Macrobb
Full Access Member
to the OP...
while you have your sticks out, I would do a leak down test.
why go through the trouble of replacing the sticks if you have a bad valve or lifter?
I just want to throw a couple of things out there:
1. I'm less concerned about a bad valve than you are.
Why? In my experience, if a valve or lifter isn't working right, you *know* it - you'll get popping noises and other weird sounds.
Plus, a valve really going bad is pretty rare, except on newly rebuilt motors(mainly due to tolerances not being followed...). You may have a valve not seal perfectly, but it takes a *lot* to cause a misfire that way.
Also, even with /really/ bad rings, once the engine is running, it takes a massive amount of leakdown to actually not fire, considering the volume of air being compressed vs the size of the piston ring area.
2. Every single IDI I have come across has needed injectors. Just plain and simple. So, unless you *know* the injectors were replaced recently(and with *good* ones), that's a very, /very/ likely problem.
Pumps going bad is also really common, though in my experience what usually ends up happening is that something sticks in the retarded position internally. The pump still injects fuel, but about 6 degrees retarded compared to where it should be. Advancing the pump by that much ends up letting said worn out pumps work, at least temporally.
3. To add to that, I've bought multiple "non-running" or "barely running", "parked under a tree for a couple of years" rigs. They have *all* been retarded when I got them started, by probably around 6 degrees. Advance the timing enough, and you end up with a decent running rig(I end up replacing the injectors as soon as I get around to it, too, which makes a better running truck).
I also had one truck that I bought running decently, drove it home, parked it for about 8 months... started it up, and the pump stuck retarded just like the others.
4. If you are going to be doing a leakdown or pressure test(honestly, a pressure test is probably easier and will be good enough), you use the glow plug holes, not the injector holes.