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Engine Specific Info and Questions => IDI Engine => Topic started by: doonboggle on April 14, 2010, 01:34:03 pm

Title: More on the head bolt question
Post by: doonboggle on April 14, 2010, 01:34:03 pm
Regarding the thread I started at ... http://www.vwdiesel.net/forum/index.php?topic=25119.0 (http://www.vwdiesel.net/forum/index.php?topic=25119.0)
... I finally got my XZN socket kit, and have now removed #5 bolt.

So back to the main point of what it is ... 11 or 12mm  ... so that I can order the proper set of bolts.  In taking it out, the washer is 'partially' seated within the base of the mounting flange on the floor of the head as viewed from the top.  Don't know if that is important, but seem to recall something like that mentioned in the earlier thread, so thought would advise.

Here are images of the bolt, with a ruler alongside.
Hopefully those of you that are versed in this can advise which set to order.

(http://i35.photobucket.com/albums/d185/doonboggle/headbolt002.jpg)


(http://i35.photobucket.com/albums/d185/doonboggle/headbolt001.jpg)
Title: Re: More on the head bolt question
Post by: truckinwagen on April 14, 2010, 01:43:48 pm
looks to be an 11mm bolt to me.
Title: Re: More on the head bolt question
Post by: rabbitman on April 14, 2010, 02:11:11 pm
Just found this online:

Quote
Fits all VW engines, gas or diesel, w/11 mm head bolts. Fits all gas engines 75-92(except 16 valve, VR6, and 1.8T) and early 1.5 and 1.6 diesel engines 77-82.5. Bolt length from underside of head to end 4 3/16 inches.

Quote
All VW diesels with 12 mm head bolts 82.5-02 including 1.6, 1.9, and early and late TDI. These do not fit gas engines. Bolt length from underside of head to end 4 9/16 inches.

Should clear it up ;)
Title: Re: More on the head bolt question
Post by: Mark(The Miser)UK on April 14, 2010, 02:17:13 pm
The bolt excluding the head, is 4 1/2 + a bit inches, which is 115mm which is a 12mm bolt.... ;D
11mm bolts were 98mm allen head.

Interestingly, early gasser bolts were 11mm and 96mm long with star heads. Could some early engines have ended up with those gasser bolts by mistake, leading to the bolt issues of the past?

Moderator please conjoin these 2 threads about threads :o

Edit; 'Pipped by Rabbitman'
Title: Re: More on the head bolt question
Post by: theman53 on April 14, 2010, 03:08:39 pm
You measure a socket head bolt from under the head if that helps.

BTW what side of the drafting ruler are you using? It has been a long time and I don't know what I am looking at. ;D
Title: Re: More on the head bolt question
Post by: truckinwagen on April 14, 2010, 03:11:03 pm
the best way to tell is to go down to the hardware store and see if it will thread into a 12x1.5 nut.
Title: Re: More on the head bolt question
Post by: doonboggle on April 14, 2010, 03:53:34 pm
EXCELLENT call truck. 
Looks like I forgot to put on the thinking cap this morning.
My 'DUH' account is becoming way overdrawn.

12mm x 1.75 pitch.  1.50 was tried, but hung up about 1/3 of the way on the shaft.

THANKS !!

the best way to tell is to go down to the hardware store and see if it will thread into a 12x1.5 nut.
Title: Re: More on the head bolt question
Post by: truckinwagen on April 14, 2010, 04:16:09 pm
is it 12x1.75?

I cant remember.

I could look the tap I use to chase the block threads real quick...

-Owen
Title: Re: More on the head bolt question
Post by: truckinwagen on April 14, 2010, 04:21:13 pm
just looked, and your right 12x1.75

good to hear that you got it figured out!
Title: Re: More on the head bolt question
Post by: Turbinepowered on April 14, 2010, 08:02:12 pm
Wanna know something funny?

12mm head bolt thread is, if I'm not mistaken, the same as your lug bolt thread is the same as the CIS injector thread. :D
Title: Re: More on the head bolt question
Post by: Vincent Waldon on April 14, 2010, 08:26:24 pm
Wanna know something funny?

12mm head bolt thread is, if I'm not mistaken, the same as your lug bolt thread is the same as the CIS injector thread. :D

is the same as the engine/tranny bolts... perfect use for old head bolts is for bolting engines to an engine stand...lots of threads so you can space the engine back far enough to work on the clutch.  ;)
Title: Re: More on the head bolt question
Post by: Mark(The Miser)UK on April 15, 2010, 01:45:29 am
Yep there are 14.25 threads per inch in the picture so M12 x1.75
Title: Re: More on the head bolt question
Post by: Rabbit on Roids on April 15, 2010, 10:06:16 am
Wanna know something funny?

12mm head bolt thread is, if I'm not mistaken, the same as your lug bolt thread is the same as the CIS injector thread. :D

lug nuts/bolts and injector heads are 12x1.5, so they must be different from head bolts..