TheSamba.com :: View topic

Wed Oct 24, 2018 5:00 am

Hi All,
I am just completing my 1641 Type 1 beetle engine and running in to a problem when fitting the mechanical fuel pump.
When installing the pump on to the engine it does not sit flat on the plastic pedestal, with it just sitting a little high. I thought this would be fine as the push rod is slightly protrudes as it should.
when tightening the bolts either side of the pump the plastic pedestal cracks before the pump meets and sits flush. You can here the plastic breaking with a good 3mm gap between the pump and plastic pedastal.
I have measured the push rod which is correct and everything is new. Any ideas on what im doing wrong?

Wed Oct 24, 2018 5:13 am

What pump and rod are you using? There are two types of each, mixing them will be problematic

Wed Oct 24, 2018 8:10 am

Sounds like a 108mm pushrod was used with a fuel pump that needs the shorter 100mm pushrod. That will cause something to break. Typically a "slanted" fuel pump which fits with an alternator takes the 100mm pushrod.

Wed Oct 24, 2018 8:41 am

Hi guys thanks for the quick reply. I've measured the Rod and its a 100mm the pump is an alternator style. I've asked on other forums and had little to no luck. It was suggested that the engine might be warped and not sitting flat but I just don't see it

Wed Oct 24, 2018 9:09 am

That pushrod looks aftermarket and it should be coming to a dull point on one end like a pencil. http://vwparts.aircooled.net/Fuel-Pump-Push-Rod-100mm-Alternator-Fuel-Pumps-p/113-127-307a.htm

Not sure if the pushrod is sticking up too far causing your problem. I would get a new flange and pushrod and stack of gaskets then install the flange and pushrod and turn the engine and measure how much the pushrod comes out above the flange and if that is in spec.

I don't have the measurements offhand but they are in the orange Bentley manual.

Wed Oct 24, 2018 9:11 am

The specs for the pushrod lengths and throw are in this post
https://www.thesamba.com/vw/forum/viewtopic.php?t=694754&highlight=alternator+pushrod

Wed Oct 24, 2018 11:02 am

Thanks for the info thing. It's the only part that's not new. Failing that any other ideas

Wed Oct 24, 2018 1:22 pm

The flange should drop into the hole without having to be forced in. If it is tight then lightly sand the outside of the flange portion that goes into the case so it drops right in without any resistance.

Wed Oct 24, 2018 1:27 pm

The flange should drop into the hole without having to be forced in. If it is tight then lightly sand the outside of the flange portion that goes into the case so it drops right in without any resistance.

Wed Oct 24, 2018 2:59 pm

Hey Jimbob202 . . . WELCOME to TheSamba!!! :D

It's possible that the lever on the pump is not sitting on TOP of the pushrod during installation . . . that is, the EDGE of the pump lever is pushing on that bevel around the end of the pushrod and thus pushing the pushrod to the side when the pump is drawn down with the nuts.
Get a felt-tip marker (Sharpie) and color the tip of the pushrod and the pump lever . . . then, set the pump onto the studs to see where the marking is wiped away.
You might need to use a "shoehorn" to install the pump . . . like a thin strip of sheet metal . . . set the "shoehorn" on the end of the pushrod, set the pump on top of the strip, thread the nuts on and tighten almost all the way down, and remove the strip just before the last couple turns of the nuts . . . this will help guide the lever over the end of the pushrod rather than letting it catch the side of the pushrod . . . make sense? :wink:
Jimbob202 wrote:

Wed Oct 24, 2018 3:38 pm

That looks like a generator style pump to me.

Wed Oct 24, 2018 4:02 pm

Jimbob202 wrote:

I agree with 57Blitz. Look at the picture of the cracked plastic. You can see where the lever on the pump went straight down beside the pump rod and split the block like a chisel.

Mike T

Tue Oct 30, 2018 5:30 am

Hi all,

So to keep you updated the fuel pump is now installed and working without breaking anything 👍 :)

Turns out that the pushrod was badly worn. As the end had rounded and became less of a point there was no movement to adjust the pump to sit Liskeard on the push rod meaning it just missed and cracked the pedastal.

Thank you to everyone that helped. Especially to Thing74 who spotted the worn push rod

Just incase asinine else has this issue

Tue Oct 30, 2018 11:17 am

Jimbob202 wrote:
Just incase asinine else has this issue

DAMNED AUTO-CORRECT!!!!! :D

Tue Oct 30, 2018 2:28 pm

ok, I was gonna tell ya you wasent putting on the fp right... not pushing down on the rod but pushing the side of the rod...