block thread for coolant plug stripped... - SailNet Community
Reply
 
LinkBack Thread Tools
post #1 of 17 Old 12-11-2011 Thread Starter
Senior Member
 
Join Date: Sep 2006
Location: Scotland
Posts: 2,364
Thanks: 0
Thanked 11 Times in 11 Posts
Rep Power: 10
 
block thread for coolant plug stripped...

The thread at the bottom of the aft barrel in my MD 17C Volvo is stripped, and so the coolant plug (brand new) will not tighten into it even with the help of teflon tape.

The coolant plug is the part number 829592 on this link...

Volvo Penta MD17C Diesel Engine Parts and Spares

I think the thread is 1/8 BSPT, but I cannot be sure.

It still holds coolant pump pressure, but I am afraid that it may blow out and cause an overheat. It reallty did turn far too easily today when I was draining the coolant.

I may have to drill and re-tap for a different design plug (and I have access for that) but I wondered if I could use a locking compound or some form of adhesive in there, and hope for reliability. I have heard that "liquid metal" may work.

Thanks.

Rockter.

Last edited by Rockter; 12-11-2011 at 05:13 PM.
Rockter is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #2 of 17 Old 12-11-2011
Senior Member
 
Join Date: Sep 2010
Location: South Florida
Posts: 152
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 6
 
Send a message via Yahoo to landmineop
Have you considered Helicoil ?
landmineop is offline  
Quote Quick Reply Share with Facebook
post #3 of 17 Old 12-11-2011 Thread Starter
Senior Member
 
Join Date: Sep 2006
Location: Scotland
Posts: 2,364
Thanks: 0
Thanked 11 Times in 11 Posts
Rep Power: 10
 
Landmineop :

It's quite a small thread, and it's tapered. Would a heicoil work?
Rockter is offline  
Quote Quick Reply Share with Facebook
post #4 of 17 Old 12-11-2011
Senior Member
 
Join Date: Sep 2010
Location: South Florida
Posts: 152
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 6
 
Send a message via Yahoo to landmineop
You could go to their site www.helicoil.com.ag and use the "contact us" to see what they say. It's sure worth a shot. Helicoil inserts are worth their weight in gold at times. Easy to use and strong. I've never had any propblems but maybe I was just lucky. Drop them an email and find out. Only takes a couple of minutes. Good luck and let us know what they say.
landmineop is offline  
Quote Quick Reply Share with Facebook
post #5 of 17 Old 12-11-2011
Senior Member
 
dabnis's Avatar
 
Join Date: Jul 2007
Location: Truckee, CA
Posts: 8,833
Thanks: 2
Thanked 116 Times in 114 Posts
Rep Power: 9
 
JB weld, or similar, into the old hole, wait until about half cured and screw the plug in just snug. After fully cured tighten just a little more and then safety wire if there is room. Try to dry the hole before putting the JB Weld into it. Never tried this exact application but have used JB Weld and Marine Tex on other things, it is pretty durable stuff. Not much to lose by trying it, next step could be the Heli - Coil as mentioned above.

Dabnis
dabnis is offline  
Quote Quick Reply Share with Facebook
post #6 of 17 Old 12-12-2011
TQA
Bombay Explorer 44
 
TQA's Avatar
 
Join Date: Apr 2009
Posts: 3,050
Thanks: 0
Thanked 88 Times in 84 Posts
Rep Power: 7
 
Get it dry, clean with cellulose thinners, coat both hole and plug with JB weld and refit.

Let it dry for 48 hrs and refill.

Job Done.
TQA is offline  
Quote Quick Reply Share with Facebook
post #7 of 17 Old 12-12-2011
Senior Member
 
Join Date: Oct 2009
Location: Gloucester, MA
Posts: 586
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 7
 
The correct answer to this is to drill and tap for a larger plug provided that you won't hit anything in doing so. I don't have my copy of Machinery's Handbook with me right now but I would imagine that you would completely drill out the old threads by going to a 1/4 BSPT. You shouldn't have too much trouble looking this up.

If you do drill it out, be very careful not to leave any metal shavings in your cooling system.
klem is offline  
Quote Quick Reply Share with Facebook
post #8 of 17 Old 12-12-2011
Member
 
Join Date: Dec 2010
Posts: 61
Thanks: 0
Thanked 1 Time in 1 Post
Rep Power: 6
 
Klem is correct. 1/4"x1/8" BSP reducing bushes are easy to get.
Grease up the tap which should keep most of the thread shavings out of the block. Afterwards clean the area thoroughly.

Stanley,
Marine Diesel Engine Vendor
NCboatrx is offline  
Quote Quick Reply Share with Facebook
post #9 of 17 Old 12-12-2011
Senior Member
 
dabnis's Avatar
 
Join Date: Jul 2007
Location: Truckee, CA
Posts: 8,833
Thanks: 2
Thanked 116 Times in 114 Posts
Rep Power: 9
 
Quote:
Originally Posted by NCboatrx View Post
Klem is correct. 1/4"x1/8" BSP reducing bushes are easy to get.
Grease up the tap which should keep most of the thread shavings out of the block. Afterwards clean the area thoroughly.
"most of the thread shavings"? The rest may end up going through the pump impeller? Hard to say what, if any, damage they might cause? JB Weld, as mentioned earlier, is tough stuff, maybe worth a try before drilling, if you can get a drill in there.

Dabnis
dabnis is offline  
Quote Quick Reply Share with Facebook
post #10 of 17 Old 12-12-2011
░░░░░░░░░░
 
hellosailor's Avatar
 
Join Date: Apr 2006
Posts: 11,807
Thanks: 6
Thanked 147 Times in 144 Posts
Rep Power: 11
   
Not being able to see this, but going by "drain plug" and "under"...

I'd also vote for JBWeld. Thoroughly clean and degrease a large area around the hole, and the threads, to make sure it binds well. But since you may want to unscrew a drain plug at some point in the future, I'd go a bit further.

Either drill and tap a new smaller drain plug in the middle of the existing one, or JBWeld a plate over the area around the hole, and (again) drill and tap a new drain plug fitting into the middle of the plate.

So either way, JBWeld, but providing for a new drain plug of some type before you seal it up.
hellosailor is offline  
Quote Quick Reply Share with Facebook
Reply

Quick Reply
Message:
Options

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now



In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.


User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
Stripped Transmission Dipstick night0wl Diesel 12 07-05-2011 08:14 AM
Possibly a stripped halyard? SiXeVeN Gear & Maintenance 9 06-13-2011 12:00 AM
Deck screws stripped. Kids4sail Gear & Maintenance 4 10-17-2010 05:27 PM
Banjo Bolt Stripped? T37Chef Gear & Maintenance 2 07-11-2008 01:03 AM
Stripped screw hole sklamar Gear & Maintenance 3 05-30-2002 07:10 PM

Posting Rules  
You may post new threads
You may 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 On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome