ALSO: T-Bird Service recommendations
And for more great information: Link to Gil’s Garage on the CTCI website
BATOC members share Tech Tips
VALVE COVER GASKETS
By Bob Koltvedt
The author recommends using the cork gasket that is sold by the Thunderbird parts suppliers. You can also get the same cork gasket from NAPA or other good parts stores. Some stores sell a rubber
gasket, but it is much harder to install properly. When you install the cork gasket, you can use some RTV placed in the groove of the valve cover. You do not need to use a lot, only enough to help hold the gasket in place. I do not recommend that you use any adhesive. Gasket adhesive will work, but it will also make it difficult to save the gasket if you need to remove the valve cover again for valve lifter adjustments. To ensure a good assembly, I would also use some masking tape to help hold the gasket. You can loop the tape around the gasket in two places along its length – on both the top and bottom of the gasket. Loop it so that two or three inches of the tape will extend outside the cover when you put it on the engine.
So if you were paying attention last year I installed a new set of disc brakes on the front of our 56 Tbird. I was asked the other day if I was happy with the set-up after having it on for a while now. I have to say I have some mixed feelings about how they work. On the one hand they do work much better than the drums that we had. It was like wrestling an alligator in an emergency braking condition before. No more. They brake in a straight line now. That alone was worth the effort. But…I installed a stock divorced power brake booster at the same time. Turns out the booster may work for standard drum brakes but it doesn’t actually build enough pressure to operate disc brakes properly. I think the disc required something like 1500 psi to accommodate disc and the stock booster only puts out somewhere around 800-900. Might be enough as-sist drums but not enough for the disc. Apparently there are other boosters of the same design that were installed on big trucks that put out more pressure but I’m not sure if they even made enough for the disc. I’m still looking into it. Meanwhile I don’t really expect to ever have the brakes of a modern car but I’m happy if I’m able to make it a little safer to drive.
All in all I’m happy I did the upgrade.
(see the May 2016 newsletter for the beginning of the story and the June 2016 follow up)
A TECH TIP FOR SUMMER
Every Summer everyone starts freakin’ out about overheating. Unfortunately, there are a lot of “Wives-Tale” beliefs and solutions that get thrown around that could cost you a lot of money with no resolution.
The gauges and sending units in these cars are very sensitive and are matched pairs and the sending units cannot be replaced with just any parts house sending unit. Unfortunately, after 50 years, there is a high probability that it has been replaced with one from the local “Grand Auto” store and is not correctly matched. As a result, most Thunderbird temperature gauges are woefully inaccurate.
Therefore, before trying to solve what you believe is an overheating problem with one of the many “Fix-All” solutions – be absolutely certain that the car is actually overheating and that it is not just the gauge reading wrong. How do you know? Well, there are several good indications and one way to actually prove it.
First, I strongly urge anyone who thinks their car is overheating to spend $29.00 (or less) to prove it. Install a mechanical temperature gauge from your local parts house in less than 15 minutes and see if you are, in fact, overheating. You may (and from my experience) probably will be surprised. I have seen many cars with pegged gauges and owners who were totally freaked out that were actually running at a perfect 180 degrees.
Second, be aware of the two most common signs of real overheating. Obviously steam pouring from your engine is the first accurate sign, but before that happens an engine that is getting hot and close to overheating will start to miss and PING even under the slightest load – like leaving a stop sign. If you hear pinging AND your gauge is reading hot you can be pretty certain you’ve got a cooling system problem. But conversely, if there is no steam, no sudden missing and no pinging, the car is probably NOT overheating. Put on the mechanical gauge and see what your engine is really doing before buying all the fancy fans, pulleys, baffles, etc. None of those items will correct a mismatched inaccurate gauge.
Try it – your car may surprise you.
A LITTLE OIL LEAK TECH TALK
As most of you know, a couple of years ago I spent a couple of long weekends installing, among other things, a new rear main seal in my 10,000 mile old engine. This was necessary due to a very unusual, almost instantaneous, but “Complete Failure” of the rear main seal that was there. This is not going to be an article about that replacement of the seal, per se, but rather a few related random thoughts and things to watch out for if you have leaks or chose to tackle this job in your own car.
A Few Overall Thoughts
While you will hear a great deal of “Water Cooler Talk” about replacing the seal with the engine in the car and the people who offer to do this job for you (with no guarantees) … I would not suggest this approach. Why?
1) We are all too old to be lying on our backs underneath a car.
2) While it can be done, removing the pan with the engine in the car is NOT an easy task.
3) Working the new seal in, particularly the original rope type, is really frustrating and hard to be sure of once you’ve actually accomplished it. Anybody remember the old Chinese Finger trick for doing this?
4) Chances are very good that the new seal will not be “seated” correctly and will still leak … and that, my friends, REALLY SUCKS.
5) Getting the pan OFF is tough … getting it back on with the new gasket intact is REALLY tough.
6) Nothing else gets fixed in the process.
7) You can pull the engine and do it right …and fix a whole lot of other things while you’re at it in about the same amount of time.
Thoughts On the Seals Themselves
I have used all three types in this engine … Original rope, modified Chrysler 318 rubber type and now the “New” Silicone seal that is made for the “Y” block … and here are my ratings of each. The original seal worked and still does work very well with two caveats. First, it MUST be installed correctly. This is almost impossible from under the car, with the crankshaft still in. And second, with crankshafts that have hundreds of thousands of miles on them and maybe several “Grinds” and polishes on them, the original oil groves that aided in throwing excess oil away from the seal have generally disappeared. As a result, even a properly installed original rope seal will have trouble.
My experience with the Chrysler seal has been less than ideal. It requires a little “surgery” before installation and unless this is done perfectly it doesn’t quite seat properly. As a result it is a little tight on the shaft and causes excess heat to build up on the seal. For me, this caused the seals’ edge to “Weld” itself to the shaft and ultimately fail. This didn’t happen immediately and the seal worked, albeit poorly, for about 2 years. But overall this was Not Good.
The new seal fits VERY nicely with no needed surgery and just “felt” right. You just know when something feels right. It has now been in my car for 5 or 6 years and virtually not a drop to be found. A very nice site.
But Here’s A Major Tip
Many rear main leaks are misdiagnosed and are actually Valley Cover gasket failures. The oil leaks from the valley cover and typically runs to the back of the engine, around the base of the distributor and down around the rear of the engine to ultimately drip off of the bottom of the bell housing – exactly like a rear main seal leak. This is very difficult to see since most engines have a great deal of grease and oil built up and it becomes hard to distinguish the multitude of leaks. But check this carefully before assuming that it is coming from the rear main. Should you determine that your leak is, in fact, the valley cover, here’s a little more advice.
The valley cover is a VERY tight fit when trying to get it past the “tabs” of the intake manifold seating surface on the heads. There are actually notches in the valley cover designed to let it fit between these tabs on installation but it doesn’t always fit. Unfortunately for you, this may have caused some back yard mechanic to force it past the tabs and “tweak” the valley cover. Combine this with mechanics who tend to over-tighten the covers’ bolts and these two events, in many cases, have caused the valley cover to become twisted and “untrue”, making for a horrible gasket seal. This is not too tough to spot by simply laying a straightedge along the sealing surface of the valley cover and noting how flat (or not) it is. Is each side “straight” AND does the valley cover itself sit flat … not twisted or torqued in anyway. If it is tweaked, get a couple of long straight edges and do a little blacksmithing to get these surfaces true, straight and flat. If you don’t, the new gasket won’t seal any better than the old one. (No matter how much gasket sealer you use)
Upon installing the valley cover be VERY careful not to tweak or twist it. You can actually grind or file off the tabs on the head a little, and / or file out the notches on the valley cover a bit (not too much) to allow the valley cover to drop in without tweaking it. Of course, if you are grinding the heads down on the car, be sure to protect the internal areas from the grinding dust and shavings.
TO QUARTZ OR NOT TO QUARTZ ?
If you have considered converting your T-Birds clock to a quartz mechanism, you may not need to if you understand your original clocks short-coming. You see, unlike later model automotive clocks which worked with a spring loaded mechanism that is “cocked” by an electro-magnetic relay, the 1955 & 1956 T-Bird clock is a constantly running electric motor. This means two things that quickly turn into several other things. First it is a constant drain on your battery that will easily take 20 – 25% of your battery’s charge in as little as 2 weeks, and this can make starting your little jewel a bit tough…particularly in a 6 volt system that needs every ounce of charge to start. This quickly cascades into two more things. First, this constant draining and then recharging of the battery is very hard on it and will shorten the batterys’ life significantly. Second, and the very point of this tech tip, is that the resulting decreased amperage present in the battery as it discharges is the biggest enemy of your delicate clock. After only a year or so of a poorly charged battery, your clock will come to a grinding halt. So, the moral of the story? Unless you are driving your car on at least a weekly basis, be sure to either keep that trickle charge going or disconnect the battery. You’re not only ensuring that you won’t have a dead battery, but you are preventing damage to your battery and saving yourself a pricey trip to the local clock shop or conversion to quartz.
DON’T BELIEVE EVERYTHING THEY TELL YOU !
An often overlooked or little known cause of hard starting (not sluggish cranking, but not firing adequately) is insufficient voltage at the coil during cranking. Well, here’s a little tip that may save you the often misdiagnosed carburetor rebuild. Because of the T-Birds somewhat strange and misunderstood coil resistor circuit, your car actually runs on only about 8 volts after the engine is started. However, during cranking the starter relay on the firewall is supposed to take the resistor out of the circuit and supply full battery voltage to the coil, thus giving the engine a little extra kick for starting. The lack of this extra voltage will manifest itself as the engine “firing” but not really taking off with umph. Many mechanics will convince you that this is a carburetor problem…either flooding or starving and sell you a rebuild. If this sounds familiar, put a simple volt meter on the battery terminal of your coil (or the “I” terminal of the starter relay) and make sure that you have battery voltage (usually a little less than 12 volts) present during cranking. If not, your starter relay is most likely “not relaying” correctly and needs to be replaced.