17 replies to this topic

[Glenn Davis]

I'm prepping the engine bay for an engine pull and I'd like to pull the exhaust manifold and downpipe as a unit prior to the engine.  The 22mm nut on the exhaust side is stuck hard.  Any ideas on loosening the nut?  I'd hang a pipe on the wrench, but I don't want to jack up the manifold outlet.

 

Any favorite methods?  Heat? Chemicals?

[Bench Racer]

Don't know the exact nut and position.    The nut spliter comes in different sizes.

 

5/8" Capacity Nut Splitter

[davew]

I have to assume you are not talking about a 1991 car, as they don't have egrs.

 

PB blaster is the best rusty bolt product I have found. You can do a search for some home made concoctions. And probably will need heat also. Just be careful, penetrating oil is flamable

 

Dave

[HoneyBadger - BrianW]

If you having problems with that nut, I would leave the manifold on the engine when you pull it. You will have a much easier time getting to the nut once the engine is on the stand.

[Glenn Davis]

 

Don't know the exact nut and position.    The nut spliter comes in different sizes.

 

5/8" Capacity Nut Splitter

 

Don't want to split the nut as then I'm guessing I need to buy a new pipe.  The nut looks like a compression nut that's permanently attached to the EGR pipe.

[Glenn Davis]

If you having problems with that nut, I would leave the manifold on the engine when you pull it. You will have a much easier time getting to the nut once the engine is on the stand.

That was my first thought, but getting the manifold off would give me more room.  That and I hate to lose to a nut.

[Glenn Davis]

I have to assume you are not talking about a 1991 car, as they don't have egrs.

 

PB blaster is the best rusty bolt product I have found. You can do a search for some home made concoctions. And probably will need heat also. Just be careful, penetrating oil is flamable

 

Dave

Probably try something like this tomorrow.  Thanks Dave.

[HoneyBadger - BrianW]

That was my first thought, but getting the manifold off would give me more room.  That and I hate to lose to a nut.

The manifold wont interfere with removing the engine.. well at least not enough to be a concern. I normally leave it on when removing and put it back on the engine before reinstallation. I do remove the coil pack and cam sensor... dont ask how many cam sensors I have broken, forgetting someone put it on before sticking the engine...

[Glenn Davis]

The manifold wont interfere with removing the engine.. well at least not enough to be a concern. I normally leave it on when removing and put it back on the engine before reinstallation. I do remove the coil pack and cam sensor... dont ask how many cam sensors I have broken, forgetting someone put it on before sticking the engine...

Thanks.  Coil packs are on the top on this one (2002).  Another PIA is getting to the O2 sensor with the steering shaft limiting wrench movement.  Leaving the manifold on would solve this problem as well...

[Marc Cefalo]

Heat plain and simple. The egr tube nut at the manifold ,if stubborn, must be heated before breaking loose. Take your time to make sure the whole nut is heated evenly. Use a high quality 22mm wrench to break it loose. Once loose by a quarter turn, work the nut back and forth a little further back and forth several times to make sure you don't marr the threads on the manifold.

If the o2 is being difficult, remove the down pipe with it separate from the motor. For the manifold outlet nuts, heat them as well. Be ready to strip and or break these as it's sometimes a 50/50 chance of success.

Once the manifold is separate from the motor and on a bench with a vise, you can them work out the rest of the remaining studs with a heat and vise grips or stud removal sockets. You may have to chase the threads m10 x 1.5 with a tap to clean them up before putting in new studs.

I have the correct metric double ended studs and nuts if you need to replace them.

[Glenn Davis]

Heat plain and simple. The egr tube nut at the manifold ,if stubborn, must be heated before breaking loose. Take your time to make sure the whole nut is heated evenly. Use a high quality 22mm wrench to break it loose. Once loose by a quarter turn, work the nut back and forth a little further back and forth several times to make sure you don't marr the threads on the manifold.

If the o2 is being difficult, remove the down pipe with it separate from the motor. For the manifold outlet nuts, heat them as well. Be ready to strip and or break these as it's sometimes a 50/50 chance of success.

Once the manifold is separate from the motor and on a bench with a vise, you can them work out the rest of the remaining studs with a heat and vise grips or stud removal sockets. You may have to chase the threads m10 x 1.5 with a tap to clean them up before putting in new studs.

I have the correct metric double ended studs and nuts if you need to replace them.

Thanks Marc.  I got the O2 sensor loose, but I can't get a wrench in to continue the progress.  I'll work on the EGR pipe tomorrow.

[RazerX]

You can remove exh manifold w/o removing that nut.  You need to remove the coil pack as noted above and take the nuts off the outlet studs on the manifold.  The tube is flexible enough to be coaxed over the outlet studs and around the back of the engine.  

 

If done gently is does not bend the tube and it mates fine with intake surface.  

[Brandon]

Another thought was if you're already under the car dealing with the O2 sensor (or feel like taking the downpipe off), I believe with a shorty 22mm open-end wrench will permit the EGR nut removal that way.

 

At least that's what I was observing while trying to use a full-size 22mm from above on my '96; wrench going under that driver's side frame horn, below the steering column.

Ended up 'tip-toeing' it with a pair of channel-locks...

PITA!

[Glenn Davis]

You can remove exh manifold w/o removing that nut.  You need to remove the coil pack as noted above and take the nuts off the outlet studs on the manifold.  The tube is flexible enough to be coaxed over the outlet studs and around the back of the engine.  

 

If done gently is does not bend the tube and it mates fine with intake surface.  

I took another try with some PB Blaster and got the nut to move, but it seized back up after a quarter turn, or so.  Going after the other side was my next thought.  I don't have any coil pack to worry about on the 2002, but I do still have the downpipe connected.  I'm thinking I may have enough room to get the EGR pipe up and over the motor with the downpipe still connected.  We'll see...

[Glenn Davis]

Another thought was if you're already under the car dealing with the O2 sensor (or feel like taking the downpipe off), I believe with a shorty 22mm open-end wrench will permit the EGR nut removal that way.

 

At least that's what I was observing while trying to use a full-size 22mm from above on my '96; wrench going under that driver's side frame horn, below the steering column.

Ended up 'tip-toeing' it with a pair of channel-locks...

PITA!

My initial thought is to get the O2 sensor once I move the manifold/downpipe enough to get clearance.  Alternatively, now that I have the harness mostly removed, I think I may be able to get the closed end of a 22mm gearwrench over the connector and down the cable to the sensor.  Or even just leave the sensor in until the whole unit is removed.

 

BTW, the next frozen fastener I ran into was the lower alternator bolt.  I know it doesn't yet need to come off, but it was just hanging there asking to be removed.  My dog learned some new words on Sunday...

[Keith Novak]

I don't know how much different the '02 configuration compared to my '95 but for what it's worth, I took an adjustable wrench and ground the handle down making it a stubby.  I kept trying it, and kept grinding until I had it stubby enough to be able to turn the nut adequately.  It took a while to customize the wrench but compared to all the difficulty I had getting it off prior to that, it's been more than worth the time spent.

[Cy Peake]

Use some copper anti-seize when re-installing that EGR tube nut into the exh manifold.  I haven't had an issue getting it loose since I did this.

[Glenn Davis]

Hopefully the engine builder will take care of it...