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Discussion Starter #1
JRV: I was following a couple

JRV: I was following a couple of threads in FC regarding the RPMs dropping, in the TR, when one pushes in the clutch as one comes to a stop sign.....then the RPMs go down to 400-500 and sometimes the engine dies. While there where many responses, all where concrned with diagnosing the problem. Did anyone ever come up with the answer?

I have done a search, but get over 200 thread responses.

My TR does this on rare occasions......more annoying at this point. Revs will drop to 1000 and no problem, but they can drop to 500, when on occasion the engine dies.

This seems to happen in spurts.......may do it 4-5 times in a row, then will be OK for a week.

What was the conclusion, as to the problem?

Thanks
 
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Discussion Starter #2
Henry,

when CIS FI engines


Henry,

when CIS FI engines fall below 1000 after hitting the trottle and letting off it's a dead giveaway one or both banks is running rich. The surge will cease by setting mixture back to 0.8% - 1.0% and balancing air flow on both banks. It's probably a good idea to check all the throttle stop settings also to insure both banks are running at the same speed. If one bank is doing all the work at slow speed the sudden drop to idle can be more shock load than one bank can handle alone.

Above is the most direct answer, occasionally the mixture is too rich for something other than the static mixture screw. In those cases the reason for rich running will need to be determined.
 
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Discussion Starter #3
Well JRV, it seems that it is

Well JRV, it seems that it is time to start on the TR.......already have the exhaust gas readings, which you concluded where too high....hence, too rich. You know?......You are REALLY good!!!!!!!

When I go to the parts store for a vacuum gauge, they are ALL from China......I refuse to buy these. Can you recommend a brand name, and source for a GOOD vacuum gauge (need two)......I do prefer the best.

Another question: I posted with FC a question to the Boxer owners about needing a radiator pressure cap. I tested it with my tester.....a Snap-On unit that is 15 years old.......am getting inconsistant readings. Can you recommend the BEST unit I can get to test the Ferraris. I just added 1/2 gallon of coolant mix to the Boxer, to get it to proper level........added 1/2 gallon last year also. Just changed the oil, and no water in the oil.......car runs great......smooth as silk at idle. There are NO leaks in the driveway, nor any noted by looking beneath the car, on my lift. My thought is that the pressure gets too high and the coolant is lost through the overfill tube running down the side of the expansion tank......seems to get down 1/2 gallon, and then stop. The car does not overheat, but does get up to 90 degrees C. rather quickly. One post stated that, while the normal pressure is 1.1, it "balloned" the expansion tank of that owner. Now people are going to a .9Bar cap. Your thoughts?


Thanks
 
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Discussion Starter #4
On my 356BB the handbook says

On my 356BB the handbook says it takes a 0.9 cap yet the parts manual states 1.1. I ordered a new one from Ferrari UK and they sent a 1.1, which I fitted around 400 miles ago.

My car has had a new header tank around 3,000 miles ago (but that was 10 years ago also). I have run it with the 1.1 cap for around 300 miles, which includes some very high temps due to the cooling fans running backwards, and there has been no ballooning yet. I actually checked for ballooning yesterday, funnily enough.
 
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Discussion Starter #5
JRV, my Boxer also sometimes d

JRV, my Boxer also sometimes dies when I pull up at junctions, usually when I come to a stop from high revs. Not often, just sometimes. I guess the rich running might be the reason for this also.

If so how do I weaken off the mixture on the carbs, just be adjusting tehslow running?
 
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Discussion Starter #8
I agree the 1.1 bar cap would

I agree the 1.1 bar cap would not present any problems.

Simon,

To properly reset the Carbs on your Boxer you will need a Gunsons Color Tune, from Gunsons in GB and an Air Balance tool like Uni-Syn or the other Vacum Type (I have one, can't recall the brand name).

First air balance is set, then mixture. Go the the Bottom Permanent Tech Archives and use the Daytona Setting Procedures there, as the guidelines are the same on all carbed cars. One of the guys on Lamborghini-Talk just used those procedures succesfully on his Lambo Espada.

HTH's
 
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Discussion Starter #9
Thanks JRV. I'll give it a

Thanks JRV. I'll give it a go - I have the colortune and a Uni-Syn type gauge.
 
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