TheSamba.com :: View topic - Fuel Pump Failure, Huge Leak, Safety Wire Fix

Tue Aug 22, 2023 9:18 am

67conv wrote: Just a graphic reminder of what can, and in my case DID happen last Friday! The bottom photo clearly shows the outlet pipe had popped out of the fuel pump housing, allowing fuel to spew out and ignite!

Holy Smokes! Your beautiful convertible! I never thought I'd see that either.

You are indeed fortunate [-o<

Tue Aug 22, 2023 9:22 am

67conv wrote: I was extremely fortunate that someone who was witnessing the fire ran over with a fire extinguisher, as I foolishly didn't have one on board! Be forewarned! I never thought it would happen to me in 50 years of acvw ownership!

Glad no one was hurt, and that your car wasn't damaged too severely (nice car!)

Tue Aug 22, 2023 9:53 am

John, that sure sucks. But on the bright side, perhaps this will help in your decision to go back to the original Ruby Red color. (I know you need an excuse to use your N.O.S. fender beading)

Tue Aug 22, 2023 5:23 pm

67conv wrote:

Just a graphic reminder of what can, and in my case DID happen last Friday! The bottom photo clearly shows the outlet pipe had popped out of the fuel pump housing, allowing fuel to spew out and ignite!

Arggg, that sucks!

In addition to it popping out, I noticed that aftermarket tube doesn't go into the pump very far.
The original Solex ones have a longer tube that sticks in.

Tue Aug 22, 2023 7:02 pm

Thank gawd the black plate survived!

Tue Aug 22, 2023 7:06 pm

To be honest - it doesn't take much to safety wire that stuff in. And I worked four decades for a sister company of Loctite, and they - and Permatex - make good quality products.

Tue Aug 22, 2023 9:08 pm

I will always advocate for a threaded and barbed connection if at all possible. A 1/16" NPT barbed fitting is a good fit for most carburetors and fuel pumps that have the press-in style tubing inlet/outlet.

My charts show using an 'A' letter drill for the 1/16" NPT cut tap if taper reamed, or a 'C' drill if not reamed.
:arrow: 'A' drill size is .2340, which is only .0004" smaller than a standard 15/64" drill. I would not hesitate to use the 15/64" drill here.
:arrow: The 'C' drill is .2420", with the closest fractional drill being 1/4" at .250", and I would not suggest using it. .080" is quite a lot of thread engagement to lose in soft aluminum.

I'm using 1/16" NPT to 4AN fitings on my parts, but I used a 1/16" NPT to 1/4" barb fitting on my bus carburetor with regular fuel hose and it worked very well.

https://www.amazon.com/MettleAir-Single-Tubing-Fitting-Connector/dp/B007QTZ3NM?th=1

https://www.amazon.com/Hose-Barb-Fitting-Brass-Units/dp/B07DJ5RB6X

Wed Aug 23, 2023 7:06 am

bluebus86 wrote:

one problem with a threaded fix is the that the tapered thread can exert tremendous force on the old, weaken, already stretched aluminum carb casting, and that could allow the casting to split.

I think Solex carburetor bodies are cast from a zinc alloy, not aluminum. I could be wrong.

Wed Aug 23, 2023 7:16 am

EverettB wrote:

Arggg, that sucks!

In addition to it popping out, I noticed that aftermarket tube doesn't go into the pump very far.
The original Solex ones have a longer tube that sticks in.

And ironically - I have a rebuilt orig. Pierburg pump (and correct 205K dist., 30 PICT1) for this '67 tucked away for the moment awaiting installation on the early '67 H0 20xxxx long block going back in soon. This was my "driver" engine, and that damn fuel pump was a recent "lifetime guarantee" Auto Zone replacement unit, because their gold top version failed at the drive rod!

iowegian - I've been already working on that Ruby Red re-do this summer, actually! Painted the orig. factory fenders single stage Acrylic Urethane L456. Will do body next, putting that nos beading to work soon! 8)

KTPhil - Thanks for your compliment! Yes, I had just dropped off my gf at a friend's house. Very lucky.

Busstom - I had the same thought on that black plate too! lol The stack of stickers got a little singed around the edges, but it survived pretty well, considering!

Lesson Learned!

Wed Aug 23, 2023 7:31 am

Cusser wrote: To be honest - it doesn't take much to safety wire that stuff in. And I worked four decades for a sister company of Loctite, and they - and Permatex - make good quality products.

Safety wire in this photo

Wed Aug 23, 2023 7:34 am

That's a connection I would trust!

scrivyscriv wrote: I will always advocate for a threaded and barbed connection if at all possible. A 1/16" NPT barbed fitting is a good fit for most carburetors and fuel pumps that have the press-in style tubing inlet/outlet.

My charts show using an 'A' letter drill for the 1/16" NPT cut tap if taper reamed, or a 'C' drill if not reamed.
:arrow: 'A' drill size is .2340, which is only .0004" smaller than a standard 15/64" drill. I would not hesitate to use the 15/64" drill here.
:arrow: The 'C' drill is .2420", with the closest fractional drill being 1/4" at .250", and I would not suggest using it. .080" is quite a lot of thread engagement to lose in soft aluminum.

I'm using 1/16" NPT to 4AN fitings on my parts, but I used a 1/16" NPT to 1/4" barb fitting on my bus carburetor with regular fuel hose and it worked very well.

https://www.amazon.com/MettleAir-Single-Tubing-Fitting-Connector/dp/B007QTZ3NM?th=1

https://www.amazon.com/Hose-Barb-Fitting-Brass-Units/dp/B07DJ5RB6X

Wed Aug 23, 2023 3:53 pm

Cusser wrote: .... And I worked four decades for a sister company of Loctite, and they - and Permatex - make good quality products.

As did I Cusser, but not as long as you.

I agree wholeheartedly. Loctite puts a huge amount of time into research and by searching their database you will find a product that will "glue" that connection into place permanently.

Thu Aug 24, 2023 5:32 am

viiking wrote: Cusser wrote: .... And I worked four decades for a sister company of Loctite, and they - and Permatex - make good quality products.

As did I Cusser, but not as long as you.

I agree wholeheartedly. Loctite puts a huge amount of time into research and by searching their database you will find a product that will "glue" that connection into place permanently.

At the end of the day, if owners want to safety wire a fuel fitting on their carb or fuel pump, they should do that. If they want to thread in fuel fittings, by all means do that too.
I consulted with Loctite when selecting their product I use to secure those inlet and outlet tubes in both fuel pumps, carbs and other parts.
I then did a bunch of tests after reinstalling the tube in castings to see what it would take to remove the tube from the casting. They simply won't come out unless you get an acetylene torch and heat the casting up to 500° to melt the Loctite. Fuel exposure is not a factor as the connection where the tube is pressed in see's no fuel.

My VW's are running rebuilt carbs and fuel pumps with their tubes pressed in and secured with Loctite. I have zero worries about those connections after my tests before using it. Other qualified rebuilders also use loctite products to secure fittings, tubes and other nuts/bolts.

I tell all my customers that they need to check their carb brass fuel inlet tube for tightness as well. If my friend [email protected] has rebuilt the carb, no need to worry about that inlet tube. He secures them too. Those tubes are often not tight in the casting of unrebuilt carbs. You must Loctite them in.

Thu Aug 24, 2023 10:10 am

Years ago I used to roll brass fuel fittings between two coarse files to dimple them, before re-inserting them. I used a little JB Weld, but the proper Loctite would be even better now.

My rebuilt carb (VolkzBitz) had a threaded and barbed fitting into the body; I may ask my fuel pump rebuilder (Sparxwerks?) to do the same when that time comes.

Sat Dec 09, 2023 6:28 pm

JB weld is good enough.