Help Needed: LT4 Oil Leak
Thread Starter
Intermediate
Joined: Aug 2007
Posts: 31
Likes: 0
Help Needed: LT4 Oil Leak
As the title says, I am looking for help with an oil leak on my LT4.
The leak started pretty suddenly and is coming from the front of the engine. The leak only happens with the engine running and will pump out an ounce or two within 10 minutes. I initially thought it was the crank position sensor, so I already replaced that. I now see it is coming from some place higher up.
I got the water pump off yesterday and can see that the intake manifold, heads and water pump drive shaft are dry, so I'm guessing front cover.
Anyone have an idea of the probable cause?
I am ready to pull the balancer off to get to the opti spark. The manual mentions raising up the engine. Can I squeeze the balancer off without lifting the engine?
In case I find that it's the oil pan leaking, do I need to lift the engine to remove the pan or can this be dropped with the engine in place?
Thanks in advance for any help.
The leak started pretty suddenly and is coming from the front of the engine. The leak only happens with the engine running and will pump out an ounce or two within 10 minutes. I initially thought it was the crank position sensor, so I already replaced that. I now see it is coming from some place higher up.
I got the water pump off yesterday and can see that the intake manifold, heads and water pump drive shaft are dry, so I'm guessing front cover.
Anyone have an idea of the probable cause?
I am ready to pull the balancer off to get to the opti spark. The manual mentions raising up the engine. Can I squeeze the balancer off without lifting the engine?
In case I find that it's the oil pan leaking, do I need to lift the engine to remove the pan or can this be dropped with the engine in place?
Thanks in advance for any help.
Safety Car
Joined: May 2007
Posts: 3,651
Likes: 10
From: Apple Valley MN
I had no problem getting the balancer off on my LT4, but couldn't pull it all the way out of the car, as it was trapped between the hub and cross-member. I imagine lifting the engine would have provided sufficient clearance to get it out. But it wasn't necessary to do this - had plenty of clearance to work on the opti even with the balancer still captive:
http://bradprestonmusic.com/Photos/V...s/dscn1036.jpg
Good luck with finding your leak! I had a couple leaks on mine, but they turned out to be from the valve cover gaskets and from the ends of the intake manifold. I replaced the VC gaskets and snugged down the intake bolts (which were a bit loose on the ends), and so far, it's dry as a bone.
http://bradprestonmusic.com/Photos/V...s/dscn1036.jpg
Good luck with finding your leak! I had a couple leaks on mine, but they turned out to be from the valve cover gaskets and from the ends of the intake manifold. I replaced the VC gaskets and snugged down the intake bolts (which were a bit loose on the ends), and so far, it's dry as a bone.
Team Owner
Joined: Feb 2006
Posts: 23,165
Likes: 117
From: San Antonio Texas
I had a leak just like that on mine, and just finished an Opti install too. I had to loosen the steering rack and pull it forward a little to clear the damper ring to get it out of there. I think if I had to do it over, loosening a motor mount and lifting it up might have been easier. My leak was the front seal. The hub had a groove worn in it where it rides on the seal and the oil was seeping out and running down over the crank sensor, making me believe that was where it was leaking. I had to pull the hub and install a sleeve on mine. It looks like a small soda can with the top cut off and a hole in the bottom to fit over the end of the hub. It's only a couple of thousandts thick and just presses on the back of the hub. I installed mine with a 2x4 and tapped it on with a hammer. I got it at NAPA, they called it a 'ready sleeve'. I think some are called a hub saver too. I think it was about $7.00
My water pump drive was also seeping oil so I took off the front cover and pulled that drive shaft out, plugged the hole and put on an elecrtic water pump. Drove it for the first time yesterday and haven't seen any leaks. Those are two places (one water & one oil) that won't leak for me any more!
My water pump drive was also seeping oil so I took off the front cover and pulled that drive shaft out, plugged the hole and put on an elecrtic water pump. Drove it for the first time yesterday and haven't seen any leaks. Those are two places (one water & one oil) that won't leak for me any more!
Race Director
Joined: Apr 2000
Posts: 15,344
Likes: 4,009
From: Texas
Probably one of the front cover seals. Pretty typical given the age of the cars.
Lifting the engine takes at least 2 minutes....Loosen (until they're almost all the way off) the two 18mm nuts (one/side) that pass thru the diagonal frame brace. Put a floor jack under the transmission with a block of wood to spread the load. Jack the engine ~1" Pull the damper out.
Lifting the engine takes at least 2 minutes....Loosen (until they're almost all the way off) the two 18mm nuts (one/side) that pass thru the diagonal frame brace. Put a floor jack under the transmission with a block of wood to spread the load. Jack the engine ~1" Pull the damper out.
