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Any new ideas for the old intake manifold stuck bolt problem?


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 93 Loyale EA82 SPFI

Whilst replacing my water pump etc. I discovered another problem - the right side (by alternator) intake manifold is leaking coolant, which I suspected for a few years.. and the back long bolt is stuck / frozen - and so are the 2 long ones on the passenger/left side also...  I soaked their heads and around the gasket (where we need really need it but probably can't get past the gasket) with liquid wrench and have to take care of other business so it will be a month before I can get back to it.  Read through lots of good ideas for stuck bolts BUT these long intake manifold bolts have the head of the bolt more than an inch and a half from the stuck threads going into the head so I don't think many of those ideas will work. I'm thinking a 6 point impact socket, impact wrench and maybe first drilling a small hole into the manifold close to the base of the bolt, about a quarter inch above the head that I can load up with some fancy "nut buster" sauce, I have liquid wrench from 20 years ago but maybe their is something a lot better now?

Here's some good ones

https://www.ultimatesubaru.org/forum/topic/44039-what-are-my-options-with-this-stuck-bolt/#comment-354824

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I’ve gotten some nasty EA intake manifold ones out like this. But it takes forever. 

Turn the bolt back and forth over and over and over again.  Not to remove jt - Just a few degrees. Just enough to work some of the corrosion loose without yielding of the metal.  After a few minutes take a break (do one of the other bolts).
 

Working it back and forth creates heat which increases the metals ability to deform and lead to shearing of the bolt.  you want to give it plenty of time to cool down. 

Keep repeating that step until you increase range of motion.  Once the head of the bolt comes up enough spray a high grade penetrant down the hole.  I have YIELD.

wash rinse repeat all of the above. 
 

If all the bolts are out but one is drilled or sheared off the head can still be stuck on all the packed corrosion in the bottom half of that hole that goes through the intake manifold.  The sheared/drilled bolt and corrosion are packed tight in the head and will hold it in place. 

if it’s one bolt only you can try to rotate the entire head back and forth to loosen the one stuck area, while prying upward.  If it’s more than one good luck, that’s not easy to drill or pry out if they’re full of corrosion. 
 

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  • 4 weeks later...

Just like @idosubaru says;

Turn the bolt a little bit, spray the bolt head with PB Blaster or other penetrant fluid.

Then torch the area of the head where the bolt is stuck with a map gas torch (handheld)

Turn the bolt back and forth just a couple degrees again.

Torch the area, spray with PB Blaster or dab on some candle wax while it's still hot. It will make the lubricant soak down to where it's needed.

Keep repeating the process until the bolt frees up

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  • 2 months later...

I was gone for about 2 months and I finally got back to working on this car and ended up drilling a small hole on the outside corner of the manifold where the bolt goes down to try to get penetrating fluid or blaster down in there and then went and got myself a modern 225 foot pound max rigid torque wrench gun and I haven't broke any of the  3 bolts loose yet, so I guess I gotta go get me M.A.P. Torch, thanks for the good suggestions.

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Edited by Craigar
had image in wrong album
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Well I didn't even think about a rethread kit but you say that making me think it's inevitable so when and if I gracefully get these bolts out it'll probably need to be rethreaded with maybe some bigger threads or you got to put in like a helicoil and for heating it up with a torch should I use a map torch or a propane torch, any preferences?

Thanks

Edited by Craigar
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Geez, I’m a backyard hack myself so I would go to my trusty but sometimes dangerous propane torch. I’m without a proper garage so my equipment range isn’t quite where I’d like it to be. But guys like us we always get by. 
 

Just be careful. Stay out of the newspapers my dad always told me. 
 

Those are super notorious. You’ll be working then for a long time and I’d still bet money you’re going to snap at least one bolt. 
 

Given the events up to now I’d say you’ve got a slim chance of being 100% successful. 
 

There are various manufacturers but TimeSerts are one brand where you drill, tap, and send in a threaded cylinder then stake it so it won’t back out. Then you can easily remove your bolts going forward for repairs in the future. Heli-coil is fine but won’t generally survive a removal. 
 

Yeah man, good luck on those bolts. 

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.. and about a week ago I sprayed em with my 20 year spray can of Liquid Wrench, - which I discovered 3 days ago had lost all it's pressure probably cause I unknowingly banged the head on it, probably shutting the hood.. So I bought a new spray can of B'laster and sprayed and soaked it a few more days - no cigar

th?id=OIP.MSIwHqQu47R_K5GI6MFFrAAAAA%26p

 

So here's the specs of a very nice portable 3/8" torque wrench I just bought from Home Depot on  sale for $140 with battery and charger

  • Lightweight Design. Heavyweight Performance.
  • Pair with MAX Output batteries for maximum power
  • Industry’s most compact
  • Powerful Brushless Motor delivers 250 ft./lbs. of breakaway torque
  • 3 speeds + auto-tightening mode provides adjustable power and speed
  • Auto-tightening auto-stops when fastening to prevent over tightening bolts
  • Auto-tightening in reverse, delivers full breakaway torque, then stops when the bolt is loose
  • Tri-Beam LED enhances visibility and provides even distribution of light
  • Compatible with RIDGID’s AC13B04N Impact Wrench protective boot (sold separately)
  • 100% Compatible: Works with all RIDGID 18V Batteries, Tools, and Chargers
  • Lifetime Service Agreement with registration within 90 days
  • Includes: R872071 18V SubCompact Brushless 4-Mode 3/8 in. Impact Wrench, R87002 2.0 Ah battery, charger, belt hook with screw, and tool bag
  • RIDGID: Build for a Lifetime

18V SubCompact Brushless Cordless 3/8 in. Impact Wrench Kit with 2.0 Ah Battery, Charger, and Bag

th?id=OIP.iUx7lJFRpgTnfGUfRYcHCwAAAA%26p

and it didn't seem to move any of em at full torque, even trying in both directions..

 

 So I cleaned the oil + road dirt mix off the passenger side intake manifold area (to lessen the chance of a bon fire) and only M.A.P. torched it for about 3 minutes total cause I've never done it before and was getting smoke and embers and nervous and cold and it was now dark outside where I'm working on it and the crappy harbor freight "free head lamp" was turning off all on it's own way to much - even after messing with it a lot.... and "amazing to me " got the bolt loose closest to the windshield loose! BUT it didn't want to go "looser" and "tighter" back and forth  (  CCW and CW ) only looser so went about 2 turns and going to give it chance to soak more over night. - and the head wasn't really very hot, maybe 110 F.

Progress, not perfection ... One down, two to go   Grrrr  ,, I mean "patience..." :mad:

 

 

Edited by Craigar
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Got em all out without breaking any :banana:- I don't think Ive stripped the holes either but haven't cleaned it up yet.  For this really tough bolt I decided to use a "paint stripper" heat gun on high for about 15 minutes and it still wouldn't budge so drilled a 2nd hole down closer to the threads, earlier had drilled a  hole about in the middle of the column to get the penetrating oil down into the crud in the bottom inch of the column also. After drilling this second hole and then using a lot of penetrating oil, then heat, I had progress

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had to heat up down by the head for at least 10 minutes with paint stripper heat gun, that's why my aluminum shield has turned golden brown .. I tried a M.A.P. torch but it was to scary and causing way to much smoke for my comfort.. and wiggled back and forth tell I could get about 1/4 turn, came back next day tried it cold no t so much movement so heated it up again and kept working it back and forth - but not going as far in as out.. then add more sauce.. do it again and eventually..

 

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Here's the bolt right after I got it out - I used a lot of B'laster penetration oil, and couldn't get it moving with the 3/8" impact gun - had to really push and pull on this ratchet - really hoping the bolt wouldn't break,, kind of amazed it didn't

large.20241217_181721crop.jpg.591b661966fe669adbfa756f4797e55b.jpg

 

 

 

Edited by Craigar
more bloody details..
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I bow to you sir ! Congratulations. 
 

Thread chasers ? Due to clean up the bolts? Or find fresh ones.

 

If find yourself getting fussy here in CT we’ve got this killer little place called the Nutty Company. And you’ll get pretty much what you need there. 
 

Not that you necessarily need these but I’d check your exhaust studs too. And if you care to the Nutty Co. has threaded rod in that size. I picked up a length and have taken a few cuts from it for various exhaust studs from 1600s to 2.2 and maybe the 2.5 too. 
 

Just a little info. Good luck. 

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Thank you! The bolts didn't break probably cause they're hardened or tempered, they have a #7 on the top of the bolts. Yea first I'm going to hit the bolts and threads with a wire wheel but probably use a die on this particularly bad rusted one - the rest didn't look as bad - 3 of them came out easily. Will see

Started a new topic for doing the gaskets and hopefully getting it back together without putting some of the spaghetti back in the wrong holes..

https://www.ultimatesubaru.org/forum/topic/186408-ea82-replacing-manifold-gaskets

 

 

 

 

Edited by Craigar
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