Carb trouble

[76classic]

I understand your frustration...

But, to be clear, you asked for suggestions/help...

You are wasting people's time when you don't follow instructions or answer even basic questions...

Good luck.

You're right. I apologize.
I tested pump on pinheads #39 suggestion. The system should be clean. New rubber between all connections. Still a lot of metal in system. New tank. New filter which sits between tank and pump. No load on motor at 2000 rpms when fuel in window drops below window and then comes back up. Clean inside inlet and outlet connections. New fuel pump.
Again, sorry about my lack of answering questions. Just really frustrated at this one.

 

[76classic]

Good stuff in the above posts..thought I would throw this in the mix..There are two adjustments on the float, one for fuel bowl level and one that dictates how far the needle is allowed to open from it's seat when the float is down. Perhaps the second adjustment is too tight...

Thanks for that. I will ask to carb guy to check both.

 

[Solace in Solitude]

You're right. I apologize.
I tested pump on pinheads #39 suggestion. The system should be clean. New rubber between all connections. Still a lot of metal in system. New tank. New filter which sits between tank and pump. No load on motor at 2000 rpms when fuel in window drops below window and then comes back up. Clean inside inlet and outlet connections. New fuel pump.
Again, sorry about my lack of answering questions. Just really frustrated at this one.

Keep in mind... The hard lines, along the passenger side frame rail, are the lowest point in the fuel delivery system.

They are prone to accumulating water and crud... Especially after 40 years... If you haven't cleaned them, it would behoove you to take a few minutes and disconnect both ends and blow them out with compressed air... You may even need to shoot some cleaner thru them... I used carb cleaner... Then blow them out and reconnect them.

But... If this is your problem, I would also expect to see crud in the new fuel filter.

I think you have an intermittent fuel delivery problem.

Your fuel pump is working... According to your @Pin_Head test... But, have you pulled the fuel pump and checked the arm that the cam "works"?

Perhaps, the arm is damaged and is "slipping", at higher rpms...

Good luck.

 

[76classic]

Keep in mind... The hard lines, along the passenger side frame rail, are the lowest point in the fuel delivery system.

They are prone to accumulating water and crud... Especially after 40 years... If you haven't cleaned them, it would behoove you to take a few minutes and disconnect both ends and blow them out with compressed air... You may even need to shoot some cleaner thru them... I used carb cleaner... Then blow them out and reconnect them.

But... If this is your problem, I would also expect to see crud in the new fuel filter.

I think you have an intermittent fuel delivery problem.

Your fuel pump is working... According to your @Pin_Head test... But, have you pulled the fuel pump and checked the arm that the cam "works"?

Perhaps, the arm is damaged and is "slipping", at higher rpms...

Good luck.

I've blow out all the steel lines including those that you indicated. The fuel pump is literally 5 days old so I am not suspect of that.
The bowl in the card fills up but goes too low before filling back up. I will have my card guy go over the two adjustments that mwebfj60 mentioned and report back.

 

[Pin_Head]

If you have a "screw top" fuel pump installed with a phenolic block spacer it will not pump enough fuel.

 

[76classic]

Old pump and new pump. They look the same.

 

[76classic]

Old pump and new pump. They look the same. View attachment 1459376 View attachment 1459378

No spacer. Just gasket that came with the pump.

 

[Pin_Head]

Chances are that the inlet is clogged. Take the cop cover off, clean out the inlet, check the float level settings and try again.

 

[76classic]

Chances are that the inlet is clogged. Take the cop cover off, clean out the inlet, check the float level settings and try again.

Will do. Thank you. I will update as soon as complete.

 

[76classic]

Ok, heres the update. Changed the fuel filter for the fun of it before i went to my carb guy. Noticed a couple small metal curved chunks of metal in both new and old filter. Looks like my original steel lines must be de-laminating. Gonna replace EVERY FUEL LINE, both feed and return. Clean out the carb, flush the tank, and install another filter. Any suggestions on obtaining pre made fuel lines, or am I gonna have to bend them myself?

 

[thebigredrocker]

Here's another option. Disconnect hardlines. Run small diameter wire (welding wire) through hardline, then pull some Kevlar fishing line through. Hook up a gun bore brush to the kevlar line and pull it through. Spray carb cleaner in line, blow out with air, run bore brush through again.

 

[76classic]

Here's another option. Disconnect hardlines. Run small diameter wire (welding wire) through hardline, then pull some Kevlar fishing line through. Hook up a gun bore brush to the kevlar line and pull it through. Spray carb cleaner in line, blow out with air, run bore brush through again.

Thank you for the suggestion. If the lines are delaminating though, I'm wondering if that method would just be considered a patch, so to speak.

 

[76classic]

Chances are that the inlet is clogged. Take the cop cover off, clean out the inlet, check the float level settings and try again.

Removed top of carb last night. Checked inlet, outlet, needle valve port. All were clean. Adjusted float. Same problem. Gonna drain tank again and give it a flushing out. If that doesn't work I'm out of options.

 

[thebigredrocker]

Dang it. You could have something in your tank that shouldn't be there.

Worst case scenario, you could pull your passenger seat, tank cover, sending unit. If you have sn iPhone, the camera and flash will fit in the sender hole just enough to take pictures of the tank insides. I've read stories of something such as a leaf mysteriously getting sucked up to the pickup tube. Then when the vehicle shuts down the leaf floats away only to be sucked up again when the vehicle is re-started. It's a hail mary. If it's a leaf sized object it won't be sucked from the tank when you pull the drain bolt.

 

[thebigredrocker]

Removed top of carb last night. Checked inlet, outlet, needle valve port. All were clean. Adjusted float. Same problem. Gonna drain tank again and give it a flushing out. If that doesn't work I'm out of options.

Good stuff in the above posts..thought I would throw this in the mix..There are two adjustments on the float, one for fuel bowl level and one that dictates how far the needle is allowed to open from it's seat when the float is down. Perhaps the second adjustment is too tight...

Sounds like the you have the float tab that controls fuel level in your sight glass dialed in, but did you happen to check the two tabs on the float that control fuel flow?

 

[76classic]

Sounds like the you have the float tab that controls fuel level in your sight glass dialed in, but did you happen to check the two tabs on the float that control fuel flow?

Oh my gosh, I forgot all about that suggestion. I will open her up again and check that. Having trouble finding any specs on the setting for that.

 

[mwebfj60]

It's 1.1mm. Gently lift the float and it's the gap between the top of the needle and float tab...probably saying something you already know but there it is.

 

[76classic]

It's 1.1mm. Gently lift the float and it's the gap between the top of the needle and float tab...probably saying something you already know but there it is.

View attachment 1466150

View attachment 1466152

I had no idea about this. Thank you sooo much for your effort in this. Can't wait to check it. I will report back.

 

[thebigredrocker]

I don't know what the down side is if the float is able to drop too far. I guess it would just bang againt the bottom of your bowl. With the air horn removed you should be able to let it drop and see whether the needle gets outta the way enough for fuel to flow.

While you have it apart you might as well pull the needle and seat and blow compressed air in it again. Might not hurt to take a picture of your needle. I saw one in a Aisan carb that was goofy and probably the reason the carb got yanked. If you suspect it's a needle issue, do some more close inspection.

You'll solve this mystery and it will be something simple.

 

[76classic]

I don't know what the down side is if the float is able to drop too far. I guess it would just bang againt the bottom of your bowl. With the air horn removed you should be able to let it drop and see whether the needle gets outta the way enough for fuel to flow.

While you have it apart you might as well pull the needle and seat and blow compressed air in it again. Might not hurt to take a picture of your needle. I saw one in a Aisan carb that was goofy and probably the reason the carb got yanked. If you suspect it's a needle issue, do some more close inspection.

You'll solve this mystery and it will be something simple.

Blew it all out last night when I had it apart. Everything looked super clean. Needle valve has a rubber tip. I will attach a pic when I get it apart again.