You were absolutely correct. Timing device cover is leaking. I located another, which is the belt cover??...and once you've found the leak, you can fix it by replacing whichever seal is leaking. A generic Bosch VE Injection Pump rebuild kit has all the seals.
(My money's on the timing device cover O-ring.)
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Oh and while you're working in the area, remove the top timing belt cover and make sure the IP front seal isn't leaking diesel onto the timing belt. The timing belt should be clean and dry.
Can this seal be replaced w/o pulling the pump? Just curious.The arrowed seam in your photo is another notorious leak spot. The rebuild kit has the seal for that.
Yes, the top cover seal (large rectangular thing in the rebuild kit) and throttle shaft seal/O-ring (in the top cover) can be replaced easily with the IP in place. The timing device cover O-rings are a little more difficult, but doable. The distribution block seal is a nightmare with the IP in place.Can this seal be replaced w/o pulling the pump? Just curious.
I thought the front/rear shaft seals were the main leak points... I guess they're just the ones that are most likely to cause poor running/stalling?
You can't really damage anything with the priming pump... but seals fail.Awesome thank you. Got it assembled and got it started. Thank you! I think I many have induced another problem by maybe pumping the IP too much? Getting a small leak on the bottom of the fuel filter. Did I break it?
Besides an import shop that saw a lot of weird old diesels, at one point I worked for a tractor/equipment dealer with a lot more diesels. Every. Single. Last. Leaking Bosch VE-style pump had a failed o-ring exactly at that spot, and often nowhere else. Furthermore, generic O-rings that seemed to measure correctly failed immediately; only the Bosch (or Zexel, Diesel Kiki, or what have you) part worked. For whatever reason, this part of the pump seems exceptionally finicky, regardless of whether it was equipped with the timing device or a block-off plate (IIRC the seal is the same). Luckily it's not hard to change.
Thinking further, it's possible that the finickiness was exacerbated by using the wrong seal materials. Back when I worked at these places was right around when B2-B10 was starting to become the normal No.2 diesel, and before I learned about biodiesel's proclivity for eating EVERYTHING and knew to check, I'm sure many if not most of those O-rings were rubber or some other unsuitable material. In a nutshell, if it's not steel, stainless steel, aluminum, nylon, teflon, or fluoroelastomer (aka Viton), it won't get along with biodiesel - in some cases, even at B5 concentration.
You might consider using a sealant, preferably with the O-ring. Sealants that stand up to petrodiesel are slightly uncommon but out there. Those that stand up to biodiesel are very uncommon, but last night I discovered they do exist, in the form of fluoroelastomer caulk. So far I've found two manufacturers (Pelseal and Thermodyn), but the only place to buy it was McMaster... for $36 for a little tube.