Idle and ignition timing help

[FJ60BigLou]

This is my 85 60. Love the truck. Kinda new to under the hood. Did a vacuum gauge test and indicates leak and/or ignition timing issue.

Took to mechanic for exhaust weld. He liked the truck he asked if there was anything else he could do. Told him of vac test and he said he look into it. Reported not finding any leaks. Not sure how hard he looked.

I did propane and smoke test (cigar) and couldn't find anything, though not sure I was doing it correctly. Shying away from carb cleaner test because of the mess and afraid of spark setting the truck on fire.
Have timing light and watched nearly every YouTube video out there. Think I'm ready.

Here is the concern: starting idle around 650-700. As it warms up (5-10 minutes) idle floats to about 1000-1100 and sits there even while sitting at a stop after driving. I don't want to adjust timing while idle is floating up.

Am I correct on not adjusting timing while idle is high?
Where do I look next for floating idle?
I have FSMs. Keep in mind I am a noobie.
Thanks for any and all help!!!

 

[Output Shaft]

I wouldn't worry too much about timing right now. If it's set correctly once, it'll (pretty much) stay set for the life of the engine. The 2F uses timing gears. There's no way really it can get out of adjustment on its own.

But it's a good thing to check anyway. Put it on your to-do list.

Don't check it above 900 rpm or so as you'll get an incorrect reading.

Does your choke work?
Are you using it at startup?

The correct way to start the 2F is with the choke pulled out all the way when the engine is cold.

Once it starts, the idle should hover around 1000-1200 RPM or so as its warming up. Soon thereafter the idle will start to rise as the oil starts circulating and the engine begins to warm.

Then the choke knob is incrementally pushed in to keep the idle near 1000 rpm or so.

Then after a little while, the choke knob can be pushed all the way in and the engine should idle at its set idle speed... Whatever it is you set it at. The spec is 650, but the engine actually is happier idling a little higher than that.

If your engine is idling at 1000 when warm with the choke pushed in, you need to adjust the idle speed screw on the carb. You just need a screwdriver. How to do that is described in the FSM.

 

[FJ60BigLou]

I'll definitely wait on timing. Vac test still is a concern. Just got back from a drive. Noticed right before I got in to leave there was a foul smell. Any thoughts on smell? Any suggestions for chasing vac leak?

 

[Landpimp]

Question

Whats the vacuum guage reading? Is it solid or does it bounce around?

Any chance the AC is on when the RPM's increase?

When you pop the gas cap, does it go whoosh?

 

[FJ60BigLou]

The gas cap does not go woosh when removed. AC is not on. Vac gauge does not bounce. First pic when started and idle at 650 (just over 11). Second pic (w finger - just over 13) after idle floats and holds at 1000. Very slow idle increase (2-4 minutes).

 

[FJ60BigLou]

Vac gauge connected to brake booster vacuum line.

 

[Output Shaft]

If you're at sea level, the vacuum levels are reading low. At sea level it should be near 19-20.

If you're up in the mountains, then those readings would be normal-ish.

Though 11 is pretty low even at 7000 ft.

 

[FJ60BigLou]

Okay. I am 500'. Where do I start?

 

[FJ60BigLou]

Is there a way to check if intake manifold gasket is leaking? Symptom?

 

[Output Shaft]

Check for vacuum leaks at the easiest places first.

Check every vacuum hose.
PCV hoses tight.
Test the plastic VCV valve that is clipped to the underside of the air cleaner on the passenger's side. If you apply a vacuum to port S it should hold vacuum.

One way to try to see if there is a vac leak around the manifold is to spray carb cleaner at the sealing edges. The engine wont catch fire. And carb cleaner won't leave an oily mess. I've heard using propane squirted through a small hose can work. I've never tried it.

 

[FJ40Jim]

The vac gage isn't telling anything we don't already know, i.e. engine runs like poo, therefore shows low vacuum.

What happens when idle speed screw is adjusted to bring idle down to desired idle speed?

 

[FJ60BigLou]

The vac gage isn't telling anything we don't already know, i.e. engine runs like poo, therefore shows low vacuum.

What happens when idle speed screw is adjusted to bring idle down to desired idle speed?

I'll try it tomorrow and let you know.

 

[FJ60BigLou]

The vac gage isn't telling anything we don't already know, i.e. engine runs like poo, therefore shows low vacuum.

What happens when idle speed screw is adjusted to bring idle down to desired idle speed?

Does the starting out at 650 and floating up to 1000 in 2 to 4 min. Tell you anything?

 

[FJ40Jim]

It tells us the warm idle speed needs adjusted down.

 

[FJ60BigLou]

It tells us the warm idle speed needs adjusted down.

Jim, though very excited to do this, I must admit to having no experience with adjusting idle. I thought I would begin by immersing myself in FSM and Haynes, but do you have any tips so that I don't made a bad situation worse?

 

[FJ40Jim]

Turn the idle speed screw to raise or lower idle speed as desired. It's the screw on the back of the carb that is hard to get to. The easy screw is the choke idle speed, don't be fooled by it's temptingly accessible slot.

 

[2mbb]

Here is a schematic from the FSM. The other posters are talking about adjusting the idle speed screw. At some point it may be helpful to also adjust the idle mixture screw (along with the idle speed screw). But take it step by step for now. As Jim say's, the idle speed screw is really hard to see. I have to rest my chin on the left fender and look through all the linkage to see it. Access with a long screw driver from above isn't so bad, once you have "eyes on it".

I noticed in one of your pictures above that it looks like you have a non-standard air cleaner/air intake for a US FJ60. Is the engine stock (ie. does it have all of it's original emissions equipment, etc.)?

 

[Landpimp]

also see a sheet metal screw head, that is probably stuck in some of the vacuum line end or port, so part of the emissions stuff may be missing, which may be causing your issue

I noticed in one of your pictures above that it looks like you have a non-standard air cleaner/air intake for a US FJ60. Is the engine stock (ie. does it have all of it's original emissions equipment, etc.)?


View attachment 1176440

 

[Jcos]

Jim, though very excited to do this, I must admit to having no experience with adjusting idle. I thought I would begin by immersing myself in FSM and Haynes, but do you have any tips so that I don't made a bad situation worse?

One tip especially if unsure, take careful note of where adjusting screws are BEFORE you start, so you can return them if it is not helping. You will know it is not helping when it is running much worse than before you started.
I would also determine that there is no leaking where intake manifold attaches to engine or carb to intake manifold (carb cleaner is good, you can also grab hold of carb & try turning & rocking to detect any looseness). Also carefully inspect all vacuum hoses for cracks & that all connections are tight & not allowing any air in.
These are usual first steps the manual will tell you to make to be absolutely sure all else is well with mechanical aspects & ignition system before attempting carb tuning.