FSS failure - A few Questions

PossumTruck

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Almost was stranded last night - walked into the store, 5 min later walked out and crank/no start. OOF.

Poured a bottle of water on the IP to see if I was finally at that stage - no dice. Started wiggling wires on the IP and still nothing. Guy is asking me if I need a jump - no buddy, I got plenty of cranking, but thanks. Called my wife, all that.

Before she get there, I wiggle stuff again and the truck starts. Hallelujah. I drive the 5 miles home. I'll deal with it tomorrow.

No start in the morning. Have 12v at the FSS terminal but no click. Potential culprit identified.

Today I thanked my stars for pulling a couple IPs off of junkyard trucks a couple years ago - I took the junk IP that looked the worst of my spares and tested the FSS to ensure it worked. All good. Popped the new-to-me FSS from the junk top cover into the less-junk top cover, reassembled, and it fired right up ( I did scotchbrite all of the metal contacts, nuts, etc.; I'm not a savage).

To say it was obvious that the old FSS was bad would be..an understatement.
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They clearly aren't supposed to look like that (although today is the first time I ever laid eyes on this part - new or nasty)

There was also this half-washer thing stuck to it (magnetically) when it came out. I would love it if somebody knew what this was, and potentially where the other half is. I didn't find it in the top-cover area. But I run a wmo mix so maybe it was hiding in the little bit of fuel I couldn't get out. Missing metal fragments are a cause for alarm in most mechanical things, to the best of my knowledge and recollection.

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And, Finally, an interesting thing. The rear bolt in the top cover had some strange tag on it - attached with wire in a hole drilled through the head. Curious as to whether anyone has seen something like this. New to me, maybe not to everyone else.

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A pressing question in my mind - what caused this? What should I be looking out for? I don't want it to happen again, although I could just carry a spare top cover and a couple extra tools (I normally don't have a 3/4 wrench and a flathead in my truck toolbox). Any comment appreciated.
 

busman1978

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The rear bolt and tag may be a tamper evident from a rebuilder. I've seen them on some VW TDI pumps. They use the safety wire and tag to prove the customer hasn't gone into the pump. I can't vouch for any of the other items, as injection pumps is where the magic happens. I generally work on everything up to the pump.
 

Ferdy Mint

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FYI check out my thread on this issue.

 

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