gpb9900 Posted November 17, 2009 Share Posted November 17, 2009 So I successfully replaced a the left manifold gasket, effectively silencing an exhaust leak. However, in order to install the gasket, I had to undo both manifolds. As I loosened the second bolt on the right-side manifold, I noticed that the bolt pulled out about three rows of the female threads in the engine block, itself. They are essentially fused to the bolt. At least, I could not scrape them out. There was about 2 rows of clean thread at the tip of the bolt before the stripped block threads clogged things up. Needless to say, there is not enough thread to catch so currently the right manifold is sealing with only one bolt. My question is two-fold: 1) Am I correct in assuming that if I can buy a slightly longer bolt with the same thread pattern, there are more threads deeper in the engine block that the original bolt would not have originally caught, which a longer bolt will? 2) Does anyone know what thread size the manifold bolts are? Normally, I would simply use a thread size checker at my local NAPA, but there is not enough clean thread left to effectively catch anything. Thanks. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted November 17, 2009 Share Posted November 17, 2009 It should not be a bolt. They should be studs for the exact reason you just discovered. Heli-coil it or oversize it. If you Heli-Coil it's a 10mmx1.25. If you oversize it then go to 7/16x20. Whatever you do, buy studs or cut your own from all-thread. GD Quote Link to comment Share on other sites More sharing options...
ivantruckman Posted November 18, 2009 Share Posted November 18, 2009 if all else fails, there are two extra holes in the cylinder head at 90 degrees from the older ones , if you have the resources to cut your flanges and rotate them 90 degrees, annd reweld them. the dang 12mmx125 helicoil kits are around 50 bucks , much cheaper to rotate the flange than buy a kit. unless you have to pay an exhaust shop to do it Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted November 18, 2009 Share Posted November 18, 2009 If you are talking cost, then it's by far cheaper to just oversize them to 7/16". But if you work on Subaru's in any quantity or very often then you should have the heli-coils on hand for 6, 8, and 10 anyway. Thread repair kits are also MUCH cheaper online. GD Quote Link to comment Share on other sites More sharing options...
gpb9900 Posted November 18, 2009 Author Share Posted November 18, 2009 It should not be a bolt. They should be studs for the exact reason you just discovered. Precisely what my father said when I showed him. Quote Link to comment Share on other sites More sharing options...
moosens Posted November 18, 2009 Share Posted November 18, 2009 Time-serts are awsome for this application. A little more $ than a heli-coil but you can then take the stud out again and again if you need to. m12 x 1.25 I think ..... been a while. Quote Link to comment Share on other sites More sharing options...
Frank B Posted November 18, 2009 Share Posted November 18, 2009 I couldn't find the 1.25 pitch bolts or studs when I did mine, had to use 1.5 helicoil and studs. Find the studs first so you don't buy the wrong helicoil set. They are too expensive to get it wrong. Some people have used a size slightly larger with thread cutting bolt. Fine if the car is junk or you intend on fixing it right later. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted November 18, 2009 Share Posted November 18, 2009 Why is it such a problem to oversize them to 7/16"? Just because it's not metric? Seriously - it's a cheap, reliable, and permanent solution to the problem. And if you ever wanted to go back to the correct size then you just heli-coil it. The 7/16" tap threads right in without drilling. I don't see a reason it should be relegated to "junk cars" or a temporary fix. Measurements are measurments. Standard or Metric - doesn't really make that much difference to me. Hell - if you go buy metric nuts for the OEM studs they will often be 17mm instead of the stock 14mm. Same goes for 8mm threads - stock is a 12mm nut but most that you can actually buy are 13mm. Whatever - find the right wrench and go to town. GD Quote Link to comment Share on other sites More sharing options...
Quidam Posted November 18, 2009 Share Posted November 18, 2009 (edited) Hey, Here is a 10 X 1.25 TIME-SERT kit, enough inserts to do two heads on an EA-82. It's $84.99 delivered. http://cgi.ebay.com/NEW-TIME-SERT-M10-X-1-25-Metric-Thread-Repair-Kit_W0QQitemZ300334541262QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item45ed5569ce I noticed that these inserts are the exact depth needed...the longest you should go anyway. Link just to save time for someone, in case they're wondering about these. I get exhaust studs a dozen at a time from a local muffler shop and they have on-hand any size I'd need for about a buck ea...RockAuto has genuine subaru for about 4 or 5 $ ea. Doug Edited November 18, 2009 by Quidam Text. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted November 18, 2009 Share Posted November 18, 2009 Time-Serts are nice, but frankly they are overkill for this application. I've never seen one fail that had been heli-coil'd and the heli-coil kits can be had with 10 inserts for half that price. I'm all about a better quality product if it's needed to do the job right or makes it easier..... but there's no reason to go all NASA on this one. Nice find on ebay though - I'll have to look into stocking those in my garage. There are times..... GD Quote Link to comment Share on other sites More sharing options...
torxxx Posted November 18, 2009 Share Posted November 18, 2009 if its EA82, take the manifold off, pull all the studs out, spin the flanges on the headers 90 degrees, install new studs into the the unused holes and ur done. weld up the pipe nad away you go. no more problems. I do this before I ever take out a tap or a "hell" coil kit Quote Link to comment Share on other sites More sharing options...
Frank B Posted November 18, 2009 Share Posted November 18, 2009 Why is it such a problem to oversize them to 7/16"? Just because it's not metric? Seriously - it's a cheap, reliable, and permanent solution to the problem. And if you ever wanted to go back to the correct size then you just heli-coil it. The 7/16" tap threads right in without drilling. I don't see a reason it should be relegated to "junk cars" or a temporary fix. Measurements are measurments. Standard or Metric - doesn't really make that much difference to me. Hell - if you go buy metric nuts for the OEM studs they will often be 17mm instead of the stock 14mm. Same goes for 8mm threads - stock is a 12mm nut but most that you can actually buy are 13mm. Whatever - find the right wrench and go to town. GD Yup, that's why I said go oversize now with a self threading(thread cutting bolt) to save some cash and just to get it going, then fix it later. I say "junk cars because if it where a jewel, you wouldn't do it that way. Every Subaru I've had would be considered junk , but I still did it the right way(metric helicoil. Don't drill thhe hole any deeper when you do it! The helicoils are stainless steel, so you won't have to worry about them rusting up. Use a steel stud, and a brass nut, if you can find one the right size, if not go stainless. That way none of it will rust together so you can take it apart again. Quote Link to comment Share on other sites More sharing options...
torxxx Posted November 18, 2009 Share Posted November 18, 2009 lol my bad on my post. I thought I was in the old school section. lol Quote Link to comment Share on other sites More sharing options...
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