WrencherJosh

I recently purchased a 1987 Toyota with 340000 miles for 300 dollars and replaced the engine. After putting everything together I tried starting it, long crank, no start. I replaced the carb, same thing. Finally I tried some brake clean in the carb, fires right up and runs fine afterward, turn it off, immediately try to start it, crank no start. Anyone have any ideas?

slow-mo

So after the engine starts with the brake cleaner, it will continue to run and operate normaly?



Specifically, what is your starting procedure? What do you do to start the engine?

WrencherJosh

Correct it runs great after it is started. I have the air filter pulled at the moment so i just squirt some brake clean into the carb and turn the engine over and it will start. I obviously have to rev a little until the truck is warm but once its warms it will sit and idle all day, but if I turn the truck off then try to start it again its just a long crank. I don't know if maybe I have a vacuum leak or what I'm stumped.

slow-mo

OK, let's try again.

Skipping the starting assistance of the brake cleaner, how do you go about starting the engine? Do you just open the door, sit down, press the clutch pedal down, then turn the key to crank the engine? Are you doing anything to the gas pedal prior to cranking over the engine?

WrencherJosh

Oh I got what you're asking, I press the pedal 3 times to prime with the key on then try to start it.

slow-mo

3 pumps should be enough to prime it, so you're doing that correctly.

Is there fuel in the middle of the sight glass of the carburetor?




Next thing would be to visually check to make sure fuel is squirting out of the jet in the primary barrel when you're priming the carburetor.

Do you know which is the primary and the secondary barrel?

Do you know which jet the fuel squirts out of?

WrencherJosh

The glass does keep prime/filled with gas. I don't know much about this carb but I can tell you that I can smell gas when I am turning it over.

slow-mo

Here's a pic of my carburetor. What is circled in red is the jet that the fuel comes out of when you pump the gas pedal. Of course in that pic the top Air Horn is off , but that jet is visible when looking down the barrel.

Check to make sure fuel is being squirted from that jet during the priming stage.

WrencherJosh

Fuel is coming out of the jet.

WrencherJosh

I just rechecked my thread and noticed I forgot to put "not" in that sentence.

Fuel is NOT coming out of the jet. Would buying an electric fuel pump be a sufficient fix?

superex87

If fuel is NOT coming out of that jet than the accelerator pump diaphragm is probably torn and needs to be replaced or the jet is clogged up with gunk. An idea for you to try is to hold the gas down around 30%-ish while cranking. This will cause fuel to be sucked from the main jet and it should start for you. But deffinatly fix the accelorator pump issue as it will make the engine stumble when accelerating if its not working.

WrencherJosh

Thank you! Although the 30% trick did not work, I'm almost positive you are correct. Under further investigation the accelerator pump was MISSING on my first carb, and I went ahead and ordered a rebuild kit so I can replace the diaphragm. I will keep you guys posted.

slow-mo

Since fuel is now not coming out of that jet, as was mentioned, your Accelerator Pump is not working.

The Accelerator Pump is mechanically actuated, whereas the Auxiliary Accelerator Pump (AAP) is vacuum controlled. As a FYI, the Accelerator Pump is the one on the lower right in my earlier picture. The Auxiliary Accelerator Pump is on the opposite side, top right with a bent metal vacuum port in the same picture.



However, I suspect you also have an additional fueling issue as well. Since you stated that after you do get it running, when you shut off the engine that you can't restart it. After getting the engine started then shut down, you should be able to start the engine without pumping the gas pedal.

Actually, let me first ask you a question before I go to far. When you did get the engine started, did you let the engine get up to operating temperature before you shut off the engine and tried to restart it?

WrencherJosh

Yes I allow it to get go operating temp before trying again.

slow-mo

With the engine at operating temperature, the engine should re-start without touching the gas pedal.

You may also have a malfunction in the Idle Cut Solenoid. In the earlier picture I posted, it the the electrical solenoid at the lower left of the picture. It has the green sheath. An electrical signal will signal it open or closed. The Idle Cut Solenoid allows or prevents fuel flowing through the slow fuel circuit.



In these two pictures, the fuel flows from the Primary Main Jet, through the Slow Jet, through the Fuel Cut Solenoid, then out through the Idle Port.







The factory service manual will tell you how to test that solenoid.

WrencherJosh

I have no owners manual, so I guess here's a few questions. Obviously its at the very least electrically powered. How does this valve work? My truck has no ecu (that I'm aware of) and I have no clue in volts needed to open and close this valve so I don't know where to begin to test the valve. The harness makes it difficult to get out without cutting it, so I can't remove and test that way. I'm at a loss... Maybe just start with the accelerator pump diaphragm and if it doesn't fix the problem move on from there?

WrencherJosh

Took a ohm meter to it, no broken lines so if its bad its because its stuck open or closed.

slow-mo

There is a PDF version of the factory service manual here on Yotatech. You'll have to search for it, though.


It is just a simple plunger type of solenoid. The ECM controls the on/off mechanism.


The end of the harness plugs into a sub-harness (I guess one could call it that) just below the carburetor. Follow the wires from the carburetor down to the conector, remove the connector, then follow the procedure in the service manual.


Absolutley, start with what you know, then go from there. I was speculating that you may have an additional issue, but start at the pump diaphragm.

WrencherJosh

When I get home ill search for the owners manual, but where can I expect to find the ecm?

slow-mo

It is behind the passenger side foot kick panel. Basically below the passenger dash speaker grill.