temp related power loss / no warm idle?

[lukek]

My GTE used to drive fine in stop and go traffic, but some gremlins surfaced after the paint job. I am looking for some leads from more experienced fellow mavens.
When I came back from the painters and also on the return trip from the Palo Alto Concours, the gauge went past 200, and after some sitting in stop and go traffic, the car did not feel like idling anymore. It kept dying and it was hard to restart. When it did, it sputtered and seemed to have only half the power (as if some ignition wires were misrouted....ask me how I know that one). There was no steam, or visible signs of overheating. Once it cools down, it is perfectly happy. During all this, I did not have a chance to see if the fan came on. I was mostly trying not get run over.....I will check it tomorrow.....I am wandering if the painter left the thermostat engaged fan disconnected. But...would the elevated temps translate to a power issue? After the first incident, I thought it was bad gas from sitting for 5 months, or just vapor lock, but twice in the row???!
Any theories on temp related power loss and car dying at idle? Should I bark up the Weber tree instead (walking to garage to study my 3 weber books)?
Thanks in advance
Luke

1963 250 GTE

[horner]

Lukek, Yes, check the fan connection and if it is switching on at the required temp (close to 190F on my 330).

Fan operation notwithtanding, it sounds more like fuel starvation. In a very hot engine bay it can include your vapor lock observation, or evaporation (faster than the pump can keep the bowls filled), or maybe the heat is exacerbating an already weak pump(s) condition. Check to make sure your fuel lines are distant enough from heat sources, that is, have they come loose at some fastener point and drifted too close to heat. Jets need cleaning? Get out the Weber books. Hopefully one of our resident gurus has more to offer. LJH

[jsa330]

Luke;

I don't know if I'm adding anything useful to Horner's advice, but my car ran like a junker after I got it back from a month at the body shop early this year. The problem is that the car gets moved around from place to place a lot and the shop guys just crank it up cold, rev the engine, and move it. I suspect your car is a victim of the same in-shop neglect.

I think old Ferraris are sensitive to this kind of maltreatment and get out of tune in rather inexplicable ways. Anyway, it took a trip to the mech. shop, new spark plugs, and an hour's worth of tweaking to get it right again-in other words, an additional hundred bucks on top of whatever unseen damage may have occurred from careless treatment. It upset me very much that my car came back to me like this, especially after having gone to the trouble to type up detailed startup/shutdown instructions and attach them in plain view to the dash.

I would have halfway expected this from a run of the mill body shop but not from a high end sports/exotic specialist who quoted me 15 grand for a new bare metal paint job. I won't name the shop but I hope the owner perchance reads this.

Scott
Dallas, TX

[David Smith]

Way back when I had a GTE that would do exactly the same thing in stop and go traffic and hot weather. I had to always run with the electric fuel pump on and would not have problems then. Maybe you are already doing this. It does sound like a fuel issue though.

[lukek]

interesting....so when it gets hot, just turn on the "click/click" electric fuel pump that I used for starting? I will still try to make sure that the fuel lines are away from heat sources, and make sure the regular pump and fan are working OK, but this could be the hint that gets me home. I did notice that it started more easily when I primed it to get it restarted.

This is probably sacrilege, but has anyone installed an electric fan in front of the radiator, in addition to the themostat/clutch triggerred one in the back? I had that on the Alfa and it worked very well. It will not help my fuel issue, but it is always a good idea to cool things down.

thx
luke

[Art S.]

Luke,

If you read Tom's early posts, he has step by step installation instructions for modern fans. However, this may not be your problem.

I don't remember how long you have owned the car, have you ever driven the car in stop and go traffic on a hot day before? If not, it's a common issue with old Ferraris. My car occasionally needs the added pressure of the aux. fuel pump to avoid or overcome vapor lock. On the other hand, your mechanical fuel pump may be on its way out.

Good Luck,

Art S.

[Chris Coios]

Luke,

Have you checked the thermostat? It could be stuck closed or part closed.

Chris

[Yale]

Yo, read your manual, it says that use of the electric fuel pump is a must in heavy traffic situations, or something like that. At least my manual says this and I found this out when vapour locked in front of the Holland Tunnel. Next thing that happened on a later drive is that the car would loose power on sharp turns and next thing was that I needed a new fuel pump and all of these "hints" were what was leading up to that. Yale

[lukek]

The condition worsened somewhat, I think..... I have been driving around for 2 years. I need to check the thermostat and the fan clutch operation, anyway, but Art and the others are correct. These are old cars, not built for stop and go and they tend to run hot. I will check to see that the mechanical pump is putting out the required pressure and use the electrical pump when things are heated up. Insulating the fuel lines and installing a modern fan should help further.
Thanks for brainstorming on this one folks. What a wonderful resource !

thx
luke

[Jim]

My two cents: A fuel starvation problem, which could come from several sources: (1) poor performing mechanical fuel pump, (2) obstructed fuel lines, (3) obstructed carb jets, (4) debrisi n fuel tank. My bet: faulty mech fuel pump. The car overheating is a red herring, I think (though that separate issue needs attention).
Sincerely,
Jim

[giovanni44]

Hello Luke,
A few suggestions. Check to see if the paint shop left any masking materials
behind. Especially in the grill area.
If the car has not previously run hot, warm the car up to the point on the temperature gauge that would cause the fans to activate. If they do not ,I
would correct this first. This should be your primary point of attention.
As for the loss of power, this is caused by the fuel in the carburettors evaporating. The engine heat rises and evaporates the fuel faster than the
mechanical pump can replace it. To correct this just activate the electric fuel pump. A word of caution though, if the float levels in the carbs are not set correctly or they become stuck thecarb/s will overfill and leak on to your hot engine.
Best wishes,


Giovanni

[tyang]

Hi Luke,

Although the fan design is pretty inefficient, I think I remember when I looked at the clutch mechanism, there is an adjsutment screw to that will engage the fan full time. If your overheating issue diminishs, then I would look to see if the clutch is bad. If the car still overheats, you may need more cooling.

Just a thought

Tom

[John Vardanian]

Luke,

While you are trying different tricks suggested here, you may also consider un-fouling the plugs after getting out of a traffic jam. It is generally done by running the engine in the third at 4000+ RPM for a few miles. It's a trick used in slow and go rallies like the MM.

If it happens too often you may consider smaller plug gaps. Another thing, if you are using resistored plug boots (ala VW), you may also consider converting to non-resistored.

john

[lukek]

I got the fan from Summit Racing, and it does not clear !!!! Did I get the wrong one, Tom? Would the 330 America have more room between the cross brace and the radiator compared to the 250?
I purchase the Flexalite 16 inch, FLX-116, trimline one.

[lukek]

it turns out that I only have 1.5 inches of clearance between the x shaped frame and the front surface of the radiator. I think I might return the fan. Could a 330 America be different, or did I get the wrong fan?

thx
luke