151 a1

[fland 244]

Got it running
Compression at 119 to 120 all valves show right clearance
Back of manifold red hot after 2-3 minutes of run time..exhaust clear ...why is this

 

[frank8003]

Got it running
Compression at 119 to 120 all valves show right clearance
Back of manifold red hot after 2-3 minutes of run time..exhaust clear ...why is this

what fuel
what rebuild
valves tight, indicators wrong
exhaust plugged
on and on and on

 

[dmetalmiki]

Check the timing.

 

[m38inmaine]

From the TM
16. Engine has spark knock on hard
pull, overheating, hard starting, lack
of power.

Test 6. Perform ignition timing test. Clean crankshaft timing notch andpointer (fig. 2-201. Connect techometer and adapter as shown in figure 2-
28:test 4. Connect adapter and timing light as shown in fig. 2-29, tests 6
and 1. Start engine and set idle speed at or below 500 rpm. Timing notch
alined with pointer indicates ignition timing is in correct adjustment.
Timing notch above pointer or below pointer indicates incorrect adjustment.

I believe David is correct, I recall reading about glowing manifolds on the G503 site and timing was the cause.

 

[hambone]

Do you have or can borrow a timing light? You can run it off a separate 12V source.