I've got 178K miles on my Silverado and just started an oil leak at the front seal (front seal, crank seal, timing seal... whatever you want to call it). The oil pan and timing cover are not leaking thanks heavens. Can this be easily removed and replaced without having to pull the timing cover and oil pan off?

I've done this before on other cars, but what little I can find about this repair seems to involve a lot more than I would guess. If I pull the balancer I should be able to carefully pull out the seal without disturbing anything else. What am I missing?

Any advice appreciated!!!

Cheers,
TY

 

Hi traderyoda,

Welcome to the Chevy Forums.

Back before the Earth's crust cooled, back when I used to actually work on engines, it seemed like there was a specialty tool specifically designed for replacing the front and rear main oil seals, without dropping the oil pan. Pulling the harmonic balancer may not be needed.

As I recall, you had to partially loosen, but not remove the oil pan. It was a wiry looking thing, very stiff, and people I knew swore by it. I swore a lot removing those damn oil pans, I know that.

 

according to my haynes manual, since i just did my seal because the new cover i installed 2 days ago had a dead seal. you remove belt, pulley, pull balancer off, I simply poked a blade into the inner part of the seal and it popped right out, I had to buy a 1 11/16 3/4 in. socket to drive the new seal in and then once it was on, re-installed the balancer, pulley and oh boy. now the pan gasket leakin, my luck. but, yea. it also says remove water pump, i just crawled under the truck cuz i just did the cam on the motor, i aint takin that pump off, im lazy

 

The problem is - that the new seal is not going to solve the problem.

The harmonic balancer rides on the lip of the seal and as the seal wears - so too does the harmonic balancer.

The cheap solution is to clean everything up and then tear it apart, making sure not to get any dirt inside of the oil pan. Now is also the time to check the wear on the timing chain.

Take the belts off the front of the engine - with the truck in park or neutral and hold the balancer with both hands and rock the balancer clockwise and counterclockwise and if there is lash in the chain - you will feel it.

They make a seal puller which looks like a claw, which you put inside of the seal and pry out - like the claw on a claw hammer.

Once the seal is out - you clean the area where the seal goes and you put a dab of permetex around the seal and then you hammer it in with a block of wood and a hammer.

You will then see a groove wore around the harmonic balancer where the seal rode. At the parts store, you can buy a repair sleeve which will need to be pressed onto the journal on the harmonic balancer before it is reinstalled. You will also want to put a small dab of oil on the lip of the new seal before you press in the balancer.

Do not pound in the balancer - buy a tool that is designed to push the balancer back onto the crank or you could end up with even more problems.

Do not use the Harmonic Balancer bolt to pull the balancer back onto the crank. If it breaks - you will be looking at a even larger repair bill for a new crank or someone to machine the bolt out of the snout of the crank.

I would also check the condition of the water pump while you have everything tore apart. Now is the time to change it if it is weeping.

 

This information has been very helpful. Based upon what you have shared, I am going to go the "sleeve" option.
Question please: Do you need special tool/tools to install the sleeve?
Thanks again for the enlightenment.