Engine number deciphering help needed!

[911-lightning]

Hi all!!!

I have a engine with the number 6401025 stamped on the side of the fan house.
There is a star before and after the number. What kind of engine is this? (year, model...)

Sorry for the "noob" question!

[Cairo94507]

I am going to guess that is a '70 914-6 engine, 2.0 is how they came stock.

[911-lightning]

Hmmm..

The car is an 1980 SC but maybe they have changed the engine? But to downgrade from the 3.0L? Strange

[911-lightning]

Did some reading in the " how to rebuild" book.
Says that the 1980 sc engine 930/07 have the code 6400001 and on

Feel free to comment on this if it is wrong!!!

[sabeo.m]

I have an A series 1980 SC with a 930/07 engine and if I can remember without getting a chance to take a peek, my STAMP starts with 64. When i get home tonight I can verify for you...

[911-lightning]

Originally Posted by sabeo.m

I have an A series 1980 SC with a 930/07 engine and if I can remember without getting a chance to take a peek, my STAMP starts with 64. When i get home tonight I can verify for you...

Thank you very much

[Peter Zimmermann]

"6401025"

6 = 6 cyl engine
4 = 911SC (USA)
0 = 1980
1025 = consecutive build number

[Grady Clay]

This is one of these interesting cases where the engine number could be for two very different engines.
Aside from inspecting the physical engine, the ‘numerical difference’ is in the type number.

Number 6401025 can decode as either:
6 = 6-cylinder unit.
4 = Engine type 901/36 (914-6 not for USA)
0 = Model year 1970.
1025 = Sequential number.
I'm reasionably sure this number was assigned.

Or:
6 = Unit type 6-cylinder engine.
4 = Engine type 930/07 (911SC USA).
0 = Model year 1980.
1025 = Consecutive serial number.

Since the engine is in a 1980 911SC, it is most likely the latter.
The physical difference between the two engines is dramatic.

We all thought that there was some fastidious gnome assigning numbers.
In this case (1980), someone at PAG was asleep at the switch.

Best,
Grady

[911-lightning]

Originally Posted by Grady Clay

Since the engine is in a 1980 911SC, it is most likely the latter.
The physical difference between the two engines is dramatic.

We all thought that there was some fastidious gnome assigning numbers.
In this case (1980), someone at PAG was asleep at the switch.

Best,
Grady

Hi!

Thank you for the reply! My engine is equipped with an oxygen sensor.
Could this be a pointer in the direction of this being an 1980 engine?
Did the engine in the previous 70`s have this component?

[Grady Clay]

Originally Posted by 911-lightning

Hi!

Thank you for the reply! My engine is equipped with an oxygen sensor.
Could this be a pointer in the direction of this being an 1980 engine?
Did the engine in the previous 70`s have this component?

911-lightning,

Oh yes, there is little doubt you have a 1980 911SC engine.
You have CIS injection and an aluminum 930 crankcase, a larger diameter distributor cap, a 6-pin Bosch CDI and the oil pressure sender at the right cam oil line - - among many other detail differences.
Not the least of which is 2994 cc vs. 1991 cc.

The 2-liter type 901/36 has Weber carburetors, a magnesium 901 crankcase, the smaller diameter distributor cap, a 3-pin Bosch CDI and the oil pressure switch near the breather (no gauge sender).

You noted that your engine number was on the fan housing support. The type 901/36 914-6 engine number and type number are stamped vertically on the crankcase near the breather, thermostat and oil pressure switch.


By the way…
WELCOME to the Pelican Forum
You will find a lot of help here.
Flattering pictures of your ‘new’ 911 are required.


Re: Shimming the oil pressure relief spring, HELP,,
I hope you have left your oil pressure spring unmolested.

Exactly what is your “low oil pressure” situation?
What is your oil pressure hot & cold at each 1000 rpm (1000 to 6000 rpm)?
Our 911s indicate very low pressure at idle when hot.
‘Normal’ is about 1 bar for every 1000 rpm to a ‘normal’ max of about 4-5 bar.

There are a number of different oil pressure limiting cap, spring and piston configurations.
With a ‘box of parts’, it is easy to get an incorrect configuration.
Leave it as original.

Lets keep this discussion on your oil pressure thread.

Again, welcome.

Best,
Grady

[djpateman]

Originally Posted by 911-lightning

I have a engine with the number 6401025 stamped on the side of the fan house.

The fact that the number is found on the side of the fan housing is a clear indication of the 911 origin as opposed to the 914/6. On the latter, the engine numbers are found near the oil tower at the flywheel end so that they would be more visible when installed in the car. Of equal importance is the type # which defines the specification of the engine. With both serial and type #'s there is no mistaking the engine.

[911-lightning]

Originally Posted by Grady Clay

911-lightning,

By the way…
WELCOME to the Pelican Forum
You will find a lot of help here.
Flattering pictures of your ‘new’ 911 are required.


Re: Shimming the oil pressure relief spring, HELP,,
I hope you have left your oil pressure spring unmolested.

Exactly what is your “low oil pressure” situation?
What is your oil pressure hot & cold at each 1000 rpm (1000 to 6000 rpm)?
Our 911s indicate very low pressure at idle when hot.
‘Normal’ is about 1 bar for every 1000 rpm to a ‘normal’ max of about 4-5 bar.

There are a number of different oil pressure limiting cap, spring and piston configurations.
With a ‘box of parts’, it is easy to get an incorrect configuration.
Leave it as original.

Lets keep this discussion on your oil pressure thread.

Again, welcome.

Best,
Grady

Thank you so much for the warm welcome

I will write an more detailed post on my oil pressure problem on the correct thread

And post a little picture of the sheep in wolfs clothing

[911-lightning]

Originally Posted by Grady Clay

911-lightning,




By the way…
WELCOME to the Pelican Forum
You will find a lot of help here.
Flattering pictures of your ‘new’ 911 are required.



Again, welcome.

Best,
Grady

Here is an small pic of the car