started to shear off and was bent down against both the first and second compression rings. The rings were "gripped" by the piston and unable to move. An unplanned total rebuild followed.

Learn from my mistake. Try the rope trick but make sure you feed the rope into a cylinder approaching TDC on its firing stroke so the valves are closed. Then, don't put ridiculous amounts of torque on the breaker bar to get the bolt out. If you find yourself putting what you feel is excessive torque on the wrench, stop. A good impact gun with lots of air pressure behind it will get the pulley bolt out without damaging the piston. It is more work to pull the radiator and lift the engine to gain access to the bolt with an impact gun. However, in the end it could save you a lot of money.

 

[chris57]

Sage Advice

 

[Deleted member 8987]

Easier than you think. I've posted this before, with the regular round of idiocy emanating from the peanut gallery...until a local (on this forum) with a Spit needed to get the crank bolt out. and myself and Don (DNK) drove over and did it for him.
Find a suitable socket. Find a long breaker bar. I like to use a 3/4" drive, but whatever works.
Fit the socket and breaker up to the bolt, with the breaker bar extending to the left side of the vehicle (viewed from driver's seat), resting on top of something non-breakable, like a frame rail.
Connect battery. Stand clear, hit the starter. Might take two or three hits, but it will walk right out.

 

[chris57]

Thank you everyone for the input. I wanted to try the rope trick simply cause I'd never heard of it and it sounded so clever. I thought about using the battery but decided against it for fear of stripping ring gear teeth. In the end, I simply unbolted the engine mounts, jacked up the engine enough that the bolt cleared the steering rack, and hit it with the air gun. Spun right out like it was never tight. I'm now moving on to installing a new (to me) timing cover with oil separator so that I can introduce pcv to the engine. It's all fun.

 

[Deleted member 8987]

I could probably use an impact gun now...but for 30 years I had a compressor that was..anemic. 100PSI max, silly thing was an old paint compressor feeding a hot water tank. HUGE 110 motor. Now I have 150PSI and it works.

 

[Sarastro]

That's the bolt that motivated me to get an impact wrench and a set of hardened sockets. It took that l'il motha off, no problem! I consider it one of the best tools I ever bought.

All in all, it might be easiest to remove the engine to do this. Or, at least unbolt the mounts and lift it up a bit so the bolt is in the clear, if possible.

 

[histerical]

Mine (1275) won't budge. 1/2" air gun on max and nothing. I am afraid of heat for the dampener which I assume is in the pulley.

 

[bobhustead]

When I worked as a line mech at a BMC dealer we would put a socket and breaker bar on the bolt with some space to whatever the bar would hit and spin the starter.
Bob

 

[Nelson]

FWIW When I was doing disassembly of my suspension I had a nut that I couldn't budge using a Home Depot impact wrench. I went to NAPA and bought one of theirs and the nut came right off.

 

[Jim_Gruber]

Increasing line loss from little compressor.
1) Use shortest length of hose possible
2) Use 1/2" ID Hose not 3/8" Hose
3) Change all of your connections, Quick Disconnects to 1/2"

Doing this you increase your maximum PSI at the gun by as much as 50%. Every time you put an adapter, coupler in place it reduces available Air Pressure.

 

[regularman]

Yes, this works on all cars. I have used that many times. Just be very careful.

 

[regularman]

Yes, this works on all cars (Bobhusted). I have used that many times. Just be very careful.