Holgura axial

[_gonbau]

Hello, my father tells me to ask for the forum about the "slack" that has the crankshaft. Whether it is normal or not.
From what I understand, all the engines have a small slack?
What we do not know if this will be the problem of loss of oil pressure 20 years ago.
I will record a video as it is visually better appreciated but the slack consists in rotating the fan "alternator" the belt rotates the crankshaft. If we give in the opposite direction the play makes a bit of play and the nut of the crankshaft leaves a few mm.
Before removing the last spark plug I turned the fan, it turned normally until a point that took force. I understand from the compression of the remaining spark plug. To say that it has an oil leak ... I will clean everything and try to detect where it loses that there is today ... can be anywhere.

[Jon B]

Yes, the crankshaft must have some "holgura axial".

The wear limit is 0.30mm for early engines.
It should not be "a few mm", but maybe I don't understand what you're describing.



Jon B.
Vista, CA

[RSTarga]

Do not rotate the engine backwards.
At some point you really need to get professional help on your rebuild or you will end up in trouble.

No girar el motor al revés, dañas los tensores. Con todo corazón necesitas consultar con personas capacitadas, si no, vas acabar gastando mas y con malos resultados.
El juego de cigüeñal se mide con el motor fuera y parcialmente desarmado.

[_gonbau]

RsTarga, I do not think you understand me when I say turnaround. By this I mean what I do is stop and make it turn in the opposite direction. Without getting to turn it I notice the movement that I comment you (Which wanted to know if in your 911 is normal to appreciate it). A video will be better understood if I can get it appreciated.
Jon B. Thank you very much for the technical information you provide. I have been searching the internet for axial slack and crankshaft. I have realized that it is no longer fixing two things in a restoration. As the engine is "touched" are three. Body .... Motor .... crankshaft. Regarding this and if it is not annoying I ask you.
Have you learned the mechanics of life and time or are you a professional? I would like one day I could get into the engine as many of you do, but for that I still think there are a lot of books missing and some good years.

RStarga!! en español puede que me entiendas mejor. Al girar el ventilador en sus sentido todo correcto. Cuando paro de girarlo y hago como si hiciera que lo giro al otro lado. Se forma un movimiento a traves de la correa que conecta con el cigueñal desplazandose unos mm. Algo que no se si apreciara la camara. Gracias por el interes

saldus

[_gonbau]

I put the videos, what do you think about that movement?

[trdking]

Looks like way too much to me

[_gonbau]

Looks like way too much to me

My father also thinks the same thing but I find it interesting to share it. Before lowering the engine we are investigating that could be the cause 20 years ago. And the most shuffled mechanics without seeing the car was break of crankshaft. Could this be and that the pistons move normally? This task is pending for my father who decided to park the car and let the years go by ...

i have a videodel movement of the pistons which have enough carbon. If you are interested, I can upload it.

Salds

[Jon B]

Before lowering the engine we are investigating that could be the cause 20 years ago. And the most shuffled mechanics without seeing the car was break of crankshaft.

It is very unlikely that the crankshaft is broken on a 6-cylinder Porsche.
The most common cause for this wear is depressing the clutch pedal for too much time, especially when waiting at traffic lights. It is bad for the #1 engine bearing and for the crankshaft.

Jon B.
Vista, CA

[Jon B]

Here is a test to see if your crankshaft might be broken.
With the engine off, have someone sit in the car and depress the clutch pedal. Then have another person in back see if he can still move the crankshaft pulley without much effort.

Jon B.
Vista, CA

[_gonbau]

Here is a test to see if your crankshaft might be broken.
With the engine off, have someone sit in the car and depress the clutch pedal. Then have another person in back see if he can still move the crankshaft pulley without much effort.

Jon B.
Vista, CA

The idea of my father is to put 4 or some long march and to push inside the garage. With this you want to see if turning the engine makes the noise it made when I stopped the engine 20 years ago .... I think it can serve the same purpose that you comment.

pd:On bearings and traffic lights. I still have to look at that topic better. See where oil drips to see if this sheds some light ....