#1 Exhaust head bolt missing, need opinion - Pic included |
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#1 Exhaust head bolt missing, need opinion - Pic included |
Trevorg7 |
Feb 10 2007, 06:04 PM
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#1
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Senior Member Group: Members Posts: 1,242 Joined: 7-December 04 From: Highland Village, TX Member No.: 3,241 Region Association: Southwest Region |
So - I am under the car doing a valve adjustment this morning and notice something troubling. No sure why I never noticed before but one of the #1 exhaust head bolts is gone. I assume its been gone for as long as I've owned the car. The PO had the motor rebuilt within a year of selling the car to me so I guess it snapped then and the builder never said a word.
So my question is what is the risk of running the car like this? Keep in mind its must have 25k miles on it with the bolt missing. Should I park it and replace? Drive it? Use this as an opportunity to by a Raby kit with new heads? Let me know. T Attached image(s) |
Aaron Cox |
Feb 10 2007, 06:09 PM
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#2
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Professional Lawn Dart Group: Retired Admin Posts: 24,541 Joined: 1-February 03 From: OC Member No.: 219 Region Association: Southern California |
you need an exhaust stud.....
otherwise i guarantee you have an exhaust leak |
Trevorg7 |
Feb 10 2007, 06:12 PM
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#3
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Senior Member Group: Members Posts: 1,242 Joined: 7-December 04 From: Highland Village, TX Member No.: 3,241 Region Association: Southwest Region |
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jimkelly |
Feb 10 2007, 06:29 PM
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#4
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Delaware USA Group: Members Posts: 4,969 Joined: 5-August 04 From: Delaware, USA Member No.: 2,460 Region Association: MidAtlantic Region |
remove heat exchanger and drill/tap for a helicoil ???
jim |
Dave_Darling |
Feb 10 2007, 07:31 PM
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#5
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914 Idiot Group: Members Posts: 15,051 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
You may have lost that recently. If really was gone 25K miles ago, the head is history--not even worth considering saving. Exhaust gases, when they leak like that, will erode the aluminum head--seriously erode it, and probably the top of the heat exchanger and the gaskets too! But by that point, the leak would have been really LOUD and the engine would be running really oddly...
Pull the exhaust and inspect. If there isn't any erosion (yet!) count your blessings and get a new stud in there. Which will likely involve a helicoil or time-sert or similar thread repair technique, but that's less spendy than buying a new (or new used) head! --DD |
Trevorg7 |
Aug 3 2007, 12:31 AM
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#6
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Senior Member Group: Members Posts: 1,242 Joined: 7-December 04 From: Highland Village, TX Member No.: 3,241 Region Association: Southwest Region |
Okay - I am finally going to get around to replacing this stud. Additionally I am going to replace the fuel lines and speedo cable.
The main question I have is the stud replacement. If I helicoil do I need to put in an OEM stud (8x53 for a 1.7) or would I use something else? I've never used a helicoil so I am just not sure. Thanks T |
DanT |
Aug 3 2007, 12:37 AM
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#7
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Going back to the Dark Side! Group: Members Posts: 4,300 Joined: 4-October 04 From: Auburn, CA Member No.: 2,880 Region Association: None |
Trevor, have you been able to inspect to see if the stud is broken off or just completely backed out. If it is completely backed out you can just replace it with a stock sized exhaust stud and nut.
Might not be as bad as you think. (IMG:style_emoticons/default/smile.gif) |
Trevorg7 |
Aug 3 2007, 12:41 AM
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#8
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Senior Member Group: Members Posts: 1,242 Joined: 7-December 04 From: Highland Village, TX Member No.: 3,241 Region Association: Southwest Region |
Trevor, have you been able to inspect to see if the stud is broken off or just completely backed out. If it is completely backed out you can just replace it with a stock sized exhaust stud and nut. Might not be as bad as you think. (IMG:style_emoticons/default/smile.gif) Hi Dan, Thanks for the note. I believe it is broken. Either way, I assume I'll need to order a stud from Pelican (or other). Does that sound right? Do you have a 1.7 stud laying around? T |
DanT |
Aug 3 2007, 12:52 AM
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#9
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Going back to the Dark Side! Group: Members Posts: 4,300 Joined: 4-October 04 From: Auburn, CA Member No.: 2,880 Region Association: None |
No, but I know who probably has one...local.
if it is broken you may be able to use and easy out and replace it with stock component. get under there and get the exhaust off and see what you have then you know what you need to do. Hope it is better than you think. |
Trevorg7 |
Aug 3 2007, 10:00 AM
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#10
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Senior Member Group: Members Posts: 1,242 Joined: 7-December 04 From: Highland Village, TX Member No.: 3,241 Region Association: Southwest Region |
Sounds good Dan. I'll have it off today or by the latest tomorrow and I'll let you know.
thanks T |
jasons |
Aug 3 2007, 10:12 AM
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#11
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Jackstand Extraordinaire Group: Members Posts: 2,010 Joined: 19-August 04 From: Scottsdale, AZ Member No.: 2,573 Region Association: None |
if it is broken you may be able to use and easy out and replace it with stock component. Be gentle with the easy out. I broke an easy out in an exhaust stud trying to do the same job. I ended up dropping the motor and pulling the head to fix the whole enchilada. Honestly, I don't know if there is any good way to get those out, with the motor in the car. I would say hit them with some PB Blaster, but it won't soak down anyway. You can try to get it good and hot before the easy out. I think I would probably get some good drill bits, and drill the stud out. Start small and work your way up. |
Trevorg7 |
Aug 30 2007, 08:26 PM
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#12
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Senior Member Group: Members Posts: 1,242 Joined: 7-December 04 From: Highland Village, TX Member No.: 3,241 Region Association: Southwest Region |
Okay, I finally got around to pulling this thing off and here is what it looks like. The threads appear to be stripped and there is no evidence of a bolt.
What are the options? Heilcoil? If so, any recommendation for sizing etc. let me know what you all think. Thanks T Attached image(s) |
type47 |
Aug 31 2007, 09:14 AM
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#13
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Viermeister Group: Members Posts: 4,254 Joined: 7-August 03 From: Vienna, VA Member No.: 994 Region Association: MidAtlantic Region |
timecert?
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rhodyguy |
Aug 31 2007, 10:01 AM
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#14
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,192 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
the other stud in the picture looks to have seen better days too. time to break out the Aerokroil and 12 or 13mm 1/4" drive sockets. take your time and try not to force the remaining fasteners. good luck.
k |
Trevorg7 |
Aug 31 2007, 10:10 AM
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#15
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Senior Member Group: Members Posts: 1,242 Joined: 7-December 04 From: Highland Village, TX Member No.: 3,241 Region Association: Southwest Region |
the other stud in the picture looks to have seen better days too. time to break out the Aerokroil and 12 or 13mm 1/4" drive sockets. take your time and try not to force the remaining fasteners. good luck. k Thanks for the feedback. you're right, in the picture the other stud looks bad or at least stripped. I just crawled under there and it actually looks good. Threads are fine. Are you seeing anything else that I may have missed? T |
rhodyguy |
Aug 31 2007, 10:14 AM
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#16
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,192 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
i see the carbon at the exh port but no burn/hot jet marks. make sure the old copper gasket is out before you put things back together.
k |
sww914 |
Aug 31 2007, 12:42 PM
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#17
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Advanced Member Group: Members Posts: 2,439 Joined: 4-June 06 Member No.: 6,146 Region Association: None |
The VW shops sell "step studs". They are normal 8mm on one end and 9mm on the other. A 9mm tap will just thread into the stripped out hole left by the missing stud, so you tap the 9mm threads and just screw the step stud in.
Really simple solution. |
Trevorg7 |
Aug 31 2007, 01:32 PM
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#18
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Senior Member Group: Members Posts: 1,242 Joined: 7-December 04 From: Highland Village, TX Member No.: 3,241 Region Association: Southwest Region |
The VW shops sell "step studs". They are normal 8mm on one end and 9mm on the other. A 9mm tap will just thread into the stripped out hole left by the missing stud, so you tap the 9mm threads and just screw the step stud in. Really simple solution. I really like that idea. I'll take a look. Thanks! T |
Trevorg7 |
Sep 1 2007, 08:19 PM
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#19
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Senior Member Group: Members Posts: 1,242 Joined: 7-December 04 From: Highland Village, TX Member No.: 3,241 Region Association: Southwest Region |
So, when it was all said and done I bought a 9/8 step stud (some think that is the original size but who knows) and drilled and tapped the hole. The 9/8 stud went in fairly easily. Bolted it all up and ran it. There is still an exhaust leak so I need to figure out where it is coming from. Seems that i can feel it puffing under the HE connections so I guess the HE are not seated. I'll look into that tomorrow.
T |
Trevorg7 |
Sep 1 2007, 08:20 PM
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#20
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Senior Member Group: Members Posts: 1,242 Joined: 7-December 04 From: Highland Village, TX Member No.: 3,241 Region Association: Southwest Region |
forgot the required pic.
Attached image(s) |
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