As title says, I would like to know if any one knows any common spots where the LT1 likes to leak because mines been leaking for a while now, and I'm going to have some time off work and I'd like to fix it.

I've been thinking it's the rear main seal. But I'm not sure whether it's dripping out of the hole in the inspection cover...or leaking down from somewhere else. It's also hitting the exhaust pipe on the passenger side right where it bends (I'll have a picture up tomorrow). Dad and I are planning on putting the rear up on jack stands, taking the cover off and running it to see if it is in fact the rear main because it'd suck to pull the whole tranny out, replace the rear main, and not have it be that. My uncle also suggested it may be a gasket where the distributor would be on Gen I 350.

Any thoughts?

 

The intakes like to leak in the rear and also the front passenger side corner. The oil pressure unit on the back right behind the intake can also be a problem sometimes. The front seals like the WP driveshaft seal and crank seals on the front are common too. And yes the rear seal can be a pain.

 

All right. We had the thought of it maybe being the back of the intake and thought of putting some RTV sealant on it, letting it sit overnight and hopefully holding up. I know when I first got the car running the valve cover leaked...but that was because the gasket got cut.

I'll have to check tomorrow to see if it's leaking back there. I'm kinda hoping so because that will be much easier to fix than the rear main. I'd just think unbolting the top bolts on the tranny would be difficult with the engine sitting so far back. But I know having a transmission jack will make it much easier if it is in fact the rear main.

 

Just slapping RTV on a leak won't hold for long. If you have the infamous leak between the intake manifold and the rear of the block, which is often confused as a rear main seal leak, you need to remove the intake manifold, clean out the mating surfaces and apply a bead of black RTV on top of the block where it meets the manifold, let it set a while and then reassemble. Of course, the gaskets between the heads and the manifold will need to be replaced.

 

Agreed, just did mine not too long ago. Yet things are still dirty underneath from that leak and I haven't cleaned it off, so I'm not sure if that was my only leak problem. I'll need to handle that soon.

 

I thought mine rear seal was leaking, but after I crawled under and saw it was coming from up top. So I thought it was the intake. But then after a closer it was the valve cover. It was leaking in 1 very small area and running down, saved my self alot of time and money, cause I was ready to pull an intake...

 

Well I wouldn't need it to hold for to long. Just till winter hits. The plan was to run it in the summer, then park it in the winter and pull the engine and rebuild it from the bottom up.

 

how many miles on the motor? you can change the intake gaskets/seals in a few hours. takes me the better part of a day. lol. just keep adding oil. you wont get the rvt to seal from the outside on the oily backside of the intake.

 

A little over 111, 500 miles. We found out today that it was in fact where the distributor would be normally in the 350. I'm going to order new intake gaskets this week and next weekend we're going to tear the intake off and fix the oil leak.

For the most part it isn't a big deal. I've just been adding oil when it needed it since we got it running in April. But that's been getting just too expensive to keep adding it. But a few days ago I let it sit in the driveway running and when I came out the car was filled with smoke from the oil burning off the exhaust...I was only gone for 5 minutes! Haha. So after that I'm like it's time to get it fixed before something catches fire.

 

Disregard the old distributor hole theory. Dad has misinformation. Ha.

Any ways, took of the intake Friday night and what do you know, their was very little RTV sealant on the back of the block and intake. Sooo...we cleaned her all up, applied new RTV sealant (they honestly do not give you enough) and let it sit overnight. Started her up this morning and she idled around 1500 compared to the normal 750ish range. I'm assuming the throttle cable just needs adjusted because you put it in gear and moves decently on it's own. But took it on a 60 mile trip to and back with no leak whatsever!

Also noticed I have a slightly bent pushrod. Will fix when she's rebuilt. Can only imagine how that happened.