MTFCA Forum

Over the years I have read a lot of posts talking about exhaust nut wrenches. How important is it to have one?

In the 8 to 10 years I have had my T, I have never had an issue with this nut. The previous owner started a frame off restoration. Rebuilt the engine, had it back on the chassis and the exhaust hooked up. That is where he quit. He never started it up.

So am I lucky not to have an issue? Or is this a random tool people just like to have?

It's handy and has a nice angle to get away from the hogshead. You get a tight one it helps.
And they are one "people like to have".

Well, if you go to remove that nut after its been on there for a few years, you may give anything for one of those wrenches! Don't even think about a pipe wrench......they ruin things in short order.

You might consider the exhaust nut retainer sold by the vendors. It's a very simple and inexpensive gizmo that holds the nut firmly.

I purchased one of the special wrenches, "just in case" a few years back. When it came time to do a valve job, I discovered that the nut on the manifold was larger than the span of the wrench. Don't know how that came to be, but a pipe wrench worked fine for me.

There is nothing like having the right tool for the job, and the road to miserable is
most easily found when you don't have them. This one is inexpensive and invaluable
when you need it.

Funny that this question would come up. I am currently trying to remove a stuck
hub from an ancient toilet tank. The collared nut is 2.51", with a 3/16" tall hex face,
requiring a very special wrench that is very large AND thin. Local plumbing supply
houses had no such critter, so I bought a 5" circle drop of 1/8" plate and did some
cutting, welded on a handle and voila ! However ....

The last person to touch it, installed the nut upside down, so my nice, skinny box
end wrench cannot be dropped over the collar to work, and the 1/8" steel too weak
to cut it for use as an open end wrench. So, it looks like I get to go buy some 3/16"
stock, and start all over again !

Now, if the vendors would just carry such a critter .....

The folks who have them come loose and use the retaining rings are the ones who have not used the Ford wrench. They are available as a reproduction now if you are unable to find an original. They seem to be slightly more expensive at around $50-$60 in my experience.

Definitely a great tool to have in your collection. I bought one that i thought was was an original, but turned out to be a repop that like others have claimed, was too small for the nut. Not a big deal, but some massaging of the wrench was required for it to fit properly.

This is my exhaust nut wrench that I picked up this past summer at a garage sale $2.00 just an old wrench to that guy like gold to me. The other is for Raoul this is what I use for that type of nut on a toilet and under the sink on the basket nuts. Jim

On the exhaust nut wrench, you can get by with a big old fashioned monkey wrench. Not as good as the real thing, but . .. On the toilet nut, soak the nut with lacquer thinner. If the last guy used plumbers putty on the joint, that will loosen it up.

Jim - that plumber's wrench would be great IF the jaws were only 3/16" thick !
I have one like yours, and hunted all over town for a thin one. With the collar nut
installed with the collar away from the tank base, the regular wrench will not fit
in that narrow slot where the hex is.

Dan - we think alike. Been soaking now for a day and a half. The nut is zinc. The
hub is brass, the friction washer WAS steel. 100 years of urine salts have turned the
plumber's putty and washer into quite the bound-on mess. Heat would be the easy
fix, but I am unwilling to get a torch near that porcelain and fracture something made
of solid unobtainium. Best to have patience on this one.

I have tried a large pipe wrench on it, but these apply binding pressure on the hub
as they apply pressure to spin the nut off. A wrench that grips the hex will not, so
perhaps that will be enough to break it loose. We'll see tomorrow afternoon.

There is a reason that wrench has a short handle.

I added an 18 inch piece of pipe over the handle for extra leverage.

Then heated the nut area with a rosebud torch so the nut would turn.

That almost worked, but the whole end of the exhaust manifold turned easier and broke off.

If the nut turns too easy, it can loosen on a tour and the wrench is very handy to have along.

The little lock clamp that prevents the nut from coming loose is very good to have installed.

The Ford exhaust nut wrench is an essential tool. There are, as others have mentioned, other tools and tricks that may work in a pinch, but nothing does the job like the actual Ford z wrench. There are other Ford z tools that are also essential, but that is anothet topic for anothet time.

Those exhaust nuts can be tricky. Heat they bind, use a pipe wrench they bind, use the right wrench and you have a much better chance. Raoul, can you just cut the zink nut with a speedy wheel or rotary file and discard it? I would think you will be installing new any way.

The repro wrenches were never too small. One of the vendors was selling a cast-brass nut off and on over the last 40 years or so that was too big on the outside diameter. These nuts weren’t being made for quite a while, but showed up again a couple years ago. The threads also don’t go deep enough in these nuts to get the pipe leak-tight to the manifold. If your brass nut looks cast, it could be one of these. The “good ones” look like they are machined “all over”.

I'm surprised Ford didn't include them in their tool rolls! A year or two ago Bob Bergstadt made a run of beautiful pack nuts. They were not the proper size, and it wouldn't fit the wrench. I think he has the problem fixed now.

It's been noted that a number of exhaust pipes are not correctly formed. Whether the manifold pack nut stays cinched up tight often depends on how well the pipe is seated on the manifold, and whether gravity and vibration will work against its initial position.

I have a spanner much like the original T tool, but mine had its origins as an agricultural machinery tool. My weapon of choice for the packnut is an 18" Bahco shifter. It has the same angled head, will fit different sized nuts, and gives good leverage. On our RHD cars we have the added complication of having to work around the steering column.

Allan from down under.

Allan, any chance you could post a photo of that ? I seldom consider what advantages and problems the LHD cars present, but they fascinate me. I've never seen one in the flesh.

Don’t tell anyone, but when I recognized that the nearest swap meet to me was still an eight hour drive and then a crap shoot as to whether I’d even find the proper wrench for sale there, I went to the local cheap tool store to see what they had. What I ended up with was a 24” long adjustable wrench that so far has worked just fine. Maybe it worked because I had a brand new manifold, nut and exhaust pipe, but it worked. I also suspect my exhaust nut was one of the wrong size ones anyways so the Ford tool wouldn’t have done the job.

There was a guy a couple years back selling repros that he was cutting from very thick steel. I think he was using one of those water jet cutting tables.

I bought one and have used it. It works very nicely.

My son calls it the "Mother Of All Wrenches".

Rich, I am on holiday from posting photos!!!! When I get my new laptop, learn how to transfer photos from my phone to it, unlearn how to downsize them and learn how to post them again, this thread may be long forgotten.
Suffice to say that the shifter is angled back to allow it to pass below the steering column. A direct pull at right angles to the nut is not achievable. The wide jaws on the shifter still allow plenty of purchase on the nut.

Allan from down under.

Spanner ? Shifter ? Purchase ? What kind of Ingles you speaking there, Allan ?

John - the nice, heavy brass/bronze hub and fill assembly is a work of art and should
last 1000 years .... IF that nut would only break free !

So, I went and bought a 13" round of 3/16" steel and drew a wrench on it, cut the shape
from the big piece, and began tuning into an actual wrench (spanner)

A destroyed example mic'd out at 2.51", but the problem nut mic'd out at 2.58", so I
spent some additional time with a big file fine tuning the spread. Got it fitting nice,
braced the tank in a way to get good leverage, and the 11" handle just isn't enough to
bust it loose. It was 2200hrs by this time, so I gave the nut another soak of ATF and
lacquer thinner and left it to think about its behavior overnight. If the soaking doesn't
get it in the morning, I'll see what sort of handle material I have in the welding room
and add another foot of muscle.

Its nice had a correct tool
I have ised the plumbing tool pictures above but after ive broken a few i broke down and got one
There was a guy who had some made on a qate jet machine
Have a couple if times taken the manifold off with the pipe still on and taken apart out side the xar

I got one of those that is smaller than the exhaust nut, fortunately I discovered this before the need arose. I also had the misfortune to break down on the side of town known for shootings I had observed a couple of youngsters coming toward me so I picked up that wrench as I was getting out and they walked off in a different direction without a word being spoken.

What makes a correct pack nut wrench so nice to use is the angle of the handle. Go with a pipe wrench if you choose, but if you get a chance to use the correct tool, you won't go back to the pipe wrench! You can still find them on ebay for $30-40.

Some of the repo nuts are round not hex and the only wrench that will work is a pipe wrench.

ROUND???????????????????????? Where are those coming from ???

What good would a round pack nut do? Maybe someone is smoking a little too much dope, although a pipe wrench on that one would likely do the trick.

I have come across a couple of round ones in my time. Both were steel. One at least had knurling across the outside, and that knurling had suffered under a pipe wrench. I surmised they were for early cars without the flange, so a they did was contain the packing around the pipe. Am I wrong in this assumption?

Allan from down under.

They were probably rounded off from using a pipe wrench on them and chewing off the corners. Jim

As you pull on that wrench think about what's holding the manifold in place while you exert all that pressure.

I have owned this 26 for 60 years and the pack nut was round when I recovered it from the prairie in Saskatchewan.

Well David, that shoots down my theory that the round ones were for early cars, but it supports the existence of round nuts. Yours looks just like I remember the ones I have seen. Perhaps it's a Canadian thing.

Allan from down under.

The round nut would have greater strength than the hex nut because the flat portion on a hex nut is very thin and susceptible to cracking, whereas the round nut has uniform thickness all around. I believe I put that round nut on 60 years ago by hand and it has never leaked.

Interesting that round pack nut. Did a check of 1923 Canadian Parts and Price list, same part as USA, #3061, plus the illustration in the Canadian Parts book shows hex pack nut! So original is it, or not, interesting round pack nut, guess you hand tighten or use a round wrench

Just used my repro wrench last evening, put on a new exhaust pipe, and changed out the old hex pack nut, as the threads were worn. The new nut rides on old manifold with threads that are so-so. But the pack nut wrench, Ford design, pulled it snug and safe.



Off with the old pack nut, after a soak with spray Kroil penetrating oil.

Lined up new pack nut, new pipe, centering the flange. Muffler removed to allow the exhaust pipe to remain centered for the flared flange to stay on the manifold flange. Good amount of anti-seize on threads helps with on and later off of the pack nut.
Old pack nut had compromised threads so it really wasn't holding firm enough.
Now even with new pack nut, tight with Ford style wrench, the radiator clamp is a good prophylactic for inhibiting that dreaded loose exhaust pipe

p.s. Even if this radiator clamp is redundant, it may come in handy on tour for other in distress with fumes in the cockpit!

When I put the exhaust pipe and nut together, I apply a good amount of “muffler cement” to the threads and contact surfaces. Hardens and seals when heated and never comes loose or leaks.

I prefer the early style 3Z pack nut wrench that Dan posted above.

Since I no longer own any more T's, I recently advertised on MTFCA that I have a list of parts,tools etc available on request . One of the tools is a large and heavy wrench with the # 3Z-624 on it.The opening is 2 1/8" across. I no longer have any Original or Repro nuts to check if they would fit. Can anyone tell me which pack nuts would fit this wrench . I wouldn't want to sell it to someone if they can't use it. If anyone would like to see photos -just email me and I'll attach it to your email. I can also attach a list if you like. benlefebre@juno.com

I'm all for using the original or reproduction wrenches. However, here's how I solved the problem since those wrenches would be pretty sloppy on my exhaust nuts. I have two cars, and both have nuts with flats measuring between 2.025" and 2.050". Some may suggest they're reproduction nuts; they very well could be, but I know they're at least 45 years old. This adjustable wrench has a nice smooth action, feels good in the hand, goes from 0" to over 2.4", and is only 12" long. It also fits in the nut area on the cars just fine. Yes, it costs almost as much as a Z wrench, but it fits perfectly regardless of nut size or if the nut isn't consistent between its three sets of flats. Plus, you can use it for a lot of other purposes. Just my 2c, in case it could help someone else out. I was extremely pleasantly surprised by the quality. The packaging said it was made in Taiwan.

https://www.amazon.com/gp/product/B016O ... UTF8&psc=1

Same one made from slab of steel and posted in "February" but now painted.

I got a large Harbor Freight (24 inch) adjustable wrench with a 20% off coupon a few years ago.
It is tight but fully open it fits the exhaust nut.
If the nut is rusty I use a flat file to clean it up before using the wrench.