Replace this bolt?
 

Should I replace this bolt? My starter died and I have a good junkyard replacement (bench tested at an autoparts store). Is this bolt too far gone to hold the 32 ftlbs of torque it will need? It looks like three threads are good and clean going into the transmission bell housing. But a couple are flattened, as you can see in these low res photos. Why are a couple flattened? How does that happen?

https://ecomodder.com/forum/attachme...1&d=1548123569

https://ecomodder.com/forum/attachme...1&d=1548123594

https://ecomodder.com/forum/attachme...1&d=1548123606

It doesn't look that bad but that's pictures for you.
If there is any doubt replace it with one as least the same strength rating.
A metric starter bold is probably 10.8 rated. Don't replace it wian 8.8 because it will snap.

If it threads in easily then I suppose I'd use it. Anything other than the smallest binding and I'd chase the threads in the block and the bolt and/or replace it.

I learned this the hard way. Swapping a car from rear drum to discs once, I cheaped out on the mounting bolts since they were missing from the (used) calipers I bought. Of course, one snapped putting them in. Won't do that again.

I'm with the others. Looks good enough to me. As long as it doesn't bind like Frank said.

I’d use it unless it binds up on its way in... the head studs got nicked up as I lifted the head off my LSJ and I used them over (ARP is reusable though) and was fine

Would any of you use anti-sieze on the bolt, or something similar? I imagine a danger would be that the bolt backs out on it's own. I worked on removing the second, lower starter mounting bolt, which is longer and I think extends through bell housing into the block. It is also fighting me. I hit it with PB Blaster and removed some stuff for room. With a cheater bar I get slight movement, but I am worried maybe the bolt head is breaking off. Ugh. I expected this little job to be simple! Now I feel like the car is off the road for a while.

I probably would. I've never had a problem with anti-seized fasteners backing out.

That's good. I just tested the bolt in the whole again and it does bind up after awhile. Pretty badly too. I'm wondering now if maybe when I did the transmission swap, if maybe I didn't clean out the whole is well enough. I was much newer at all of this back then. Maybe I really screwed up without realizing it until now. We'll see!

broke the bolt in the block
 

Gave it some more PB Blaster and went in as gently as I could to try and remove the bolts but it broke. This is the long lower Bolt because through the starter mount through the transmission bellhousing and into the engine block. At least I know now why my starter wasn't working anymore. The gear teeth raw shredded. It did a little damage to the flywheel too.

https://ecomodder.com/forum/attachme...1&d=1548203008

I'm looking up videos for removing the broken part of that Bolts from the engine block, and because of how awkwardly placed it is if I can even get the bolt out at all I'll need to pull the engine out of the car.

Here comes fun! Eric the Car Guy to the rescue?
https://m.youtube.com/watch?v=c-VD1yx61bA

My condolences. :(

You make it sound like a funeral! �� After mourning it yesterday a little like a death in the family, I am beginning to rally a little bit. There are two plans I'm considering. The first is to use just the one of the two mounting bolts for a little while until I get more time to pull the engine at least partially drill out and chase the threads in that hole. The second idea is a little better maybe in terms of durability. I could perhaps use something like Loctite or steel stick to just set a stud into the hole and secure the starter motor with a nut at the end. The first idea I saw on an on a Honda website, and the second was a suggestion of a good friend of mine with considerably more experience than I have.

Which idea would you prefer? I can see pluses and minuses to each strategy.

Not being totally familiar with the set-up, I'd avoid using one bolt; things might shift and rip more stuff up.

Not a fan of glues and other band-aids either. Gotta drill it out and re-thread or Heli-Coil it.

I agree that one bolt is a bad idea.

Maybe try tapping threads into the trans case and use a shorter, but thicker bolt. Maybe 12mm or 7/16 threads? While the bolt should go into the engine block, I think it'll be OK if it doesn't. You'd probably have to enlarge the hole in the starter for the larger bolt.

Or have the broken bolt side of the starter welded to the trans case.

Or always park on a hill! :D

I don't know if adhesives alone would hold up very long. Another option might be drilling a hole from the top of the trans case through the stud and putting a small pin or bolt through the stud.

I appreciate the caution. I don't like the idea of a bandaid as any permanent fix, either. But this is my daily driving car and I need to have it back and I don't have time right now to get deeper into this whole thing with all the work and family demands upon me. ...so if I could get away with 2 or 4 months maybe bump starting the car on a hill every chance I get to minimize the starter use... that would be a really key Band-Aid right now!

So I've been looking into tests of these adhesives. The Permabond and Loctite products seem to be the strongest. I just need them to provide some assistance stability for this temporary fix. The real restraining bolt will have to be the other OEM bolt that is still good. Between the Band-Aid the OEM Bolt in the bracket that the motor is inserted through to the flywheel, I should have a lot of stability in the short-term and I can keep an eye on it.

But I ordered both replacement Bolts from Honda. If I have to I'm going to take this thing off the road for an extended period of time and drill out the rest of that bolt, Helicoil it, and install the replacement.

left hand drill bit if you can get to the bolt hole. Just might unscrew the broken piece.

There is no way to see into the hole in order to judge whether I'm drilling directly. I could easily ruin the threads or widen the hole. and even if I could go straight in without pulling the engine out of the engine bay, the bolt was fighting really madly badly when it broke. So I have to think that centimeter of threaded bolt that is stuck down there is in really hard. And I mean really hard.

fabrication (nothing fancy)
 

A couple pictures of the 3-6 month temporary starter motor mount that I'm "fabricating." Here you can see the bolt I broke next to the stud and nut from which I'm making the replacement. I'm going to use Loctite Metal/Concrete adhesive to hold this stud into the transmission bellhousing and secure the starter motor in place with the nut. With a little trial and error I stepped up from the 10 mm OEM bolt size to this 7/16 stud size, which is equal to about 11.11 mm. It fits the hole for the OEM bolt almost snuggly so I'm hoping it'll let the adhesive make good contact with the bellhousing.

https://ecomodder.com/forum/attachme...1&d=1548558590

https://ecomodder.com/forum/attachme...1&d=1548558601

how i spent an hour tonight
 

I test fit the new upper mounting bolt that I got from Honda yesterday, and applied a little anti seize to the threads. Good news. The upper mounting bolt slides in without any binding. So I proceeded to producing the lower mounting stud using the Loctite metal concrete and the stud that I got from the hardware store.

https://ecomodder.com/forum/attachme...1&d=1548640159

https://ecomodder.com/forum/attachme...1&d=1548640171

That's a pretty good idea, as far as better than band-aid solutions go.

It has been all bolted up for a couple days now. Running well. Starts well. No sounds of grinding or anything else undesirable. And I couldn't even fit that both over the stud. Unfortunately when I stepped up the size of the stud to fill the hole for the bolts better for stability when the motor is cranking I neglected to consider whether I be able to get a ratchet head on to the nut to tighten it down. Anyone know especially narrow short nuts that can fit over a 7/16 in stud with fine threads? I don't know I don't know if it matters that much since it's working fine and I only intend to hang on to it for a few months this way before pulling the engine and drilling out the broken parts, but it's an interesting detail to try and resolve and I might learn something.

Fine thread might mean using an aircraft jam nut which is 1/2 high, or make your own with a hacksaw. Install uncut side towards load.

Something like this?

Item # NAS509-5, Drilled Jam Nut On Wicks Aircraft Supply

That is the critter. Not full load bearing but 5000 lbs in shear might be enough