I feel for you, as removing broken bolts has always been a serious P,I,T,A. Since that was a 3/8" tap that broke off, a center punch and a big hammer can fracture and break up the old tap as it is brittle, and not a solid round bolt. You should be able to pick the pieces out, and continue with the punch until all the offending tap is gone. Then with whatever amount of the original bolt is left. Get a left hand drill bit slightly larger then 3/8", I think a 7/16" left handed should get it out. Heat the bolt to melt the locktite, and reverse your drill, the left handed drill will bite into the bolt, and turn it counter clockwise thus removing it. Good Luck.

Jack

 

I think it was the original bolt since I have had the car for 12 years. However my jag mechanic thinks someboby had been in before and loaded it with red loctite! he has never broken a crankshaft bolt before when removing it?
I am now looking at perhaps drilling out all the old bolt and putting in a "time-sert coil after watching crank repair on youtube...
This job is driving me crazy and getting expensive....watch this space!!

 

I am looking at wiseautotools.com for perhaps a Time-sert set for the crank.
My jag mechanic has used induction tool in the past but where you have access to the nut. In our case 1/2 of the bolt is still inside the crank which is the problem. We have tried applying heat with a blow touch to no avail...That bit of a bolt will not budge!! its in there solid, hence trying to tap and then breaking tap!

 

If one takes minimal care during the drilling process the original threads can be undamaged. Then run a cleaning tap thru them (not a regular tap) . A cleaning tap will remove the thread locker, but no metal. A regular tap will remove metal, weakening the “holding” ability.

I do like the time-serts, especially vs. heli-coil. But the best outcome is to need to use neither of them.

Z

 

^ +1

If you have got rid of the tap, and continue drilling that's the way forward, stop drilling before you hit the original threads and collapse what's left of the bolt.

 

When I was a kid, there were plans to build an Electric Discharge Machine (EDM) in Popular Mechanix (or one of the Mechanics magazines...now I'm looking for it.) I actually bought the parts, but never built it...

Anyway, I was excited to read that there are relatively inexpensive EDM machines designed for bolt removal.

Apparently, you can buy one for about $1,500 from a company called Vevor.

However, I have to assume that many local machine shops have such a machine and can remove your bolt ez-peezy. I hope you are able to remove your bolt and will be particularly interested if you have someone use an EDM machine to perform the task.

Now, I want to find that article and finish the EDM build I started when I was 12 years old !

 

Thank you all so much for your input.
I have decided to order a timesert kit 1620 which is 16mm bolt 2.0 thread which is the same as the original jaguar bolt.
Will be installing the kit this weekend and will report back on the results.

 

Be sure to check the time sert data for the maximum torque one can use on the size of time sert being installed.

It should be well above the required torque for the retaining bolt.


Z

 

Good Brotha... Personally, and this is just me, I don't agree with this approach. The crank bolt on these cars ask for some of the highest torque specs I have come across in my short experience working on cars. These aren't stripped out threads in the block for a cylinder head, where there are 9, 10, 11 other bolts sharing the load. It is a single bolts asking for 100s of foot pounds of torque, folks use poles to get leverage to exert proper torques.

Wether you have to pull the engine, or keep working at it how you are, that cracked off tap and that old bolt NEED to come out of that crank snout. It's just that simple. I know it's hard and frustrating... I do

Jus say'n,,, it's time to get mid-evil on that thang...

 

2 people working having decided it is the only direction to go, can have the engine out in 5-6 hours. I imagine the hood is already off the car, rads are out, space has been made.

Drop the steering pump, starter wiring, coolant connects, AC connects, fuel lines, prop shaft etc and get the engine out so you can have a right look and angle on the front of the engine. Sounds extreme, but with the amount of time spent with engine in,,, the engine could be out and back in.

Then try the punch to shatter the bit, then - any or all of the other suggestions for getting that sheared bolt OUT. Ya gotta.

 

I don’t see where the OP is considering leaving part of the old bolt in the crankshaft. It looks to me that he is assuming that the crankshaft threads will be damaged in the drilling process.

I believe this is a rushed assumption. Even with a drilled hole that is off center, it is possible to collapse the remaining bolt once one side of it is nearly drilled out all the way to the crankshaft threads.

The key is to have some very sharp cobalt or better drill bits.

At that point a cleaning tap, as mentioned previously will remove the rest of the thread locker materials without removing any metal.

My fear is that no time sert is rated high enough to take the factory prescribed torque setting without failure. If I’m wrong on that, great, but the time sert specification needs to be looked at very carefully to be certain.

 

PS: it wouldn’t hurt to spray a 1/2 can of CRC Freeze-Off directly at the broken tap and broken bolt area. Use Short bursts until fully 1/2 can is used. I’ve had miracles occur using that product.

note: use in a well ventilated area or with a fan blowing it away from you. The fumes are toxic.

Z

 

I like the idea of drilling all of the old bolt out, but how do you remove the last pieces from the threads? Will they collapse inwards on their own? unlikely....?

 

Yes, that's exactly what you want to achieve.
Drill as large as possible without hitting the existing threads, it doesn't if your hole is not centered, then collapse the remains with a suitable chisel / punch then clean the threads with a tap.

 

a small chisel with a sharp point is used to manipulate and collapse the remainder of the bolt. They come out quite easily once one side of the bolt is away from the crankshaft threads. A cleaning tap and vacuum finishes the job.

Have removed many broken engine bolts this way, starting in the late 1960’s when I worked at a Triumph Motorcycle dealership.

Z

 

I will try to do that, the threads to the rear of the sheared bolt look OK?




This is the latest picture taken today 1/5/2022

Latest picture taken today 1/5/2022

 

I have decided to first try getting the sheared bolt out as suggested.
I am using Tungsten carbide "burrs"? to very, very slowly grind the bolt out from the inside.
So far I am making progress, more tomorrow, thank you all for your SUPPORT, this is not my favourite Job!!!
What size tap will I need to clean out the threads?

Tungsten carbide tips/ "Burrs"?? moving from the pointed one now using the top one in picture, flat sided.

Progress at the end of a hard day! the threads you can see are from when I tried to tap a hole and broke the tap!...moving onwards and upwards....

 

I don’t know the size of the tap, but it’s important to reiterate that one must use a “cleaning tap”, not a standard tap which is used for cutting new threads.

Craftsman sells a nice kit of cleaning taps, I don’t know if the kit includes the size you need. But once you determine the correct size, any quality tool supply house ( not Harbor Freight ) can sell you the correct cleaning tap.

Z

PS looks like you making good progress. Don’t be discouraged if you nick the crankshaft threads in a spot or two. If 95% + of the threads are in good condition you are doing a good job.

Using a sharpened chisel to collapse the bolt once it’s close to being drilled out all the way will keep damage to the crankshaft threads at a minimum.

good luck !

Z

 

Z thank you very much for all your HELP and SUPPORT it is very much appreciated!!

 

Having trouble finding an M16x2.0 Follower/chaser/cleaning tap, would a spiral flute metric tap do the same job? or do I need to cut flutes in the old bolt using my dremel to make a cleaning tap??