Broken Fuel Pump Flange

[Hula Hooped]

Long time lurker. First time poster. I own a 1970 Bremen Maxi Taxi Autostick with a 1600 upright in it. I recently replaced the fuel pump. (Left me stranded.) On diagnosing it, it wasn't pumping fuel. Once I removed the pump, the flange broke (common issue I hear.) So I bought a new (china junk) fuel pump and reinstalled with the busted flange.. I just put the broken piece on top of the piece suck in the block. Just like it came out.. The car ran fine for about 5 minutes, then started to bog down.. Like it wasn't getting fuel.. Here's the strange part, by repeatedly stomping on the gas pedal I managed to keep it (barely) running the mile or so home, (I switched feet several times, Prob took hundreds of "pumps" to get her home that one mile.) It was bogging, backfiring, etc. So, now should I suspect the (new china) fuel pump? Or do you think the broken flange is playing a role here? I also somehow suspect the Carb "accelerator pump" may be an issue.. It wasn't (an issue) before the fuel pump fried. What should I be looking at to diagnose her again? Thanks.

[kangaboy]

Gotta make sure the pump is shimmed appropriately to allow the correct stroke of the fuel pump push rod...especially with some random Chinese fuel pump that may or may not have any quality control.
With what you're describing, my initial though is clogged idle jet...especially with how your described the accelerator pump getting you home.
Pop the top off your carb and see if the bowl is full of fuel. Also, disconnect your hose from the fuel pump outlet and put it into an empty bottle. Turn the car over for a few seconds and make sure your getting adequate fuel (whatever that amount may be).
Also supply a picture of you engine so that we can have a look and see if there is anything glaringly obviously.
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-74 Standard - "CaliBug" 2084T, MS3X w/FI and Crank Fire
-76 Westy - "Gandalf"
-18 GTI SE

[Hula Hooped]

Thanks Kangaboy,
I measured the top of the push rod above the flange to be about a quarter of an inch before I installed it. (more lurking on here for that.) That measurement seemed acceptable to what I've read on here.
I did take a phone video of the fuel pump in action last night. (i work alone, and can't crank the key and be out back by the engine bay.) It seemed to be pumping "enough" fuel. Pretty decent "squirts" while cranking. Although (odd to me) is that if you leave the fuel hose below the level of the engine, it continues to pour out fuel. (Somehow I thought maybe it was blocked off until the pump came on.) But whatever on that.

I'd go with you on the "clogged something" aspect. Good call on pulling the top of the Carb off. I'll do that tomorrow and report back. If an "accelerator" pump fails, what happens? Is is "all of a sudden" the car just bogs down? I'm still wondering how I got the car to "grab a single rev or two and bog, grab and bog" for a mile also.. Way longer down the road than I thought I would get her. (I literally didn't give up, and Smashed the pedal over and over until she was in front of her garage.. I felt if I let off for a second, she was going to die, and not re start. I've recently had the tank out and boiled and cleaned, red coated etc.. New fuel lines the whole nine.. But something can always get in there I guess. I've never truly trusted this carb... I've had problems getting her to idle on her own. and generally fine tuning and dialing her in since I got her running. (She was down a worm hole for 30 years before we met.) Thanks again for the reply.. I'll keep diagnosing, and reporting in.
Also will take a pic of engine and post to this thread for you. But i'm guessing nothing glaring, because last weekend I took her out of town for about a 100 mile trip, (Sandusky OH Car show) and until the pump fried, (Or so I thought..) All was very well, and I was congratulating her on the whole trip.. Good VW, Good VW.....

[kangaboy]

Your continued story very similarly describes something that I experience in the past on a carb with a clogged jet. Just know, your fuel system can be clean as a whistle and still your carb can clog with crap that the air filter lets in. I had one of those cheap ass crappy chrome EMPI ones on a carb that cause me all my grief in the past. After getting the carb taken apart and cleaned, I stuck a nice stock '74 air cleaner on there and never looked back...I've learned my lesson.
Also, it was your accelerator pump that was keeping your motor running during your time of distress. You pumped the pedal and it shot stream of gas down the throat and kept it alive. Safe to assume this was the only way your motor was getting fuel, and in turn, kept it running. Further evidence that a jet is clogged.
_________________
-74 Standard - "CaliBug" 2084T, MS3X w/FI and Crank Fire
-76 Westy - "Gandalf"
-18 GTI SE

[Jimbug57]

There are 2 types of fuel pumps. They each require a different length push rod. Make sure you have the right length for the pump you're using.

The issue with the broken flange is that it is probably swollen and restricting the up/down movement of the push rod. There is a procedure for removing the broken end from the case so you can replace the flange.

I've sanded my rod to get it looser in a broken flange and back on the road until I could get the broken end out. I've also cut the end off a new flange and used it with the broken end still in there - had no issues- not recommending.

Pull the pump and check the length and fit of the pushrod. It should slide freely through the broken flange.

Remember to grease the new pump.
_________________
Repeat after me "I am smarter than metal!"

[Hula Hooped]

Your explanation sounds correct...Much appreciated. I'm currently looking for a nice used VW air cleaner assembly.. I'd like to have a stock one.. And your right, it's some (way too small) crappy chrome junkie one on there now... So, Pull the carb, and grab a rebuilt kit it will be.. As long as the measurements I gave you on the rod height are roughly correct..??? And Yes. (light bulb going off, After you said it twice, Sorry...) it's the Accelerator pump that saved my butt....Not the pump failing... I'm running a 34 Pict3 with a hole I drilled out for the autostick control valve... In terms of diagnosing... Look for something clogging a passageway upon teardown? Seems straightforward enough... I'll still post a pic of engine bay.. BC everyone on here I see likes Pics. Lol (And I'll wait patiently for someone to thank me for saving another one...As I've dreamed that day will come. Lol I do feel like a friend after so much reading over the years.. But this is only my first question on the forums..) I do have some "Mad Love" for some of the contributors on here.. And would probably follow them off a bridge if it was in the instructions... Step by step..

[cbeck]

Don’t take off carb top yet. Remove air cleaner, look down carb throat, work accelerator linkage, look for a fuel squirt. If it squirts you have fuel pumped up to the carb and time to concentrate on idle circuit. No fuel squirt, time to work your way back to the fuel tank, starting with the fuel pump.
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My cut in half and rebuild thread
www.thesamba.com/vw/forum/viewtopic.php?t=647779

[Jimbug57]

I'd fill that crab float bowl with fuel (through the vent in the carb throat) and see how it runs before I took the carb apart. But I'm weird and lazy.
_________________
Repeat after me "I am smarter than metal!"

[Hula Hooped]

Thanks JimBug57, I did read up on, and understand (now) the differences in push rod length and the various pumps VW has used.. I believe my combination to be correct... 1/4 inch above the flange, and the pump has the lever, "inset" into the body.
I think I'm doing what you did... That you don't recommend... As the flange broke off very "clean" in two pieces, one in my hand, the other in the block.. I believe it only broke when I tried to remove the flange. (I only assume it was in one piece before that.) So I just "restacked" the two pieces upon install, and I made pretty certain that the pushrod moved freely in the flange, like really no resistance at all going up and down.. I did put a bit of grease on the rod itself, (as my reading says they heat up and expand, etc.) so I was focused on the motion of the pushrod and anything that would hamper up and down motion... Seems like it should be no different (With the flange in two pieces) One side anchored firmly in the block, and the piece I did get out bolted down with two bolts under the pump.. I considered doing the "procedure" for the flange removal, but (although I put Much trust in these forums.) I couldn't in my head see the difference... IMHO if I used "superglue" (which I didn't) The flange would be one piece again. But I do appreciate your input, as I was trying to cheat out on doing the flange removal. (If I had the parts for that laying around, maybe.. Maybe not..LOL) As I really don't see a difference, currently at best, it has a crack in it.. What are your thoughts on running a drill bit down the inside bore of the flange and expanding the inside? I entertained that thought, but wasn't sure. Was afraid of making the hole any wider (than Specs?). Didn't want the pushrod to be too sloppy... Thanks again. Keep you posted on progress.

[Starbucket]

The accelerator pump is what got you home, it's ok, does the carb have a idle cutoff solonoid on the side? if so does it click when you turn on the key? Maybe the tank has rust clogging the outlet not letting gas get to the pump, Remove hose from fuel pump (from tank) and blow in it and listen for bubbles in tank. You can put the hose from pump to the carb. in a bottle (remove coil wire so no start) and crank the motor and see if you get a good stream of gas.

[Hula Hooped]

JimBug, I'm also slightly lazy myself, so upon further inspection, I was able to get it started up again tonight. Ran rough, then sorta smoothed out (on choke) enough for me to spray some carb cleaner down the carb. used the old "Starve it for air" with my hand, while accelerating method ( a couple of times) and tried to loosen, flush, run through any foreign matter that may have entered. Seems to have helped a bit.. But I'm on your train of thought here. I think something may have entered the venturi. So, as soon as I can. I'm going to rebuild and inspect the carb for anything unusual. May not be able to get back out to the garage for a couple of days to pull the carb. but as soon as I do, I will be back on here to report what I found. Now also questioning why she died at speed, (when warmed up) then I limped her home, and (without doing anything further) She fired up relatively easy tonight. Would be hard to tell if the Fuel Pump Flange did (for some reason) expand and kill the flow, (and feel like a blocked jet may feel).. I really don't think that's the problem.. But I also don't know how I could tell. Perhaps I should bite the bullet, get my tap out, do the "flange procedure" and replace that with a brand new flange to rule that possibility out of the equation. I'm feeling that is a long shot, but You never know. My thinking is: I don't believe that was my original problem. (Flange expanding) I'm pretty certain the fuel pump dying was my original problem. When I cranked her with the old pump, and the hose off the carb, not a drop pumped out. Bone dry.. And when I pumped the old pump by hand, it felt like it had no pressure to it,. Like the diaphram was leaking.