tap stripped hole?

Reply

  #1  
Old 01-04-13, 02:56 PM
sgull's Avatar
Member
Thread Starter
Join Date: Nov 2007
Location: AK
Posts: 2,910
Received 1 Vote on 1 Post
tap stripped hole?

One of the holes where the crankcase cover bolts into on my pressure washer engine is apparently stripped (where finger is pointing in photo). I took the bolt out and looked at it; the threads on it are not damaged so I'm fairly certain the threaded hole (where finger is pointing) is probably stripped. I can turn the bolt only so tight then instead of tightening it just keeps turning. With little to none experience tapping/rethreading holes, I'm hoping to get some advice on how to go about this, with what size tap etc, and the procedure using a tap on such a hole as pictured. Any tips/advice appreciated.
http://i207.photobucket.com/albums/b...ps03c09bbc.jpg
 
Sponsored Links
  #2  
Old 01-04-13, 03:38 PM
Halton's Avatar
Member
Join Date: Nov 2012
Location: Canada
Posts: 337
Received 0 Votes on 0 Posts
.


Unfortunately.....there's is not much meat there to go with a bigger hole and thread or to
even try a heli-coil. If you go that route the ear may then end up cracking or breaking off.

You could get a longer bolt and file down one side of the head enough to slide it in from
the other direction, and then put the nut on the outside.

Just throwing it out there.....other people may come along with a better solution.


.
 
  #3  
Old 01-04-13, 03:45 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 59,865
Received 1,205 Votes on 1,115 Posts
Been in the same predicament.....
Drill the hole thru, use a longer bolt and put a nut on it.
 
  #4  
Old 01-04-13, 03:46 PM
H
Member
Join Date: Nov 2011
Location: USA
Posts: 11
Received 0 Votes on 0 Posts
If you want to keep the same diameter bolt, try using a "thread insert" like Helicoil. You will still have to drill and tap the threaded hole oversize, but, the hole in the mating part will not have to be enlarged.

Usually, you can find Helicoil kits at your local autoparts store.
 
  #5  
Old 01-04-13, 03:59 PM
sgull's Avatar
Member
Thread Starter
Join Date: Nov 2007
Location: AK
Posts: 2,910
Received 1 Vote on 1 Post
Here's a picture of the other side. http://i207.photobucket.com/albums/b...psadad346f.jpg The shaft of the bolt is right up there next to the housing, so I don't think it'd be possible to thread a nut onto the end of the bolt. If I was to try a "thread insert" like Helicoil won't I still have the problem of there probably not being enough meat (as mentioned) to enlarge the (ear) threaded hole?

 
  #6  
Old 01-04-13, 04:09 PM
GregH's Avatar
Super Moderator
Join Date: Jan 2001
Location: Manitoba
Posts: 10,146
Received 39 Votes on 37 Posts
IMO it would appear to be better to use a nut and bolt rather than a helicoil.

I believe there would be enough room for a nut if you were to carefully grind down the two ribs that are adjacent to the hole.
If still a bit tight you could downsize the bolt one size and use a grade 8 bolt and a washer on the front side.
Downsizing one bolt size would make it unnecessary to drill the threaded part larger.
 
  #7  
Old 01-04-13, 04:11 PM
Halton's Avatar
Member
Join Date: Nov 2012
Location: Canada
Posts: 337
Received 0 Votes on 0 Posts
.


That's why I suggested what I did. It would be easier and stronger to file the head of the bolt....just enough to clear......and slide it in from the opposite direction that it was originally. Then put a lock nut on the outside.


.
 
  #8  
Old 01-04-13, 04:23 PM
T
Member
Join Date: Oct 2012
Location: USA
Posts: 614
Received 0 Votes on 0 Posts
JB Weld claims you can drill and tap the stuff like metal, never tried it that way though. There is also an aluminum brazing rod called Alumiweld that you can build up the hole then drill and tap but might be tricky here.
 
  #9  
Old 01-05-13, 01:41 PM
sgull's Avatar
Member
Thread Starter
Join Date: Nov 2007
Location: AK
Posts: 2,910
Received 1 Vote on 1 Post
http://i207.photobucket.com/albums/b...ps18e18046.jpg
I got a new bolt, one size down but a little longer than the original (to avoid having to drill the threaded hole in the ear larger and so I'd be sure to have enough thread on the end of the bolt to use a lock washer with a nut). I ground down one side of the head of the bolt just enough to clear and then slid it in the opposite direction than it was originally, and then put a lock washer and nut on the other end. Seems like it should work fine. Didn't have to bother with tapping or helicoil etc, which I was hoping not to anyway. Maybe not the perfect fix but like I said I think it should be fine, good enough. Thanks for all the advice/suggestions.
 
Reply
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: