[T2] Power loss in 4th

[jules]

Tightening valves are certainly a sign of overheating. Usually it's the
exhaust - not the intake - but not a good sign either way.

Back when I had a 1600 powered bus, after rebuilding it once by the side of
the road in nowhere nebraska, I'd try to never let my rpms drop below 3000,
especially under load - and especially with the 009 - which doesn't give
the the extra 'kick' of the added few degrees of vacuum advance you'd get
(and really need) under load. The engine is cutting out at 2500? you know
how the old joke goes right... Don't let it drop to 2500.

sounds like you've got a multitude of issues. overheating almost certainly
is one. Some of it's cause may be mechanically derived. Does the engine die
at idle, too? Some may be remediable by changing driving habits.

from the type2 library:
http://type2.com/library/cooling/coolsami.htm

more general resources:
http://www.vw-resource.com/overheating.html#keep


Start dropping below 3000 under load with the 009 - downshift.

and

Making sure you've got all the cooling parts in place NEVER hurts. Look for
obstruction to the cooling airflow (blocking the cool air intake in the
front of the doghouse. Check for vacuum leaks. Check the float and needle
valve. Adjust your behavior as necessary.

good luck
jules
'75, '78 westies
troy ny




On Tue, Oct 13, 2015 at 3:16 PM, Avocado Tom Tarka <avocadotom at gmail.com>
wrote:

> Jules,
>
> I'm starting at 3300 rpm and losing power and therefore RPMs. The engine
> starts cutting out around ~2500, which is about where I'd be shifting
> anyway, as it corresponds to roughly 3900 in 3rd (coming from 4th), or 4100
> in 2nd.
>
> The valves were adjusted that morning. Both #3 valves were tight, perhaps
> unsurprisingly.  That's been the trend for the last 2 or 3 adjustments, and
> I've been checking them frequently.
>
> Woot!
>    Tom
>
> ----
>  "We are MoTown. We are professionals. We're here to get the job done."
>
> On Oct 13, 2015, at 12:47 PM, jules <jules.herr at gmail.com> wrote:
>
>
>
> 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
>
>