73-87chevytrucks.com

73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: jumpkickyergunt on August 01, 2015, 04:44:56 pm

Title: Bad oil leak from front of engine. Front seal?
Post by: jumpkickyergunt on August 01, 2015, 04:44:56 pm
I'm going to throw in some dye to pinpoint it,  but it looks like the front seal. I'm not seeing anything from the pan or valve covers. Any other possibilities? What is involved in changing a front seal?
Title: Re: Bad oil leak from front of engine. Front seal?
Post by: enaberif on August 01, 2015, 05:44:33 pm
Front seal is a big job as you have to pull most of the front end apart to get to it. You'll need things like a harmonic balancer installer and puller and might as well replace things like gaskets and such. Wouldn't be a bad time to look at your timing chain either.
Title: Re: Bad oil leak from front of engine. Front seal?
Post by: jumpkickyergunt on August 01, 2015, 08:27:39 pm
I've read a lot of different things about what actually needs to be removed to get to the seal. When I look at it, it seems like the fan and shroud are in the way, but I'd be able to get at the seal without having to go much further than that.
Title: Re: Bad oil leak from front of engine. Front seal?
Post by: enaberif on August 01, 2015, 08:35:39 pm
I've read a lot of different things about what actually needs to be removed to get to the seal. When I look at it, it seems like the fan and shroud are in the way, but I'd be able to get at the seal without having to go much further than that.

Rad, shroud, and fan will need to come out.
Title: Re: Bad oil leak from front of engine. Front seal?
Post by: jumpkickyergunt on August 01, 2015, 08:41:56 pm
Rad too? dang. Didn't want to do that.
Title: Re: Bad oil leak from front of engine. Front seal?
Post by: bukweet on August 01, 2015, 09:06:39 pm
Before you tear it apart, identify the problem. Timing chain covers are known for dripping at the pan too.
If it is indeed the front seal on the timing chain cover, be sure to get an offset seal to replace it with.
Title: Re: Bad oil leak from front of engine. Front seal?
Post by: bd on August 01, 2015, 10:16:01 pm
You don't have to remove the radiator, but it does make it a lot easier.  It also ensures that you don't accidentally damage the core.  As long as you have an adequate drain pan and funnel, removing the radiator is far less work than replacing the front crank seal.  Having done the job both ways, I'm with enaberif.

You'll need to remove the crank pulley, as well.  If the timing cover is distorted from a prior seal replacement, plan on swapping it out, now.

As earlier suggested, if you're confident the front seal is leaking, check the balancer and timing chain before disassembly to make sure the timing marks haven't slipped and the chain isn't worn excessively.  It will be a lot less effort to disassemble the front just once rather than have to tear it down a second time later.  If reusing the balancer, inspect it for a groove worn into the hub by the old seal.  If needed, wear sleeves are available to extend the service life of a worn, but otherwise usable, balancer.
Title: Re: Bad oil leak from front of engine. Front seal?
Post by: jumpkickyergunt on August 01, 2015, 11:01:34 pm
If I'm taking it all apart and not wanting to do it again for a long time then should I just plan on replacing the chain and harmonic balancer?  Is it wiser to reuse the timing cover if it's still in ok shape or should that be replaced too? In the end,  my top priority is making it nice and long lasting.
Title: Re: Bad oil leak from front of engine. Front seal?
Post by: bd on August 02, 2015, 01:47:01 am
Do you know the history of the engine?  Sound decisions are based on facts and clear purpose.  Replacing the timing cover, if there's nothing wrong with it, is purely arbitrary.  There's no real benefit.  I suggest that you determine the existing condition of the engine and move forward from there based on what you find. 

In the meantime, consider the following questions.  Do you have a restricted budget?  Is the vehicle your daily driver?  How does the engine run in general?  How much oil pressure does it develop?  Does it burn oil?  Have you performed a compression check?  Approximately how many miles have accumulated on the engine?  If the timing chain is worn out, should you also be concerned about the condition of the camshaft and lifters?  Does it misfire or pop back through the intake when you accelerate?  Is there any metal in the oil?  Is fixing the oil leak a simple repair or is there a bigger long-term goal to be considered?  Do you plan on restoring the vehicle or just affect repairs as they arise?  Do you get the idea?  Before you invest significantly in pricey repairs, determine whether there will be an end to it and/or whether a different approach will be more cost effective.
Title: Re: Bad oil leak from front of engine. Front seal?
Post by: jumpkickyergunt on August 02, 2015, 05:17:27 pm
Ok I gotcha. Is that sleeve n seal that comes with the fel pro gasket kit the wear sleeve referred to in your first post? Looks like the kit comes with a front seal too. Also, is removing the water pump a requirement?

http://m.oreillyauto.com/mt/www.oreillyauto.com/site/c/detail/FEL0/TCS45265.oap?year=1979&make=Chevrolet&model=K10%252BPickup%252B4WD&vi=1297111&un_jtt_redirect (http://m.oreillyauto.com/mt/www.oreillyauto.com/site/c/detail/FEL0/TCS45265.oap?year=1979&make=Chevrolet&model=K10%252BPickup%252B4WD&vi=1297111&un_jtt_redirect)
Title: Re: Bad oil leak from front of engine. Front seal?
Post by: enaberif on August 02, 2015, 08:05:14 pm
Ok I gotcha. Is that sleeve n seal that comes with the fel pro gasket kit the wear sleeve referred to in your first post? Looks like the kit comes with a front seal too. Also, is removing the water pump a requirement?

http://m.oreillyauto.com/mt/www.oreillyauto.com/site/c/detail/FEL0/TCS45265.oap?year=1979&make=Chevrolet&model=K10%252BPickup%252B4WD&vi=1297111&un_jtt_redirect (http://m.oreillyauto.com/mt/www.oreillyauto.com/site/c/detail/FEL0/TCS45265.oap?year=1979&make=Chevrolet&model=K10%252BPickup%252B4WD&vi=1297111&un_jtt_redirect)

If all you are doing is the front seal then no. If you are going to do the timing chain then yes.
Title: Re: Bad oil leak from front of engine. Front seal?
Post by: jumpkickyergunt on August 15, 2015, 01:15:09 pm
All sealed up. Not a drop. Love those rtv free fel pro permadry gaskets. The one piece oil pan gasket is well worth the money. Found a double roller when I went in there. Previous owner did not give me the full story. Also, didn't remove the rad.
Title: Re: Bad oil leak from front of engine. Front seal?
Post by: bd on August 15, 2015, 01:31:28 pm
Good job!
Title: Re: Bad oil leak from front of engine. Front seal?
Post by: jumpkickyergunt on August 15, 2015, 02:40:10 pm
Thanks. The help was much appreciated.