HeliCoiled Starter Bolt / Cracked Bell Housing

[snoman87]

Any issue with helicoiling a starter bolt? I tried to reverse drill the one closest to the bell housing in hopes it would back itself out ... no such luck. Now I am looking at the helicoil option and thought I would ask how reliable that would be. Not that I see any other choice.

Also, The bell housing and front support bracket where cracked. My plan is to get the housing re-welded and get a new bracket. I don't think it's in a structrually critical location so I think it should be fine.

Any thought what could cause it to kick the starter like that? Bad injectors?

Thoughts, opinions, or other options welcomed at anytime

[ZZ]

I had to use a helicoil on a starter bolt on a 6.2L that was in a '83 Chevy van. It worked well. I even had to replace the starter and it held a second time at least till I sold it. My starter bolt broke because I was lazy & ignorant and left the front bracket off. Needless to say that I put it back on afterwards.

[snoman87]

Ya I made the same mistake with the support brackert on my 6.2TD ... now the bracket is in :)

This one had the bracket and appears to have snapped the stud that's supposed to be on the starter.

[john8662]

Have you tried drilling a smaller hole into the broken off stud and then driving an easy-out into it to remove it?

Soak with thread penetrant before this attempt, but could work, and save drilling the hole larger, tapping, and inserting helicoil.

J

[snoman87]

I actually tried and easy-out but it was the wrong one for the 1/4" hole I drilled. I found the right one in my tool box and will try it first next time. I am not holding my breath that it will work though!!!!

I eventually have to pull the tranny to get the bellhousing loose to repair the crack so if the easy-out doesn't work I will have much better working conditions to attempt the extraction and helicoil if necessary.

[MTTwister]

PB Blaster. Spray, soak, tap with hammer, repeat.

I got a frozen upper A-Arm bolt out of the Duster this way. Took 2 weeks, unfortunately.

[Dr. Lee]

The helicoil will work fine. A lot of race engines are built new with helicoils in critical areas because the helicoil will hold better than the iron or aluminum casting.

When I was learing how to keep the alternator V-belt (Yes you young punks, early GM diesels had V-belts, not serpants coiled around the front of the engine) from glazing and breaking, I overtighted the alternator adjustment bolt and stripped the threads in the aluminum. I helicoiled the alternator about 6 years ago, and have not looked back. Works great.

[ronniejoe]

I think we need to figure out why the bell housing cracked in the first place and fix that problem. Aside from that, yes, the helicoil will work very well if installed properly. Keenserts are even better...:)

[Craig M]

Have had two different broken starter bolts with 6.2's. Both came out very easily with easy-out once hole was drilled in the broken stud.

[snoman87]

Never heard of Keenserts ... I agree with you about figuring out what caused the problem.

Is it at all possible that leaking injectors causing a loud noise during cold starts could be the cause. It's hard to explain but it's noisy and sounds like knocking and has been suggested by multiple sources to be multiple bad injectors. Could that have caused a big enough kick back to brake the bolt and housing while starting this truck. It runs fairly smooth once it's off high idle.

[john8662]

It can also be from oil getting past the valves causing a knock during startup due to bad seals. Believe me, it's true, but not as common as it is on SBC gassers.

J

[Robyn]

One of the biggest causes of starter bolt breakage on the 6.2/6.5 engine is the dificulty of replacing the front starter support that results in folks leaving it off. These engines take a load of torque to turn them over as compared to even a big inch Rat, The result is a great moment of inertia on the starter bolts that finally breaks them. The front starter bracket can be reached easily by removing the right front wheel and going in throught the access hole that is normally coverd with the rubber weather flap on the later trucks. The earlier trucks are much easier as there is no issue with the exhaust. (Turbo down pipe)
Helicoils are great as has been pointed out already.
The engineers did not spec out that little front bracket just because it looked kewl, it is needed. Both my 6.5's had them missing but not any more.

[Robyn]

Been thinking about the bell housing crack??????????/
Did that rig have the large stiffener bar that bolts on the right side of the transfer case and runs up to the bell housing.
If it has been taken off this is the most probable cause of the breakage.
I have seen many rigs that they are missing on. My 86 dually is missing the thing but I was able to scrounge one up.
I am not as familiar with the set ups on the manual trannies as with 350's/400's and 700's but I will bet that someone has deleated some of the bracing. The auto's have the two bars that come down from the motor mounts up front and tie into the lower area of the bell housing cover too.
Radial cracking in the area you have shown in the pix is due to torsional stress in the gearbox trying to rip loose from the engine. The stiffeners will stop this. Rigs used on the highway under reasonable conditions can live happily without the bars but if you start using them rough or off road things will break.
Hope this sheds some light on the issue
Robyn

[hoot_223]

I bored mine out to a 7/16 NF bolt Grade 8 for my 6.2 starter

[Robyn]

The 7/16 bolt is not a bad idea for sure. The stabilizer on the front of the starter is a real must though as it takes a load of the stress off the bolts and the aluminum starter nose cone.

Robyn

[snoman87]

I like the 7/16th Grade 8 bolt idea. Correct me if I am wrong but I should be albe to simply drill the holes out then tap the block and bolt it back together, will I have to drill out the starter holes also?

The starter bracket was present and cracked.

[Robyn]

check the starter with a 7/16th bolt and see if it will go through. If it fits your in good shape and if not get out the drill and oversize the hole a tad.
Couldnt be easier

[snoman87]

that's what I am thinking ... easier and a little stronger