Intermittent Cold Start Issues - Fj40 1972 Stock (1 Viewer)

[Cesarf13]

So Guys I LOVE my FJ40 but VERY frustrated with my Intermittent Startup issues - hope you can help.

A bit about my FJ40
- New Batery, Cables, Sparkplugs, Startup coil (Internal Resistor).
- Stock Carb (to my knowledge)
- Stock Distributor (to my knowledge)
- Has the Evaporative Emissions Control Device and is connected as described here ('72 FJ40 Emissions Control Device~Advice - https://forum.ih8mud.com/threads/72-fj40-emissions-control-device-advice.551434/)
- I use 89 Regular Gasoline

Here is my Startup ritual (this is what has given me best results over time):

If Cold (Has been sitting for over 8 hours):
- Pump Gas 2 times Slowly (in and out)
- Choke 1/2 way
- Crank: I hear the Carb Solenoid, Carb Window shows Gas (about 3/4 full), Engine turs (the whole thing shakes)
- if it Turns on (About 50% of times): Joy, then push choke back in as idle stabilizes
- If it doesn't turn on: Push choke in, Wait 5-7 mins, and try to turn on as if it was hot (See below). Usually turns on, if not,,, wait another 5, repeat.

If Hot (has been shut off for less than 8 hours):
- Crank - Starts every time, EVERY TIME.

Here some of my desperate attempts to fix the issue:

- Drained the whole Gas tank and filled with fresh new Gas. Maybe some old gas and water - no changes.
- Treated Carb and Gas with SeaFoam. A can on the Tank, A can on the Carb Throat - did get some good results in terms of accel response and a better idle.
- Desmoged the thing for a few weeks and seemed like it was behaving SO MUCH BETTER - Startup rate went up to average of 80% of times. But now is back to the same Intermittent Startup behavior.
Desmoged like this:
- Connected Distributor Diaphragm vacuum directly to top of the Intake Manifold
- Connected Carburetor Diaphragm to bottom of Carburetor (Port looking towards the left hand drive Drivers Fender)

- I have 2 more larger Vacuum hoses that I have not messed with:
- One going from Air intake to Top of Valve Cover.
- One going from Base of Carburetor to Engine Block on the Passenger Side.

What Am I doing wrong? Does my Fj40 hate me? - What Should I be checking? The thing runs Beautifully, supper Strong (if it turns on)...

Here What I've been thinking on doing:

- Rebuild carb.
- Desmog and Convert to Weber Carb.
- or?

What do you guys suggest? let me know if some pics would help? or?

 

[rkymtnflyfisher]

So you try to crank it (cold) and it doesn't start on the first try?


Give it about 3 seconds and try again, choke out, pedal down.

 

[rkymtnflyfisher]

Convert to Weber Carb.

Definitely not the answer.

 

[rkymtnflyfisher]

Checked your timing lately? Valves?

 

[Skreddy]

Have you checked the valves lately? Otherwise, try what rkymtn said above.

 

[B y r o n]

You're in Florida so might be you really don't need to use the choke. What happens if you just give the gas pedal a couple pumps and then try starting?

 

[Cesarf13]

Good stuff guys. Have never checked timing on the valves. Ordering valve cover gasket and give it a try on valve timing once gasket makes it here.

Will be following this guide

First valve adjustment on my 78 FJ40 ...

What a weird trip, finally found the BB (7 ½ degrees before TDC) in the flywheel window (bolt/cover long gone) and painted it so it would show up with the timing light. Still wasn’t sure where the TDC mark/line was. Warmed the engine up and pulled valve cover, etc. At this point I ran at low...

forum.ih8mud.com

In the meantime Will try:
- No choke, 2 pumps on Gas, turn on approach
And
- Pedal down, choke out and crank after a failed “by the book” cold start.

Cheers!

 

[Jdc1]

Good stuff guys. Have never checked timing on the valves. Ordering valve cover gasket and give it a try on valve timing once gasket makes it here.

Will be following this guide

First valve adjustment on my 78 FJ40 ...

What a weird trip, finally found the BB (7 ½ degrees before TDC) in the flywheel window (bolt/cover long gone) and painted it so it would show up with the timing light. Still wasn’t sure where the TDC mark/line was. Warmed the engine up and pulled valve cover, etc. At this point I ran at low...

forum.ih8mud.com

In the meantime Will try:
- No choke, 2 pumps on Gas, turn on approach
And
- Pedal down, choke out and crank after a failed “by the book” cold start.

Cheers!

Valve adjustment and engine timing are two different things. One thing that might help is installing a Pertronix in the distributor.

Make sure not to make a ton of changes at a time or it can get hard to diagnose. Make a change and start it up, then move onto the next.

 

[rkymtnflyfisher]

Make sure not to make a ton of changes at a time or it can get hard to diagnose. Make a change and start it up, then move onto the next

Solid.