Oil cooler for a 1967 Eldorado?

[67_Eldo]

Have any of you 429 owners installed an oil cooler?

I got a chance to wind my 67 Eldorado out on the Interstate yesterday. It was a perfect, sunny day in the low 80s (degrees F). As I cruised along at around 75 MPH, my temp gauges began to rise. One of the gauges is the original and the other is spliced into the upper heater hose. The heater flow is controlled by a Vintage Air electronic heater valve that I opened all the way to maximize water flow.

After about 10 minutes, the original gauge was between the half and three-quarter mark while the other gauge was indicating between 220 and 230 degrees F. This is with the air conditioning off on a relatively cool summer day. That's too hot an engine temp in my opinion.

The car can putter around town and idle all day and not get hot. But apparently if you keep the RPMs at around 3000 for a while, heat saturation sets in and it can't get rid of the hots fast enough.

I haven't had a chance to check the timing since I got the car back from the top repair. But in early May, I'd set the timing to 5 degrees BTDC. Everything in the cooling circuit is new: the original radiator was re-cored with copper (at considerable expense), new water pump, new thermostat, new hoses, new fan clutch, new radiator cap, new everything. I've even installed an overflow tank, which had accumulated some coolant by the end of the day. I'm running 91 octane non-ethanol unleaded gas.

Then it occurred to me: My Eldorado is perhaps the only 1967 model in the world in which you can drop the oil pan without moving either the engine or transmission. For reasons I've described in an earlier post, my oil pan was "re-engineered" a while back. As a result, the engine lost about one pint of oil capacity.

I wouldn't think that the loss of one pint of oil would mess up the 429s ability to cool itself, but now I'm thinking that, given the way the 429 evolved -- being the "maxed out" 390 -- maybe the absence of a pint of engine oil could push the engine's capacity to cool itself over the limit?

Have any of you added aftermarket oil coolers to a 429? Some of the literature claims a 60-degree (F) improvement in cooling! Does that square with your experience?

[TJ Hopland]

Is there room for a larger oil filter?  Back then many of the oil filters used the same tread and gasket diameter so with a little searching you can often find longer or larger diameter ones that will work if you have the clearance for them.  That would be an easy way to pick up some capacity.

[67_Eldo]

Good point!

It looks like I have some wiggle room. I'll take a peek at larger oil-filter options.

Thanks!

["Cadillac Kid" Greg Surfas 15364]

If my numbers are correct, 75 MPH should be about 2700 RPM, typically within the range of good oil return for these motors.
  FWIW I ran my '66 429 at 75 here in southern Texas where it is always hot and the AC is never off all the time without overheating.  My suggestion is to look for the source of the overheating before you start "fixing" things that might not be the problem.  Radiator, collapsed hoses, bad vacuum advance or improper mechanical advance, water pump cavity in timing cover eroded severely, and the like
Greg Surfas

[67_Eldo]

Since I'm without a mechanical speedometer at the moment, I generally estimate my speed in 500-rpm increments. I know that my GPS speedometer in my iPhone told me I was doing 95 for a short while while I was demonstrating 1967 Eldorado performance to the pilot of a beat-up Nissan pickup, but that didn't seem to change the rate of heat build up. :-)

Once my lower-back muscles have repaired themselves (they popped while I was wiggling around in the trunk installing speakers last weekend), I intend to review the major mechanical players again, particularly the vacuum advance and the radiator.

But as I mentioned, everything in the cooling system was replaced a year ago. I took pains to make sure the timing cover was OK.

Also, my oil pan is no longer "stock." It lost around a pint's worth of capacity when the mechanics who had forgotten to replace the rear-main oil seal (while the transmission was out of the car!) figured out a "clever" way to make oil seal replacement "easier." So I think the effect of lost oil capacity still may be in play.

I did find a monster Fram filter (the HP2) that would fit, so I might try that in addition to reinspecting the usual suspects.

Thanks!

[wrench]

First thing I would do is check the calibration of the after market gauge with an infrared thermometer.

Once I have quantified the gauge error, I would then go after the problem if it isn't gross gauge error.

It will also help as a baseline for any repairs.

Does that thing have a viscous clutch fan?

[67_Eldo]

Does that thing have a viscous clutch fan?

Viscous?

It darn near took my finger off!

<bada bing!>

In all seriousness, yes, it does. It was replaced during the Great Eldorado Financial Depression of 2017.

I have seen new fan clutches go bad too, so maybe this one is no longer a fan of being a fan (in the clutch)?

Another option I was thinking of was to add an auxiliary electric (pusher) fan in front of the condenser/radiator. But then I was thinking that an oil cooler would probably have much more impact.

I have a very cheap infrared thermometer that I was checking temperatures with before I knew there was a problem (that is, just driving around town below 60 MPH). The three gauges were not in exceptional alignment other than the fact that they all indicated increased or decreased temps together.

BTW, I also have a new voltage regulator and the "original" temp gauge I have is one I just received from eBay because I don't trust the gauges I already have. It is Gauge City around here!

[67_Eldo]

At the beginning my hunt for the source of excessive engine temps, I've made a discovery: Rebuilt distributors for 1967 Cadillacs have become more difficult to find than they were just last year.

The distributor and the steering box are the only two subsystems under the hood of my car that have not been either massaged or replaced in the last two years. Although the pieces inside my distributor seem to respond properly, the shaft is a tiny bit wiggly. I figure I might as well replace it to remove another variable.

I looked into doing this last year, but back then I didn't think I had a distributor problem.

Apparently since that time, parts manufacturers and remanufactures decided that repairing old Cadillac 429 distributors is not a worthy business option. The parts are still listed in many places. But when you go to add one to your basket, the popup says "Unavailable forever."

There are some companies, such as MSD, that sell their "billet" distributor replacements. In the case of MSD, I'd have to buy their whole system at around $700. They also say that the distributor for that 472/500 will fit into the 429, which I find hard to believe.

Does anyone have a good distributor "lead"?

[Scot Minesinger]

Your exhaust is restricted.  A restricted exhaust makes a car overheat or run too hot on the highway, but not at lower rpm's around town.  This happened to me on a 1972 Eldorado where the  resonator still enjoyed the nice aluminized outer outer finish, looked still good.   

The internals of the resonator collapsed and created a much more restrictive system.  You can check this out perhaps by a vacuum gauge on intake while running higher rpms, the gauge should gradually lower the reading.

I had read about this before where a 1966 Thunderbird ran great but would overheat or run too hot at higher rpm on the highway.  After eliminating heat riser, water pump fan shroud, timing, radiator, water pump and the like on the 72 Eldorado this was about my only option left and I sawed the resonator inlet and removed the resonator.  After that the car had no issues.  Replaced it with a good resonator and all was wonderful.

This is a common problem with low use and low quality exhaust parts.

[67_Eldo]

Interesting idea. Now I have one more thing to check! :-)

Thanks!

Once this heating problem is solved, I think I'm still going to add a small oil cooler to the location right behind the front license plate. Then I'll make a mini-"grille" that bolts into the current license-plate opening.

Heat is the most vile automotive enemy! If my thermostat opens at 180 degrees, I want the engine to thereafter operate at 181 degrees. :-)

[That's also one reason the car will remain white: It will reflect Ol' Sol's rays more diligently.]

["Cadillac Kid" Greg Surfas 15364]

Your engine and it’s cooling system was designed to run at 195 degrees. Just installing a lower temperature thermostat will not lower the temperature. In fact (without the explanation of LMTD factor in heat exchangers) with a 180 degree stat. heat transfer at the radiator is reduced just about 18% from design, resulting in heat build up in the motor AND a rise in coolant temperature until equilibrium is reached. With your AIR. Equipped motor that should be 195 degrees as designed.
Greg Surfas

[35-709]

A 180 degree thermostat starts to open at 180 (+or-), it will not be fully open until 15/20 degrees later, which is just about where you want to be.

http://www.stant.com/index.php/english/products/consumer-products/thermostats/faqs/

[Scot Minesinger]

Greg is right a thermostat replacement to a lower temperature will do nothing, and in fact be worse.  The thermostat maintains a minimum temperature, and does not restrict the upper temperature engine operating limit.  If this were true, we would solve all our over heat problems by replacing the thermostat. 

Further adding oil coolers and the like that were not factory designed (the factory spent millions in engineering in 1967 to develop a trouble free luxury car) are not always going to help.  Check your exhaust, sounds like the issue.

Good luck,

Scot

[67_Eldo]

I'm going to leave the thermostat as it is (at 180). I just want to make sure that the temp does not go much beyond the minimum necessary to operate.

Back in the day, I had a 1966 Austin Mini Cooper S 1275 GT that was also an ex-race car. It ran a 3/4 cam. With the radiator blowing directly into the driver's side wheel well -- one downside to the Mini's crude transverse-engine design -- I had to run the heater full blast on the 100+ degree summer days to keep the temp gauge out of the red ... until I bolted a big ol' oil cooler to right side of the grille opening.

The Eldorado, I'm sure, does not require the magnitude of heat dispersion that the Mini did. But I want to make sure I stay on the cool side.

Thanks!

[Scot Minesinger]

Race cars need oil coolers, several muscle cars had an option for them.  Just got my "Muscle Machines and there is 429 Ford engine with an oil cooler article.  I bet Greg might have an engine oil cooler on his 1973 modified Cadillac.

["Cadillac Kid" Greg Surfas 15364]

Have any of you 429 owners installed an oil cooler?

The answer is in almost all cases with literally hundreds of thousands manufactured and successfully operated: NO. If your car is ACTUALLY overheating something is wrong.
Greg Surfas

[Scot Minesinger]

Agree with Greg 100%

[67_Eldo]

If your car is ACTUALLY overheating something is wrong.

I generally agree, but that doesn't (practically) take the passage of Tine into account.

I'm not one of those guys (like some of these body-shop folks I've been dealing with) who give me a hard time about the rusted top, saying "These GM cars were engineered to last only five years anyway. Why waste time? These cars are disposable."

On the other hand, 60s-vintage Cadillac metallurgists weren't too concerned about how heat transfer in the cooling passages or via the oiling system was going to change in 50+ years.

So I have a car whose cooling capacity may have been diminished by corrosion in the cooling passages (which are clustered on the upper half of the engine) or diminished by a reduction of oil capacity (in the lower half of the engine). Neither of these problems is so "wrong" that it is worth removing and disassembling (and replacing?) the whole motor.

Perhaps the heat buildup in the lower, oil-cooled part of the engine needs that extra pint that it had once upon a time? I don't know. But I'm not going to pull the engine and replace the oil pan to find out.

If the ravages of Time can be overcome (and possibly improved upon) by the addition of a $100 oil cooler, that may be a more practical bargain.

I gather that nobody on this board has ever felt the need to install an oil cooler. That's OK. I'll see if I'll need to blaze a new trail once I can check my current distributor with a new/remanufactured one.

Thanks!

["Cadillac Kid" Greg Surfas 15364]

We are all anxious to hear how that works out for you.

Greg Surfas

["Cadillac Kid" Greg Surfas 15364]

I generally agree, but that doesn't (practically) take the passage of Tine into account.
On the other hand, 60s-vintage Cadillac metallurgists weren't too concerned about how heat transfer in the cooling passages or via the oiling system was going to change in 50+ years.

I'm Sorry, but I can't let that go un answered.  Robert Templin would be fuming in his grave at the arrogance of that comment if I did not respond.
In the 60's Metallurgy WAS THE MAJOR FACTOR ION ENGINE DEVELOPMENT.  Isotopic analysis of the wear of each and every component in these motors was used to determine the exact wear  points and correct as required to develop an engine that was good for 1/2 a million miles.
The acceptable wear on the cylinders was stated to be 0.001 per 100,000 miles for 300,000 miles at which the wear would cease.  This was not by guessing or computer simulation but by actually  physically testing.
The assumption was that the motors would be maintained as directed and not fooled with.
Cooling systems were designed with a safety factor of something like 100% to allow for the expected surface condition changes.
Okay Bob, I'll stop now Ive said "Your" piece.
Greg Surfas