carberator

[dlb]

i wouldn't say rebuilding your carb was a waste of money, geoedb. i don't even know if your carb has a throttle shaft leak. i just know that it is common on old carbs due to wear and that it attributed to a high idle on my carb.

[TURTCEL]

Hi, I 'am looking for a rebuilt or new carberator for a 85 4wd Tercel mine is about gone. Does anybody have one or know where i can pick one up at a fairly decent price? I live north of Seattle in Marysville. Thankyou

I live in Everett and I have a rebuilt carb if you are interested. Another forum member rebuilt it and it has not been installed since its rebuild. I acquired in part of a trade. $50 (as is) if you are interested.

PM me if you would like to inquire further.

Peace

[geoedb]

The rough idle and smoking are only when the engine is cold, might be the bad CMH.

I decided to check the timing again after talking to the smog shop.
I get something in the range of 30-35* btdc, I was only able to adjust it down to 25*.
I went by the smog shop to check my reading, we got 20*.
A month before when I replaced the plugs, adjusted the valve clearance, and set the timing, it was 5* btdc & 13* btdc retarded.
I did replace the cap afterwords, some vacuum hoses, etc.
But none of this should have affected the timing.

I went home, finally decided to pull the distributor, and reinstalled according to the FSM.
Still 30* btdc or so.
I tried to rotate it 180*, but than it wouldn't start, switched it back.

The #1 cylinder (front) was tdc (vacuum hose barely went in), and the distributor installed centered with marks aligned.
Since everything is connected with gears I don't understand how it could have changed the past month.

What am I missing?
How to I adjust it correctly? (do I have to "miss align" the distributor marks?

[Petros]

you may have indeed got the distributor gear off a tooth or two. two things: did you check the timing with the vac lines disconnected and plugged, with idle at about 800 rpm? If not that would account for it being off. did you verify you are actually with #1 cylinder at TDC and not just when the piston is at the top. both valves have to closed at the end of the compression stroke. there is another time the piston is at the top of the stroke and it is not at TDC, but rather between the exhaust stroke, and the next intake stroke, both vales are slightly open because of the valve timing overlap.

You should start over, first verify you are true TDC on #1 cyl (end of compression stroke), and the rotor is pointing at #1 terminal in the distributor cap. disconnect the vac lines to the distributor and plug them, start it and than check the timing with it idling at 800 rpm.

[dlb]

I decided to check the timing again after talking to the smog shop.
I get something in the range of 30-35* btdc, I was only able to adjust it down to 25*.
I went by the smog shop to check my reading, we got 20*.
A month before when I replaced the plugs, adjusted the valve clearance, and set the timing, it was 5* btdc & 13* btdc retarded.
I did replace the cap afterwords, some vacuum hoses, etc.
But none of this should have affected the timing.

if you are positive the base ignition timing was indeed 5* BTDC just a few weeks ago and you have not adjusted the timing since, there are a few possibilities i can think of.

first, check to make sure the advance mechanism in the distributor is not gummed up and sticking. this is relatively common due to the old grease in the dizzy getting dirty. the easy test is to remove the dizzy cap, grab the rotor, and turn it counter clockwise. it should have a small amount of spring-loaded play. if it does not move, or if it requires force to move it one way or the other, you must remove the dizzy, disassemble it, clean out the old grease, re-grease it, and reinstall the dizzy. not a bad job actually, only takes an hour or two. great step by step instructions in the FSM, too.

if your dizzy passes the test, turn the crank pulley clockwise until the mark on the pulley is at the '0' on the lower timing belt cover, remove the upper timing belt cover, and confirm that the cam pulley marks line up with the marks on the head. more info on this in the FSM too. if the marks don't line up, it's probably because the belt is worn/damaged, the tensioner is worn/damaged, or the crankshaft/woodruff key/crank pulley are worn/damaged and allowing the timing belt to slip. check those out and let us know what you find.

I tried to rotate it 180*, but than it wouldn't start, switched it back.

The #1 cylinder (front) was tdc (vacuum hose barely went in), and the distributor installed centered with marks aligned.
Since everything is connected with gears I don't understand how it could have changed the past month.

What am I missing?
How to I adjust it correctly? (do I have to "miss align" the distributor marks?

here is how i install a dizzy on a tercel. works great for me, done it many times.

https://tercel4wd.com/forums/viewtopic.php?f=4&t=7664#p56030

A month before when I replaced the plugs, adjusted the valve clearance, and set the timing, it was 5* btdc & 13* btdc retarded.

i think your terminology is incorrect here. 5* BTDC is the stock base ignition timing, and it should advance to 13* BTDC at idle when manifold vacuum is connected to the upper vac advance unit port. there is no component in tercels that retards ignition timing.

once you get this sorted out, i imagine the car should run much better. keep us posted.

[geoedb]

Thanks, in researching I did come up with some of these as possibilities

But the engine was rebuilt 30k ago, so it seems unlikely that it slipped. Although it could have been set wrong and the dizzy installed to match. After the rebuild when I checked the timing it was not advancing when I reinstalled the vacuum hose. So I bought a new vacuum advance valve and replaced it. I had trouble timing it, and my mechanic helped get it in place (we did not set #1 in tdc, he set the dizzy to match where the engine was).

So the smog tech had commented that there was no vacuum at the dizzy, and that I had a leak. Of course I had replaced 75% of the tubing during this process.

Since I had everything set early on, and the next day the idle speeds were all wack, I got to thinking. I had replaced hoses, and was checking a the emissions components. And there is no vacuum at the dizzy. And I though I was careful to replace one hose at a time. I should have taken a picture of the vacuum hoses before I started.

So it was time to check the vacuum line routing...................................................................

The VTV was hooked into the EGR. But still no vacuum at the dizzy. Switched the 2 hoses.

Damm, now the timing was about right, and I could adjust the tsp and idles to factory specs! I set the timing to 7* btdc (CA allows +/-3*) and 15* advanced.

Took it to the smog shop Friday. Tech measured 9* btdc, drat. He ran a full test, and it failed HC & NO at 15mph, and almost at 25mph too.

One problem solved, another uncovered. I need a new cat converter, and the VSV that's bad too is involved in the HC / NO too.

Before I started the work I was getting stalling as the engine warmed, plus the cold idle seemed to kick in as the engine warmed. The shop that rebuilt the carb 30K ago had trouble setting the base idle of 800rpm too, and I don't remember what he did to set it right (adjust the tps?). So I suspect that the vacuum lines may not have been right the whole time, but without having taken a picture I can't know for sure.

Having the forum has help where I lack training, experience & knowledge.

[irowiki]

How did you fix the stalling as the engine warmed, with the fast idle kicking in after it was warmed up some? Exactly what my california specced car does.

Could you take a picture of the emissions sticker under the hood for me?

[Petros]

your vac lines could be all messed up. do NOT assume that who ever worked on it befor you knew what they were doing, even if done by a repair shop. You do not need a picture, likely you have some misplaced anyway.

there is a thread on this fourm with vac line diagrams, or you can go to the FSM an look for your model (California emissions manual trans I would assume, if yours was not a california car than it would be federal). Trace each vacuum line from one end to the other, inspect for correct routing, cracks or damage, and proper connection. It does not take long, just do it systematicly. ONce that is done, if you still sustpect a vac leak check the intake manfold gasket (sometimes the manifold bolts work loose), and check each vac operated compnet, like the vac adavance. if the compente is bad it will act like a vac leak. set the timing back a bit.

Once that is done you might check the emissions again, you might pass without a new catalystic converter. I have heard you can remove the cat and soak it in soap and water, and than flush it out. It might remove contamination, if it works it will save you a bundle. If that is the last issue to resolve and there is nothing else to fix, than replace the cat.

[tercel4wdrules]

It seems to me like your chances of passing the ASM dyno test are higher if you have your base timing set around 4* BTDC. I had one of my cars run with advanced timing on the dyno test and HC & NOx were high. What were the other gas readings @ 15 MPH? Vacuum leaks can cause high HC & high NOx, so if you have a leaky vac advance diaphragm you may want to plug the lines to the distributor, but make sure they don't look tampered and hooked up properly. It sounds like your vacuum routing might not be correct if you don't have vacuum at the lower hose that connects to the dist vac advance. I would double check and make sure all the hoses are routed properly, the EGR is working, no vac leaks and perhaps check the operation of the TVSV.

[ARCHINSTL]

Geez, but I am glad I don't live in CA!
Well, at least as far as having ooold vehicles goes...
Tom M.

[dlb]

i find the hardest part of getting the vac hoses routed correctly is following the tangle of metal pipes between the valve cover and carb. what i do now to make that easier is unplug the hoses at both the TVSV end and the choke breaker B/carb ports/vac advance unit and blow into them at the TVSV end. i can then feel the air coming out at the other end and confirm i've got them going to the right places.