We're bringin' back the Flat Tops!

[motorman7]

Will have to look into the Freeze Off spray.  Just found it on line.

[Captain Obvious]

15 hours ago, motorman7 said:

it's hard not to damage the nut when trying to unloosen them.

Well there's your problem... Maybe try loosening them instead of unloosening them? 

Seriously though, good luck with the endeavor. My only word of advice is of potential personal safety...

The active ingredient in that freeze spray stuff (R152) is difluoroethane, and I'm no expert on the topic, but one of the components of flame decomposition of many of the fluorocarbons is hydrogen fluoride gas. Problem with hydrogen fluoride gas is that it turns into hydrofluoric acid when it comes into contact with water. And as a fictional silicon life form once pointed out, you're a bag of mostly water.

Short story? I'm certainly no expert in the field, but I don't think it would be a good idea to work with a torch in one hand and the freeze spray can in the other and don't light the freeze spray on fire.

Speaking of such things, I did exactly that with a can of R134 (tetrafluoroethane) a coupe months ago. And 24 hours later, based on the corrosion spray pattern behind what I was working on, I think I created some hydrofluoric. I had all the ingredients there at the same time. Very very nasty stuff.

Edited January 16, 2019 by Captain Obvious

[motorman7]

I was able to get two of the fittings to loosen on one of the manifolds.  That is very promising.  The other four on that same manifold would not budge.  So, I think I will let them soak some more and try again on Thursday.  No rush as this would be worth the wait.  The fire and ice seems to work pretty well.  Hopefully it will allow the Kroil to penetrate a little deeper on the fittings that would not move.  The second manifold wasn't moving at all.  So, I think I will continue to soak that one as well.

I took the throttle shafts into Olympic coatings for a dry film lube coating.  This should hopefully replicate the previous green coating that was on the throttle shafts.  Forgot to take before pics on these.

Also got a couple tires in today from @jayhawk.  I will wait till later before I unwrap them.  Pretty sure they are some nice Bridgestones.

[grannyknot]

9 hours ago, Captain Obvious said:

you're a bag of mostly water.

"ugly bags of mostly water"  I think, says another STNG geek.

 

11 hours ago, Patcon said:

You could get some Freeze Off spray. I think CRC makes it. I have had good luck with it and a torch.

Funny you say that because I have never seen it work yet,  I have even sprayed my hand with it and the skin only feels cool  not -42*C                 But then I live up here so my Government has probably taken the good stuff out!

9 hours ago, motorman7 said:

I took the throttle shafts into Olympic coatings for a dry film lube coating.  This should hopefully replicate the previous green coating that was on the throttle shafts. 

So dry film lube coatings are offered in different colours?  That's good info.

[Captain Obvious]

2 hours ago, grannyknot said:

"ugly bags of mostly water"  I think, says another STNG geek.

Haha!!! Exactly! That's the one!

 I was just leaving the (subjective) "ugly" portion out of it and was letting that part up to the interpreter.      

[motorman7]

13 hours ago, Captain Obvious said:

The active ingredient in that freeze spray stuff (R152) is difluoroethane, and I'm no expert on the topic, but one of the components of flame decomposition of many of the fluorocarbons is hydrogen fluoride gas. Problem with hydrogen fluoride gas is that it turns into hydrofluoric acid when it comes into contact with water. And as a fictional silicon life form once pointed out, you're a bag of mostly water.

I didn't check the chemistry (not my field of expertise) but I figure the fumes from the Kroil and PB Blaster are probably not good for you either.  Did my best to keep away from that stuff.

 

3 hours ago, grannyknot said:

So dry film lube coatings are offered in different colours?  That's good info.

I should clarify, the color of the dry film lube for this application is dark grayish.  My intent was not so much the color replication, but the surface build-up and the bearing surface.  The shaft is pretty much encapsulated, so the color will not be visible.  Also, the dry film lube finish seems to be very durable.  They use it to coat the piston skirts on racing engines.

 

And yes, I did have to google STNG ?

Edited January 16, 2019 by motorman7

[Captain Obvious]

Yeah, the chemistry isn't anywhere near my field of expertise either. But I do know that hydrofluoric acid is really nasty stuff due to it's affinity for calcium of which you have a bunch inside your bag of water. Here's two garage rules...

Don't burn any of the fluorocarbons due to the risk of creating hydrofluoric acid.
Don't electric weld anywhere around chlorinated carb cleaners due to the risk of creating phosgene.

You, being in CA, probably can't get your hands on any chlorinated cleaners anymore.

https://www.youtube.com/watch?v=paH97dYR6Lg

[motorman7]

Got parts back from plating.  Sorted these into separate boxes to help keep things organized.  Items are categorized as, Nuts, Bolts, Washers, Brake parts, Carb and Smog parts, small screws and washers, silver zinc parts, and misc.  That will help when I start putting things back together.

[Zup]

On ‎1‎/‎10‎/‎2019 at 10:45 PM, motorman7 said:

I actually had an old '73 exhaust manifold laying around

or 2 it would seem.

Are those manifolds from a 73? Mine is a completely different casting---N33.

This photo is from when I installed a new air galley. It isn't as easy to install as one would think. (you know that)

One of the biggest disappointments I have had is that once the exhaust manifold with new air galley was installed on the engine, the air galley tube discolored badly soon afterward from the heat.

I don't know of any way to prevent it from happening and have wondered several times if the plating has changed on the new tubes and just doesn't hold up as well. I do know it is more of a silver-ish cast than the yellow zinc plate you typically see on plated parts.

Would re-plating a new one by sending it out to Sav-On Plating result in a more durable finish?

Thoughts???

[motorman7]

10 hours ago, Zup said:

 

Are those manifolds from a 73? Mine is a completely different casting---N33.

This photo is from when I installed a new air galley. It isn't as easy to install as one would think. (you know that)

One of the biggest disappointments I have had is that once the exhaust manifold with new air galley was installed on the engine, the air galley tube discolored badly soon afterward from the heat.

I don't know of any way to prevent it from happening and have wondered several times if the plating has changed on the new tubes and just doesn't hold up as well. I do know it is more of a silver-ish cast than the yellow zinc plate you typically see on plated parts.

Would re-plating a new one by sending it out to Sav-On Plating result in a more durable finish?

Thoughts???

 

Hi Jim,

     Actually, the two shown are not for this car and are for earlier models (E30 and ?,  I probably should not have included them on this thread) .  They do not have the side port near the outlet which is unique to the '73 and '74s.  The '73 manifold, I'm guessing early '73 (N36), has the side port as shown below and in earlier post.  As you know, there is a tube that routes from this port up to the balance tube. On the '73 exhaust manifold, I drilled and tapped the smog ports.  You can actually see part of that manifold in one of the above pics (3 manifolds).  Also, I re-posted the '73 manifold pics below.  The '74 manifold are much larger as seen in your picture.  Not sure when the change came about for the larger size, but both have the side port.

     Yes, funny thing about the air galley and the discoloration.  Not sure if there is any way to prevent that.  It seems to discolor more if you disable the air pump which probably gets the air galley real hot since there is nothing to cool it down.  It does appear that after the initial discoloration that the color stabilizes which is a good thing.  And, I really don't have enough experience with the different platers to know which ones have a better finish or not.  Will have to see how the air galley for this '73 does as it is NOS.  Hopefully that does well.

[Zup]

Thanks for the clarification Rich! I was unaware of the change made to the manifold.

My 73 is a 6/73 build date, so being fairly late it may have received the 74 exhaust manifold.

Sure hope you have good results with your new air galleys, and yes, I agree that the air pump functioning should/ would indeed help reduce temperatures in the air galley.

Those galleys have gotten crazy expensive, so it's no trivial pursuit to recondition used if at all possible.

[motorman7]

Started the carb re-assembly now that I have freshly plated parts.  This is actually a lot of fun to re-assemble using the new gasket kits.  Fortunately, I have a spare set of flat tops to look at to make sure that everything goes together right.  Also have the 'upgrade' guide.  Replaced all the gaskets on the pump assembly.  Interestingly, it looks like the original one was folded over as you can see in the last pic.  Choke mechanism works nice.  My throttle shafts are supposed to be ready tomorrow with fresh dry film lube.  Should be able to finish things out once I get those.