365 GT 2 + 2 restoration

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Timo
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Post by Timo »

O.K.,
First of all, tester You ordered probably has instructions with it, but I'll try to give You an idea how this procedure works and I'm trying to be as simple as possible. You'll start with by removing all spark plugs, radiator cap and oil filler cap(s), then bring #1 piston to absolute Top Dead Center(at compression cycle, both valves closed), You screw-in (or hold it in place, depending on design of Your tester) the appropriate (outlet) end of the tester to the spark plug hole, then connect air pressure hose to inlet side of the tester ( and from this point on, You MUST BE VERY CAREFUL, since the high air pressure introduced in to the cylinder, through the tester, MAY cause the engine to try to turn, if it's not exactly at T.D.C.). Then You'll adjust the regulator on You tester to read 100 psi.
And at this point You'll observe (and write it down for future reference and comparison to other cylinders) the reading of the percentage gauge on the tester. If it reads, lets say, 75-100 %, it means that everything is probably O.K. and the introduced air is NOT escaping through poorly sealing piston rings, valves or broken head gasket . If the readings are lower, You'll need to observe, usually by listening the sound of escaping air ("hissing" as Tom described it) through the various choices. Sound coming prominently through intake / carburetor or exhaust pipe indicates an possible valve problem, respectively. Sound from crankcase possible piston / ring problems and sound / bubbling through radiator possible head gasket problem. Finally, You'll repeat all this with each cylinder, perhaps following the firing order. Readings in all of them should be similar (75-100 %) with no more than 10 % variance.
Timo
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tyang
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Post by tyang »

Another thing to consider is when doing a leak down test, the rings are at the top of the stroke. My concern is that there is a rusty ridge where some of the rings stuck to the the cylinder walls when it seized. This may be a source of low compression, and may not necessarily show up in a leak down test. The plug fouling may not be from fuel, but from oil getting in the combustion chamber.

I'm looking forward to hearing about your compression numbers.

Tom
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klv
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Post by klv »

Hello all. A slightly left -field question about 365 interiors. How does one remove the 'roll' as the front edge of the dashboard. Our one has developed a split in the covering and we would like to ficx it, but are unsure how to remove it. Any suggestions?

Cheers
Andrew Stevens
Kelly La Velle & Andrew Stevens
mark
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dash roll

Post by mark »

Hi Kelly:

This, I have done. It is necessary to remove the glove box interior to gain access to the back side of the top/front of the dash. From there you can reach up under the dash and you will feel some threaded studs protruding at about 10cm on center. You will need a long reach socket, I believe 10mm, to undo the nuts. As you move toward the ignition switch you will need to get at it from under the driver's side, don't think it matters if it is RHD. I removed the panel covering the area between the console and the footwell to reach some of the fasteners. Prepare for scrapes and bruises, if that is possible.

It should come straight off. Mine naturally did not. The blokes in Maranello or PF, put too much glue between the vinyl and the foam. The glue oozed out to the mating surface of the dash and it adhered itself to the vertical surface nicely. It took a thin sharp knife to gingerly release it.

Cheers

Mark
69 365 gt 2+2, 12659
98 M3, 02 Porsche 996
98 550 Maranello
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klv
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Post by klv »

Thanks for that Mark. I guessed it would be fiddly but I wasn't sure where to start! Sounds like I'll need to grease my arm to fit in there first :)

Cheers
Andrew Stevens
Kelly La Velle & Andrew Stevens
A.D.
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Post by A.D. »

A leakdown test was conducted with the following conditions:

a) all spark plugs were removed at one time
b) radiator cap was left open throughout the test
c) max. pressure obtained was 70 pounds with the comprssor that we had

Results are as follows:


Cylinder 1st Meter 2nd Meter % Drop Hissing Sound From
1 70 66 6% carb
2 70 62 12% carb
3 70 00 100% silencer
4 70 53 25% oil pan
5 70 51 28% carb, oil pan
6 70 52 26% oil pan
7 70 00 100% carb, oil pan
8 70 66 6% carb, oil pan
9 70 00 100% silencer, carb, oil pan
10 70 68 3% oil pan
11 70 54 23% oil pan
12 70 46 35% carb, oil pan

a compression test for each cylinder will also be done shortly and i will post the results seperately

my questions are:

1.was the leakdown test done correctly?

2.you have already explained to me that a hissing sound from the carbs means improper intake valves, fro the silencer means improper exhaust valves, but what does a hissing sound from the oil pan mean?

3.what does 100% leakage mean?that when i do the compression test i will probably find no compression at all in these cylinders?

4.what should i do next?-my plan was to pull the carbs from the engine and send them to pierce for a rebuild.should i still proceed with that ?or should i attempt an engine rebuild?

5.where will i find all the parts that i would need for a rebuild -like head gaskets, piston rings, probably valves etc?

as you know i am very very far in terms of distance so pulling the engine and sending it to someone in the us for a rebuild would really be a difficult option

its my bday yet looking at these results i am depressed-need help guys!
A.D.
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tyang
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Post by tyang »

Hi A.D.,

Let's see what we can do to help.

my questions are:
1.was the leakdown test done correctly?
Leak down has to be done on each cylinder when it is at the top of its compression stroke. That means the engine has to be turned for each test until both valves are closed and the piston is at the top of the cylinder.
2.you have already explained to me that a hissing sound from the carbs means improper intake valves, fro the silencer means improper exhaust valves, but what does a hissing sound from the oil pan mean?
Hissing from the oil pan or oil fillers usually has something to do with the piston rings. Depending on how much loss of compressed air it can mean worn rings, or broken rings.
3.what does 100% leakage mean?that when i do the compression test i will probably find no compression at all in these cylinders?
I suspect you were not in the right position to take the compression numbers for these cylinders. The exhaust valves my have been open while you were taking these readings...I hope.


A simple compression test where a pressure gauge is screwed into the spark plug holes should be done first. As the engine is turned over, the gauge will show some kind of compression, hopefully somewhere around 100lbs of pressure. As you check each cylinder, you'll find which ones are low, and you can investigate where the pressure is leaking from with the leak down test.
4.what should i do next?-my plan was to pull the carbs from the engine and send them to pierce for a rebuild.should i still proceed with that ?or should i attempt an engine rebuild?
I would hold off on the carb rebuild. Let's get better leak down/compression numbers.
5.where will i find all the parts that i would need for a rebuild -like head gaskets, piston rings, probably valves etc?
These parts are all available from various parts suppliers in the States, and they are all used to shipping all over the world.
as you know i am very very far in terms of distance so pulling the engine and sending it to someone in the us for a rebuild would really be a difficult option
Although it is not impossible to rebuild the engine yourself, you'll need several specialized tools that you will have to make, besides the usual mechanic's tool kit with a good set of measuring tools. There is no real Ferrari V-12 rebuild guide, so much of the knowledge will be common engine building techniques along with information shared here on this site. The risks are making a mistake unknown to you while assembling the engine only to have it show problems after it's back together, or worse, blowing up a irreplaceable engine. There are others on this site that have rebuilt their engines themselves, and can also offer their opinions on whether it can be done.
its my bday yet looking at these results i am depressed-need help guys!
Happy Birthday, and don't be depressed. You OWN a Ferrari. Poor running engine or not, there are people who never get the chance to own one of these cars. You also have the Internet to help you with a problem that 10 years ago would have been impossible. You certainly have a better chance of getting your car in running condition than in the past!

Tom
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Art S.
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Post by Art S. »

A.D.

Happy birthday!! Don't be depressed. I agree with Tom that you most likely did the test incorrectly.

Do the compression test. Then try the leakdown test again, testing each cylinder when it is at TDC of the firing stroke.

I suspect that when you do these test correctly, we will find that the motor can be made to run reasonably well without a rebuild. (You may need to adjust the valves to get good numbers)

By the way, can you send pictures to Tom so that he can post them for all of us to see.

Regards,

Art S.
1965 330 2+2 series 2 7919
Timo
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Post by Timo »

Hi
I'm sorry, as I wasn't clear enough with my procedure description. Just as Tom described, when testing the "leak-down", each cylinder needs to be in it's top dead center position with both valves closed, so after You've tested the # 1 cylinder, You need to turn the engine manually (from the front of the crankshaft or from the flywheel) to the next cylinder (approx. 1/6th of turn), according to firing order, until it is in top dead center and once You tested that one, You turn the engine again to next and so on, until all cylinders have been tested.
One possible (and relatively easy) way to determine that each cylinder is at top dead center (or very close to it ), unless Your engine flywheel has marked indicators of t.d.c for each cylinder, is to use some thin rod or screwdriver through the sparkplug hole to "feel" the movement of the piston when it approaches the top area of the cylinder (but be careful not to jam the rod/screwdriver with the piston and to help prevent that it's good to have two people when perfoming this, one to turn and one to watch/feel the rod/piston movement) and when very close, turning the crank (or flywheel) back-and-forth to "feel" when the piston seems to be in it's highest spot (more accurate method would be the use of dial indicator, but I wouldn't recoommend it to You at this point, as You can probably get close enough with little practice).
Timo
Rudy van Daalen Wetters
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Post by Rudy van Daalen Wetters »

A.D.

Hang in there and do not give up! Persistance will get you anything. I can't believe the leakdown test was accurately done. Try it again correctly and let's get some real numbers. Happy Birthday, by the way.

Rudy van Daalen Wetters
1963 GTE s/n 4001
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tyang
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Post by tyang »

Also remember there are two times the piston is at the top of its stroke, one for compression and one for exhaust. You want the stroke at the top of the compression stroke, otherwise known as Top Dead Center or TDC. I believe the flywheel on your engine has markings for the TDC of each cylinder. I believe 365 engines have the same sight window like the earlier engines. Look down by the firewall on the center of the engine, and you should see an oval cover plate. Under this plate is the flywheel, and markings of the timing of the engine. Could someone with a 365 confirm this for me?

Tom
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Bryan P
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Post by Bryan P »

you are correct, Tom, but it's not marked as "TDC". The marking for TDC for Cyl. #1 on my euro-spec Queen Mother is marked on the flywheel as "PM 1/7"
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Bryan P
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Post by Bryan P »

strike that; the mark says "PM 1"
1968 365 GT 2+2
s/n 11199
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s/n 0556(0446)MD
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tyang
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Post by tyang »

strike that; the mark says "PM 1"
Thanks Bryan,

I knew it didn't say TDC on the flywheel, but there is a mark corrosponding to every cylinder when it gets to TDC. If you follow the firing order, everything should match perfectly.

Tom
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PSk
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Post by PSk »

A.D. wrote:Results are as follows:

Cylinder 1st Meter 2nd Meter % Drop Hissing Sound From
1 70 66 6% carb
2 70 62 12% carb
3 70 00 100% silencer
Exhaust valve open.
4 70 53 25% oil pan
5 70 51 28% carb, oil pan
6 70 52 26% oil pan
7 70 00 100% carb, oil pan
Inlet valve open.
8 70 66 6% carb, oil pan
9 70 00 100% silencer, carb, oil pan
Both valves open, probably at wrong TDC.
10 70 68 3% oil pan
11 70 54 23% oil pan
12 70 46 35% carb, oil pan
If you remove the 3 cylinders that hopefully were tested at the wrong points she's not that bad for an old (ie. not just rebuilt) engine.

Surely thus if the ignition, carbs and exhaust are made perfect she will run well enough. Might oil a plug up occassionally, but a bit of a rev might sort that.

Will be interested to see the retest numbers.

Best
Pete
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