Carburettor Question

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marquiess
Newbie
Posts: 8
Joined: Mon Nov 09, 2009 12:43 pm
My tercel:: 1984 Tercel SR5 4WD Wagon
Location: Billings MT

Carburettor Question

Post by marquiess »

Hey! Quick question about the carb. With the engine off, if i pull back the throttle whilst looking down the carb. should I see fuel spray from one of the 2 misters and if not, why not?
Thank you.
IHblarp
Advanced Member
Posts: 54
Joined: Mon Aug 24, 2009 11:01 am
My tercel:: '83 SR5, JDM 3A-SCV motor swap
Location: Las Cruces, NM

Re: Carburettor Question

Post by IHblarp »

ideally, yes you would hope to either see a spray a fuel or at least hear the squirt of fuel. How long has it been since the car has been run? If its been sitting for a while than there might not be any gas in the bowl, and therefore no gas to be sprayed into the throttle bores. you should be able to see fuel in the sight glass (small window on the side of the carb that faces the front of the car). I would check that and go from there.

Also if the car has been sitting for a while you might need to crank it for a little while to get fuel pumped up to the carb.
marquiess
Newbie
Posts: 8
Joined: Mon Nov 09, 2009 12:43 pm
My tercel:: 1984 Tercel SR5 4WD Wagon
Location: Billings MT

Re: Carburettor Question

Post by marquiess »

Thank you for the straightforward answer. No, this test was done after a carb. rebuild. Am I right in thinking that the power valve controls this?
If so then I think I might have left a ball bearing out from under the spring in the power valve chamber. I will have to disassemble the carb. and look.
IHblarp
Advanced Member
Posts: 54
Joined: Mon Aug 24, 2009 11:01 am
My tercel:: '83 SR5, JDM 3A-SCV motor swap
Location: Las Cruces, NM

Re: Carburettor Question

Post by IHblarp »

I'm by no means a carb expert so maybe someone else can correct me if i'm wrong. The actual fuel delivery is controlled by the power valve and the accelerator pump. I seem to recall that the power valve was a whole assembly and worked in series with the accelerator pump, but I could be mixing things up. Either way, if there is a possibility that something got left out than maybe it's time to tear back into it to check. Good luck!!
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Petros
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Posts: 11941
Joined: Sun Jan 28, 2007 6:31 pm
My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: Carburettor Question

Post by Petros »

with the engine warm, off, and the air cleaner off, if you rapidly open the throttle you should see a strong stream of fuel squirting down the barrel, use a strong flash light to know for sure. IF it is weak, sputter or non-existent, you need to replace the accelerator pump. If you open the throttle slowly you will not get much of a stream, it has to be a rapid opening of the throttle.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
marquiess
Newbie
Posts: 8
Joined: Mon Nov 09, 2009 12:43 pm
My tercel:: 1984 Tercel SR5 4WD Wagon
Location: Billings MT

Re: Carburettor Question

Post by marquiess »

I removed the carb. again and found that two of the 4 bolts underneath the carb. were in the wrong hole. One has a hole in it and was in the wrong side. Also noticed that there was a vacuum line in the wrong spot also. Started up and runs perfect now.
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