Exhaust manifold bolt sheared. Alternatives?

[TastesLikeChicken]

My trusty old '95 Nissan Kingcab has had a small tick for years. When I had some work done on it a year ago I asked the mechanic about it and he simply replied "Wouldn't worry about it. All dem ol' Nissans have engine ticks but they still run forever." So I didn't worry about it.

Recently the tick started getting louder and it would make a funny noise when I shifted. I began to suspect either a cracked exhuast manifold or a worn out gasket. Sure enough, while doing some inspecting this morning, I found a piece of the gasket that came right off.

To make a long story of removing the manifold short, the anti-seize bolt at the rear of the engine had sheared and looked like it had been that way for a long, long time. That's also right where the gasket went bad.

I'm not going to bother having the engine removed just to drill out one damn bolt. It sheared below the level of the engine block so I can't get a grip on anything to back it out. Anyone had any luck drilling out a bolt without removing the engine? Will it hurt to slap a new gasket in and replace the manifold and not worry about that one bolt since it worked fine for years in that conditions? Any other alternatives?

TIA for any helpful advice.

 

[BlackTigers]

do you have any room at all to get a drill to it? if so, drill out a hole and use a bolt extractor....that should work.

if not....thats going to be a tough son of a bitch to back out.

 

[IcePickFreak]

Try an ez-out? It's a gamble on how easy it would be being an exhaust manifold bolt, how bad were the others to turn out?

Short of that, it won't really hurt anything to just toss a new gasket on and leave the one, but it's still going to leak and that leak will burn out the gasket in that area again down the road.

 

[TastesLikeChicken]

I might have just enough room to get a small drill with a short bit in there. It's pretty tight though. Getting the bolt remnant properly center punched likely isn't going to be easy either.

The other manifold bolts weren't bad at all. Took most of them out with a small 1/4" ratchet, a deep-well socket, and a few bloody knuckles. The bitches were the hex nuts on the exhaust flange. Cracking those was a mofo.

Thanks for the advice gents. :thumbsup:

 

[BlackTigers]

thats what will be able to get it out for ya, if you can drill a hole. as you turn that in, itll turn the bolt out. thats going to be your best bet, id think.

 

[Howard]

I might have just enough room to get a small drill with a short bit in there. It's pretty tight though. Getting the bolt remnant properly center punched likely isn't going to be easy either.

The other manifold bolts weren't bad at all. Took most of them out with a small 1/4" ratchet, a deep-well socket, and a few bloody knuckles. The bitches were the hex nuts on the exhaust flange. Cracking those was a mofo.

Thanks for the advice gents. :thumbsup:

Buy an automatic center punch.

 

[skyking]

I've drilled and extracted several bolts and studs in aircraft, truck, and automotive engines. It is never easy but always doable.
You need a good center mark and have the skill to drill it out on center as much as possible. That means starting out on center and maintaining alignment. Right angle drill motors help in tight quarters. Drill the bolt all the way through to relieve it. Don't worry about drilling into the block, there is space behind the bolt that you will feel as you get through the bolt.
You need to relieve it because it is likely frozen in there with corrosion. Get some good penetrating oil in next and leave it overnight if you can.
The easy out pictured above will work.

 

[SooperDave]

If you decide to drill it a couple of things

1) Center punch. If you drill out of center you lose alot of your power and the more power you use the more likely you are to break the extractor.

2) Drill straight and go all the way thru. You can use the hole to spray in some penetrant and you don't want the extrctor to bottom.

3) If you want to drill a small hole first and see if it comes out easy fine. If it doesn't, don't mess with it. Drill to the largest size size you can within reason (see drill straight). You want to use a fluted extractor that will allow the fastner to collapse as it is turned. the thinner the wall the easier it collapses. The screw in style tends to expand out the walls, tightening it the farther in it goes. It gets a better bite but there is a cost. I've always had better luck with the fluted style for this reason. If you go with the screw in style stay with a smaller hole.


edit: I need to type faster. Skyking beat me to most of it

 

[alkemyst]

do you have any room at all to get a drill to it? if so, drill out a hole and use a bolt extractor....that should work.

if not....thats going to be a tough son of a bitch to back out.

make sure you do this with a reverse (left hand) drill bit. Sometimes it will back itself out.

Also if there is anyway to first remove the part to see if you can get hold of it without drilling that will be best.

The most common problem is if you are not dead on when you drill the extractor will usually sheer.

Use a center punch (which also giving a whack may free the bolt more too)...

If you mess it up it's usually best to retap one size larger even if you have to use a metric bolt than a helicoil.

 

[alkemyst]

If you decide to drill it a couple of things

1) Center punch. If you drill out of center you lose alot of your power and the more power you use the more likely you are to break the extractor.

2) Drill straight and go all the way thru. You can use the hole to spray in some penetrant and you don't want the extrctor to bottom.

3) If you want to drill a small hole first and see if it comes out easy fine. If it doesn't, don't mess with it. Drill to the largest size size you can within reason (see drill straight). You want to use a fluted extractor that will allow the fastner to collapse as it is turned. the thinner the wall the easier it collapses. The screw in style tends to expand out the walls, tightening it the farther in it goes. It gets a better bite but there is a cost. I've always had better luck with the fluted style for this reason. If you go with the screw in style stay with a smaller hole.


edit: I need to type faster. Skyking beat me to most of it

going all the way through could be an issue with water jackets.

 

[bruceb]

I agree, remove the manifold first. It will be a lot easier. Also put a stop mark or tape on your drill bit. You should not need to drill in more than 1/2 to 3/4 of an inch at most. Once you think the E-Z out can fit, it might be a good idea to heat the area around the bolt hole with a small torch, then use the E-Z out. This way it will help to loosen up all the rust and crude holding it in place. Another option, you have a very old car and motor. Consider pulling the head off and work on it that way. As a bonus, you get new head gaskets installed and perhaps a valve job done. End result, engine will run almost like new.

 

[BlackTigers]

pulling the head isnt a terrible idea. That's probably how I'd attack this.

if you drill in at an angle, theres a good chance that you'll break off the extractor inside the bolt, inside the head...which would end up being a nightmare for getting that bolt out period. Pulling the head would let you set the head on its side and drill straight down, so you can check the angles much easier and have a better shot at not snapping the bit off.

Hell, have it checked out and looked at too while its off. It'a an older car and probably would'nt hurt to have it looked at.

 

[skyking]

going all the way through could be an issue with water jackets.

It's never a problem really. I've done many of them. If it is a factory bolt it was designed with a proper amount of free blind hole behind the end of the bolt. Once you get through the bolt you'll know.
The big help of drilling it through is getting oil behind it, and relieving stress on what remains. I'll start a little small and give it a try after letting it soak. If that does not work I'll drill bigger. I've had a few never really give up to the easy out, but because I was dead on center I could drill it out and eventually peel out the remains and clean up the original threads with a tap.

 

[TastesLikeChicken]

I'm trying to avoid pulling the head. It's a V-6 so if I pulled one side and had it redone I would have to pull the other side as well. Then I have to deal with removing the a/c compressor, water pump, fuel injector components, timing belt, etc. Don't want to open that can-o-worms. Plus the truck is already 16 years old and it's not really worth putting that much work into it.

I've found some drill-out bolt extractor kits that I'm going to try. Along with a right-angle drill adapter it'll be worth giving it a shot. If it doesn't work, no big deal since it apparently has been without a bolt for years anyway. If I fail at extracting the bolt I'll just slap the manifold back on using the available bolt holes and be done with it.

Thanks for the help and info.

 

[5150MyU]

If the stud is close to flush another option is to tack(weld) a nut to the stud.

 

[alkemyst]

I'm trying to avoid pulling the head. It's a V-6 so if I pulled one side and had it redone I would have to pull the other side as well. Then I have to deal with removing the a/c compressor, water pump, fuel injector components, timing belt, etc. Don't want to open that can-o-worms. Plus the truck is already 16 years old and it's not really worth putting that much work into it.

I've found some drill-out bolt extractor kits that I'm going to try. Along with a right-angle drill adapter it'll be worth giving it a shot. If it doesn't work, no big deal since it apparently has been without a bolt for years anyway. If I fail at extracting the bolt I'll just slap the manifold back on using the available bolt holes and be done with it.

Thanks for the help and info.

Use the biggest extractor you can.

Get a left-handed bit and run your drill in reverse too. Make sure you centerpunch and drill slow.

being you snapped it off it was probably at least torqued down a bit there...without a bolt at all it's going to be a much worse tick. It will be perfect when you first install, but in a few hundred miles much louder as the gasket gets blown out.

 

[TastesLikeChicken]

Use the biggest extractor you can.

Get a left-handed bit and run your drill in reverse too. Make sure you centerpunch and drill slow.

being you snapped it off it was probably at least torqued down a bit there...without a bolt at all it's going to be a much worse tick. It will be perfect when you first install, but in a few hundred miles much louder as the gasket gets blown out.

That's the thing. I didn't snap it off. It was loose and came off with no effort. I don't know how it didn't simply fall out. The shear surface has a patina that indicates that it has been that way for a long, long time.

My two biggest challenges are going to be properly center punching it and aligning the bit so it goes straight into the bolt. Hopefully I can find a spring loaded center punch with a decent amount of pop to it to create the indentation. I can make a little wooden jig that will position the punch in the center so that shouldn't be a problem. Possibly I can make a drill guide out of some wood as well so it will maintain the bit at the correct angle.

 

[alkemyst]

It's never a problem really. I've done many of them. If it is a factory bolt it was designed with a proper amount of free blind hole behind the end of the bolt. Once you get through the bolt you'll know.
The big help of drilling it through is getting oil behind it, and relieving stress on what remains. I'll start a little small and give it a try after letting it soak. If that does not work I'll drill bigger. I've had a few never really give up to the easy out, but because I was dead on center I could drill it out and eventually peel out the remains and clean up the original threads with a tap.

The problem and I have experienced it is the bolt takes a lot of effort to get through...the hole in the back is a siliver or less...the head is soft iron or aluminum. By the time you know you are through it.

Sounds like the OP is going to have a challenge getting a hammer and tap in the situation.

In my 240SX, one exhaust stud snapped loosening it. I drilled crooked, thought I could do it without a center punch. Tried the extractor and of course it snapped. I soaked and sprayed it down first for 2 days.

Paid a shop....they just ground it out a bit and tried to JB Weld a stud in the hole...(found this out later).

I then just drilled it out and tried a helicoil. I hit the water jacket so the helicoil just leaked.

So I re-drilled and tapped it to 12mm. It's been dry for 3 years...and leak free. I used high-temp silicone and let it set over a three day weekend as without it it was dripping coolant.

 

[bruceb]

Sears has the automatic center punch. General Tools Model #79

http://www.sears.com/shc/s/p_10153_1...1&blockType=G1

Runs about $18

 

[skyking]

Alky I hear ya, glad you got it sealed up.
OP, get good lighting in there and see if you can position a large mirror. Take your time.