Carburetor Mounting Gasket Question

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ARCHINSTL
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My tercel:: Goldie is a 1986 SR5 attualmente con Weber/also owned the first T4WD in STL in late '82
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Carburetor Mounting Gasket Question

Post by ARCHINSTL »

Well - pardon my ignorance and/or confusion...
I received the carb from National [new accelerator pump and diaphragm (AAP?) and cleaned a nozzle (?), all at N/C]; I checked all of the '05 vac lines and replaced a couple; I replaced the fuel pump to carb line; I unplugged the "A" switch's vac line. It's stopped raining, so I can get out.

Questions:
1. Should I install an additional in-line filter between the pump and carb? It seems redundant, as there was no crud in the old line (which was replaced when I installed the new pump in '05) and there has been no sign of any crud or rust in the prior 3 filters. Just thought I'd ask, because of National's report of cleaning "trash" from the nozzle.

2. Please refer to the photo of the three gaskets National supplied with the carb. These are the same gaskets it supplied when I got the carb from it in '05. I had already replaced the gasket between the manifold and the heat shield and the one between the shield and the cold mixture heater plate; they were not disturbed with the recent removal.
When I replaced the carb in '05, it seemed logical to use gasket #3. Now I am not too certain. The blasted FSM gives no clue as to which one to use, and a 'Net search turns up nada as well - also searched 4AC info.
# 1 gives coverage between the throats, but the gasket will block the top vacuum screw from vac access to either throat when seated, and the right vac port is partially blocked (although the base is notched, so some vac will be available).
# 2 opens up the ports, but also opens a wide gap between the throats - and the vac ports can also draw from either/both throats. It seems the least logical to use (this is also the one I used under the heater plate and under the shield).
# 3 still seems the most logical, but I wonder if I should open up the vac screw's access to the primary throat passage a bit - ditto the secondary throat's vac port?

I realize some folks are throwing up their hands at my dithering, but I really want to try to cure a couple of the minor annoyances. I am inclined to again use #3, and just clip the areas around the vac holes a bit. I do use a light film of Permatex red sealant on gaskets, and I do use a torque wrench on the fasteners.

Does anyone really know what actually came OE on this?
Thanks.
Tom M.

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Typrus
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Post by Typrus »

The carb off my 84 appears to be using the #2 one. At least, the witness marks in it look a whole lot like that one.
RIP 10-07- 1984 Toyota Tercel SR5 4wd Wagen 6 speed

RIP 04-05- 1986 Toyota Tercel SR5 4wd Wagen 6 speed

1st Terc- 1987 Tercel SR5 4wd Wagon 6-speed, Sadly cubed

1985 Tercel Standard 4wd Wagon w/ 3-speed auto, Living a happy life in Boulder last I knew
keith
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Post by keith »

#2
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My tercel:: Goldie is a 1986 SR5 attualmente con Weber/also owned the first T4WD in STL in late '82
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Post by ARCHINSTL »

Ok for all to titter at this, but I finally decided on the proper gasket:
Keith and Typrus, the dynamic duo, got me to rethink my previous gasket choice. So I again went to eBay, and tracked down 4 Corolla and a couple of Tercel vintage Aisans, and they all bore "witness marks" * to gasket # 4 below.
So - I think that is the OE-style.

Now, I did not take another photo; I just digitally manipulated some pix to get the #4 photo, but you get the idea.
Tom M.
* Typrus - where did you encounter the term "witness marks?" It makes perfect sense - a new and quite appropriate term for the condition.
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T4WD augury?
"Oh, do not ask, 'What is it?' Let us go and make our visit."
T.S. Eliot - "The Love Song of J. Alfred Prufrock"
"Now and then we had a hope that, if we lived and were good, God would permit us to be pirates."
Mark Twain
keith
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Post by keith »

Original carburetor from the federal engine. As far as I know, its the factory gasket.

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My tercel:: Goldie is a 1986 SR5 attualmente con Weber/also owned the first T4WD in STL in late '82
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Post by ARCHINSTL »

Right on!
Looking at this makes me realize why I don't think my secondary opened - or if it did, why it was cautious.
Not enough vac was available to "flow" to its small entry port using my previous choice of # 3 ?
We shall see - whenever it stops raining...
Thanks, guys.
Tom M.
T4WD augury?
"Oh, do not ask, 'What is it?' Let us go and make our visit."
T.S. Eliot - "The Love Song of J. Alfred Prufrock"
"Now and then we had a hope that, if we lived and were good, God would permit us to be pirates."
Mark Twain
Typrus
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Post by Typrus »

I actually don't remember. Hell, I might have coined it. I really can't say for sure I've been using it for so long.

I was wondering the same myself....
RIP 10-07- 1984 Toyota Tercel SR5 4wd Wagen 6 speed

RIP 04-05- 1986 Toyota Tercel SR5 4wd Wagen 6 speed

1st Terc- 1987 Tercel SR5 4wd Wagon 6-speed, Sadly cubed

1985 Tercel Standard 4wd Wagon w/ 3-speed auto, Living a happy life in Boulder last I knew
User avatar
ARCHINSTL
Goldie Forever
Posts: 6369
Joined: Sat Apr 30, 2005 1:52 pm
My tercel:: Goldie is a 1986 SR5 attualmente con Weber/also owned the first T4WD in STL in late '82
Location: Kirkwood, a 'burb of St. Louis

Post by ARCHINSTL »

While keith confirmed it, #4 is definitely the way to go - having the "barrier" of the gasket between the barrels apparently inhibited the secondary from opening.
The second choice would be, obviously, # 2.
When I bought my gaskets in '05 from AZ (or ADV), the choices were #2 and #3 - not # 4. And I guessed incorrectly in installing #3.
Tom M.
T4WD augury?
"Oh, do not ask, 'What is it?' Let us go and make our visit."
T.S. Eliot - "The Love Song of J. Alfred Prufrock"
"Now and then we had a hope that, if we lived and were good, God would permit us to be pirates."
Mark Twain
takza
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Post by takza »

Maybe it is more a matter of those holes in the bottom of the carb? Where various areas of the carb get vacuum from?

2nd-dary needs vac to operate?
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