1985 FJ60 with stock 2F motor. Need help with motor. Hard start whether cold or warm. (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

The seatbelt warning light is powered by wiring coming off the ignition switch. Re check the white wire coming off the fusible links going to the alternator. check the fusible links again, and check the wires from alternator to ignition switch.

Note that power to the seatbelt warning light and relay would be downstream of the igniton and would have no affect on the ignition switch or motor but is an indication that the ignition is not getting the 12v it needs. Look at the schematics on 84-90 body and chassis fsm at the back pg 715, 717.

Also the hiccups caused by an engine wanting to stall (ie could be anything or not related to electrical) could be sending little to no voltage to the ignition on a momentary basis causing the light to flicker.

The fact that the motor isn't idling could be a vacuum leak or lack of fuel. Listen for vacuum leaks around the carb. Spray carb cleaner around the base of the carb and around the intake where it connects to the cylinder head (do this before things get too warm). Make sure the fuel is 1/2 in the carb window. do this by looking with a flash light and shaking the truck to see the fuel move. Take off the top of the air cleaner and look down the carb and actuate the linkage on the back of the carb by hand to insure that a good squirt of fuel is going down the venturi.

Check for spark at each plug wire. Do this by removing the plug wire and put a screwdriver into the end of it. (should be many youtube videos on this) Turn the motor (but dont start it) and watch for spark to jump to ground on top of the motor . Hold it about 1/8th and inch from ground .. do this with low light conditions so you can see spark. obviously do not touch the metal part of the screwdriver while doing this and where leather gloves for safety.
Newbie here and will get around to introducing myself and LC later. I noticed in the video when the seatbelt light comes on that the voltmeter gauge seems to jump up to what would be the normal output range. Hopefully I am posting this correctly since this is my first time.
 
The seatbelt warning light is powered by wiring coming off the ignition switch. Re check the white wire coming off the fusible links going to the alternator. check the fusible links again, and check the wires from alternator to ignition switch.

Note that power to the seatbelt warning light and relay would be downstream of the igniton and would have no affect on the ignition switch or motor but is an indication that the ignition is not getting the 12v it needs. Look at the schematics on 84-90 body and chassis fsm at the back pg 715, 717.

Also the hiccups caused by an engine wanting to stall (ie could be anything or not related to electrical) could be sending little to no voltage to the ignition on a momentary basis causing the light to flicker.

The fact that the motor isn't idling could be a vacuum leak or lack of fuel. Listen for vacuum leaks around the carb. Spray carb cleaner around the base of the carb and around the intake where it connects to the cylinder head (do this before things get too warm). Make sure the fuel is 1/2 in the carb window. do this by looking with a flash light and shaking the truck to see the fuel move. Take off the top of the air cleaner and look down the carb and actuate the linkage on the back of the carb by hand to insure that a good squirt of fuel is going down the venturi.

Check for spark at each plug wire. Do this by removing the plug wire and put a screwdriver into the end of it. (should be many youtube videos on this) Turn the motor (but dont start it) and watch for spark to jump to ground on top of the motor . Hold it about 1/8th and inch from ground .. do this with low light conditions so you can see spark. obviously do not touch the metal part of the screwdriver while doing this and where leather gloves for safety.

Hello G-man,

Thanks again for the reply! I will use this as a todo list and check off each hopefully this weekend! This is truly frustrating and I need to get tot he bottom of this.
 
Newbie here and will get around to introducing myself and LC later. I noticed in the video when the seatbelt light comes on that the voltmeter gauge seems to jump up to what would be the normal output range. Hopefully I am posting this correctly since this is my first time.
Looking at the video again. Looks like you are right! the seatbelt light comes on at the same time the voltage meter goes to a more normal position(12.5 to 13.5) So I'm guessing at that time something electrical is now making contact...a ground, a relay warmed up? ignition relay?, and the idle smoothed out. again points to something electrical between the alternator and the ignition.
 
Looking at the video again. Looks like you are right! the seatbelt light comes on at the same time the voltage meter goes to a more normal position(12.5 to 13.5) So I'm guessing at that time something electrical is now making contact...a ground, a relay warmed up? ignition relay?, and the idle smoothed out. again points to something electrical between the alternator and the ignition.

My thoughts exactly. Something electrical is getting triggered somehow and at some given moment to where it kicks the system into normal running mode. I'm trying to decipher the wiring diagram in the FSM.
 
Not that the factory voltmeter is the greatest gage but yours says to me your alternator isn’t charging. Can you take a picture of your instrument cluster with the key on but the engine off?

Hello Seth,

Here is the image of the ignition switched to the "on" position, but the engine not running.

FJ60 Gauge.jpg
 
ok. So the good thing is your "Charge" light looks to be on. Next, when the key is on but engine not running pop the hood and read the volatage with your voltmeter at the battery (pos to neg terminals).

Your in dash meter is looking like about 11 volts

when the truck starts does the charge light go out immediately or does it flicker or does it stay on?
 
ok. So the good thing is your "Charge" light looks to be on. Next, when the key is on but engine not running pop the hood and read the volatage with your voltmeter at the battery (pos to neg terminals).

Your in dash meter is looking like about 11 volts

when the truck starts does the charge light go out immediately or does it flicker or does it stay on?


It goes out immediately
 
Well, I think I found a link...to what, I don't know, but today when I started her up, the charge light did NOT come on and it stumbled like she does. I turned her off and turned her on again and the charge light turned on and she started up with no stumble. I did this about 3 or 4 times and every time the charge light did NOT come on on start up she stumbled. Every time the charge light DID come on on start up, she started without a problem. I traced the white alternator wire all the way to the fire wall and there didn't seem to be any loose connections, either at the back of the alternator or at the fusible links. I shook the both the alternator wires and the fusible link wires while she was idling and she didn't stumble or anything. Just ran and idled smoothly. Is this a sign that the alternator is going bad?
 
remove the cover from the voltage regulator and check the connections there to make sure they are tight and no wires burned. A faulty voltage regulator can drop your voltage. You can replace the regulator. they are available from Toyota. The regulator is the rectangular box mounted on the alternator. Very easy to replace. Two screws to remove the cover, three screws to remove the wires. When mine failed the voltage dropped but I don't recall it going up and down.
 
remove the cover from the voltage regulator and check the connections there to make sure they are tight and no wires burned. A faulty voltage regulator can drop your voltage. You can replace the regulator. they are available from Toyota. The regulator is the rectangular box mounted on the alternator. Very easy to replace. Two screws to remove the cover, three screws to remove the wires. When mine failed the voltage dropped but I don't recall it going up and down.

On the list of things to check. Seems the list just gets longer and longer! But I’m grateful for every bit of insight and advice I get!
 
I bought an aftermarket "Quality-built" (brand) 14340 off of Amazon 6/2019 It's held up well so far. At the time it was only $26.91, now they show 75.51. You have to pull your pulley off and take their double pulley off and put yours on. You'll want an impact wrench for this, and you need to take the alternator off to get your impact wrench on the pulley. And as i recall I borrowed a thin walled 24mm socket (read not impact) to get their pulley off.
 
Yep. You want the charge light to light up with key on engine not running and once the engine starts that light should go off. If the charge light does not come on with the key then when you start the truck you are just running off the battery. Sounds to me like your rough running is occurring because you are running off the battery and the battery is low on charge. These trucks don’t need much juice to run but an unchanging battery will only last so long.

so very likely your alternator is charging intermittently and likely just enough so you think things are ok. Could be a bad rebuild or a faulty voltage regulator etc. I got one off Rockauto for about $50 and It’s been charging properly so far.

EB101DF4-4393-4C31-A494-FF40657C1528.jpeg
 
I bought an aftermarket "Quality-built" (brand) 14340 off of Amazon 6/2019 It's held up well so far. At the time it was only $26.91, now they show 75.51. You have to pull your pulley off and take their double pulley off and put yours on. You'll want an impact wrench for this, and you need to take the alternator off to get your impact wrench on the pulley. And as i recall I borrowed a thin walled 24mm socket (read not impact) to get their pulley off.

So all the connectors are the same as well?
 
Yep. You want the charge light to light up with key on engine not running and once the engine starts that light should go off. If the charge light does not come on with the key then when you start the truck you are just running off the battery. Sounds to me like your rough running is occurring because you are running off the battery and the battery is low on charge. These trucks don’t need much juice to run but an unchanging battery will only last so long.

so very likely your alternator is charging intermittently and likely just enough so you think things are ok. Could be a bad rebuild or a faulty voltage regulator etc. I got one off Rockauto for about $50 and It’s been charging properly so far.

View attachment 2278228

Hello Seth,

I went on the Rock Auto website and noticed that that particular Alternator as an internal regulator. Will it matter that I'm going from an external voltage regulator to an internal? In othe words, will the wiring (plugs) be different from the ones in my image? Maybe my 85 uses a different alternator than an 86?
 
It doesn’t matter. There is a threaded post for the power connection to the battery and there is a connector that connects to the wires. The only thing I had to do was swap my single pulley from the old alternator to the new. The new came with a double pulley.


ABC030E4-8583-4C84-AE09-A6EFF140AB82.jpeg
 
Before you buy another alternator just make sure the wires between the alternator and battery are all good. Your intermittent charge light makes me think alternator but I’d pull the wires off the battery and alternator first and give them a real good look.
 
Also if the light doesn’t come on and the truck starts and runs rough try giving the case of the alternator a couple of taps with a hammer and see if the engine smoothes out. If that’s what happens then for sure it’s an alternator issue
 

Users who are viewing this thread

Back
Top Bottom