Exhaust gas temperatures - 3kwListeroid

[veggie]

Today I made the necessary adjustment to speed up my Listeroid and increase the kW out of the system for service as an emergency generator instead of a 450 rpm battery charger.

The changes involved...
1] Installing the correct generator pulley for 750 rpm operation.
2] Changing the governor spring to the stock 750 rpm version.
3] Slightly advancing the timing (it was retarded for slow speed operation and knock reduction).

For slow speed operation (450 rpm) I retarded the timing by screwing-in the IP lifter tappet by 1.5 turns.
Today, I backed out the tappet by 3/4 of a turn.
Not back to the factory setting, but just enough to advance the timing and still give significant knock reduction.

My question:
Does a few degrees of timing substantially effect the exhaust gas temperature (EGT) ?
The reason I ask is that after running the engine for an hour at full load (3kw) I noticed the hi temp silicone tape was burned off the first exhaust joint.
This tape has been on for many hours and has never showed any signs of heat stress.
I am trying to figure out which one caused the higher EGT's...

A] The timing retarded by 3/4 of a turn from factory stock ?
B] Or just the fact that I am now pulling full load 3kw (6hp) from the engine instead of 2kw (4hp) ?

Any ideas ?

http://www.youtube.com/watch?v=Af41jQcBP7M

Oh...and.... what's the normal full load EGT temperature on a Listeroid     anyone bothered to measure that ?

Cheers,
Veggie

[dieselgman]

I have only measured external manifold temps - 450 F. I would expect that exhaust temperature rise to mainly be due to the full load, much more than the timing changes.

dieselgman

[ronmar]

I would be curious what temp you actually measured before I get alarmed by it.  I have measured 610F with an IR at the first pipe fitting leaving the exhaust flange...  That was at just over 3KW during a sustained run...

[38ac]

The most quoted max temp figure is 1250 F. pre turbo (if equipped)    It would not surprise me that full rack operation would put a 'roid in the red zone of exhaust temps if for no other reason than the Indians disposed with the rack limiters that were standard equipment on the Lister. The only time you had full rack or what they called "excess fuel" position was as an aide to starting from cold.

[vdubnut62]

My feelings are that you will have a hard time getting the exhaust temps into the dangerously high zone on a naturally aspirated engine. I've never been able to do any damage and
I've seen my old JD 70 diesel pull tractor grunt hard enough to have flame coming out the stack. Yes it does have alloy pistons. YMMV
Ron.