The 351windsor in my 56 has mild cam and I have it running, indicating normal water temps but the third header tube back on passenger side is very hot. It glows red at idle after a few minutes. Ther is no exhaust from the headers back yet. The header is ceramic coated. Is this too hot and what can I do about it if it is too hot. Any ideas would help, thanks

 

Red tubes are generally caused by unburnt fuel. could just be a bad spark plug or timing is off. Then there are valve issues after that. That could be broken valve spring, bent push rods.

 

Check a couple of things:

First, check the timing. If it is really late, the exhaust temp will be high.

Second, check to see if your distributor has a vacuum advance. If it does, make sure that the vacuum line is hooked up (and hooked to the correct vacuum port), and see if it works. With the engine not running and the distributor cap off, use a vacuum pump to apply suction to the hose going the the vacuum advance mechanism. You should see the breaker plate (flat metal plate where the points are mounted) move around. If you don't have a vacuum pump, you could suck on the line, but you run the risk of ingesting some oil....so I recommend one of the cheap vacuum pumps that they sell at the auto store for bleeding brakes.

You should also use a timing light and, with the engine running at idle, see what the initial timing is...as you advance the throttle, the timing should advance. You'll need to find a manual with specs for the initial setting, and the total advance. Some distributors have both a vacuum advance and some mechanical fly-weights & both contribute to the total advance. The running check is to see if both systems are working and giving you the timing advance that you need at higher rpm settings.

If the ignition is firing too late, the fuel is still burning when it goes out of the exhaust valve...it could be up to 1800 degrees and it will make the steel exhaust tubes glow red hot. This is a bad thing.

Dan

 

If it's just the one cylinder, I think Carolina's tips are the likeliest. At idle I wouldn't expect there to be enough gas to turn it red no matter what. Make sure the coater didn't obstruct that tube somehow.

 

follow up question, will it be harmful to drive this truck to a garage where this can be worked on. It would be about 4 miles (10 minutes)?

 

Does it turn red even faster undere load? If so, I'd say yes, it will hurt it.

Are you sure you have the firing order correct? Did 351's change firing order like the 5.0's did?