Fuel Delivery Problems

ztnoo · Post by **ztnoo** » 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.

ztnoo · Post by **ztnoo** » Thu Apr 07, 2005 8:59 pm

Gentlemen,
Since I've had no particularly helpful responses today from the three Thing forums I review and post at occasionally, allow me the freedom to answer my own question, arrived at by a personal sense of pressure to perform for myself and the owner, logic, reason, questioning a local shop working on a Manx with a Porsche engine with fuel delivery problems, and lots and lots of trial and error and wrenching.
As Captain Spalding told me..... it's all about the process of discovery.
Holy Sheep DoDo, Batman.....today I discovered more than I ever imagined ....or wanted to know for that matter.
But I know it now, locked in stone, same as "front is front, and rear is rear".

Se você pensar você leu-o todo em thesamba.com, revê esta situação.
or.....
Wenn sie denken, haben sie es aller an thesamba.com, wiederholen diese situation gelesen.
(If you think you've read it all at thesamba.com, review this situation).
Either way.....pretty nutty.

Thought about the problem all day.
Had fuel to the pump, rod height correct, rod actuated when engine was cranked by hand, but no fuel to the carb.
No output from the pump.
??? What the hell is going on?
Calls to Mike Basso and the guy who sold me the pump in southern Indiana only raised more questions.
Different pumps, different rods (now I understand there is actually a third length, besides the 4" and 4 1/4" rods, caused by a factory screw up in machining the cases).
What works with what?
I got lots of real iffy and mushy answers.

But the more I thought about it, I knew I had to go get the pump (a mile away) and look at it, and really analyze the part.
Brought the damned thing home to my computer desk and fiddled with it.
Let's see.....what's the intake port and what's the output port?
I moved the lever with my thumb.
Huuummm......well I couldn't feel the difference on my carpenter's weathered fingers, so I put it to my face to sense which port did what.
Still no luck.
So I put my big fat tongue on the part and actuated the pump lever to determine what was what.
After several tries, I concluded which was the intake port on my new pump, and which was the output port to the carb.

OK.....so what's the problem?
Well.......uh.....duh..... the old pump's intake port was on the bottom, the output port on the top.
The new pump?...the intake was on the TOP, the output on the BOTTOM!
Eureka!
EXACTLY OPPOSITE of the original fuel pump ports!
No directions enclosed in the box, just the Brazilian pump.
Portuguese logic.....problaby mixed with lots of German engineering and production pressures.

Anyone ever read about this anywhere?
I sure haven't, and have heard no one discuss the matter.

A word to the wise and the rest of us struggling dumb asses....never assume anything......lay your hands on it and check it out.
That's what I had to do with the cv bolts on the '74 Thing.
If you just assume by reason what you observed before will be the same, there must be lots of Brazilian Portuguese speakers who are laughing their asses off on a daily basis at US VW parts buyers.

Anyway, the engine that remained unstarted for ten years ran tonight for thirty minutes without something else imploding.

Overall, it's been a pretty good day in Hoosierland.

ztnoo

Bucko · Post by **Bucko** » Sat Apr 09, 2005 12:59 pm

I wish I would have read this forum this morning as I would have been able to provide you with the answer you already found yourself. I did the exact same thing.

Brazilian pump right? They reverse the gas tank/carb connection.

sideshow · Post by **sideshow** » Sat Apr 09, 2005 1:09 pm

I test every pump by blowing into what I think is the inlet, if it flows it is the inlet. And if blowing into the outlet doesn't flow, it is the outlet. Sucking also works but on used pumps you may find gas.

The other method that works fairly well is looking for the "-->" arrow that is stamped into many pumps.

Bucko · Post by **Bucko** » Sun Apr 10, 2005 12:54 am

Better idea than mine; I always took the pump rod, and operated the fuel pumps arm. Then I felt each port for suction and/or air. I could tell which side was the inlet (gas tank connection) and which was the outlet (to carb). This is hard to do with just two hands!

ztnoo · Post by **ztnoo** » Sun Apr 10, 2005 2:53 am

Bucko,
The old pump was Brazilian. It was an angled model. I don't think you can make any assumptions based on where these parts are made. I'm told VW originally made about 7 or 8 different looking pumps...now they?re supposedly down to two that fit everything.
After my experience, I would say anyone replacing a pump should test it himself to determine inlet and outlet. This is something an experienced VW wrench would know, likely from an experience about like mine.
This novice didn't do that...just made my own assumptions it would be the same arrangement as what came off the engine.
I haven?t noted any directional arrows on the new pump, so testing is the only way to verify which port does what.
ztnoo

Bucko · Post by **Bucko** » Sun Apr 10, 2005 2:13 pm

My replacement was just the opposite than yours; I started out with a "VW" pump, and had to replace it with the "Brazilian" unit when I converted to an alternator, to clear the new stand needed for the alternator.

Since I did both (alternator and pump) at the same time, I was thinking I had a wire or two wrong in the alternator. It was only when I realized that the engine ran for a few minutes before it stalled (fuel in the carb bowl kept it running), that told me the alternator was good (alternator light went out in the speedo when the engine started), and the problem was lack of fuel (peeked down the carb and operated the accellerator). I too wondered if the pump rod was correct, although I was sure that it was, since the alternator style fuel pump uses the shorter pump rod.

ztnoo · Post by **ztnoo** » Mon Apr 11, 2005 2:42 am

Bucko
Just to add to the mystery and confusion concerning VW fuel pumps regardless of the country of manufacturing, the angled pump I removed (which I assume was for an alternator setup) used a 4 ¼? rod. I have a generator system, so one would have to believe they must have had an angled pump model somewhere along the line that functioned with the longer rod and not the 4? rod you discuss. I also understood these alternator compatible fuel pumps used 4? pushrods, but for what ever reason, the old pump had functioned just fine with the 4 ¼? rods
The historical mystery of VW fuel pumps continues?just remember to test any new pump for flow direction before installing. That will eliminate at least one variable in the fuel delivery equation.
ztnoo

Bucko · Post by **Bucko** » Tue Apr 12, 2005 1:13 pm

".....just remember to test any new pump for flow direction before installing. That will eliminate at least one variable in the fuel delivery equation. "

I'm "hip" to that!

I just burned my lower backside (bum) getting into the shower here at my German hotel, because I did not test "those waters" either!

ztnoo · Post by **ztnoo** » Wed Apr 13, 2005 3:50 am

Bucko,
That's a bummer about burning your bum!
Yikes!
What ya doin' in Germany?
Trying to find some German fuel pumps with the original inlet and exahust arrangement?

ztnoo

Bucko · Post by **Bucko** » Thu Apr 14, 2005 10:06 am

I'm an instructor for a telecommunications manufacturer (Siemens). We have a large contract that replaced 75 military bases with new Siemens central office switching equipment. I've been coming here about 4 times a year now since 1999. This may be my last year traveling to Germany, as the contract is running out.

I did find my type 181 here about two years ago; finally had it shipped to the states this year.

I do like it here in Germany, and will miss this place when the contract does expire. A beautiful place to visit.