Farm Equipment - Broke off bolt in D15 head

Print Page | Close Window

Broke off bolt in D15 head

Printed From: Unofficial Allis
Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=44384
Printed Date: 21 Oct 2025 at 1:08am
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com

Topic: Broke off bolt in D15 head

Posted By: Harley
Subject: Broke off bolt in D15 head
Date Posted: 24 Jan 2012 at 10:21am

I broke off a bolt in my D15 head trying to remove the thermostat cover. It was seeping just a little because there was already one bolt missing. Now there is two and I am forced to repair it.

What is the best approach. I dont see how an easyout is enough to get out a frozen bolt.

Hate to take the head off a very good engine but I do have a drill press that could really help.

Should I take the head off??

Harley

Replies:

Posted By: jaybmiller
Date Posted: 24 Jan 2012 at 10:32am

best approach..... buy another D-15....hehehe

next approach... drill them out..use NEW, good bits, small,bigger,bigger until it's all gone.Use oil when drilling, maybe a magnet close by to grab shavings ? Slow and steady wins the game.

final approach....take head off, go insidem, use drill press. But you should buy a head gasket first, cross fingers you don't snap off another head bolt !!

I've done #1 and # 2......

-------------
3 D-14s,A-C forklift, B-112
Kubota BX23S lil' TOOT( The Other Orange Tractor)

Never burn your bridges, unless you can walk on water

Posted By: Tracy Martin TN
Date Posted: 24 Jan 2012 at 10:37am

Try welding a washer and nut on it. It should come out with the heat.Tracy Martin

Posted By: Dick L
Date Posted: 24 Jan 2012 at 11:15am

I would drill it out and retap it on the tractor. What few shavings that would get down the hole will not cause down in the block. You should be able to stuff a rag under the bolts to catch most of them.

Posted By: Dave Richards (WV)
Date Posted: 24 Jan 2012 at 12:06pm

Put wheel bearing grease on a rag or paper towel and stick it in the housing under the bolt hole. I find the grease keeps shavings on the rag during removal.

Posted By: Unit3
Date Posted: 24 Jan 2012 at 2:19pm

1 A friend of mine that works at an AC store would tell to hit them afew good licks with a punch first. 2 Spray them with the JB80 and leave them over night. 3 Then drill them out with a reverse drill bit. I took a scrap piece of wood about 2" wide 6" long and cut the ends square. I stood the wood on its edge and just score it in the middle on the ends at the bandsaw. You can run you drillbit against the end of the wood while the long edge of the wood lays again your flat surface. Then you know your drill is square and going right into the center of the bolt. I did this on my UC to drill out old headlight bolts. Worked great.

Posted By: studetom
Date Posted: 24 Jan 2012 at 2:25pm

Heard a lot of good about this. Have not tried it.

http://www.theoriginalrescuebit.com/" rel="nofollow - http://www.theoriginalrescuebit.com/

Posted By: Harley
Date Posted: 24 Jan 2012 at 4:17pm

Thanks for the tips,

I drilled out the first bolt and tapped it. Even though it drilled off center, there was good enough thread to hold a new bolt.

The second bolt was not so easy. The old bolt seems to be harder than my bits. I used new bits and sharpened them too. but they just cant penetrate the hardened bolt.

So what do I do now?

Posted By: RickUP
Date Posted: 24 Jan 2012 at 6:45pm

If there is enough bolt at flush or above, weld a same size washer on it real good. then another larger washer if needed. Then weld the nut to that. Make sure it cools to the touch, put a wrench on it n turn it out. Just more detail,but the same as Tracy Martin's advice. Good luck.

Posted By: Dick L
Date Posted: 24 Jan 2012 at 7:15pm

Sharpen a 5/16 masonry bit. Poor mans carbide. Turn it slow. I have used them in my tool shop in a pinch for many years. You might want to take a 1/8" masonry bit to draw the starting dint on center before the gung ho drilling. That is the secret to getting on center. Keep measuring for center as you draw the starting dint to center. Just take your time.

Posted By: split51
Date Posted: 24 Jan 2012 at 7:23pm

I agree with Rick and Tracy. If the bolt is broken flush, weld a nut to it. The heat will help release the stuck bolt. I had to do that to several exhaust manifold bolts on my 20-35 and it worked on every one of them. The welding will not penetrate the cast.

-------------
1929 20-35 sn17662
B1 w/snow blade
B10 w/sickle mower
B110 w/mower deck
B110 w/tiller
B112 w/grader blade
B210 w/plo

Posted By: stray
Date Posted: 24 Jan 2012 at 8:27pm

I would agree with welding a nut to it. I've found that a stick welder does a better job of heating up the bolt and breaking the rust bond. It is a lot easier than it sounds, if you are comfortable welding you will be suprized at how easy it is.

-------------
1969 190XT series 3

Posted By: BobHnwO
Date Posted: 25 Jan 2012 at 7:51am

I have used a dremel to grind a center recess before drilling.

-------------
Why do today what you can put off til tomorrow.

Posted By: Rfdeere
Date Posted: 25 Jan 2012 at 8:41am

Is the thermostat housing part of the head on a D15 ?

-------------
Randy Freshour,Member Indiana AC Partners,
http://www.rumelyallis.com" rel="nofollow - http://www.rumelyallis.com

Posted By: JeffMOnt
Date Posted: 25 Jan 2012 at 9:06am

Yes it is. I would just do as the other have said and weld a washer to the bolt if there is enough and then weld a nut to the washer. I did this numerous times when I rebuilt my engine as a bunch of the manifold studs broke off when removing it.