Broken starter bolt

I was having problems with starting my m1009, got underneath to check starter and noticed a bolt laying on the ground. Looked at starter and noticed the inside bolt was broken. I took the starter off and then noticed that the bolt hole had a helicoil already installed and that the bolt broke flush with the mount. My problem is that I can't seem to get the drill in place so I can drill the broken bolt out. 1.) How can I get the drill in there so I drill broken bolt out? 2.) Is there any foreseen problems since there is already a helicoil in place? Any advice would be helpful. Luckily this happened at home.

Get some high quality drill bits. Start as centered as you can. I used a 1/4" drive socket which fit into the bolt hole to center a 1/4" bit to make a center depression, then switched to a 1/8" bit to drill the pilot hole. After a bit of hard drilling, it was big enough for a bolt extractor.

In your case, don't worry about the Helicoil. It shouldn't come out, if it does, just insert a new one.

If that doesn't work and you have a high pain tolerance. Remove the starter, clean up the bolt shaft and try welding a nut to it. A 3/8" nut welded on the inside should keep you from getting anything on the block. I would also suggest holding the nut with the welding ground lead because you do not want to have current running through your engine. A mig makes this a easy process. I wouldn't try it with a stick. There shouldn't be much tension on the broken bolt, so it should just twist out once you can start it moving.

If the drill and weld don't work, try cutting a slot in the bolt with a small cut off wheel, hack saw blade, hammer on a sharpened punch, etc... This will allow you to try a screw driver on it. A hammer impact screw driver might help this effort too.

Remember, You Always Have Other Options. (YAHOO) They just seem to get more expensive as you go.

i had this happen a couple of times on my CUCV.. get a REVERSE drill bit (bolt extracter) it doesnt have to be very big, but it will drill into it a little bit, then grab it and back it out... make sure you get NEW bolts from the dealer (or factory GM parts) or you will be doing it again (ask me how i know )

I had one of mine break off 2 years ago.Lucky for me it broke off flush.Was able to get it out with a centre punch and a hammer.

Is the broken bolt a starter bolt with the knurled section or just a regular bolt? I'm just wondering what thread pitch the helicoil is.

If you can't get a drill in there, how about a Dremil tool? Might need the flexable shaft.

Also does you starter have the front suppoost bracket?

Diesel starters and no support bracket equal broken bolts or blocks.

Thanks for the replies. It does have the support bracket in the front. I did purchase the starter bolts from the dealer, bought four of them to have extras if this happens again. I plan on tackling this again when ever the rain lets up enough where I can get out there and work on it. I don't have a garage or shop to work in. If I run into any other problems I will ask again. Thanks everyone.

I had the same thing happen and was able to drill it out and get and extractor in there. I HIGHLY suggest that you wear a face sheild when drilling!! Gravity will work quite well when doing this!! Safety glasses can allow the shavings to get under them and into your eyes. Neither Safety glasses nor goggles will protect your face from the shavings that might be a bit warm. Just had a guy come throught the ER from such a problem. He lost sight in one eye being Mr. Tough Guy and not using the face sheild he had an arms length away.

I finally got a chance to work on getting starter bolt out. I used a center punch so I could keep the drill bit from jumping, when I moved the punch out of the way I noticed that the broken piece had moved further in the hole. I attempted to use the drill, but as I started to put force on the bolt it kept moving further up. Does anyone know if the outer bolt hole goes all the way through on the outer bolt? If it does I will just see if I can finish punching it out the rest of the way. I also noticed that the helicoil that was in there has stretched as this was happening. I figure that may have something to do with the problem. I'm trying not to damage it.

+1 on the reverse (left hand) drill bit. Works like a charm for me every time. Another must-have tool for this job is a set of transfer punches to mark the exact center of the bolt. And yet another handy tool is a 3/8" end mill. You can chuck this in your drill and make a nice flat surface on the broken bolt. They usually leave a jagged piece that is hard to get a punch on.

I'm working on this right now on a neighbor's M1009. The starter through-bolt sheared off, and without good support from the bracket, the two starter bolts broke. anyone have the part number for the through-bolt? This is a direct drive starter. Thanks.

You're in luck, I just bought a set of starter assembly studs off "equipmentpartssales" on ebay to have as spares. They have 10 sets left. Part #1975326, $18.00.

Hasdrubal said:

You're in luck, I just bought a set of starter assembly studs off "equipmentpartssales" on ebay to have as spares. They have 10 sets left. Part #1975326, $18.00.

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Excellent; thank you!

Went to four auto parts stores. ask for GM part # 15544950 BOLT,CLOSE TOLERANC . None of them could look it up and all just went to the blister pack aisle and pulled a package off the shelf that said GM bolt. Yes its metric but they all are about 1/4 longer than the one that came out. How deep are the bolt holes?

Amazon carries factory GM (acdelco) starter bolts. They come in a box of 5

It doesn't look like it on amazon, but they do come in a box with 5 each. I ordered 4 and now have 20 each. They also aren't that yellowish color but are the right ac deco part

riggermedic said:

It doesn't look like it on amazon, but they do come in a box with 5 each. I ordered 4 and now have 20 each. They also aren't that yellowish color but are the right ac deco part

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I just looked
Yes they do.
ACdelco part.
$5.99 for a box of 5

My other post said factory GM, but I meant acdelco.

Well I did not want 10 of them so I only ordered 1 but nowhere could I see it says box of 5 hope its a box of 5.

Always buy extras because they are torque to yield, which means single use. If you take them off, throw them away and replace with new every time.


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tbearatkin said:

Well I did not want 10 of them so I only ordered 1 but nowhere could I see it says box of 5 hope its a box of 5.

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It doesn't say I know

but when I did a thread search, SS members mentioned that they come in a box of 5.
Ordered 1, 1 box arrived with 5 bolts inside.

Good to go!

and only 1 bolt not 1 box so had to order more.