Scrivyscriv's 1967 java green sunroof sedan (stock)

[aquifer]

[scrivyscriv]

First of all, thank you all for the feedback and thoughts and ideas!

I'll share some of my troubleshooting process to hopefully help someone else down the road with similar fuel-related problems: there are lots of topics on this all over this site!

Symptom is, when I'm idling at a prolonged stoplight, or when re-starting within a few minutes after a drive, the engine starts, then dies; each successive start attempt will get it to pop or sputter, but die immediately without responding to the gas pedal. After a few cranks, it no longer sputters, but just cranks and cranks.

I did a bit of work on it last night. Starting at the back, I removed the top off my stock Solex 30-pict 1 and checked for debris in the float bowl or jet. It was all clean, albeit a distinct yellow tint, from some old fuel I had in the tank prior to first fill-up. The Bentley book doesn't have any specs on fuel level height, or inlet needle adjustment. Reading through the chapter again I realize now I had two washers under the needle, which is incorrect for a -pict 1. It should be a single "gasket." So with that, I re-annealed the thin gasket, and reinstalled the needle sans extra washer. A float adjustment alone will not solve my symptoms, so at this point I know there is more to look for. While in there, I bubble check the float, and am glad to see it's in great shape!

Next I check the fuel tank for obstructions at the sock.

It's hard to get a good shot down to the sock; mine looks good with no significant junk around it. I was able to get a small amount of rust fuzz on a magnet; everything looks pretty clean in there.

After that I started to run some wire down the tunnel tube. The best thing I have for that is .032" stainless safety wire; it made it about three feet down the tube starting from the back. It's too flexible to do any good, being annealed. The next best thing is to blow 140 PSI compressed air back-to-front, which blew clear with no garbage or any visible debris coming out.

I did happen to notice a seep coming from my under tank fuel filter. It's just a cheap plastic but I didn't clamp one of the ends, and it opened up a bit so that was the source of my slight fuel odor walking past the Beetle in the garage. One replacement metal filter, a clamp, and two adel clamps to secure it from vibration and my fuel inspection is pretty much done. With a low-ranging fuel pressure gauge deaed-headed onto the pump, I measure right at 3PSI while cranking.

Oh yeah, I also had a helpful inspector with me

That brings us to today.
My sister is an awesome hair stylist, and since I had just finished working on this issue, I figured I'd take the beetle for my haircut I'd scheduled today. The 4-year-old wants to come with me, and we headed out with plenty of "cushion" time built in to the schedule. Which is a good thing, because almost exactly 11 miles later, waiting at an intersection to make a left, the engine idle dips down and stumbles a couple times, then dies. Same symptoms. I couldn't get it to restart, and a couple annoyed drivers later, the turn arrow cycles back on for me, and I push the car, with my 4-year-old, clear of the intersection into a corner gas station. I'm SO glad it was a downhill slope! I chuckled to myself imagining what it looked like, a random middle aged guy pushing a broke down beetle through a busy intersection the week before Christmas

The great thing is, this is all a very tactical way to continue troubleshooting! My first quest is to find out if I'm indeed getting fuel TO the pump. It burped a couple times as before, then came pouring out. There is a fuel vapor-lock component to this problem; but I keep on looking for more. Removing the fuel line going to the carb, and with ignition disconnected, there are spurts of fuel coming from the pump; I'm not really excited with the amount. It definitely looks "sus" as my kids would say. Unfortunately for me, I can't remove the fuel pump in situ, as the EGR provision on my intake combined with the large alternator body simply won't allow the pump to come up over the studs. I tried! Then put it back together and let the car sit for another few minutes.. It finally starts, after a quick prayer

We make it to the hair cut, then stop by auto zone on the way home, for an oil filter, got to change the oil in my daily driver 2008 F150. Old girl won't start at Auto Zone.
Then I had my breakthrough moment.

A mechanic from a shop across the street, who has worked on some vehicles that belong to a member of the local VW club, chats me up, and throws a couple of tips and ideas around; it finally starts back up and I turned the idle speed up quite a bit. She idles great, I drive home, and leave her idling in the driveway a solid 20 minutes with no failures!

Now, here's the kicker: I check the idle speed and find out I'm sitting around 1300 RPM - way too high. My idle RPM is masking a fuel pump delivery problem that only shows at low RPMs. It looks like this pump is defective and not delivering enough volume at idle; even though it's making pressure (which should be 2.9PSI according to Blue Bentley), it's somehow not able to push enough gas out at rated pressure.

This pump has been around. It failed on my 1971 bus with a burst diaphragm in 2014(ish), got back burnered, and I put a new style W.W. diaphragm on it somewhat recently - within the last three or four years - to use on this engine.

It's a pain to get to the pump, like I mentioned above, due to the intake and alternator, and that it's a generator-style pump. But it's highly likely the culprit. I guess a good check would be to make sure the push rod isn't an alternator-type while I'm in there changing the pump; during assembly I measured the extended height at 13mm, which is spec.

And there we are. To fix this, I'll drop another pump in, and install an adel clamp on the rear under-car fuel line to get it away from the heat exchanger; drop the idle back down to spec, and just see what happens.


Also it was pretty cool for my high beams to just TURN OFF on a dark two-lane road on the way home. Got a jankety low/high relay!
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Robert in Memphis
Dünkelgrügen 1967 Java Green bug thread
Engine rebuild thread
If you're ever in the Memphis area, you are welcome to stop by for advice and help.

[richparker]

I’ve always been told, as a rule of thumb to never put the fuel filter under the tank before the pump as vapor lock will occur. Not saying that’s your issue, but maybe.

Also looks like a brown piece of paper/carboard/old gasket at the base of the sock. Could just be the picture, but there is some discoloration there that looks like an object.

I use a similar metal filter, mines in the engine bay after the pump.
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’71 Westy build
Adventure thread
’65 Deluxe Build

[scrivyscriv]

Interesting, thanks for the tip, I’ve never heard that before. There were definitely air pockets in the line at the fuel pump both times. When I started working on the hard line plumbing on the engine, I’d originally wanted a metal mesh filter with AN fittings. But places like jegs are REALLY proud of them, if you can even find one in 1/4”.

The brown is a patch of dark rust - photos make it look like a giant turd in the tank


*edited for punctuation*
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Robert in Memphis
Dünkelgrügen 1967 Java Green bug thread
Engine rebuild thread
If you're ever in the Memphis area, you are welcome to stop by for advice and help.

[aquifer]

Maybe you should take out the filter completely and see what happens. You said you would use an adel clamp to hold it away from the heat exchanger, but maybe the vapor lock is an air bubble in the filter not caused by being too close to a heat source. Maybe the filter orientation is somehow restricting the gravity flow of the fuel....getting an air bubble stuck in there because of the orientation. Maybe the filter needs to be oriented vertically....

Just thinking out loud here.

I think I would try removing the filter temporarily and see how it acts. I doubt there would be much risk of debris causing issues in the short term. If it still acts up, then dig into the pump.
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Parts needed:
Front & rear NOS or used OEM door panels for a '67 in the original Gazelle color (dark tan/light brown).

[scrivyscriv]

The unintended consequences of re-engineering VW’s fuel line transition at the front engine tin: I’ve introduced a heat soak source to the fuel line. Because the aluminum bulkhead fitting is directly bolted to the engine tin, it’s conducting heat up into the fitting, and I think that might account for the small air pockets I had.

Repurposing some insulating washers from old seat belt plug bolts:

I’ve got the rubber and plastic washers sandwiched on the front tin now as a heat insulator.

And I rustled up some more adel clamps I had stashed, using a stainless clamp on the insulated fuel line, and a plastic clamp on the z-bar torsion rod. The plastic clamp slides just enough on the z-bar, and I’ve got pretty good clearance to the heat exchanger head. I’m not convinced this was a major issue; it’s winter, I’ve got the heater on during all my drives, at least cracked open 1/4 at minimum. There is most likely not that much hot air being exhausted at the exchangers.

So, this is kind of my price to pay the piper, for reworking this part of the fuel system.
I really want a reliable driver. At this point I’m leaning towards just swapping the fuel pump and pushrod out for an angled alternator style pump and redoing the fuel line there.

_________________
Robert in Memphis
Dünkelgrügen 1967 Java Green bug thread
Engine rebuild thread
If you're ever in the Memphis area, you are welcome to stop by for advice and help.

[scrivyscriv]

Over the years I've added a handful of fuel pumps to my stache. I found a pretty neat Spanish-brand alternator style pump that machined ok for 1/8-27 NPT threads, and I'm really wavering on installing 4AN fittings vs. slip on fuel fittings like stock. The security of AN fittings is appealing - they have tight, threaded connections and aren't prone to the same kind of failure that a slip on rubber fuel hose is.

But there are none of these modified fuel pumps at any local parts store, anywhere in the US. It's strictly custom. And fuel pumps are a failure item. So in a slightly ironic twist, trying to make this Beetle more reliable for a daily driver could actually make it less reliable as a daily driver, by making it harder to repair.

With a bit of down time tonight, I cleaned up a generator fuel pump. Using a suction sand blaster for its relatively low pressure compared to a pressure blaster, I carefully glass beaded all the aluminum parts to prep for an Alodine rinse. Using Alodine 1201 in a small bath, I was able to get complete coverage inside and out. The primary concern was protecting from long-term ethanol corrosion inside the pump.
Depending upon what kind of Alodine used, the surface prep, acid pre-wash, etc, there are various hues left on the base metal. This treatment leaves a slightly yellowish brown tint and chemically bonds to the base layer of aluminum alloy, forming a highly corrosion resistant surface film.

I've been trying to understand the failure mode of my rebuilt Pierburg fuel pump: low volume at low RPMs. The best I can come up with is a sticking inlet or outlet valve, causing fuel to simply cavitate inside the fuel chamber at low RPMs. If that's the case, then I could do like the Bentley manual suggests, and just replace the top half of the pump.
_________________
Robert in Memphis
Dünkelgrügen 1967 Java Green bug thread
Engine rebuild thread
If you're ever in the Memphis area, you are welcome to stop by for advice and help.

[scrivyscriv]

After replacing the top half of my Pierburg fuel pump in situ, I made an interesting observation.

First though, I tapped the inlet/outlet on the above-pictured pump, a Brazilian square top, and checked to make sure both the inlet and outlet valves were sealing okay. With the pump pushrod at the top of its stroke, I measured again, and verified the correct 13mm protrusion which matches this generator style pump. Then I bolted the lower half of the pump down which preloaded the diaphragm, and secured the upper half with it under tension.

The other issue I realized is that my flex fuel hose by the transmission was way too long and had a high spot where air could cause a fuel blockage. It was higher than the top of the fuel pump - not good.
So o shortened the hose and routed it more directly to the engine fitting.

Next I blew some air through the fuel line where it goes into the pump. Air went in, I heard it bubbling in the tank, and then…. Nothing came out. No fuel.

Rich, I think you’re right about the fuel filter under the tank. It’s not causing a heat related vapor lock; but it’s allowing an air pocket to form and obstruct liquid fuel flow. So the last step is to remove the filter.

The inlet valve on my old pump. There was significant white powder corrosion in the upper check valve area on the other side; and the inlet flap was resting slightly above the sealing surface. That may or may not have contributed to my problem; but it should seat flat, so this was definitely allowing the pump to make less volume per stroke.
_________________
Robert in Memphis
Dünkelgrügen 1967 Java Green bug thread
Engine rebuild thread
If you're ever in the Memphis area, you are welcome to stop by for advice and help.

[aquifer]

I’ve been following your fuel issue pretty closely because I’ll soon be reinstalling my engine and I plan to put a filter inline near the transmission. I realize that in an earlier reply, I misunderstood where your filter is located, thinking it was in the back near the transmission.

That being said, my related googling has brought up a question: are you sure that your filter is designed for gravity flow? I didn’t know you weren’t supposed to put the filter under the tank as richparker mentioned above, and that may be true, but it doesn’t make much sense to me. Gravity is gravity. I had a friend in high school who had a 74 bug. The filter was one of those common see-through plastic ones and it was under the tank. He ran it that way for years.

In any case, the bigger question is whether your filter was designed for gravity flow, or if it might be too “fine”, and is contributing to your fuel problem. Looking closer at your picture above, it appears to be one of those steel inline fuel filters that I THINK were designed to work with a fuel pump. I had a Chevy pickup years ago that had one of those between the tank and the engine. There was a pump inside the fuel tank that pushed the fuel through the filter.

That may not be the issue at all, but I’m curious what you find out!
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Parts needed:
Front & rear NOS or used OEM door panels for a '67 in the original Gazelle color (dark tan/light brown).

[scrivyscriv]

That could certainly be part of my fuel problem, this metal filter came in a parts stash I acquired this year and I don't have any info about it to look up. The first time I got stuck on Thanksgiving eve, I had one of those generic plastic clear filters under the tank, and it was leaking a bit so I replaced it with the metal filter.

I've got some Gates barricade 1/4" fuel hose coming in the mail that I'll re-do the under tank plumbing with. Replacing the fuel pump top half, shortening the fuel hose at the transmission to eliminate a high spot, and removing the added under tank filter should eliminate the problems I'm having.
_________________
Robert in Memphis
Dünkelgrügen 1967 Java Green bug thread
Engine rebuild thread
If you're ever in the Memphis area, you are welcome to stop by for advice and help.

[richparker]

The metal fuel filter is good, I’ve been use of them for years. It’s the location that’s bad. IMO it should be after the pump, no issues with it after the pump.
_________________
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’71 Westy build
Adventure thread
’65 Deluxe Build

[scrivyscriv]

“Hesitation of the engine or spitting back through the carburetor on sudden acceleration is usually a sign that the pump is not working properly.”

I finally found out why the choke cam weight would flip around 180° and cause the engine to run full speed. Yesterday after replacing the fuel line under the tank, I was working under the decklid checking idle speed, and when I held the throttle back, the engine bogged down and backfired in the carb. The backfire hit the choke plate and slapped the cam weight around, leaving the throttle lever to ride on the round part of the cam, instead of the stepped area, running wide open throttle.

This book was in a collection I bought on craigslist a few years ago, but the only reason I even pulled it out was because I left my blue Bentley in the back seat and was too lazy to go outside and get it
The Bentley doesn’t have any troubleshooting info for this condition. I was excited to find this exact phrase in the book because it described my problem now to a T!

So the engine does now have fuel all the way up to the pump, freely draining out when the line is cracked open. Next I have to fix the accelerator pump circuit on the carb or perhaps just swap in a replacement H30/31.

The sun visors from Wolfsburg West are nice, I’m glad I finally got them. It’s hard to buy “niceties” after buying “must have to operate” parts. I actually have to talk myself into buying interior parts and trim pieces!!

And, there are two guys in the classifieds selling two tools I needed! Fritz and Atom Werks, making a two-leg swingaxle bearing puller and a purpose made camber nut wrench for the front end, respectively. The tools are just as advertised - I really enjoy supporting other guys on the hobby who take the time to make a product that benefits all of us.

Once I figure out the carburetor situation I’ll post the fix here. This old Solex 30 pict 1 is different from the H30/31s I’ve worked on and used in the past.
_________________
Robert in Memphis
Dünkelgrügen 1967 Java Green bug thread
Engine rebuild thread
If you're ever in the Memphis area, you are welcome to stop by for advice and help.

[scrivyscriv]

No photos of any smoking gun, but I think I found the last little problem with the carb and fixed it

The accelerator tube was barely dribbling fuel when it should have been making a near-continuous stream! So the troubleshooting book from 1974 was right, the engine was leaning out on acceleration. I didn’t find any debris in the circuit. It shoots a healthy stream now and I even managed to find another electromagnetic pilot jet to replace the inop jet that was installed. It’s 57.5 and Bentley spec calls for a 55. I’ll have to really pay attention to see if it’s running too rich now.

Man, I’m so close! I was only able to hit 60MPH last drive. This accel pump may have been the reason. If I can hit a reliable 70 with no idling problems, I’ll be ready to start driving this refined green turd to work on the weekend!
I’d really like to have the sunroof sealed up before I take it to work in case of bad weather. The last two pieces - felt seal and rubber seal - showed up in my Wolfsburg West order this week.
_________________
Robert in Memphis
Dünkelgrügen 1967 Java Green bug thread
Engine rebuild thread
If you're ever in the Memphis area, you are welcome to stop by for advice and help.

[mukluk]

The accelerator pump shoots a quantity of fuel into the carb throat to overcome the natural tendency for the mixture to lean out due to the sudden drop in manifold vacuum when you open the throttle plate. It typically will not flow fuel once you stop moving the throttle arm, as such, it won't cause a lack of power at higher revs and thus limit your top end speed.

Lack of higher rpm power or top speed lower than it should be will usually be caused by a fault with the power fuel system, insufficient fuel through the main jet, air correction jet too big, float bowl fuel level too low, weak ignition system, or insufficient ignition timing advance.

https://www.thesamba.com/vw/archives/manuals/looklisten_11.php
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1960 Ragtop w/Semaphores "Inga"

[scrivyscriv]

Thanks for posting that! I’m looking forward to the next drive - after yesterday’s snow and ice clear up. Memphis gets snow every now and then, which all promptly melts and refreezes into some nasty back roads.
_________________
Robert in Memphis
Dünkelgrügen 1967 Java Green bug thread
Engine rebuild thread
If you're ever in the Memphis area, you are welcome to stop by for advice and help.

[scrivyscriv]

Wasn’t much to gluing the sunroof seals; it’s safe to say I heavily over-researched how to do it!

It all went together reasonably well with the 3M black weatherstrip adhesive I had left over from gluing up the floor pan seals. I’ve got it rolled up tight as we speak to help hold it all in place - the adhesive sets up fast, with plenty of wiggle room to get everything lined up.

I could do a better job rigging the sunroof panel, it’s low in a couple spots. But I’m ok with it for now.

From reading through other articles, I was under the impression the rear rubber seal sort of clipped in or something but that is not the case. It is just glued directly on.

And now, I’ve got a fully functioning and sealed sunroof! The cable rig took a few tries. I had to fabricate a new Teflon slider block for the front right guide. Then with everything lined up and the gear drive in the rigged location, I gave it a few cranks and everything looks great!

Our ice and snow is mostly dried up - I’m hoping to make a few trips this week to make sure I’ve got the fuel problem whipped.
_________________
Robert in Memphis
Dünkelgrügen 1967 Java Green bug thread
Engine rebuild thread
If you're ever in the Memphis area, you are welcome to stop by for advice and help.

[scrivyscriv]

I’m done with this carburetor.
_________________
Robert in Memphis
Dünkelgrügen 1967 Java Green bug thread
Engine rebuild thread
If you're ever in the Memphis area, you are welcome to stop by for advice and help.

[richparker]

Bum deal. Hope you made it home safe.
_________________
__________
’71 Westy build
Adventure thread
’65 Deluxe Build

[sportin-wood]

That suck, man....but I have to say that's a pretty cool looking picture. It tells it's own story...
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1966 Bug project
1973 Thing project
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"Relax, all right? My old man is a television repairman. He's got this ultimate set of tools. I can fix it." --- Jeff Spicoli

[scrivyscriv]

Yeah, I made it home. Engine started to Peter out a mile after I left the house, just as I was making a left turn into oncoming traffic. Got it started back up, then petered out again at a cell tower access road 1/4 mile from home.

The pump was making plenty of fuel.

The bowl was full - over even possibly overfull.

I don’t have time to keep futzing with this 30 pict, it’s been unreliable so far and I’m not interested in figuring out the nuances of this particular carb.

I’ll put together an H30/31 from my spares stash.

This was on the side of the road after the engine shut down.
_________________
Robert in Memphis
Dünkelgrügen 1967 Java Green bug thread
Engine rebuild thread
If you're ever in the Memphis area, you are welcome to stop by for advice and help.