[T3] Knock Knock

[Daniel Nohejl]

Jim, 

Your message came through just fine. I wonder what’s up with the other ones?

> Use a long screwdriver as a stethoscope to try to localize the sound a bit 
> more.

I have a “mechanic’s stethoscope”, but haven’t been able to isolate anything beyond what I’ve reported so far. I can try again though. 

> You didn't mention that we had to tighten up the #3 & 4 head studs when you 
> were here earlier this summer. My concern would be that they have 
> loosened again. Check the compression on that side, and, if it's bad again, 
> retorque the bottom 4 studs again. If they are loose, see if they will tighten 
> up and if they do, check the uppers, too.

I checked when I had the rocker assembly off last weekend and found that 3 of the 4 lowers were slightly looser than spec which I found odd as we had tightened them about 1,400 or so miles ago at your house. I checked again yesterday and 1 of the 4 was ever so slightly loose. Tightening it back up had no effect on the noise though. Is it still worth doing the compression test?

> If the head had come loose, however, the valves should have loosened up, 
> too. But you said the valves were fine, so I'm puzzled, unless the valves had 
> loosened and you tightened them. (If you have to retorque the heads, you'll 
> also need to reset the valves.)

Prior to pulling the rocker assembly, the valves were in spec and I reset them once I put the assembly back on. I think I’ve been pretty thorough in regard to looking through all the external stuff. I even checked all the pushrods and all were straight. I found a looseness in the “shell” of the upper heat exchanger which seemed a likely cause of the noise, but that proved to be a red herring. The noise is definitely coming from within the case and like you said, the cause can’t be anything good…


--Daniel