FJ40 won't start when hot (2 Viewers)

[FJ4006791]

Hey there all,

Problem: I have a 1976 FJ40, bone stack near as I can tell. It starts up no problem, choke it, 4 to 6 pumps on the gas turn the key. Runs well, seems like it will run all day. When I turn it off and let it sit for a few minutes, I can't get it started for probably 45 minutes or so.

From reading around it seems to me like either vapor lock or stuck float.

Pertinent Info: New distributor - Trollhole
Rebuilt carburetor - done by a local carburetor guy
Valve job last year few hundred miles since
When I turn the engine off I can see gasoline bubbling in the sight glass

Due to the reputation of the carb guy and the fact that the gasoline seems to be boiling I am leaning towards vapor lock.

I am looking for suggestions on how to proceed or what else I may be missing.

Other pertinent (or not) info. - One side of the carb looks very clean the other not so much.
There are some danglling, cut, capped and bent hoses that i have pictured below


Thanks

Mark

 

[adistler1]

Is your carb cooling fan turning on and shutting off?

 

[FJ4006791]

No carb fan

Also forgot to mention there is a riser underneath the carb

 

[Tancruiser]

Try some ethenol free gas the gas they are selling us boils at a much lower temp.

 

[Splangy]

These things can be tricky to start after they sit while hot because fuel can siphon out of the idle circuit into the manifold causing an extremely rich condition. Next time it happens, put your gas pedal to the floor but DO NOT PUMP THE PEDAL. Then try to start it and obviously left your foot off the pedal on end it does.

 

[sggoat]

This was a daily prob on my 77 a few yrs ago-exactly as you describe. I installed a cooling fan--only minimal help. Reinstalled the mani heat shield--still didn't stop the prob--fuel was boiling in the carb bowl--you could hear it.
Finally installed a set of headers when I had to replace the head--no prob since--engine bay is cool as can be--no vap lock, no boiling, no hard starting--something to consider--

 

[FJ4006791]

Thanks Splangy, I will give that a try, in my driveway of course!

SGGoat, I'll look into that

Tancruiser, aside from the small cans they sell for small power equipment, where would i find ethanol free gasoline.

 

[skidplate]

My hot start routine is pedal to floor DON'T PUMP, as stated before, and turn the key.

 

[hooter]

Tancruiser, aside from the small cans they sell for small power equipment, where would i find ethanol free gasoline.

Check locally owned gas companies.

We have on here that sells no ethanol. Not cheap in the short run....

 

[Tancruiser]

Where I live it's about 50 cents per gallon more .

 

[Pin_Head]

Yes. Hold the pedal to the floor and crank it. Let up when it starts. That is the hot start drill.

 

[Steamer]

Ethanol-free gas stations in the U.S. and Canada

 

[Rat Rod Rusty]

I too have had this on going issue and have another couple related questions for you all.

1. The engine seem harder to crank over when it's hot like this. I.e. The starter actually sounds like it's struggling to turn. Why would this happen?
2. My temp typically runs 160-170 but during these hot summer days it goes to 190 and when I shut the motor off the temp continues to climb 195+. Eventually, everything cools and once again the motor turns over easily. Is this too hot ? I just replaced one head gasket...not wanting to do that again for a long time.

 

[68ToyCruiser]

I'm new on this forum and with FJ's, but if this happens to me I will consider a switched electric fuel pump, with a pressure regulator, insulate the fuel lines where possible with heat insulating webbing. The riser on the carb is a great idea if it is made of a material that will dissipate heat. Route all lines away from exhaust lines or manifold. A manifold heat shield might work. Lastly. I would try converting to electronic ignition and a high output coil.
This is what I leaned from my flat head Merc when it was vapor locking. I just did a 400 mile trip in 90+ degrees and it never stalled on me once.
Bob

 

[Splangy]

I'm new on this forum and with FJ's, but if this happens to me I will consider a switched electric fuel pump, with a pressure regulator, insulate the fuel lines where possible with heat insulating webbing. The riser on the carb is a great idea if it is made of a material that will dissipate heat. Route all lines away from exhaust lines or manifold. A manifold heat shield might work. Lastly. I would try converting to electronic ignition and a high output coil.
This is what I leaned from my flat head Merc when it was vapor locking. I just did a 400 mile trip in 90+ degrees and it never stalled on me once.
Bob

This isn't a vapor lock issue.

 

[Pin_Head]

It is not an FJ and it is not vapor lock, especially on a 76 that has a fuel return line.

 

[1911]

I too have had this on going issue and have another couple related questions for you all.

1. The engine seem harder to crank over when it's hot like this. I.e. The starter actually sounds like it's struggling to turn. Why would this happen?

Weak battery, corroded battery cables, poor (corroded) connection(s) on starter/battery cables, degraded grounding (bad connections or cables).

2. My temp typically runs 160-170 but during these hot summer days it goes to 190 and when I shut the motor off the temp continues to climb 195+. Eventually, everything cools and once again the motor turns over easily. Is this too hot ?

No.

 

[68ToyCruiser]

Vapor lock or not, the problems posted are identical to the problems I was having with my flattie. I converted my 6 volt system to a 12 volt system and went with an alternator and electronic ignition with a Flame Thrower coil. I tried to eliminate any hot surfaces near the gas lines and the starter, so I wrapped my headers and the starter with thick insulation wrap. On my trip up the Sierras to Sutter Creek in nrar 100 degree weather, the Merc hit the hot mark on the temp gauge but it never boiled over, and it never stalled. When I'd stop, the engine would start right up.
On my 56 Chevies with a 265, and a 327, I routed my gas lines and brake lines away from my exhaust system to keep the gas and brake flujid from overheating. I also bought intake manifold gaskets that would close the ports meant to warm up the carbureted gas on cold morning starts.

 

[68ToyCruiser]

It is not an FJ and it is not vapor lock, especially on a 76 that has a fuel return line.

Sorry Pin_head, but I thought Mark, the ps, said he had a 76 FJ, and that he suspected vapor lock.
Bob

 

[Pin_Head]

He said it is a FJ40.
An FJ is an FJ Cruiser, which is not a landcruiser.