IROCmatt

can someone run me through changing the oil seal that the harmonic balancer goes on on the crank
the engines a 1983 305 so im guessing u dont have to take the oil pan off, well thats what my book sais?

rough

Think you gotta take that pan off, Well lift the engine enough to get the pan off, do you got a chilton or hayes manual ?

IROCmatt

i got a haynes manual it sais 85 on the pan needs to come off so i take it i dont need to do that as its a very early one, hopefully someone knows, dont want to take pan off if i can help it

8t2 z-chev

No need to drop the pan on an '83(74-earlier i think
you do need to drop pan) when going back together,
make sure the 2 holes for the locating pins aren't
bent,that way the seal is centered properly.also make
sure the crank damper is fully seated against the
timing spocket when reasembled-use longer bolts or
threaded rod and nut to draw it onto the crank.

IROCmatt

ideal cheers, so pull off balancer and timing plate cover and go from there

paulo57509

Pull off the accessory belts.

Remove water pump and crankshaft pulley(s).

Remove water pump (might want to drain the cooling system first).

Might have to remove the radiator to have access for the harmonic balancer removal tool.

Remove the timing chain cover. If you need to pry the bottom of the cover to separate it from the pan, you "might" have to lower the pan. The cover will come out without lowering the pan. Just don't distort the cover when prying. Pay attention to the alignment dowers for the cover.

Once the cover is out, pry out the seal. Install a new seal. Don't hammer directly on the seal. If it distorts, get a new one.

Check the condition of the timing chain while you're in there. If there's any slop, consider replacing the chain and sprockets.

Inspect the harmonic balancer where the seal rides. If there's a groove there, get a new balancer.

Replace the cover with new gaskets. To make fitting of the cover to the pan easier (if you didn't lower the pan) it helps to trim the corners of the lower gasket support that holds the little "smiley" cover-to-pan gasket. It allows the cover to slide into place while at the same time clearing the alignment dowels. Easier to see this during a test fit of the cover than to explain. Use some kind of gasket sealer to ensure you don't have to tear it apart again to re-seal.

If you lowered the pan, shoot some silicone sealer in between the block and pan rails after you clean off excess oil, etc. with brake cleaner. Then tighten the pan to the block. The idea is to put enough in there to re-seal what seal was broken when the pan was lowered. Use good judgment. You don't need the silicon inside the engine; just on the sealing surface.

Replace everything else in reverse order.

IROCmatt

great thanks ill have ago later, should be alright

jamon8

iTrader: (3)

if you shave the inside lip of the timing cover where the front oil pan seal sits - you wont have to drop the pan

sorry I dont have pics but you have to take off about an inch or so on each side

naf

iTrader: (7)

You can get a timing cover seal 'kit' that includes a sleeve that fits over the seal surface on the harmonic balancer and a slightly oversized seal. Put one on my 85 last Summer rather than replace the balancer. 10+k miles later, still good.

paulo57509

Good call. I forgot about these repair kits.