How can identify if the leak is from the crankshaft seal or gear box without taking it out?

JNEILSON10

MEMBER
2007 FIAT PUNTO
TURBO
MANUAL
96,000 MILES

Mechanic has said that there is a leak either coming from the crankshaft seal or gearbox, but wont know until they pull it out, which is going to cost a lot.

I need it to pass MOT as I need it for work. Any way to know without pulling it all out and can I do a simple fix for now until I have the finances to fix it properly?

1 Reply

ASEMASTER6371

MECHANIC
52,797 POSTS

Good morning,

I would clean the area very carefully of all oil residue. Then I would go to a parts store and get a tube of oil dye. Add it to the oil and run the engine for about 2 hours.

https://www.2carpros.com/articles/engine-is-leaking-oil

If it is the rear main, you will see the dye in the oil leaking on the ground. There is no quick fix for that. It is a big job to replace that seal. The seal will need to be replaced and the rear main bearing will have to be replaced or at least checked. The main reason for the seal leak is from the shaft wobbling from wear.

https://www.2carpros.com/articles/crankshaft-main-seal-replacement-rear

If the oil does not show the dye in it, then it is transmission related and that will have to be removed to access the seal.

https://www.2carpros.com/articles/transmission-replacement-removal-manual

Roy