[T2] Power loss in 4th

[jules]

On Mon, Oct 12, 2015 at 1:24 PM, Avocado Tom Tarka <avocadotom at gmail.com>
wrote:

> Hi volks,
> - only happens when going uphill, particularly with steep grades
> - happens primarily in 4th but may just be RPM related: it seems to occur
> below ~2500 rpm (just noticed it in 3rd)
>

sounds like you're lugging the engine. 4th gear 2500 rpm UPhill in 4th in a
1600 sp? Sounds like a recipe for engine overheating to me. You've got to
keep the RPMs up to keep the fan moving - especially critical under load
(going uphill in 4th).

When is the last time you adjusted the valves? Are they getting tighter in
time or looser? Valve that are constantly getting tighter at each
adjustment are an indicator of overheating at the head.


> - hear ticking sound from carb after stopping to cool down (like a wind-up
> kitchen timer ticks)

- watched fuel getting sucked through pre-carb filter after stopping to
> cool down
>

sounds to me like the needle valve in the carb isn't closing fully - could
be the float has a leak and is taking on fuel, or the valve itself needs
cleaning/replacement.  An Easy way to check - after a long run - stop
engine - disconnect or clamp off fuel supply to the carb. wait 15 minutes,
open the carb and see if it's full or drained down. (always have fire
suppression means available when working with fuel system ESPECIALLY near a
hot engine)



> Bus also seems to be trending towards overheating when the power loss
> occurs. Not sure if that's related.
>
>
Well sure, if you're running uphill in 4th at 2500 RPM then you're creating
the overheating situation - that's probably directly related to your power
issues.  Try running those uphills in 3rd at around 4000 rpm instead.


Good luck~
jules
'75 '78 westies
troy ny