From three cylinders not getting fuel (2 Viewers)

[maine40]

Hi all, I have an early 1975 FJ40 with the 2f engine, cylinders 1-3 are acting like they aren’t getting fuel and when I pull the plugs they are bone dry whereas 4-6 are wet when I pull them. The engine will backfire if i use starting fluid but other than that it doesn’t even try to fire off. If anyone has any suggestions please let me know.

Thanks
- Noah

 

[RodrigzCrzr]

I would say do a compression test.

 

[MatthewMcD]

Are you sure it's not getting fuel? The cylinders aren't fed independently, so the fuel entering the intake manifold will be distributed to the cylinder with the open valve.

Have you checked your distributor to ensure you have spark on all 6 cylinders? Wet plugs could be caused by failure to ignite the fuel (rather than the other way around.)

 

[RodrigzCrzr]

Also make sure your distributor is in the correct way and not 180 off.

 

[charliemeyer007]

When was the last time it ran? How old is the gas you are trying to run it on? Pull all the plugs and check each wire and plug for good spark. Make sure the timing is correct and the valve lash is good. I would do a dry then wet compression test with some Marvels Mystery oil in each jug.

 

[Jonathan Hanson]

As someone suggested, I suspect it's the wet cylinders that are the problem; they're not firing and are allowing fuel to collect. It's highly unlikely fuel would not be reaching some cylinders.

 

[WildernessRimFab]

Have you checked the valve clearances?

 

[73FJ40]

Hi all, I have an early 1975 FJ40 with the 2f engine, cylinders 1-3 are acting like they aren’t getting fuel and when I pull the plugs they are bone dry whereas 4-6 are wet when I pull them. The engine will backfire if i use starting fluid but other than that it doesn’t even try to fire off. If anyone has any suggestions please let me know.

Thanks
- Noah

OEM carburetor and intake manifold?

 

[maine40]

When was the last time it ran? How old is the gas you are trying to run it on? Pull all the plugs and check each wire and plug for good spark. Make sure the timing is correct and the valve lash is good. I would do a dry then wet compression test with some Marvels Mystery oil in each jug.

As far as I know it last ran bout 20 years ago, I’ve got brand new gas in it, it’s got all new plugs, wires, new points, new rotor, new distributor cap, i did check to make sure the distributor was in the right way, I have checked compression and it seemed fairly good, I guess I’ve gotta check out my valves

 

[maine40]

OEM carburetor and intake manifold?

It has a Weber 38 carb, im unsure on if the intake manifold it OEM or not

 

[65swb45]

Header?

 

[MatthewMcD]

As far as I know it last ran bout 20 years ago, I’ve got brand new gas in it, it’s got all new plugs, wires, new points, new rotor, new distributor cap, i did check to make sure the distributor was in the right way, I have checked compression and it seemed fairly good, I guess I’ve gotta check out my valves

What are the compression numbers and have you verified spark on all 6 cylinders? (HF has an inexpensive inline spark checker, or you can pull and ground a spark plug to the chassis.)

Photos of the intake and distributor?

 

[45Dougal]

I'd pull the valve cover off and check everything is moving as it should. Quick and easy to tick off the list

 

[maine40]

I'd pull the valve cover off and check everything is moving as it should. Quick and easy to tick off the list

I did that, everything looked good and sounded as it should

 

[pb4ugo]

Check firing order and check spark on 4-6.
Next would be compression. Air, fuel, spark.

 

[maine40]

Check firing order and check spark on 4-6.
Next would be compression. Air, fuel, spark.

So I guess I’ve lost spark on all cylinders so I’ve gotta check wiring and see where it’s messed up

 

[MatthewMcD]

So I guess I’ve lost spark on all cylinders so I’ve gotta check wiring and see where it’s messed up

When I lost spark on every cylinder it was the post on the distributor grounding out. The nylon insulator disintegrated and caused the issue. It's a $5 part.
Review this thread for additional ideas: No Spark Troubleshooting - https://forum.ih8mud.com/threads/no-spark-troubleshooting.1331245/post-15449413

 

[bikersmurf]

Point gap? Dwell if you have a meter. Too loose = no spark. Too tight = no spark.

Wiring a points distributor so the engine so it’ll run isn’t very difficult. Although… I’ll not post it here on a public forum.

 

[maine40]

Point gap? Dwell if you have a meter. Too loose = no spark. Too tight = no spark.

Wiring a points distributor so the engine so it’ll run isn’t very difficult. Although… I’ll not post it here on a public forum.

I think that my points are too tight because they were at about .20 and I reset them to .18 so I’m going to set them back to .20 and see if that changes things

 

[vfrer]

Hopefully you meant .020. They should be .016 - .020" so if you are at .018" it should be good.