carb and exhaust

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timothygodden
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Posts: 163
Joined: Mon Dec 31, 2012 12:45 am
My tercel:: 84 tercel 4wd sr5 lifted, modified head, delta cam, 2" exhaust
Location: seattle wa

carb and exhaust

Post by timothygodden »

recently finished a long list of repairs on "the nomad"(84 tercel 4wd sr5) brakes, rotors, radiator, cooling fan, manifold and gasket. cv's and clutch thank you xirdneh for your transmission removal and dlb for the clutch recomendation. the head gasket timing and idle thank you petros no more high temps and a lot more pep for sure. and thanks to everyone else for all the topics and post to gather information from i have never done any of these projects before and it would not have been possible without this forum.
now to the carb. works great most of the time but every few times i come off the gas the idle doesn't drop back to 800 it'll settle at 1000-1300 instead usually a couple of taps on the pedal will get it to go back to 800. any ideas? and it will also sputter a bit at beginning of a heavy throttle. any tips or threads on this would be appreciated.
also my exhaust is shot, all this work, my car runs greats but sounds like it's on it's death bed. was gonna piece together a new exhaust 2 inch or 2.25 depending on what would be best. was hoping on pointers on size, gauge, angles, and a good muffler. maybe even plans from some one who has done this before. i would be grateful for any and all help.
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dlb
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My tercel:: '87 sr5, '83 dlx parts car
Location: bc, canada

Re: carb and exhaust

Post by dlb »

for the intermittent high idle, i would spray the throttle linkage with pb blaster or something similar and check for tension on the throttle cable. the cable should have lots of slack when at rest. also make sure that the bolt or screw holding the throttle arm to the carb isn't too tight, causing the arm to bind sometimes.

sputtering on initial hard throttle might be the injector pump? can't remember if that's the name or not. easy check though: with the air filter lid off and the choke wide up, look down the barrel of the carb. use a hand to twist the throttle arm to full. you should see a big squirt of fuel in one of the barrels. if you don't, the pump is faulty.

could also just be a vacuum leak though. make sure all the hoses are correctly routed and fully connected, and suck on each diaphragm to make sure they are still good. if you can suck air through, the diaphragm is broken and should be replaced. disconnect and plug the hose going to it until you can replace it.
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rer233
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My tercel:: Multiple

Re: carb and exhaust

Post by rer233 »

Could also be the mechanical advance sluggish in the distributor.
if it aint there, there's a good chance it won't break!
83 SR5 Silver/Blue (Snowmobile/work beater)-totaled but drivable
85 SR5 Blue
88 SR5 White (the 'good' one)-not anymore-totaled
87 fwd silver wagon a/t
87 4wd dx Cream (a/t- not anymore- now m/t)
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dlb
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Posts: 7447
Joined: Mon Jul 06, 2009 9:03 pm
My tercel:: '87 sr5, '83 dlx parts car
Location: bc, canada

Re: carb and exhaust

Post by dlb »

rer233 wrote:Could also be the mechanical advance sluggish in the distributor.
that's a good point. easy test for the advance mechanism: remove the distributor cap and try to twist the rotor counter clockwise. it should have a small amount of spring-loaded play. if it doesn't, you need to disassemble the dizzy and re-grease the advance mechanism. might sound intimidating but it's easy. takes an hour or two.
timothygodden
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Posts: 163
Joined: Mon Dec 31, 2012 12:45 am
My tercel:: 84 tercel 4wd sr5 lifted, modified head, delta cam, 2" exhaust
Location: seattle wa

Re: carb and exhaust

Post by timothygodden »

seems to be the injector pump as you said no big squirt of fuel in the barrel. there is free play in the dizzy but would it still be beneficial to take it apart anyways? is the injector pump easy to fix is there a repair guide on here for it?
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dlb
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Joined: Mon Jul 06, 2009 9:03 pm
My tercel:: '87 sr5, '83 dlx parts car
Location: bc, canada

Re: carb and exhaust

Post by dlb »

you need to take the carb top off to access the injector pump but at that point you should probably do the full rebuild. rebuild kits are cheap, like $30-$40, and there are instructions both in the kit and here on the forum. xirdneh did a good write up in the repair guides section called 'carb rebuild' or something like that, and it is also covered in the FSM under the fuel section.

sounds like your dizzy is fine. no need to mess with it.
larry mcgrath
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My tercel:: 83 tercel v20 B/T (The ROCKET)98 toyota t100
Location: Wilds of Montana

Re: carb and exhaust

Post by larry mcgrath »

the injector pump is called the accelerator pump (this circut in the carb supplys fuel for a smooth transition from the idle circut to the low speed circut in the carb, if it's not functioning right you end up with a Flat spot on acceloration. The acc-pump piston is made of leather which wears out over time and the assy needs to be replaced, it's quite common for the check ball in the acc pump well to corode and stick ,not allowing the pump to draw in a full load of fuel every time, in the FSM you will see it in the diagram at the bottom of the acc pump well ,the check ball is about 1/8" diameter. Larry
timothygodden
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Posts: 163
Joined: Mon Dec 31, 2012 12:45 am
My tercel:: 84 tercel 4wd sr5 lifted, modified head, delta cam, 2" exhaust
Location: seattle wa

Re: carb and exhaust

Post by timothygodden »

found some good info in the repair guides should help along the project. any recommendations on a rebuild kit? are they all the same or will spending a bit extra make any noticeable difference?
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