1965 Thunderbird project thread

Instead of sharing multiple posts I figured I would start this thread to share my progress, advice and questions in one place.

A few weeks ago I trailered home this 1965 Thunderbird hardtop with a 390. I was told it ran recently but had been sitting; I was able to crank the motor and it would fire momentarily with starter fluid.



This is what I have done so far;

1. Changed oil and filter.
2. Dropped tank, cleaned out and cleaned fuel lines.
3. Added Holley Demon 625 carb.
4. Replaced distributor cap, coil, condenser, arm and points.

With all this done she ran good (albeit at a VERY high RPM) but there was a knocking on the passenger side, and bad smoke. Opened the cover to discover this little beauty.



I was able to manipulate the valve, so it isn't stuck right now. I just bought a leak-down tester and plan on checking things out when the weather warms back up.



Yesterday I spent 5 cold hours (just me and a propane heater) stripping a donor 66 Thunderbird I found. I hope the interior parts interchange! Mine isn't bad, but this one was better and black instead of red.





Other than that just painted up the covers the other day.



And that is where I am at!
 

Hadderz

Active Member
This is great, it looks like you are starting with a decent, straight looking car! Also, the image of inside the rocker cover looks quite clean so the original owner must have done oil changes lol! Following with interest.
 

64ZCODE

Well-Known Member
Looks like a bent pushrod? The valves on these FE engines tend to stick if not run for awhile. Before firing it up again would be well worth applying penetrating oil to the valve train and working it to loosen things up.
 
Looks like a bent pushrod? The valves on these FE engines tend to stick if not run for awhile. Before firing it up again would be well worth applying penetrating oil to the valve train and working it to loosen things up.
Someone mentioned that. Is that a matter of dumping it straight down into the valve spring areas and maybe manipulating the valves manually? Do you think it would be worth trying this before tearing further into it? Replacing the rods is pretty easy.
 

64ZCODE

Well-Known Member
Yes it would be well worthwhile to rule out sticking valves before going further. If you have more bent pushrods, it would distort results of a compression test. Check the web, there is good information there on FE engine bent pushrod issue and how to resolve. Good luck!
 
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Yes it would be well worthwhile to rule out sticking valves before going further. If you have more bent pushrods, it would distort results of a compression test. Check the web, there is good information there on FE engine bent pushrod issue and how to resolve. Good luck!
Gotcha. I already pulled the other rods on that side and all are good, so I just had to buy the one.
 
Another question guys;

Where do all the vacuum lies under the hood go (390 motor)?? They were all unplugged when I bought it. I already figured out the one that goes from the carb to the distributor vacuum actuator (which itself was bad). But where do the others go or should be plugged to? Both valve covers also have fittings that are hooked to nothing.

Thanks in advance!
 

64ZCODE

Well-Known Member
You should get a manual with a good diagram, also check out Thunderbird Ranch website for technical diagrams. '64s vary depending on how equipped. Basics are manifold vacuum connection to the brake booster, a line from the metered vacuum port on the carb to the distributor advance, and a line from manifold vacuum into the cab of the car to actuate the vacuum emergency brake. Some cars have vacuum can reservoirs as well as vacuum actuated ventilation controls. Short answer: it depends.
 
Thanks much, I have been digging into it.

One question that should be pretty standard though; both of my valve covers have openings that currently go to nothing. The driver's side has a vented and ported cap which I believe is actually for a Mustang, and the passenger side has a rubber grommet with nothing in it.

If I am reading correctly one of these openings should house a PCV valve, I believe it is the open rubber grommet. Is this correct? I have also read that the PCV valve should run to a port on the intake manifold, and that the opening on the driver side valve cover should lead to underneath the air filter assembly.

Am I on target? Here are pics of the motor as I got it and what I have after painting.



 

64ZCODE

Well-Known Member
Hi there. Grommet hole in the passenger side valve cover is indeed where a PCV valve was inserted. On my '64, there is a fitting at the rear end of the crankcase with a solid pipe that runs to the PCV valve which is located on a bracket behind the carb. It's located in the upper left corner of the picture below. From there, a rubber vacuum line runs to the intake manifold. This doesn't appear to be how your's is set up, but maybe it's been monkeyed with. Check to see if that fitting on the back of the crankcase is there or not. If not, you could get a new PCV valve, plug it into the grommet hole, and run vacuum hose to the intake manifold. Crankcase ventilation is very important.

1580962176785.png
 
Quick update with videos;

Decided I wanted to do the leak-down test with the motor warm, so I just finished putting it back together and running it. Started right up, but I want to figure out why it is idling so high before I do anything else.

Same symptoms as before though. Lots of white smoke from the passenger side exhaust and moderate amount from the passenger side valves. The driver side doesn't seem to some at either place. Thoughts?

I did spray the valves with penetrating oil as well as spraying some into the cylinders, and I fed the carb mystery oil while running an then shut it down.

Here are some videos, thanks in advance!

Valves.

Exhaust.
 

64ZCODE

Well-Known Member
Hi there. The videos are marked as "private" so I wasn't able to open them up. However fast idle could be a vacuum leak or perhaps the carb is dumping excess gas into the intake manifold. The latter would be consistent with white smoke at the back (rich running condition). Sounds like you're making progress!
 
I just fixed the videos, sorry about that!

Progress indeed! I tried working on the vacuum situation today. Like you shared earlier I did have that metal valve that the PCV valve goes into (thanks!), though it was completely detached and hanging loose. It was rigged up with some weird hard piping, so I replaced the hoses and ran it as I believe yours is. Here is a pic.


There appears to be another vacuum port under that. I have no idea what it is for and it was wide open, so I plugged it off.


I thought maybe a throttle adjustment would help with the idle, but the carb is already as far closed as it will go and it is still idling high. The zip tie is because the throttle adjuster arm is out of thread, I am going to have to chop/weld it or get a new one.


Admittedly I have made NO adjustments to the carb since installing it. There is mention of a throttle adjustment screw behind the choke assembly, and I did find it, but darn it is hard to get to!
 

64ZCODE

Well-Known Member
I think how you set it up will work but it is different than the stock setup. Pic below is of the stock setup. The PCV valve is in the middle of the picture frame. The hose coming off the top of the valve connects with the fitting at the back of the crankcase. This is where the crankcase fumes will be pulled from. The hose angling down and to the left from the PCF valve connects to intake manifold vacuum. In my case, I have a carb spacer and the manifold vacuum port is there:


1581123180293.png

In this pic, where is the black hose running to? I'm thinking that if you're scavenging fumes from the valve cover, you may need to plug this line:

1581123582159.png

With it hooked up as you have it, what are you seeing in terms of smoke out the back? also wondering what carb you are running.
 
Oh... so the odd bracket that I have bolted where the throttle linkage is is actually the PCV valve itself? I bought a PCV valve that I believed sat down into the passenger side crankcase cover. That is what I have the hose at the top of that part going to, and the bottom half going to the spacer between the carb and intake manifold.

The hose you ask about goes nowhere, I have it blocked off because it was left open when I got the car. So if I am understanding what you typed the PCV (on the bolted down bracket) goes between the carb spacer and the crankcase? If that is so I suppose I can unblock that port and run the hose to that instead of the valve cover.

And if all THAT is correct what is the purpose of the rubber grommet atop the passenger side valve cover?
 
And sorry, to answer your last question, the driver side exhaust seemed good but the passenger side was thick white smoke that did not leave a residue on the cement.

The carb is a 625 Holley Demon
 
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Well here is where I got this weekend. Was still having the high idle issues, so I started looking for vacuum leaks. I found a big one behind the carb, ended up being the wrong carb spacer gasket that didn't include a section that was to seat the recess for the PCV valve, so the gasket bubbled and was sucking air.




Had to order a new gasket which arrived today.



It is running much better now, though still idling a bit high.

Here it is right after start up in cold weather.

This is after about 5 minutes of warming up.
 
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