Fuel Pump Tips

Anyone got any tips for preloading an upright fuel pump, at the moment Im thinking a punch in me vice and clamps or fashioning a jig out of bolts and a bit of wood. Any advice on a method apreciated.

 

You don’t need any for a stock type 1 pump. Turn the engine until the pushrod is at its lowest, then tighten the pump down.

 

TBH I just tighten it down evenly. It will push down by hand the spring is only a few kg force. I check pumps by poking the lever with a finger.

 

/\ this. No need to do anything else.

 

If you are trying to get a pin in it, a finger is probably still easiest.

 

I was under the impression that you had to preload the diaphragm to prevent it prematurely ripping prior to tightening it down?

 

Its probably true for some half baked British engine.

The VW diaphragm is at full load while it is sitting around. When you press on the lever you compress the spring and reduce the pressure on the diaphragm.
The power stroke is on the release to avoid the force of the push rod being directly converted into uncontrolled pressure. The spring is the force that pumps.