Cummins 6BT 5.9L-M starter removal

Two different diesel mechanics have attempted to remove the starter. They found the bolt heads of all 3 bolts stripped by a previous installer. Two bolts have been removed but not the one next to the engine even after dismantling the starter. They have presented me with two options:
1. Attempt to cut the starter off the engine
2. Remove the engine from the vessel, if option #1 is not successful
I would appreciate the opinions of the TF members.
Thanks

A PIX of the bolt would help.

if the bolt goes through "ears" on the cast starter housing then cutting the ear off and removing the starter would give more access.

I assume that this is the same starter from your other thread but you didn't mention a rusted in place bolt.

bayview said:

A PIX of the bolt would help.

Click to expand...

Please define a "PIX."
Thanks

bayview said:

if the bolt goes through "ears" on the cast starter housing then cutting the ear off and removing the starter would give more access.

I assume that this is the same starter from your other thread but you didn't mention a rusted in place bolt.

Click to expand...

Yes, same starter.

If that inside bolt is not coming out by normal means, then you may have to destroy the starter to get it out. A Dremel tool to cut a groove in the mounting flange, and then a big hammer and chisel to try a break flange, be nice if it was cast but is probably aluminum. If you can get it to break than the starter is out of way, to work on remaining bolt. If I was doing it, it would not be a good time to have grandkids around..

Sometimes a slightly smaller socket on extension can be hammered onto the screw head through an extension. The hammering tends to loosen bonds too. Try that first.

Failing that, cut the starter apart with a grinder, chisel, hammer, whatever. Patience and persistence will get it.

No way would I pull the engine for that.

Lots of ways to remove bolts, most of them tedious and hard work. Can't comment further until we get pictures (pix).

Imo. They can't be much of a mechanic if they don't have the tools or knowledge to remove the bolt.


They sell a bolt extractor that looks like a socket. It has spiral tappered splines on the inside. You pound it on with a hammer then use a socket or wrench on the outside of the extractor. Second option is to use aircraft drills to remove the bolt head. If that doesn't work then cut off tool. Airsaw,sawzal, gas axe ect.

If you can get a 6 pt socket onto the remaining bolt, it may help to try to tighten it rather than go for backing it off right away. There may be enough purchase on the bolt to move it & break it loose, then try to back it out. Always helps to try to crack a bolt tighter before attempting to loosen it.

Better living thru Chemistry.

A soaking for a week with PB Blaster or your favorite might help.

Rust in, the bolts could mean a partial sinking , so you may need a starter yet.

Sometimes a quality (not Chinese) set of Vice Grips can be ground down to fit to grab a bolt head.

Good hunting!

You could also weld an oversized nut to what's left of the bolt head.

Pix = Picture(s)

Most real Cummins Mechanics know that the starter bolts are special and require a 10mm 12 point socket. It is the only 12 point socket needed on the entire engine.
I have one taped to the lid of my tool box labeled for starter removal.


They come out easy as pie with a couple of extentions and the RIGHT socket.


Order 3 new bolts for the install if the ones you have are damaged.

this is the style socket we use on cats. our are 1/2" or 5/8"


https://www.amazon.com/Steelman-Pro...1549122318&sr=8-5&keywords=10mm+swivel+socket

The Other Gary said:

Most real Cummins Mechanics know that the starter bolts are special and require a 10mm 12 point socket. It is the only 12 point socket needed on the entire engine.
I have one taped to the lid of my tool box labeled for starter removal.


They come out easy as pie with a couple of extentions and the RIGHT socket.


Order 3 new bolts for the install if the ones you have are damaged.

Click to expand...

If this is correct, then I would visit a tool truck. Get one 10mm spline socket and one 10mm spiral socket. These sockets are designed to work on damaged bolts.

It is possible that some one has created an undersized head which might require some reshaping with a dremel tool. Of course to do this you might have to destroy the starter to make room.

Pictures of starter bolt

High Wire said:

Pix = Picture(s)

Click to expand...

Got it; pictures attached.

The Other Gary said:

Most real Cummins Mechanics know that the starter bolts are special and require a 10mm 12 point socket. It is the only 12 point socket needed on the entire engine.
I have one taped to the lid of my tool box labeled for starter removal.


They come out easy as pie with a couple of extentions and the RIGHT socket.


Order 3 new bolts for the install if the ones you have are damaged.

Click to expand...

Exactly! I have one as well, for the exact same reason!

I’m with others here, if the bolt head is truly stripped there are several methods to remove it, even if you have to as others have indicated destroy or take apart the starter to get more access.

I think the OP is discussing the third bolt which is behind the starter. No access to it at all except through an extension.

This is one of the style extractors I keep on my truck. They should work for what the op is needing to do.



https://www.amazon.com/Socket-Damaged-Extractor-Remover-Locking/dp/B01GO83YTK

DLETF said:

Got it; pictures attached.

Click to expand...

As you can see it is 12 point bolt head. 10mm

Get a socket and label it for the future, don't depend on your mechanic to know
what is needed. He may mess your engine up before admitting that he did not know.

The Other Gary said:

As you can see it is 12 point bolt head. 10mm

Get a socket and label it for the future, don't depend on your mechanic to know
what is needed. He may mess your engine up before admitting that he did not know.

Click to expand...

Right, the wrong socket is being used. It's essentially a male Torx fitting.

yes male Torx

https://www.walmart.com/ip/11-Pc-To...=sem&msclkid=6fcce30580821e2df6b8bf5297f6a25a

No it is not a Torx head. It is a spline drive bolt, the proper socket is a spline drive socket. Using a torx socket or a regular SAE socket would be like using an Allen wrench in a torx fastener — it might work, it might destroy the fastener.

Yep, 10mm 12pt spline drive. Not Torx. Some cheap sockets tend to round them off.

Ok learned something new. never ending evolution of socket shapes.

What is the purpose of the spline drive bolt head other than overloading tool boxes?.

It’s to keep non factory trained personnel from performing incorrect maintenance.

Actually spline drive allows more torque than 12 point before failure is reached.

I have to say, that bolt does not look like a spline drive to me. The picture is not adequate for me to say for sure what it is and I don’t know for a fact what it is but it looks a lot like a reverse torx plus head. Yes there really is such a thing. It is similar to the MORFOR head that Ford uses on its truck beds.

Would be nice if we had an actual spec. From Cummins.

No. It's not to keep people from working on it. They use 12pt bolts on the starter for clearance. No room for the socket or wrench if you could even get the bolt in.

THere is a 12 point head bolt , not spline, not torx. I have run into them before and a 12 pt socket or box end wrench fit them perfectly.

On my V555 Cummins engine are some of those 12 pt bolts but 7/16. Done for clearance purposes and also in my case because some of the bolts you literally can only turn the fastener one point at a time, 30o , which makes the removal a long drawn out process.
To get those bolts one must have the specific wrench needed or the unit is not coming off.

Maybe something else would fit but as Ski pointed out maybe monkey the bolt head causing serious trouble for removal.

BIG CAT said:

No. It's not to keep people from working on it. They use 12pt bolts on the starter for clearance. No room for the socket or wrench if you could even get the bolt in.

Click to expand...

12 point bolt is the same as 6 pt bolt in respect to clearance. In other words 10mm is 10 mm regardless of points. 12 point does allow more torque before failure when tightening.

I was being funny about the qualified mechanic