Injection Pump Seal Replacement

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Sharkey
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Injection Pump Seal Replacement

Post by Sharkey »

Long story made short for the forum.

In July 2005, I decided to take a short run in the EV using the Pusher. Seemed to be out of fuel, and putting more in didn't help, the injection pump wouldn't draw from the tank. I tried priming the pump with a Big Gulp cup filled with Biodiesel, and it took about 16 ounces and kept swallowing. A look on the ground revealed a big puddle of fuel, it was pouring out of the front shaft seal as fast as I was pouring it in.

After four years of continuous exposure to B100, my shaft seal was worse than leaking, it was non-existent. Blowing into the input hose of the pump blew droplets of fuel out the shaft.

A little research revealed that the seal is fairly easy to come by, but the task of pulling the old seal was daunting. Prying it out with a screwdriver seemed to be an invitation to a temper tantrum and possible shaft damage.

So.... a few hours of fabrication today, and I now have a nifty set of seal puller jaws for my gear puller:

Image

The jaws are made out of a couple of spare 4mm allen wrenches that were ground down to allow them to enter the space between the shaft and the seal body and then were welded into slots cut into some steel plate that was drilled to fit into the puller body.

Why allen wrenches? High carbon, tempered steel with a 90° bend at the end, perfect tool stock with only some grinding necessary to make it fit.

There is about 0.090" between the shaft and the seal body, so the ends are ground down to approximately that thickness. I put a thin strip of aluminum cut from a soda can around the pump shaft to prevent scratches or nicks while pulling the seal.

Here's a close-up of the hook end of one of the jaws:

Image

The viton seals are as follows:

Main shaft seal:
ID: 17mm
OD: 28mm
Width: 7mm
Lip type: ADL
Material: Viton

Control and cold start shaft O-ring seals:
ID: 6mm
OD: 10mm
Thickness: 2mm
Material: Viton

I also found replacements for the O-rings under the cold start and timing advance covers, but the part descriptions on my receipt don't give sizes.

Here's a piccy of the front shaft seals, complete with part numbers. The 'V' at the end of the part # indicates viton:

Image
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