NAXJA Forums -::- North American XJ Association  

Go Back   NAXJA Forums -::- North American XJ Association > NAXJA's Technical Forums > OEM Tech Discussion
Register FAQ Users List Calendar Mark Forums Read
HOME Member FAQ Sponsor Info Rules Donate Bylaws Store Members Chat E-Mail

OEM Tech Discussion Forum for OEM (Original Equipment) or stock XJs and MJs.

Reply
 
Thread Tools Display Modes
  #1  
Old January 22nd, 2009, 13:55
CBB311's Avatar
CBB311 CBB311 is offline
NAXJA Forum User
 
Join Date: Apr 2008
Location: Lawrence, Kansas
Posts: 24
thermostat housing help!!

i have an 89 4.0 and i went to change my thermostat today and got the bottom bolt off fine and snapped the top bolt on the thermostat housing. theres still about a half inch worth of bolt sticking out but its not moving. i doused it in PBlaster and went at it with some vice grips, nothing. i have a screw extractor set but i dont have room for a drill without dropping the radiator and fans, condenser, etc. any ideas? i have to work early in the morning and i need to get this done today. thanks
Reply With Quote
  #2  
Old January 22nd, 2009, 14:05
winterbeater's Avatar
winterbeater winterbeater is offline
NAXJA Forum User
 
Join Date: Jul 2008
Location: Royal Oak, Michigan
Posts: 5,315
Re: thermostat housing help!!

Can you heat the housing around the bolt with a torch?
Reply With Quote
  #3  
Old January 22nd, 2009, 14:28
joe_peters joe_peters is offline
NAXJA Forum User
 
Join Date: Apr 2008
Location: Grants Pass, OryGun
Posts: 13,750
Re: thermostat housing help!!

I think what you might need is a stud remover rather than an easy out. If you can't get your hands on a stud remover then heat is your next best bet. Either way you may loose the threads and have to use an insert.

If you have access to a propane torch you could warm the engine, then spray more penetrating oil, wait a bit, and repeat. I believe the term is convection, but the idea is as the parts cool the penetrating oil will be drawn into the threads. Please be careful of fire. Warming the engine and not the bolt slightly then spray.
Reply With Quote
  #4  
Old January 22nd, 2009, 14:38
5-90's Avatar
5-90 5-90 is offline
NAXJA Forum User
 
Join Date: Mar 2003
Location: Hammerspace
Posts: 18,799
Re: thermostat housing help!!

You broke the head off of the screw? Then slip the housing off.

Once you've done that, get a block of paraffin wax and a small torch. Heat the shank of the screw only until it's a dull red, then remove the torch and touch the paraffin wax to the junction between the screw and the head. Let it melt into the threads.

Let the screw cool (5-10 minutes) and you should be able to back it out. The screw expands to force the threads in the head open, then the paraffin "wicks" into the space that is made.

Replace both screws - preferred materials are brass/bronze, stainless, or SAE grade 5 coated with PTFE or RTV/silicone (in that order.) If all you can get are SAE carbon steel screws, replace them every time you take them out (it's cheap insurance.)
Reply With Quote
  #5  
Old January 22nd, 2009, 15:04
CBB311's Avatar
CBB311 CBB311 is offline
NAXJA Forum User
 
Join Date: Apr 2008
Location: Lawrence, Kansas
Posts: 24
Re: thermostat housing help!!

i dropped my radiator to have room for the drill, stripped an ez out in the process of trying to get the bolt out. tried heating it up, nothing. now i still have a round nub of whats left of a bolt stuck in my motor. im running out of daylight and ideas
Reply With Quote
  #6  
Old January 22nd, 2009, 17:15
CharlesS's Avatar
CharlesS CharlesS is offline
NAXJA Forum User
 
Join Date: Mar 2003
Location: Carmel Mountain Ranch, CA
Posts: 2,436
Re: thermostat housing help!!

If you have access to a welder... you might consider placing a nut over what is left of the bolt; weld the nut to the stub and then attempt to twist out the remainder of the bolt.
Reply With Quote
  #7  
Old January 22nd, 2009, 19:07
CBB311's Avatar
CBB311 CBB311 is offline
NAXJA Forum User
 
Join Date: Apr 2008
Location: Lawrence, Kansas
Posts: 24
Re: thermostat housing help!!

soo...i drilled the hole out to 5/16, started tapping the hole, got about a half inch deep and SNAPPED THE TAP! i swear this thing is either my best friend or my sworn enemy. any ideas?
Reply With Quote
  #8  
Old January 22nd, 2009, 19:13
bigdaddyjlove bigdaddyjlove is offline
NAXJA Forum User
 
Join Date: Jul 2006
Location: Atalanta
Posts: 483
Re: thermostat housing help!!

forget cutting the tap. Those things are hard as hell. Try a left handed drill bit? once a tap starts to back out it will usually come easy.

Good luck
Reply With Quote
  #9  
Old January 22nd, 2009, 19:22
5-90's Avatar
5-90 5-90 is offline
NAXJA Forum User
 
Join Date: Mar 2003
Location: Hammerspace
Posts: 18,799
Re: thermostat housing help!!

Quote:
Originally Posted by CBB311 View Post
soo...i drilled the hole out to 5/16, started tapping the hole, got about a half inch deep and SNAPPED THE TAP! i swear this thing is either my best friend or my sworn enemy. any ideas?
Wilton makes tap extractors - they have fingers that slip into the flutes on the tap and grip it, and you back it out that way. No telling how many times they've saved my arse...
Reply With Quote
  #10  
Old January 22nd, 2009, 21:13
CBB311's Avatar
CBB311 CBB311 is offline
NAXJA Forum User
 
Join Date: Apr 2008
Location: Lawrence, Kansas
Posts: 24
Re: thermostat housing help!!

does napa carry them? or any vendors you know of? im trying to get this thing back on the road tommorow im tired of the 12 hour thermostat change haha
Reply With Quote
  #11  
Old January 22nd, 2009, 21:18
5-90's Avatar
5-90 5-90 is offline
NAXJA Forum User
 
Join Date: Mar 2003
Location: Hammerspace
Posts: 18,799
Re: thermostat housing help!!

Quote:
Originally Posted by CBB311 View Post
does napa carry them? or any vendors you know of? im trying to get this thing back on the road tommorow im tired of the 12 hour thermostat change haha
Probably too late in the day - usually an MRO house will have them on hand. They're kind of a specialty item.

Failing that, the heat/wax and a left-handed drill bit will probably help. Just try to not heat the cylinder head around the broken tap overmuch - the idea is to expand the tap and wreck the temper of the thing, not melt a hole in the head.

Worst comes to worst, you can overdrill to 5/16" and use a 3/8"-16 tap (ream out the hole in the housing to 3/8" or so as well) and use a 3/8" screw - probably the easiest option you'd have. Just don't break another damned tap! You already know how much of a headache they are to get out once they're broken, don't you?
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
stock thermostat housing, 00 4.0L HO tcharon For Sale: Private Party Only. XJ ITEMS ONLY 0 October 16th, 2008 14:38
WTB thermostat housing Israel InterMountain Chapter For Sale/Wanted 3 September 9th, 2008 04:51
thermostat housing 4.0L dude in an xj For Sale: Private Party Only. XJ ITEMS ONLY 0 May 30th, 2007 17:24
Fun with the thermostat housing BIGSLVRXJ OEM Tech Discussion 0 January 29th, 2006 18:51
Aftermarket thermostat housing? Joe R. Modified Tech Discussion 4 August 9th, 2004 15:44


All times are GMT -7. The time now is 21:48.


Powered by vBulletin® Version 3.8.3
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
NAXJA and NAXJA logo's Copyright NAXJA. All content/images Copyright NAXJA 1999-2014