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1966 chevy engine oil leak fix plan

I have a 1966 Chevy II with a 6 cylinder engine in it. The engine has some small oil leaks that I want to correct. It's been over 30 years since I last rebuilt an engine and I don't recall the details of that effort. Of course good ol Dad was there then too. I'm most curious about how to correct the rear seal of the crankshaft. Below I've listed my plans and some questions I already have.

Please advise me on gasket selection, procedure and anything else you think would help.

Planned Gaskets/Seals to be replaced.

  1. Gasket for valve cover.
  2. Gasket for fuel pump.
  3. Gasket for timing chain cover.
  4. Seal in timing chain cover for harmonic balance/crankshaft.
  5. Gasket for oil pan.
  6. Seal at rear of crankshaft.

Questions.

  1. Regarding the Seal, for the harmonic balance, in the timing chain cover, a. should I precoat the seal-harmonic balance mating surface with anything during assembly? b. is a glue/sealant applied to the seal-timing cover mating surface during assembly?

  1. Regarding the Seal at the rear of the crankshaft, a. can this be easily replaced? I'm suspecting that replacing this would require loosening the bearing journals holding the crankshaft in the block and that would be too risky.

Thanks, Charlie

Reply to
Charlie
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First step: obtain and read dervice manual.

Second, follow procedure therein.

Reply to
Bret Ludwig

Yes. Motor oil. If the snout of the harmonic balancer has a groove worn in it, install a speedy sleeve.

Depends on the seal. Some come with a bead of sealer already applied, if not, I'd use #2 Permatex.

Depends on your definition of easy.

If the original/replacement seal is a rope seal, loosening the crank and allowing it to drop can make things easier, the crank won't drop until the transmission is disconnected though. Not a big deal if it's an automatic, bigger deal if it's a manual trans. If a rubber seal, they go in and out pretty easy.

Nothing risky about dropping a crankshaft a few thousandths, man put it together, man can take it apart.

Reply to
aarcuda69062

Thanks for the reply.

The engine will be out of the car and seperated from the transmission and clutch assembly.

If I loosen the main being journals of the crank to make space for replacing the rear seal does that create a large risk of future main bearing problems?

Charlie

aarcuda69062 wrote:

Reply to
Charlie

Since you're already doing the work of pulling the motor and getting it on a stand, and since you're pulling the pan and timing cover anyway to replace gaskets, what better opportunity to put in new rod / main bearings, oil pump, and timing set. Those parts are relatively inexpensive - should go less than $150 - and if you do it, you'll be sure of the bottom end for years to come.

If you decide not to go that route, and just replace the seals and gaskets, the operative word is cleanliness. Before cracking the mains caps, be sure everything is spotlessly clean, to avoid the chance of any particles getting trapped between the crank and bearings.

And ditto on the balancer repair sleeve - on an engine of that vintage, its almost certain that the soft iron snout of the balancer will have a groove in it. The last two I built, a 77 4bolt main 350, and an 85 4.3 v6 both had worn balancers.

Reply to
v8z

Cool thread. :)

Alvin in AZ ('75 F150 360 T-18)

Reply to
alvinj

all of the baords below are free to register and use.

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all gm trucks pre-1973 / forums / engine anddriveline

The stovebolt page... has a great links page, go to the site, go to links, then click on parts, all the parts vendors are listed there.

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- forums / 60-66 trucks area
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- forums / 60-66 trucks message boardsection

-Woogeroo®

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Reply to
Woogeroo®

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