How to Rebuilt a Early type 3 Fuel Pump

[pedro sainz]

[260KMN]

Great article, however it raises a question for me, i removed the pump from my 63's original un rebuilt motor recently as part of the teardown.
in line with the numbering system, VW2 is an early style parallel port pump, but using the numbers quoted it makes my pump build sometime in 1985.

So its obviously been replaced, but i am surprised that Pierburg were still producing pumps for a car that had been out of production for over 12 years.
Maybe they were!

[pedro sainz]

[260KMN]

Sorry Pedro i dont understand your reply.
I guess it is a replacement, but the numbers are stamped not raised.

[pedro sainz]

[260KMN]

Yeah ok i can see that difference. The raised bit, which must be a new casting. So my car had a replacement pump that was made on 7th January 1985.

[pedro sainz]

[pedro sainz]

this is testing my work of a NOS diaphragm 4.2

Wolfsburg West have a NEW Diaphragm redesign Available for $21.95
I bought it and test it



https://www.wolfsburgwest.com/cart/DetailsList.cfm?ID=113127141WW

left New Wolfsburg W
mid type 3 Original
right Old Wolfsburg W

left New WW right old WW


So Bye Bye Bye $80 hard to find NOS type 3 diaphragm

and remember to fallow step by step to restore it your self

thanks Josh Lucas for keeping your eyes OPEN and share this find
_________________
68 T34 1600 Automatic
62 T34 Cabriolet Prototype
N.O.N.A member #3
The Truth is Out There

[ataraxia]

The part was brought to my attention by Soren - he owns an early Type 3 but isn't on Samba all that often. I passed the information along to Pedro because I knew if anyone could validate, it would be him...

This is great news because it means that not only are there new parts available that will work for the early fuel pump but NOS diaphragm prices should drop like a rock (although it doesn't necessarily mean they will...).

[wcfvw69]

[pedro sainz]

[OKType3Tim]

During the recent Type3 Invasion, I had fuel pump problems with a Pierburg Squaretop type fuel pump that I felt I had rebuilt per the advice and instructions given. The tank was full, it was late afternoon and 92-96 degrees out. After a 20 mile run, during which the engine gradually sputtered more and more; the car gave up completely. A full tank of fuel. Plenty of fuel to the pump inlet. But absolutely nothing would exit the pump outlet. The immediate problem was solved by switching to a new style fuel pump. Back home, I tore down the pump expecting to find some catastrophic failure. But....nothing obvious. So, I started digging deeper. The rebuild was done with a kit from the local provider. I ordered a WW kit. Comparing them this evening...it became interesting. Given that the pump had plenty of fuel, but wouldn't pump I wondered if the fault was in the fuel cut off valve. The cut off valve seals against this port in the upper chamber of the pump:

The port has an OD of 6mm.

Here are three upper diaphragms. Left to Right: Just obtained WW unit, local provider kit, still flexible diaphragm from the spare parts box.

I took measurements on the section of the diaphragm that seals against the port:

WW unit: ID is 6.99mm. Very different arrangement on the way the seal is crimped in.
Local kit: ID is 7.16mm
Old unit: ID is 8.20mm

Also the WW unit will not seal since the outer flange diameter is larger than the diameter of the upper chamber.

Also notice that the springs are all different heights, and made with different diameter wire. The WW unit is clearly the strongest spring, and the local kit has the weakest spring.

My question is: Does any of this matter? What does an original look like and measure out to? Is this the source of the pump getting into a condition where it would not let fuel to the outlet?
_________________
'69 Squareback restoration
'69 Fastback restoration
'66 Type34

[wcfvw69]

I have a NOS Pierburg kit in my stash. I'll try to remember to get some measurements from it.

Personally, I'd be more suspicious of the valves in the top portion. Did you change those? The reed valve or the bakelite one?

I recently rebuilt a square top pump. I removed both valves like I've done hundreds of times. The were flattened, seated, etc.. I installed a new WW kit with their previous upper diaphragm. I could NOT get this pump to prime or pump, nada. I took it apart, installed an NOS top diaphragm and spring and still nothing. I could NOT figure out why it wouldn't prime. The valves were perfect.

I have a pile of used cores. I took the top off one, put it on this pump body and it immediately primed.

I still have no idea what's wrong with that top portion. I'd read in a VW service manual that if a pump stopped working like this to replace the top portion of the pump.
_________________
Contact me at [email protected]
Follow me on instagram @sparxwerksllc

Decades of VW and VW parts restoration experience.
The Samba member since 2004.

**Now rebuilding throttle bodies for VW's and Porsche's**
**Restored German Bosch distributors for sale or I can restore yours**
**Restored German Pierburg fuel pumps for sale or I can restore yours**
**Restored Porsche fuel pumps or I can restore yours**
**Restored Porsche distributors or I can restore yours**

[pedro sainz]

Have plenty NOS 100% Correct Type 3
If anyone need some 😁
_________________
68 T34 1600 Automatic
62 T34 Cabriolet Prototype
N.O.N.A member #3
The Truth is Out There

[OKType3Tim]

[OKType3Tim]

Reported the issues to WW. They are going back to mfg to figure out what has gone astray. And refunded my $.
_________________
'69 Squareback restoration
'69 Fastback restoration
'66 Type34

[wcfvw69]

Some of the rebuild kits from the past few years had the rubber vs. bakelite outlet valve/washer. I experimented with one once and installed it. I couldn't get the the valve to seal and removed it and threw it out. There was clearly a reason Pierburg used the hard bakelite ones.

Good to hear WW said they'd address that with their vendor. Did the retainer of the bakelite piece fit in the pump housing? In the past, it was too small.

The reed valve setting is important. It can't have any gaps in it or it won't sell when the pump is pushing the fuel out.
_________________
Contact me at [email protected]
Follow me on instagram @sparxwerksllc

Decades of VW and VW parts restoration experience.
The Samba member since 2004.

**Now rebuilding throttle bodies for VW's and Porsche's**
**Restored German Bosch distributors for sale or I can restore yours**
**Restored German Pierburg fuel pumps for sale or I can restore yours**
**Restored Porsche fuel pumps or I can restore yours**
**Restored Porsche distributors or I can restore yours**

[Adriel Rowley]

Read through this twice, great help which appreciate, though have a question: where does the rocker fit regarding the washers? Sorry if missed the answer and thank you for the answer.

My thinking is this is why the rod keeps slipping off the rocker.
_________________
Please consider I am Autistic, so I process information differently and still working on social skills. Thanks.

Dad's 1964 Beetle purchased September 1968.
https://www.thesamba.com/vw/forum/viewtopic.php?p=9252810#9252810

1971 Sunroof Squareback with Fuel Injection
http://www.thesamba.com/vw/forum/viewtopic.php?t=219811&highlight=squareback+rejuvenation

[Adriel Rowley]

My understanding was the fuel pump rod should have a maximum travel of 14mm, is this correct?

I was not getting 14mm in order to preload the fuel pump diaphragm, instead 13,30mm. Checked the pushrod length: 107,84mm.

Can I machine off 0,20mm off the spacer to correct for wear?

Thanks in advance.
_________________
Please consider I am Autistic, so I process information differently and still working on social skills. Thanks.

Dad's 1964 Beetle purchased September 1968.
https://www.thesamba.com/vw/forum/viewtopic.php?p=9252810#9252810

1971 Sunroof Squareback with Fuel Injection
http://www.thesamba.com/vw/forum/viewtopic.php?t=219811&highlight=squareback+rejuvenation

[wcfvw69]