Fuel Delivery Problems
Posted: Thu Apr 07, 2005 10:41 am
I got the '73 engine that hadn't run in ten years to run...for a while.
Then some other problems began to appear.
I had significant gas leaks in the left manifold boot joining the dual port manifold with the singe tube manifold.
Also I had a leak around the bottom of the immediate flange on which the fuel pump sits.
I determined a little top end maintenance was in order.
I removed the fuel pump and found a vertical crack in the intermediate flange along a mounting hole.
So I ordered a new flange, gaskets, and a new fuel pump (to have on hand in case the old one wouldn't work on assembly) from a VW supplier here in Indiana.
Also I replaced the dual port manifold to head gasket on each side and the rubber manifold boots.
I took the carb off the manifold and opened it up to make sure I didn't have a bunch of sediment and crap in the bowl which might lead to fuel problems, and cleaned it up.
I reassembled the carb with a new main gasket.
I made sure to check the maximum deck height on the fuel pump pushrod...right at 13 mm...just what it should be.
Turned the motor over by hand to make sure the fuel pump pushrod was moving up and down. Everything looked good.
Put everything back together.
Put the new fuel pump on, hooked all the lines up, timed the engine with a static light and tried it. Nothing.
Pulled the output line (to the carb) off the and turned the motor over with the starter to check to see if it was pumping.
Nada. Nothing.
Changed back to the old fuel pump.
Tried the same procedures. Nada.
I even tried several times to "prime" both fuel pumps by taking the line off the side of the carb coming from the output side of the pump and filling it with gas. Filled the carb bowl while I was at it.
Boom, it would run, but would then die after about 1 1/2 minutes.
Did this four times with the same result.
Apparently it was only running on fuel in the carb float bowl.
I've come to the conclusion I have fuel pumps which aren't working.
There is gas to the inlet side of the pumps, but no output.
My old pump is an angled model, The pushrod is a 4 1/4" rod.
The new fuel pump is an upright model and I have to loosen the manifolds to get it in and out.
This new pump has a lever end which is farther up in the body of the pump than the old one.
The old pump's lever protrudes just slightly below the bottom of the pump.
I don't think I have a long enough rod to actuate the new pump.
The part number on the box it came in says 113-127-025 C and it's from Brazil.
Neither pump has a number on the pump itself.
So I'm dead in the water right now.
Hope someone can offer some advice and guidance on how to resolve my problem.
Then some other problems began to appear.
I had significant gas leaks in the left manifold boot joining the dual port manifold with the singe tube manifold.
Also I had a leak around the bottom of the immediate flange on which the fuel pump sits.
I determined a little top end maintenance was in order.
I removed the fuel pump and found a vertical crack in the intermediate flange along a mounting hole.
So I ordered a new flange, gaskets, and a new fuel pump (to have on hand in case the old one wouldn't work on assembly) from a VW supplier here in Indiana.
Also I replaced the dual port manifold to head gasket on each side and the rubber manifold boots.
I took the carb off the manifold and opened it up to make sure I didn't have a bunch of sediment and crap in the bowl which might lead to fuel problems, and cleaned it up.
I reassembled the carb with a new main gasket.
I made sure to check the maximum deck height on the fuel pump pushrod...right at 13 mm...just what it should be.
Turned the motor over by hand to make sure the fuel pump pushrod was moving up and down. Everything looked good.
Put everything back together.
Put the new fuel pump on, hooked all the lines up, timed the engine with a static light and tried it. Nothing.
Pulled the output line (to the carb) off the and turned the motor over with the starter to check to see if it was pumping.
Nada. Nothing.
Changed back to the old fuel pump.
Tried the same procedures. Nada.
I even tried several times to "prime" both fuel pumps by taking the line off the side of the carb coming from the output side of the pump and filling it with gas. Filled the carb bowl while I was at it.
Boom, it would run, but would then die after about 1 1/2 minutes.
Did this four times with the same result.
Apparently it was only running on fuel in the carb float bowl.
I've come to the conclusion I have fuel pumps which aren't working.
There is gas to the inlet side of the pumps, but no output.
My old pump is an angled model, The pushrod is a 4 1/4" rod.
The new fuel pump is an upright model and I have to loosen the manifolds to get it in and out.
This new pump has a lever end which is farther up in the body of the pump than the old one.
The old pump's lever protrudes just slightly below the bottom of the pump.
I don't think I have a long enough rod to actuate the new pump.
The part number on the box it came in says 113-127-025 C and it's from Brazil.
Neither pump has a number on the pump itself.
So I'm dead in the water right now.
Hope someone can offer some advice and guidance on how to resolve my problem.