Yeah, that's kinda where I'm at with this. My A&P is one of my best friends (lucky me!), and we work together, so it's not a "time" issue in that sense. Just gotta get her Code 1 for Oshkosh, so that's the time issue.
I've been reading as much as I can about the problem, so we don't waste a lot of time hunting around for the problem. Harry Fenton did a decent writeup about it, but it's not exactly what I was seeing. Based on the fact that it's reading way high and even when the throttle is retarded to idle, it stays up there, I do agree that it's "probably" not in the cable itself. (Unless it's something really odd, like the inner cable in the sleeve is twisted up or something) Seems to me, systems-wise, that it's probably an internal gearing issue in the gauge itself. Already called Mike at Skyport, and he says he's got a new Tach on the shelf, so it'll ship quickly and I should still be able to fix this before KOSH (If it is in the gauge). Anyway, won't know for sure on any of this until we start tinkering this weekend. We'll probably start with testing the system again with a drill, then swapping cables, then we'll yank the gauge if it still has those indications. I haven't run that plan by my A&P, but it seems logical to me. And one last thing, if anyone ever runs across an ExCello B-46 pump or a 530977 cam, gimmie a holler. My buddy has one on his shelf, but is saving it for a future project. Since he's extremely smart on the excello systems, I'm eventually looking to toss one of those puppies in. Thanks again! Matt Harting N2699H --- In [email protected], "Ed Burkhead" <e...@...> wrote: > > > I'm having a hard time imagining that a cable problem could cause the tach > to read extremely HIGH. Low or no reading at all I could understand. > > (I had a few seconds pucker factor when my tach dropped to zero when the > cable failed very low over the trees during takeoff from Antique Airfield in > Iowa. Then I saw that the engine was happy and I returned to home base for > repair.) > > For it to read high, I'd bet that the problem is inside the tach itself. > > If your mechanic has a spare tach cable, it might be worth spending some > time installing the replacement cable to see if that solves the problems. > Those cables do fail and I know I had to replace one when my Coupe was new > (to me). But I wouldn't spend a hundred dollars of shop time testing this, > personally. > > Ed >
