FJ40 won't start when hot (1 Viewer)

[FJ4006791]

So today I opened the hood to start planning my next step to trying to solve this hot start problem. I was going to try to wrap the fuel lines with some rubber hose or maybe try to cobble up some sort of heat shield. I started tracing the fuel lines to decide how to proceed and their routing seemed somewhat odd. Both lines run very close to both the engine block and the top radiator hose. The alternator is new to the vehicle so I was wondering if maybe the person who installed the new alternator inadvertently rerouted the lines incorrectly? Also both lines looked slightly crimped in the bend around the valve cover en route to the carburetor. As far as the mention of possible coil issues, I noticed a few dangling wires and was wondering if someone could guide me as to what is going on with these

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[Splangy]

It sounds like you have two separate issues. The fuel siphoning out of the bowl is somewhat normal on these old carbureted engines. It can be overcome by putting your foot the the floor when starting. I don't think that an attempt to insulate your fuel lines is going to help.

Your posts seem to indicate that your starter is getting heat soaked and cranking too slowly once it gets hot.

 

[oldschool4wheeling]

Welcome to mud

Your fuel lines are routed correctly.

 

[sggoat]

It sounds like you have two separate issues. The fuel siphoning out of the bowl is somewhat normal on these old carbureted engines. It can be overcome by putting your foot the the floor when starting. I don't think that an attempt to insulate your fuel lines is going to help.

Your posts seem to indicate that your starter is getting heat soaked and cranking too slowly once it gets hot.

Correct. The issue as I have found, is that old monster mass of metal called the exhaust manifold. Without a carb fan, or a carb heat shield, the heat rising up from this thing will boil away any fuel sitting in the float bowl after a 30 minute drive. insulating the fuel lines will do little to help.
If you drive the truck for the 30 minutes(get it up to op temp), then park and shut down, my guess is if you wait about 30 seconds, it will start right back up. You wait 5 minutes or more and the float bowl has pretty much vapor in it--the liquid fuel has evaporated. An electric parallel fuel pump may help--it will pump liquid back into the bowl without having to grind away with the starter.
(install some headers and all your problems with this disappear)

 

[FJ4006791]

Your posts seem to indicate that your starter is getting heat soaked and cranking too slowly once it gets hot.

Is there a solution to the heat soaked starter, or will headers solve that as well.

 

[Nomis]

Is there a solution to the heat soaked starter, or will headers solve that as well.

Starter should not be getting that hot as it on the opposite side of the block away from the exhaust. If it is just a weak starter, consider upgrading to a gear-reduction starter.

 

[Max.Powerzz]

Any other Solutions? I have had the exact same issue for years, I can drive it around but when it gets hot it won’t start for another hour. I have headers so that has not fixed the issue.

 

[jm599]

Any other Solutions? I have had the exact same issue for years, I can drive it around but when it gets hot it won’t start for another hour. I have headers so that has not fixed the issue.

Have been in same boat. Yesterday took a spark checker with me and when it wouldn’t start, (good fuel level in sight bowl) found no spark at the plugs!
Cool down,,, spark returns. This was with a Pertronix II.
just put points dizzy back in and running great, time will tell.

Have Read lots, this isn’t supposed to happen.
Connections were clean, including ground.

 

[77mustard40]

Someone say kinked fuel lines? Here’s mine. 77 with a 76 carb routed with a return line and I don’t have any heat related issues, although I occasionally have to turn a hot motor a few seconds longer to get it to fire. I usually don’t touch the pedal on hot starts. Headers & FJ60 big cap dizzy but otherwise stockish.

I did have some cooling issues going back in time and at that time I did seem to have more hot start issues but that was before I went back to a TEQ carb close to my vintage (bought the truck with a Holley). Once I had the cooling system ironed out and the AISIN installed I’ve been good.

 

[Pin_Head]

Any other Solutions? I have had the exact same issue for years, I can drive it around but when it gets hot it won’t start for another hour. I have headers so that has not fixed the issue.

Did you try the hot start routine? It is the same as for a flooded engine.

 

[bwalker16527]

Is there a solution to the heat soaked starter, or will headers solve that as well.

Heat shield for starter, higher gauge battery cables, and/or high torque mini starter all can help with heat soak.

 

[CaliFJ]

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

Ha ha. Pinhead is a forum guru. So, damn, my callsign is likely offensive. Maybe a moderator will add the 40 to me. But I just completed the Rubicon Trail in my rig, so I really don’t give two s***s what these old farts think!! I love and respect them, though!

 

[Terry Lindsey]

I too have a 76 FJ40 and experienced the same issues. My remedy was wiring a direct line push button start switch to the starter (GR starter). For some reason I wasn’t getting enough amps to the starter when it was hot and didn’t want to chase wires. Test me fix out by turning your ignition switch to on and then cross over the starter terminal to ground and see if it starts. If it does, it’s a cheap and quick fix.

 

[tls3601]

Sometimes I wonder if these hard start situations are more common for us with aftermarket exhaust headers? Versus the original exhaust manifold? The OEM exhaust manifold also seems to keep your floor boards cooler as well from what I have heard.

 

[jmylie]

I had a similar problem once ages ago with my 68 Mustang. It was an internal short in the battery. Cold start, not a problem. Drive around and then park for a bit and it would not restart until the battery cooled down. Last time I purchased a Sears Die Hard battery.

If it is vapor lock, just remove the fuel line from the fuel filter to relieve the vacuum. Reconnect and see if it starts. If it does, vapor lock may be the issue.

 

[Dizzy]

On models, particularly those with return lines, where might fuel vapor exit the carb bowl?

I have a Weber which exits the vapor to the charcoal canister via an orifice installed in a line, and so I know that an engineer must have recognized the need. However, on the Cruiser carb you get this situation where the float needle would be open, because the float is immersed in vapor and not floating, but the vapor can't escape because the only exit is under a body of liquid fuel. So as the fuel pump keeps feeding the bowl, the pressure here would be released out one of the carb's circuits, causing an abnormally rich condition, right? Or, is the fuel vapor released thru the open needle valve and thru the return line back to the tank?

 

[Pin_Head]

The fuel bowl has two brass vent tubes cut at a sharp angle that open into the top of the air horn.

 

[FJ4006791]

So my issue ending up being a weakened battery due to the never ending cranking and a bad battery ground wire and terminal.

 

[Aussie Alaskan]

So my issue ending up being a weakened battery due to the never ending cranking and a bad battery ground wire and terminal.

How did you problem solve to figure out the issues that caused your FJ40 to not start for 45 minutes after running hot? I'm having almost identical issues and I'm thinking it's a flooding issue, but holding the throttle down with no choke won't start my FJ40 for about 45 minutes after shutting off. My GR starter seems to turn the engine over fine, so I suspect the battery is good, and it sputters and tries to start but won't fire off for 45 minutes roughly.