99 5.7 Vortec front main seal leak -- small. How big a deal?

[strad]

At this point it's what I would call seeping. No drips on the ground. I was just wondering if these things ever catastrophically fail and dump all the oil out in a short period of time (is there any pressurized oil nearby that seal) , or if they typically just slowly seep.

Also, if it's something I need to fix soon, has anybody found or constructed a good diy on it? I'm not a mechanical imbecile, but I haven't done a front main seal yet. Done a head gasket on one of my BMWs as well as a couple oil pan gaskets on them (huge pita). Lots of suspension and brake work.

 

[ezdaar]

its a 2 hour fix by yourself with a trans jack.
Its a very easy fix. just alil time consuming..
Hardest part is getting the darn Y pip bolts loose from exhaust manifolds..

It wont just dump all the oil, but it will get so bad it can loose multiple quarts aday..

 

[SunlitComet]

uh no. for the front seal you do not need a tranny jack nor do you need to remove the exhaust pipes. the procedure is below and the part you to make it easiest is the timing chain cover. it should have the shaft seal already installed and should have either needed gasket included. unless you want to bother pulling out the old seal by it self. With the cover you will restore more sealing area.. BTW once you do pull the old cover it can not be reused.



REMOVAL

NOTE: Any time the composite front cover is removed, the cover needs to be replaced upon reassembly. If the cover that was removed is reinstalled, oil leaks may develop.

1. Remove the crankshaft balancer (external).
2. Remove the water pump.
3. Loosen the oil pan, please refer to Engine, Cooling and Exhaust/Engine/Engine Lubrication/Oil Pan, Engine/Service and Repair/ See: Oil Pan\Service and Repair
4. Remove the crankshaft position sensor. Refer to Powertrain Management.
5. Remove the front cover bolts. NOTE: Use care when removing the front cover from the front of the oil pan seal.
6. Remove the front cover.
7. Clean the varnish and sludge build up from the front cover area.

INSTALLATION

1. Install the front cover and bolts. Use care when engaging the front of the oil pan sealing surface and Gasket with the bottom of the front cover. Install RTV to the lower corners of the front cover to aid in sealing.

• • Tighten the front cover bolts to12 Nm (106 inch lbs.).

1. Install the crankshaft position sensor. Refer to Powertrain Management.
2. Install the oil pan, please refer to Engine, Cooling and Exhaust/Engine/Engine Lubrication/Oil Pan, Engine/Service and Repair/ See: Oil Pan\Service and Repair
3. Install the water pump.
4. Install the crankshaft balancer (external). Refer to Engine

 

[ezdaar]

lol,oops. head was on wrong section of motor.

 

[willxfs]

I did all this a while back. When I removed the front cover, part of the oil pan gasket came out too. (semicircle portion in contact with the oil pan) So then I had to replace the oil pan gasket too. It was a pain in the ass for a novice like myself.

 

[strad]

Haha well damn. The next morning after seeing the seepage on the oil pan, wouldn't you know I see two large drips of coolant under that area on the garage floor. Yep, water pump shaft seal crapped out, and coolant was coming out the weep hole. The leak just didn't get substantial until after I looked at it lol.

I got real lucky. My father in law happened to be here (the experienced bodyman/mechanic) and he helped me break loose the fan clutch (my BMW fan clutch holding tool fits on the Tahoe lol -- got real lucky on that one). Somebody in the past thought it'd be cool to locktite the fan clutch on -- that was fun.

Other than that, the job was easy and straightforward. So I still don't know if the oil seal is leaking, but I now know the water pump was leaking and suddenly started leaking a whole bunch. So maybe that's what the seepage was.

 

[SunlitComet]

is it possible the coolant leak was mixing with grime in front and looking like a oil leak?

 

[strad]

Haha that's what I'm hoping. I'm going to spray some parts cleaner down there and get it clean, then see if I still have a problem.

 

[paulutions]

Haha that's what I'm hoping. I'm going to spray some parts cleaner down there and get it clean, then see if I still have a problem.

Well, over a decade later, are you still alive and can tell us what it was? I am having a similar issue but with whining pulley somewhere (water pump?) and a lot of sudden engine vibration as well so I am thinking that it's a harmonic balancer and front seal, among other things. My theory is that a slight water pump leak and/or the leaking power steering pump degraded the rubber in the harmonic balancer which has since damaged the front seal and, coincidentally, the water pump is finally going out. I have low heat as well and have been chasing through the whole system. I replaced the thermostat, dash switches, checked and flushed the heater core, replaced the rectifier and blend door actuator. Would be hilarious if somehow everything cascaded from a slightly leaking water pump.