ROG100

Having just helped Sean and Danny remove a stripped allan head bolt from the expansion valve - they did the work as I watched 8>).
Sean and I set about finding the correct bolt as a replacement. Not shown in PET it would seem so after a lot of sloothing (sleuthing with alcohol) we found it.
I had been asked this question a few times well I now know the answer.

Part number 000 043 300 11

Expensive little bast*****

I WILL have them in stock on Tueday for $1.87 each

Sorry if this has been covered before.

jleidel

as always, you're awesome Rog!

SeanR

Remember I want 4 of them for stock. Those lil bastages irritate me.

Glenn M

I had one of those strip out, had to drill the head out. Of course it was the front expansion valve PITA! I went ahead and replaced the valve.

Nice to know there is a replacement, thanks Roger.

Dannyfumi

I would suggest to anyone replacing the o-ring or valve, Buy the new bolts! It will prevent you from having to destroy the valve the next time.

Danny

danglerb

What is this, Bolt week?

ROG100

Beats washer week

SeanR

Mike, you don't have a car new enough to worry about them. They start at 86.5.

Lizard928

Sean,

Get a small butane torch, and heat up the part the bolt goes in.

I remember removing a couple and they had some form of loctite on them.
As well, use a new good allen key (4mm iirc). I have yet to strip one.

SeanR

I've not stripped any either, but the previous people working on some of them have, and then left it in there. Yesterday is an example.

fraggle

What good timing. PM sent.

dr bob

There's a case for using a tougher bolt. Not for the threaded end but for the head. Also a case for lubricating the threads.

For those playing along at home, the later expansion valve has a couple bolts that go through plates front and rear of the valve. The plates have rounded notches/slots in them for the hard fittings to sit in, and the saddles around the notches squeeze the lines in the valve just the right amount right so the o-ring seals on them stay tight in their recesses in the expansion valve. For some reason, goofy wrench-holders feel that over-tightening those through-bolts will cure o-ring leaks on the lines attached. They are small bolts and once the plates are pulled snug against the valve itself, more tightening doesn't put any more pressure on the seals. It just stretches the bolts. No need for more than minimum torque on them, something less than 10 lbs/ft IIRC.

ROG100

Dr Bob,
Any suggestions on the tougher head?
I have the diminsions of the bolt.
Roger

dr bob

Roger--

If you can get something harder than the US-standard grade 3 you'll be ahead some. Just so it will endure the tension from the wrench without rounding out. If you can gain confidence that the installer will --religiously-- use the torque wrench, there's also a case for using a good stainless bolt in this service. There's often moisture condensing on the expansion valve in non-desert climates, so SS is appropriate except that it's generally softer than the regular steel bolts.

-----

Having a problem getting the old bolts out? A can of freeze spray may be your solution. The bolt passes through the steel front retainer plate, through the aluminum expansion valv, and threads into the rear steel retainer plate. Freezing the aluminum expansion valve between the two plates will lessen the tension on the bolt, hopefully making it easier to turn.

There's also a case for spraying the rear retainer plate with Kroil/PB/Acetone-and-ATF and letting it wick up through the back of the threads a bit. Spray and time will allow things to come loose a bit more easily.