am i running hot, or am i the king of neurosis?

generally speaking the water temp hovers around 90, but if i've been in traffic for a while (driving around manhattan whenever i can!), this is where it creeps up to...anything to worry about ?
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That's where mine used to run until the fans came on and then it dropped a bit..... for 15 years of ownership.

 

Phil, attached is a picture of the dials in my car after a fairly long continous run. On shorter more sporty country lane drives the oil and water temperature dials generally point vertically down. My water temperature needle does not go beyond this, even when the fans have kicked in while car is sationary. As I am sure we all know, we should not take these dial readings as absolute measurments and also probably not relative to each car. A temperature probe is the only way to meaningfully compare. However, useful to know what we see on the dash, and also to monitor changes in the same car.

Kevin
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Phil - your temperatures do appear higher than design specification. Under normal operating conditions (hot day, idle traffic), the gauges and sending units are designed to position the needle in the vertical position (for ease of identifying anomaly).

As Dave suggested, inferring absolute accuracy from these units is unwise. However, that yours does sit vertically under normal driving conditions suggests that your cooling system does not tolerate perturbation.

Hence, if it were my car, I would do a bit of investigation. You likely know what to do....
1) Bleed system
2) Make sure both fans come on at appropriate temperature - AND SPIN IN THE PROPER DIRECTION TO BLOW AIR INTO THE RADIATOR, not out the front of the car.
3) Drive car down long hill to see if temperature rapidly cools (suggesting that you have adequate water pump output).
4) Consider thermostat failure or partial failure.
5) Bleed system again.

And if these steps do not identify a cause, consider a recheck of ignition timing (advance runs hot), carburation (lean runs hot), and finally radiator efficiency. Borrow an infrared thermometer and measure the difference in temperature between the radiator intake pipe and radiator exhaust pipe. You should see a 30 degree differential, at least.

Jim S.

 

thanks for all the help...here's another bit of info-once i'm out of traffic, and drive for a decent stretch uninterrupted, the temp drops down to the vertical position..does that tell anyone anything?

phil

 

Sounds normal to me if it drops like that.

Dino wants to stretch its legs!

I suppose if you worry you could do a good coolant flush and put 308 fan blades on.

 

That your temperature approaches normal when moving (and presumably not demanding much of the engine) speaks for 1) adequate water pump flow (output), adequate flow through the thermostat, and adequate flow through the radiator. However, the thermodynamics of the engine in traffic should not create significant insult to steady state. Do you suppose that any car manufacturer, Ferrari included, would knowingly design a car to overheat in traffic?

In fact, the thermostat, water pump, and fans comprise a feedback control system to maintain operating coolant temperature at a steady 185 degress (thermostat threshold). As the temperature rises, the fans come on to lower the temperature of the coolant exiting the radiator. When coasting down a hill, the airflow over the radiator would cool the liquid below 185 degrees, leading to the fans turning off and the thermostat closing to impede flow through the radiator. Transients will occur, as when loading the car up a hill, or coasting down a hill. For a few moments the temperature will deviate from the norm as the "feedback control system" seeks the 185 degree point. However, your description implies that when in traffic, the system cannot achieve a normal steady state.

Either the thermostat is not fully opening, the fans are not fully functioning, the radiator is not fully flowing, or the engine is producing too much heat (unlikely at idle - traffic conditions). This is more likely a heat dissipation issue than a heat generation issue.

Sorry to ramble. The presence of a thermostat implies that a normally operating system has excess capacity to cool the engine. That is, without the thermostat, the engine would run at too low a temperature. Of course, the thermostat is perceived to be primarily a warm-up device, to hasten warm up in cold climates. Indeed, this is one of its functions. The other is to maintain a steady state temperature (185) to provide some predictability of tolerances, oil viscosity, etc., and to provide for the production of work.

Thermodynamically, the internal combustion engine is a heat engine. It converts heat to work (through adiabatic expansion of gas against a piston crown). Every degree above ambient that the engine achieves is wasted energy. If perfectly efficient, the engine would be cool to touch, all of the heat of combustion being converted to work. On the other hand, our attempts to force the engine to run "cool" with larger radiators, better fans, water wetter, etc., is false economy, so to speak, for when the iron (or aluminum) block is cooler than the combustion temperature, some of the heat of combustion escapes to heat the engine. If the engine could run at combustion temperatures, then there would be no transfer of heat to the parasitic thermal mass, and all of the heat would be used to expand gas.

The ideal engine, therefore, either operates at ambient temperature, where there is no internal friction and all of the heat is converted to work, or it runs at 1800 degrees, in perfect thermal equilibrium with the combustion chamber, and as the gas is introduced into the combustion area, all of the heat produced is used to push the piston, and none is used to heat the block. Our current technology is closer to the latter. The thermostat setting represents a compromise between ideal thermodynamics and acceptable tolerances and oil function.

Simple stuff, really. The point is, if you ask me what time it is I will tell you how to build a watch. It's an engineer thing.

Jim S.

 

hi jim...ok, a series of enormously clueless questions to follow, so apologies in advance...

1) Bleed system-what am i bleeding, and how do i do it?

4) Consider thermostat failure or partial failure. any way of checking for this?

thanks so much

phil

 

Your question is not clueless...you want to see clueless? Read my previous post.

Bleed the radiator-coolant system.. If you have air trapped in the coolant system (anywhere), the air will potentially impede flow, take up volume that could have been used for coolant, or decrease the coolant to radiator surface area (thereby rendering the radiator less efficient).

To bleed the system, one must find the highest point. This is designed to be the bleed screw (valve) on the upper right aspect of the radiator.

Now here is the REAL way to bleed your system. It will require about 10 dollars and a trip to the hardware store. While the engine is cold, remove the bleed screw. Take this with you to the hardware store. Purchase about 15 feet (too much, but hard to add on later) of clear, flexible, plastic tubing, the kind that you would see in a fish tank or the like. Also purchase a plastic, conical, tapered fitting (nipple) that you can firmly press into the radiator threaded hole where the bleed screw sits. You might entertain wrapping the fitting with Teflon tape or black electrical tape, anything to improve the seal. The seal is not critical, only makes things neater (water not flowing down the front of your car). If you are really industrious, I am sure that you can find a brass threaded fitting with one end that you can slide the plastic tube onto. One that has threads matching the radiator fitting. Envision one of the carburetor fittings that the fuel lines press on to, but with the proper thread.

Now park the car on a hill with the radiator up, or drive onto a few 2x4's or ramps. The higher the radiator relative to the engine the better.

Top off the expansion tank in the rear. Press the plastic fitting into the radiator bleed hole, and run the plastic tubing over the top of the car all the way from the radiator to the expansion tank. Coolant that escapes the bleed hole will be recycled back into the expansion tank. However, more importantly, you will see air coming out of the radiator (there should be none).

When you first start this process the engine is cold, hence the thermostat is closed and there will be no flow to the radiator. As head temperature rises, the thermostat will open, and you will begin to see coolant flowing out of the radiator, up the tubing, and back into the expansion tank. It will take some time (20 minutes or so), but eventually you should see a solid column of coolant in the plastic tubing.

Run the tubing on a towel (heat protection) over the top of your car. You want to create an obvious air trap high above the radiator/engine. Any air will be trapped in an obvious place. However, as you develop a continuous column of coolant, this air will be driven back into the expansion tank. This is okay as the tank is exposed to the atmosphere.

Several things will be learned in the process. First, is there a significant amount of air in the system. Second, is your water pump able to provide sufficient flow to push coolant out of the radiator, above the car, and back down. As you occasionally raise the RPM (2,000 or so), you should see the flow rate increase, and consequently air (owing to increased flow washing trapped air, or as a result of cavitation at the pump). Cavitation will occur in this situation because the system is operating with the expansion cap off - hence the pressure is atmospheric versus .9 Bar (or 1.1 Bar) above atmosphere. Cavitation (bubble formation on rapidly rotating surfaces vis-à-vis the water pump impellor) occurs more readily in low pressure systems.

Continue this operation until you are satisfied that no more air is exiting the radiator. Shut down the engine, ALWAYS keeping a column of coolant in the plastic tube so that as the system cools, no air will return into the radiator. When cool enough to allow, remove the plastic fitting from the radiator hole and reinsert the threaded bleed screw. Refit the expansion tank cap, and off you go.

One thought. Since you are expending this effort, you might entertain draining the entire system first, and replacing the coolant with distilled water and antifreeze mix, versus tap water. Cost little and prevents some degradation of the metal surfaces within the cooling system. To drain the system, allow the engine to cool, open the drain plug at the bottom of the radiator, collect the discharge, and then start the engine for a few moments.....without any coolant. This will drive any water in the pump out. If you really want to get dirty, crawl under the car and attempt to open the bleed valve on either side of the engine block. If you have never done this, I encourage you to first go to any mechanic or radiator shop and examine the standard block bleed valve. It operates opposite of what you might thing. Screw it in to open the valve. Once you see it you will understand. Most people break these taps by trying to unscrew the valve. (Kind of like a left hand thread).

Take note that the plastic tubing will become more flexible (soft-limp) as the temperature increases. No problem, simply account for this when you position it near the radiator so that it doesn't slip out of the bleed hole.

Have fun.

Jim S.

 

Jut read this thread and thought my car might be suffering from air locks as it often throws water out of the expansion tank after a spirited run. The temp though stays firmly to the left of middle. Did have a problem with a faulty thermostat so removed it. Drove car 20 miles yesterday and noticed puddle when I stopped. Temp normal. Will fit new thermostat tomorrow. Did try to bleed rad and no air came out only water so abit confused. Water level was 1 inch below rad cap which is new also. Is the car overheating but not showing it on the gauge? Am I the new king of neurosis??

 

i will defend my royal title vigorously sir

 

Like it or not, this is one of the most "engaging" parts of owning a Dino. When the temps rise, such as in Stop 'n Go traffic, then the driver is keeping track of the water temperatures. Soon the heat exchanger causes the oil temps to follows suit and it climbs. Next the fans kick in and suddenly you're also monitoring Amp discharge.

Phil, I believe you're now one of us as your senses are heightened and you become one with your Dino.

 

Scott, I do believe that you've caught the essence of Dino neurosis! The only analogy that comes to mind is a WW II Allied bomber limping back to England with half the tail shot off. It wasn't pretty, but damned if most of them didn't make it back time after time! I have never owned any other automobile whose various gauges I monitored more frequently than those on my Dinos. It almost requires the skills of a co-pilot! Fred p.s.: Don't forget the amp discharge when the so-called AC is on and revs aren't too high! f

 

Actually I stand corrected by an email. Second to Third gear on the twisties is far more engaging, but you get the general idea.

 

On hot summer days (90-100 F) here in SC, my water temp hovers right around the 195 mark in traffic and dips slightly below that on the open road. In the winter, with temps in the 60s, the reading is very close to what Daviekj shows in his photo at similar ambient (18 deg. C = 64.4 F).

 

One thing that makes a substantial difference in the cooling efficiency is the strip of foam rubber on the underside of the trunklid that seals against the top of the radiator. On my car, this had completely rotted away. When this happens, the air is no longer directed through the radiator and is free to take a path of less resistance over the top of it. The result is a significantly reduction in cooling efficiency. Home Depot, Lowe's, etc. sell a plastic foam strip that measures approx. 4" square. It's intended for sealing around window-mounted A/C units, etc., and is very inexpensive. It's a perfect fit for the Dino (needing simply to be cut to the right length), and even comes with double-faced tape for installation. I did my car about 3 years ago and it has held up perfectly. Summer operating temperatures were reduced considerably after it was installed. The worst part of the job was scraping off the remnants of the old, rotten foam.

 

When having paint work done on both of my Dinos, my painter purchased the correct material and, using the old foam on the underside of the front hood as a template, used an electric carving knife to make new pieces. He also made me a spare piece for potential future use. I never thought about the effect of a missing or deteriorating foam piece on cooling efficiency. Good point! Fred

 

Greetings Gents,
Since you've all zeroed in on the temp issue, as intended, I'm gonna deviate a bit. Looking at the previous two pics, it's interesting to note the differences in the layouts of the instruments (Though the seeming reversal of the speedo & tacho positions on Kevin's Dino may have been a Right Hooker thing, I found an inconsistency in photos of RHD cars on pages 56 and 62 of Ian Webb's book! Heck, I'll bet Kevin's clock & amp gauge are swapped, too ).

Hmmm, guess I better check mine....

I'm back: Yet another candidate for Correct Cluster honors.

So, to solve this mini-mystery, gotta go to the "PARTS CATALOG" (from car n. 02132) to find which is the REAL layout (at least for LHD cars)....

Nope: Catalog depicts an even different arrangement! Oh bother.

OK, I'll check out the "operating, maintenance and service handbook" (again, from car n. 02132) to see if we can corroborate....

Nope: A version that differs from that of the catalog and Phil's and Kevin's and...Wait! Not mine! Mine's as depicted in the handbook! Wow. I'm thinkin' that my car's arrangement is, at least, half right. That's a good thing.

This may just boil (no pun intended) down to that beauty-is-in-the-eye-of-the-beholder thing. In the beginning, as our Dinos trundled along the line, Guido may have mused that his strumentazione abitacolo was quite lovely; yet, Luigi was sure that his was as it was meant to be!

We may never know.

With any luck, this drivel may put a smile on your faces.
Cheerfully,
Coop

 

I always questioned the absolute accuracy of the gauges in my Dino.

If the car seemed hot, all you have to do is just turn on the lights. The temp gauge magically drops 10 degrees C. Problem solved. It's magic!

Mine only ran hot when the freeze plugs were leaking from the head. Replacing them solved that problem.

I even had one dead electric fan for a while and it did not overheat, although it would take longer to cool down from the time the temperature sensor turned the fans on.

Oh, and for half of the life I owned the car it was in Phoenix-- not exactly what I would call a cold weather city.

I had more issues with the alternator burning out from excessive heat than from excessive water temperature. I always suspected that the fans drew too much current so if they stayed on a long time (like excessive stop and go traffic), it seemed like the alternator would go be the first casualty. I took it to Monterey one year and lost the alternator going into the Concourse Italiano. I charged the battery before I left and drove the car only on the battery charge from Monterey all the way to LA so I could fix it.

The Dino is a tougher little car than most people give it credit for. Unless the Dinoplex gives out, it always will get you home.

 

Open the trunk, look to your right, unplug the faulty Dinoplex and plug straight into the coil and points system...it will still get you home.

Jim S.

 

Interesting. I never thought of that. But, I never burned out the dinoplex either. When I sold the car, it had the original factory unit still working.

In 15 years of ownership, I never had the car towed ONCE. However, I was very lucky. I broke the clutch cable pulling out of the shop after some routine service. Losing the clutch cable is definately unrecoverable in a Dino.

 

Be careful about removing the thermostat and running the engine as the stat housing is a 3 port valve arrangement. without the stat the water pump will short cycle through the engine block only. If you get water expelling from the expansion tank safety valve line,the car coolant is getting too hot or the rad cap is screwed!!

with a cold engine the stat is closed and circulates water around the block only, when reaching normal operating temperatures the stat opens and closes off the bypass inlet and allows water to circulate around the rad circuit.

Interesting and novel way jimS on bleeding the cooling system, recent experiences of getting Nerodino's car up and running proved to me that it is a ***** job either way. Given the choice, i modified an old rad cap to accept a 1/2" hose and fed this via a small header tank about 10ft above the cars expansion tank. This creates the necessary amount of pressure (about 5psi) to force the air out. Venting the heater modules by undoing the hose connections first, prevents airlocks in the main radiator coolant hoses to form and cause all sorts of aggro!!

tony

 

I have nursed two Dinos home without a clutch cable. Start the car in neurtal, warm to operating termperature. Then place in 1st gear, start car (with no obstructions in front of you) and the car will start easily. Drive to 2,500 RPM, maintain 2,500 RPM without load or trailing throttle (no load on gear box either accelerating or decelerating). Punch gear lever into neutral (without load on gearbox it will go easily). While coasting, bring revs to 1,500 RPM and enter into 4th gear (or 5th gear). The synchronizers will act as clutch and aid your choice of 4th gear (or 5th gear). This is what double-clutching is all about. Drive slow to anticipate red lights and try to avoid stopping. If you stop at a light, put the car in neutral as you approach, turn the engine off, put in 1st gear, and start again. It works and is easy. No damage.

Tony L - what do you do about bleeding air out of the radiator? I like your approach of modifying a radiator cap with a fitting, and creating a column of water above the expansion tank, but this does not help in letting air out of the radiator bleed screw. You still will get a puddle of spillage when trying to bleed the radiator.

Jim S.

 

hi Jim, i have found that the airlocks tend to form in the heater matrixes and connections to the main hose. Bleeding these first eliminates airlocks in the main hoses. Venting the rad is left untill last thing. Unfortunately you do get a wet foot!!

Cheers

Tony

 

continuing with my usual drivel, i had a two hour drive upstate today, and the dino was bloody perfect! needles where they should be, etc...

but, here's a new neurosis-i've noticed that when i let off the gas, i get quite a bit of, not quite backfiring, but coughing, (for lack of a better word) from the exhaust..is that just the glorious burble of the dino, or the the hacking wheeze of a doddering old italian that needs help?