Troubles after carburetor rebuild

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Q23456789
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Posts: 17
Joined: Sat Sep 30, 2017 6:06 pm
My tercel:: 1984 4wd Tercel, stock

Re: Troubles after carburetor rebuild

Post by Q23456789 »

Another update.

The car seems to be running pretty good, it idles okay and drives really well. It still has a tiny vacuum leak through the intake gasket, which is pretty frustrating because I just replaced it. For now, it is running smooth enough to make me happy.

New problem though. It drives great, but every once in a while it will start bucking and bouncing and lose power. It happens mostly when going up long hills, but I have had it happen on flat ground too. Most of the time when I pull over, it starts and runs fine and I can get it home. One time it happened it didn't want to start at all. I pulled the fuel line off of the pump and it was completely dry. I blew it out and sucked fuel back up the line and plugged it back onto the pump, and it started and ran fine. Pulled the sending unit out of the tank, and sure enough there is a HUGE pile of crud around the fuel pickup strainer. So I am pretty sure that's the issue, but looking back at my history the obvious problem doesn't ever seem to fix it. I am going to drop the tank and clean out all the crud and hope that fixes it. Are there any other reasons this might be happening that I can check out?
xirdneh
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My tercel:: 87 tercel 4x4 wagon w/reringed engine, 83 tercel 4x4 wagon w/salvaged engine and 4.1 Diff's
Location: seabeck, washington, USA

Re: Troubles after carburetor rebuild

Post by xirdneh »

I would check the two graphite plungers inside the distributor cap first. Make sure they are not sticking.
Love those Tercell 4x4 wagons but they sure suffer from road noise.
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Petros
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My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: Troubles after carburetor rebuild

Post by Petros »

your symptoms sounds like loose crud in the fuel system. there is a screen on the end of the fuel line pick up and larger particles get hung up on it, eventually cutting off and limiting the amount of fuel that reaches the engine. What is frustrating about it is that when you go up a long hill, or when at sustained high speed, where the fuel demand is highest, it will suddenly sputter and cough. when you slow down, or to get to the top of the hill, it runs normal again. Starts and idles fine, but wills stumble during high fuel demand conditions. A partially blocked fuel filter will also act like this, so that is the first thing to check and replace (they are cheap), next is inspect the inside of the tank, as you have found.

Best solution is to clean out the tank. Removing it is a somewhat troublesome job if the fuel line fittings are all corroded and stuck, you likely will damage them trying to undo them. Not always, but on something this old that has never been taken apart, it is a very real possibility. You can save the trouble of removing it by flushing it in place: remove the drain plug, and the sender intake, drain and flush several times until it is clear (you can filter and use the "flush" fuel in your lawn mower or other small engine). If the inside of the tank is in other wise good condition, you can just put it back to gather. contaminated fuel or something dumped down the in let might have been the source of loose crud, so just flushing will fix it.

However, it if there are rust spots inside the tank, it should be replaced, or if not too bad, removed and taken to a shop that can boil it out. Than a liquid fuel tank liner is sloshed around inside the tank that will seal the oxidized tank walls. It is like a tough fuel resistant paint that will seal the inside of the tank. Check costs first of course, sometimes replacing the tank is cheaper, but it gives you a way of fixing the old one if a replacement tank is not available.

You can also consider removing the screen from the fuel line inlet, but it means you should check and replace the regular fuel filter under the hood often.

Good luck.
'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)
Q23456789
Newbie
Posts: 17
Joined: Sat Sep 30, 2017 6:06 pm
My tercel:: 1984 4wd Tercel, stock

Re: Troubles after carburetor rebuild

Post by Q23456789 »

Thanks for all the help, again.

I mocked up a temporary gas tank inside the engine bay and took it for a drive. Went up the same hills it struggled up before, and it took them perfectly fine! So either the Tercel is giving me false hope so it can crush my dreams, or I need to clean that tank.

I didn't think about flushing the tank still in the vehicle, I will try that out and see how it works.
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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
Location: Kirkwood, a 'burb of St. Louis

Re: Troubles after carburetor rebuild

Post by ARCHINSTL »

Q23456789 wrote: Tue Oct 17, 2017 8:00 pm So either the Tercel is giving me false hope so it can crush my dreams ...
Totally OT, but I had to smile at your line; haven't we all been there before, with one vehicle or another?
My Pandora's Box was a '52 Singer Roadster, many, many, decades ago.

More to the point - Petros' mention of having the tank boiled out and "relined" was good; a friend did that on his '58 MG A years ago and it has been fine since (naturally, it is not a DD, so sits for a month or so between drives, and even longer during the 30-plus years he has owned it).
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
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Petros
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My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: Troubles after carburetor rebuild

Post by Petros »

isolating problems with older cars can be very frustrating, and often discouraging, but almost all problems are fixable once you find them.

You have no false hope, it is real hope. but you have to find it first, which often can be more time consuming and frustrating than the actual repair.

Be assured, you can find the problem, and you can get it fixed. ONce that happens it will run good and be a great daily driver...until the next thing wears out...
'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)
Q23456789
Newbie
Posts: 17
Joined: Sat Sep 30, 2017 6:06 pm
My tercel:: 1984 4wd Tercel, stock

Re: Troubles after carburetor rebuild

Post by Q23456789 »

Sorry for the long time between updates here, been working a lot lately.

So I cleaned out the fuel tank in the vehicle as best I could. Ran water through it probably a hundred times, and then flushed all the water out by dumping fresh fuel in it several times and filtering the water from the fuel. There was still a bit of crud in there, but i got most of it out. In the process, one of the screens came off the strainer in the tank so I popped it off and pulled it out, but couldn't replace it because the tank was still in the car. So I put an additional clear pre-filter in right before the fuel filter.

Got everything back together and drove the car about 15 miles, it started bucking and died again. Checked the pre-filter, and sure enough it was plugged. Swapped it out with another one on the side of the road, started right up and drove home. Drives great as long as that filter isn't Plugged! Went up the hills it was dying on before and it did them without any problems. Took it on the freeway, drove great. I figure I will probably have to change this filter at least once or twice more before I get all of the crud out, so I bought a few extra and put them in the glove box.

The car still doesn't seem to want to pick an idle, it's been idling all day around 1400 rpms, and then at some point raised to around 1600, and then back to 1400, then dropped way down to 800. Fuel filter could be getting plugged again, but it looks okay from the outside, so I am not sure.

Thanks for all of the help. I think I have gotten my major issues out of the way and it's just a matter of fine tubing everything now.
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Petros
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My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: Troubles after carburetor rebuild

Post by Petros »

you may have had some crud in the lines too, sounds like most if it clean out now. But you are doing the right thing for now, just carry the extra filters, either it will all work out or you will replace the fuel tank, and perhaps the fuel line as well.

the irregular idle is common on a car with a worn out carb, various places seep air into the carb (throttle shaft, vac lines, etc). do a careful check of all the vac lines for cracks or leaks, and correct routing, that should help. but you many not get it completely solved even with no vac leaks, hard parts wear out and cause unstable idle. If you have not other drivablity issues, than you can just live with it.

good luck
'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)
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