Mark Maras

Be sure the carb nozzles are returning to the up position when the choke is off. The nozzle linkage (small flat bar with bent ends) that pulls and pushes the nozzles down and up gets warped over time and needs a bit of twist with pliers to align both ends to their attachment points.

I watched an episode of Engine Masters that focused on heat shields. I was amazed to find out that the single-layer (aluminum) shields were hotter on the side away from the headers. The side facing the headers was cooler. The only heat shields they found that were effective were made of sandwiched materials. Engine Masters also did an episode on cooling headers. Ceramic coating won the lower temperature contest.

I had a fan clutch that locked into a no-slip condition. It \was extremely noisy (it sounded like a small plane prop), and it felt like it cut the horsepower in half. However, it did cool well.

Hi Jalex. I had an overheating problem while sitting in traffic with my 240 before I had the radiator recored with a larger core. Before the rad fix, I found that shutting down the engine instead of letting it idle and build heat was a good temporary fix.

Same thing here.

I've found removing the window crank clip with a shop rag to be quite easy. Simply slide a rag between the door panel and the crank down to the spline and pull on one end of the rag, making a 360-degree turn around the spline. The rag catches one end of the clip, pops it out, and the rag usually captures the clip.

And the pistons should drop at the same rate.

When I removed and replaced the hood many years ago, one front corner stood proud. After multiple failed adjustments, I had a friend sit on the proud corner while I tightened the hinge bolts. It was too low when I tightened the bolts, but it was perfect when my friend got off the hood. I think it was a worn, sloppy hinge that caused it.

Dry ice is the safe way to prevent it from catching fire. (blowing up) A crew pulled a leaking underground gas tank where I worked. Before cutting it up with a torch, they threw in buckets of dry ice and waited until they could see CO2 fumes coming out of the top—no fire or explosion when they cut into it.

Before you buy a new sender, submerge your old one in CLR for 24-48 hours. You'll be amazed.

I agree with using Marvel Mystery Oil on the valve train and in the cylinders. MMO contains oil for lubrication and a solvent to free sticky valves and rings.

Submerge that sending unit in CLR for 24 - 48 hours. It will come out clean.

We didn't learn our lesson back then. We have a similar problem now with the National Guard attacking US citizens,

Shrinking sheet metal with heat and cold is a very effective method. There are a lot of auto body repair tutorials on YouTube that include sheet metal shrinking.

The reason I asked is that I had a similar problem many years ago. The difference is I was in a stock 71 Z on the freeway when the car slowed and wouldn't go above 3000 rpms under load. It would free rev to 6000 rpms with no hesitation. My Dad knew instantly what was wrong. I blew out the fuel filter under the hood, and it ran great again. It does seem odd that a poor fuel supply would occur when you're working on the electrical system, but I'd give the fuel system a quick pressure and volume test to rule it out. You also mentioned that there was a slight problem above 4000 rpms in the past. Maybe it was caused by a lack of fuel, and just got worse.