Overheating and vapor locking

Hi Issac,

Nice car.

Where do you have your timing set? I have battled a number of older cars and overheating and come to find out, it was the idle was the issue. Basically, it is running too rich and gets hot quick.

The last one was my father in-laws 1956 Lincoln Mark II and it did exactly what yours does. I bumped the timing up and overheating stopped.

Main reason I would look at this is because it seems like you addressed everything in the cooling system.

If this doesn't pan out, your only option may be putting a high speed electric fan on it or even a pusher fan in front of the radiator. However, before going there, get an infrared temperature meter and check all around the engine and make sure you don't have a restriction.

Let me know what your timing is set at and we can go from there.

https://www.2carpros.com/articles/how-to-use-an-infrared-temperature-meter

Yes. This is exactly correct.

Here is a video that takes you through the entire process. They get very detailed but the important thing you need to follow is how to set the light up, how to check the base timing (idle/initial), then how to adjust the timing by moving the distributor.

One important thing when setting your base timing is to remove your vacuum line from the distributor. This is the vacuum advance and will effect your setting so you want this unhooked.

Once you set your base timing, the advance will take care of itself. I suspect that your base timing in low which is causing your total timing to be low which is why you are overheating while driving down the road.

There are video on the internet of guys setting timing on your engine but they were pretty amateur so I didn't want to recommend them on how to do it. However, feel free to look at them to show where all these components are on your specific engine.

https://youtu.be/UYGU7mTwsZc

Hopefully this helps. Please let me know if you need more assistance with this and I will help how I can. Just a tip. If you don't feel confident doing this, then I wouldn't attempt it by yourself. You can probably find any senior mechanic and ask them to show you how to do it and I am would think they would. They may charge you to do it but I am sure they wouldn't mind teaching you if you ask. At least, I know I would and I am sure there are others that will as well.

Okay. These are a little harder to figure out because they happen when driving down the road so checking it out is clearly not that easy.

What we need to do is, get it hot (before it vapor locks) and use an infrared temp gauge and see where you have a hot spot or if it is even all around the engine and cooling system. You will want to measure the engine block and cooling hoses and radiator.

Normally, these issues are caused by a restricted radiator or kinked hose. Basically, when the engine gets hotter if the coolant is restricted, it can't cool the engine quickly enough. At a lower RPM it is okay.

Let's check and see if you have a hot spot and go from there. Thanks

https://www.2carpros.com/articles/how-to-use-an-infrared-temperature-meter

Okay. We need to go back to how the engine is tuned and running. The engine may be running well but if the cooling system cannot keep the engine cool then it is most likely tuned to rich. I mentioned it earlier but I fight vapor lock on my father in laws 1956 Mark ii. The cooling system is not the issue, but when I bump the timing up a little it runs better and cooler.

Where is the base and total timing set? I know you had it checked but I am wondering if you can advance the timing and see what happens with the vapor locking?

I get how it can be frustrating because you have gone through the entire cooling system but again, I don't think it is a cooling system issue.

At this point, the only other thing you could do is add a pusher fan on the front of the radiator to keep the system cooler.

What RPM are you running at when the temperature gets that high?

Okay. It depends on the type of shift kit. Normally they don’t change shift points they just make the shift points more firm.

Let me know the RPM and we can go from there. Thanks.

That is why you are overheating at that speed. That is too high for a cruise speed. The water pump can’t move the coolant fast enough to keep up with the heat generated from that RPM.

What gearing do you have in the rear end?

Unfortunately you may to to reduce the gearing so you can be at a lower RPM at higher speed or drive slower.

You nailed it. Unfortunately, driving slower is probably going to be the only option until you can locate another set. The fortunate thing is you probably won't get any speeding ticket.

There is nothing wrong with the rear end. It’s just causing you to run at a higher RPM when going 70 MPH. It is doing what it is supposed too.

Running at a constant 3000+ RPM the cooling system can’t keep up. When running at a slower speed the RPM is lower and it doesn’t overheat. This is why the vehicle wasn’t built with this high of a gear.

At this point your only options in my opinion are to drive slower so the RPM is in the range it would have been with the smaller gear. Or put a pusher fan on the front of the radiator to try and move more air to cool the coolant faster so that you have colder coolant going through the engine at that constant high RPM.

Yes it will if it is clogged up how does the coolant look? This guide can help:

https://www.2carpros.com/articles/engine-overheating-or-running-hot

Please run down this guide and report back.