Griffith's AC upgrade for '84 911 install thread

[Skip1]

Originally Posted by Bob Kontak

Expand on this, Skip. I see some corrosion but what did you see to think this was the cause of poor/no function?

Bob,

It was a combination really, inital shock , but upon closer inspection the tubing was cracked in one place that I couild see and the capillary tube? at the entry point was broken as well. The hole system has also been "open" for years (with no compressor attached), the motor also didn't function. Perhaps the evaporator could have been saved but I figured, nah, get-er-done while I'm in there.

[Skip1]

Originally Posted by wwest

I know my 78 is different, but is the 84 model different from my '88?

I seem to remember the evaporator squirrel cage blower wheel in my '88 looking more complex than the one in these pictures.

The picture I took is of the "new" assembly, I had already removed the old motor and supporting plastic supports x4 using a saws-all blade (hand power) to neatly trim back the plastic supports. I think I took a picture of the "before" view of teh motor / squirrel cage. Will take a look tonight. As for difference in years, I think there was a change for the '86 model year, but can't really explain - but the top looks different from the outside I think as a minmum.

[Skip1]

Originally Posted by wwest

Those refrigerant connections should be covered some how until you're ready to connect them up.

All the lines are also being replaced, just haven't gotten there yet, but yes, excellent tip. Thanks.

[wwest]

Originally Posted by Skip1

The picture I took is of the "new" assembly, I had already removed the old motor and supporting plastic supports x4 using a saws-all blade (hand power) to neatly trim back the plastic supports. I think I took a picture of the "before" view of teh motor / squirrel cage. Will take a look tonight. As for difference in years, I think there was a change for the '86 model year, but can't really explain - but the top looks different from the outside I think as a minmum.

I looked it up...researched it (Googled it ) Yes, there was a change in 86, at least in the design of the motor and the blower wheel, the pre-'86 looks simplistic in comparison.

I see an update coming for my '78, anyone know if they are interchangeable and how much gain in CFM?

[wwest]

Originally Posted by Ronnie's.930

Why would I want to drive around here in Texass in a sauna-mobile (you know, when the a/c thinks it's the heater) ?!?!

Not to worry...

I looked up an old engineer friend from my days at Boeing (~68), he's now retired and living just south of you in Cleburne. He jumped at the chance for a paid trip to Seattle and drive an '88 back home.

He will get in touch with you come August, in the meantime keeping records of A/C performance.

We will not be trying to please you with your non-normal metabolism, your wife maybe with you taking a back seat?

[Bob Kontak]

Originally Posted by wwest

We will not be trying to please you with your non-normal metabolism, your wife maybe with you taking a back seat?

This is awesome.

Ronnie sits in the back seat, period.

If your system is working well, there is no way the chicken hed will lie.

[Skip1]

So some minor gains last night, with only a couple of hours available. Was able (with numerous work related interuptions) to complete the installtion of the new thermostatic tube through the console, bulkhead and forward to the new rebuilt evaporator box. Also able to coil the excess (used a Coke bottle to ensure it was round / non-kinked in any way. Was a challenge to say the least, but definitely satisfied that that piece is done. The only part I need to sort out is at the console (had to drill out the facia a bit as per instructions for the new switch to fit through), but the tube which comes out the top of teh switch, butts up against the top of the console, with no ability to "cut a space" that I can see - nor want to attempt. I believe I should bend the tube a little bit, but am reticent in how to do it, so close to the switch without cracking it or pulling it out. Other than that, it's now snug and set up. Tested out the new fan switch, which works great the the LED comes on right away in its orange hue - so all good. May try to find time this evening to figure out the console clearance issue and install the new fan in the front condensor fan houseing, but then I'll likely be on pause for a couple of weeks due to visitors to the house.

[DaveMcKenz]

Great Skip.
If you are in need of a new battery, you might consider a group 48 size. It's maybe 2" shorter than group 49. It will give a little extra room near the new and possibly slightly bigger condenser fan.
Good luck,
Dave

[kingddv]

I installed Griffith's barrier hoses over the weekend. Took about 10 hours spread over two days, including beer breaks and time to replace two weeping valve cover gaskets.

[wwest]

Originally Posted by Skip1

So some minor gains last night, with only a couple of hours available. Was able (with numerous work related interuptions) to complete the installtion of the new thermostatic tube through the console, bulkhead and forward to the new rebuilt evaporator box. Also able to coil the excess (used a Coke bottle to ensure it was round / non-kinked in any way. Was a challenge to say the least, but definitely satisfied that that piece is done. The only part I need to sort out is at the console (had to drill out the facia a bit as per instructions for the new switch to fit through), but the tube which comes out the top of teh switch, butts up against the top of the console, with no ability to "cut a space" that I can see - nor want to attempt. I believe I should bend the tube a little bit, but am reticent in how to do it, so close to the switch without cracking it or pulling it out. Other than that, it's now snug and set up. Tested out the new fan switch, which works great the the LED comes on right away in its orange hue - so all good. May try to find time this evening to figure out the console clearance issue and install the new fan in the front condensor fan houseing, but then I'll likely be on pause for a couple of weeks due to visitors to the house.

Is the hole in the console "keyed" in some way that prevents you from rotating the switch 180 degrees so the capillary tube doesn't contact or rub the console? Rather than attempt tight radius bending of the tube I would suggest drilling out the "key".

[wwest]

Originally Posted by Skip1

The picture I took is of the "new" assembly, I had already removed the old motor and supporting plastic supports x4 using a saws-all blade (hand power) to neatly trim back the plastic supports. I think I took a picture of the "before" view of teh motor / squirrel cage. Will take a look tonight. As for difference in years, I think there was a change for the '86 model year, but can't really explain - but the top looks different from the outside I think as a minmum.

Hindsight is always 100% correct but it might have been a good idea to find a used 86 or after plenum/blower and upgrade THAT motor.

Does anyone have an idea of the CFM gain of the 86+ blower vs previous?

[Skip1]

Originally Posted by wwest

Is the hole in the console "keyed" in some way that prevents you from rotating the switch 180 degrees so the capillary tube doesn't contact or rub the console? Rather than attempt tight radius bending of the tube I would suggest drilling out the "key".

WWest: Not sure what a "key" is specifically in my case but assume it's something like one side is flat, thereby only allowing the switch to fit one way. The facia simply has two round holes that had to be drilled out a little for the new switches. That said, your comment gave me an idea. I couldn't rotate the switch 180 degrees as then the tube would be tight against the base, but I thought, what about 90 degrees, so the tube is actually on the side between the two switches. There is just enough clearance on the driver side of the console, to butt up the switch if I drilled out about 2mm to expand the facia hole in the direction of the passenger side. There is no wiggle room, as the one side is flush, and now the end of the switch protrudes perfectly, and the problem is solved. Thanks for the idea - it sorted me out.

[Skip1]

Originally Posted by DaveMcKenz

Great Skip.
If you are in need of a new battery, you might consider a group 48 size. It's maybe 2" shorter than group 49. It will give a little extra room near the new and possibly slightly bigger condenser fan.
Good luck,
Dave

For better or worse, I don't need a new battery - it's only a year old, so it is pretty close to the fan - will have to see what the effect is. Thanks.

[wwest]

If I remember correctly the battery must be pulled to access and remove (CAREFULLY....!!) the blower assembly.

Easy to break, if not already so.

When you're all done with the Griffiths kit installation we can talk about a stud mounted thermostatic switch on top of the R/D to power the front lip blower only as required. Not so sure about Griffith's aftermarket front lip condenser but the factory one benefits so greatly from forward motion cooling airflow that the blower can be de-powered >20 MPH.

In my own case the additional cooling airflow (only as required) through the rear lid condenser from the Spal fans allowed me to completely de-power the front blower.

[wwest]

Bad timing on my part but did you check the thermostatic switch calibration before you started the install process??

You may not wish to use the "factory" calibration since it might be calibrated such that at full CW the evaporator will "ICE" over if you are not quick enough to note the slow degradation of system airflow volume.

If not, then now might be a good time.

[zippy_gg]

Skip, have you put the console back on already? if not then it will be easier to install the Khuel center vent.

[wwest]

You can have moderately less restriction to air outflow from the system, more outflow volume, by simply removing the firewall distribution "bowtie".

Generally you only need "directed" airflow during the initial cabin atmosphere cooldown period.

Beyond that "directed" airflow can be discomforting so most of us would re-direct the coolish airflow away from our face and upper body.

Unless you have a system with sub-standard cooling performance which most certainly should not be the case with even 1/3 of the Griffiths kit installed. Most functional 1/3, of course.

[Skip1]

Originally Posted by wwest

If I remember correctly the battery must be pulled to access and remove (CAREFULLY....!!) the blower assembly.

Easy to break, if not already so.

When you're all done with the Griffiths kit installation we can talk about a stud mounted thermostatic switch on top of the R/D to power the front lip blower only as required. Not so sure about Griffith's aftermarket front lip condenser but the factory one benefits so greatly from forward motion cooling airflow that the blower can be de-powered >20 MPH.

In my own case the additional cooling airflow (only as required) through the rear lid condenser from the Spal fans allowed me to completely de-power the front blower.

I'll be quite careful, and probably will remove the battery due to the challenge of reinserting the air intake tube into the body if the batter is in place. Interesting idea about powering down the front condenser fan - will keep it in mind, thanks.

[Skip1]

Originally Posted by zippy_gg

Skip, have you put the console back on already? if not then it will be easier to install the Khuel center vent.

Already reinstalled. The vents will still be several weeks away, and I want to drive the car without pieces flying about unnecessarily when crossing the 200 km/h mark on the Autobahn. Will likely just drop it back down as necessary, but thanks for the recommendation.

[Skip1]

Originally Posted by wwest

Bad timing on my part but did you check the thermostatic switch calibration before you started the install process??

You may not wish to use the "factory" calibration since it might be calibrated such that at full CW the evaporator will "ICE" over if you are not quick enough to note the slow degradation of system airflow volume.

If not, then now might be a good time.

I did not, as I wouldn't know where to begin - as I said, I'm a newbie at AC systems. The console is all reassembled now, as is the evaporator.