Rebuilt 350, has about 30miles on it. After cam break in, has about 5-7 heat/cool down cycles. City driving with a Flat Tappet. I am a bit green to this so I come to the experts here. I did not build the engine nor install. I do not have the means. I was just wondering if weeping is normal for a freshly rebuilt engine as maybe a “settling in” process takes place, or it should it be dry? All other parts appear dry this is the only spot it looks wet. You can see the oil coming down onto the torque converter cover from above right behind the top First pic is wiped down. Then after a drive. Im in AZ it is hot, engine stays cool, maybe pressure is building up in the oil pan? You may need to zoom in on the 3rd pic
It's pretty common for a Chevy motor to leak oil.... how big of a puddle does it leave after driving for a bit, and parking? Might want to make sure the valve cover and oil pan bolts are tight, but, if it's not a big puddle, and it's not a show truck, you'll probably be better off living with it as it is.
I drove for about 30min today and the pics are from when I pulled into the garage. Wiped clean drove it, came home to recheck, the pics are from this. The spot/dribble on the torque converter cover is about all that weeps. I drove Thursday and checked today and that is what weeped over the that time period. Hadnt even hit the ground yet after 2 days. I”ve had three SBC prior to this, so Im no stranger to weeps/leaks. I checked valve covers, dry. Any other spot and it appears dry. The weep Im fairly postive is the oil pan bolt above the tort converter and the bolt that is visible. Im just super nervous driving. Internet has made me extremely edgy that my engine is a Flat Tappet. Im in 500 mile drive in period. I could not afford rollers. I barely could afford this one.. hahahaha.
Fairly certain. I dont see anything that above that it could be other than oil pan bolts. Everything else abovr appears dry to my eye. Distributer, valve covers are all dry as far as I can tell.
rear main seal leaks are pretty common, it's not easy to get one to seal 100% on a 30 or 40 year old motor
Welp, this is freshly rebuilt. Still the aged. The gentleman who built it and has built them for years is “myvintageiron7512” he is on youtube. Check his SBC playlist. In the video for said engine he says “i dont want any leaks” is that even possible on a Small Block?, I doubt it.
I guess Im posting for some piece of mind. To see what others more seasoned in this than me have to say. Has a warranty of 12months. Im just nervous, if an issue arrives, pay to have it removed, fixed, pay to have installed. Where I live you just cant be doing this stuff in the garage. Lol. ..♂️♂️
If you decide to chase it, I wish you luck....you might get it to quit leaking completly, you might not.
Lol, very true. I guess the best approach will be to keep an eye on it. If it gets worse Ill have no other choice. The amount now isnt really that much. Just annoying after spending what I had for the engine/install. Just to have it leak. Im probably the fool thinking a SBC wont leak, no matter old, just rebuilt or what the builder claims...
Thoughts.........Check the valve covers really good. Many times they will weep oil at the lower rear corners and the oil will spread out and run down the back of the block. It will look just as you are showing in your pics. Usually the leak is so slight that you won't be able to tell with much certainty from up top. A good way to check is with a piece of toilet paper. The paper will quickly absorb any oil that may be there allowing you to see it and know for sure. The rough surface on the head where the gasket sits can sometimes be tough to seal completely, especially at the rear bottom corners because oil pools up there and doesn't ever completely drain away.
All of them that I have had dribbled oil out of that damned hole in the torque converter cover. Really pisses me off, too.
How about the fitting for the oil pressure gauge or idiot light right next to the distributor? Also check the rear gasket on the intake manifold.
Pull the torque converter dust cover and look at the engine side of the flex plate. If there is a centrifugal spray pattern of oil on it, it is the rear main oil seal. You can buy dye to put in the oil and use a black light to find the leak.
Well... With a dry sump system you could pull a slight vacuum inside the crankcase, so even if there are any small leaks it will pull air in through them, not let oil out. But that's an expensive upgrade for stopping oil leaks.
Thats my plan today when I get home from work. A Leaky SBC I normally would just go with it, as it is pretty much expected to leak from somewhere. Maybe Im naive thinking a freshly rebuilt one would be anyless leaky than one run for 40 years, and never being re-built...
There's an art, to bonding cork gaskets to just the valve cover, and warm-ups followed by gradual tightening of cover bolts. The source of the leak, req. patient persistance.
If this is a "rebuild" I would not expect to see any leaks. Take it back and have him fix this while it's under warranty, of course his warranty may not include leaks. I don't agree with the comments that all old SBC engines leak even after a rebuild. There are originally installed decades old engines that have normal mileage that are clean as a whistle on the bottom end. Yes, there are others that aren't, but I would not expect a new rebuild to leak. Old blocks and heads do have their nuances, like needing to be decked to level head surfaces for proper mating, but just looking at the pics it looks like you may have pan, valve cover or real main seal leaks. In one of the pics it looks like the oil pan gasket (or sealer material) is being pushed out probably due to over tightening and a not so flat oil pan flange. As already mentioned, I'd wipe everything down, drive it some more and check (re-check) around the rear main seal and of course the back of the intake and valve covers. After you get tired of troubleshooting your leaks, and since you're not able to make any fixes where you live, take it back to the builder. If he can't or won't resolve it you can take it to someone else or get a drip pan and live with it.
Lots of guy put engines together with dry gaskets, then guys like you and me get to wonder why they leak. I couldn't tell you if that's your case, but I wouldn't be surprised.
Here is roughly 24hrs later. Still no drop to the ground. I didnt notice any oil any other place above. Except the oil pan where it is wet. Everything was dry, that isnt to say it may not be there and I missed it. It looks darn near the same , drop on torque converter is slightly bigger but not heavy enough to drop yet. Ill just keep an eye on and will call the engine builder next week. It just irritating. Im not a rich man. I had to skimp, scrape and sell stuff to afford this. Just to have a leaky engine. I usually do everything as far as my ability will take me, or even learn along the way doing it. I just cant do engine engine swaps where I live. So I had to outsource the work for the engine install and buying a rebuilt 350. So it goes I guess. Just frustrating
I learned long ago that if I really don't want an engine to leak, all I have to do is go buy a new car. They sure make them well these days! the old cars and trucks...well, they have some character, and that usually includes leaving their mark somewhere.
Wise words... I’m my own worst enemy in this. Sometimes I think im in the wrong hobby, me liking perfection and all or something like that. Ill have to let go and just accept leaky SBC’s. Im still going to call the builder.
I hate leaks and go out of my way when I build an engine to ensure I don't have any leaks , but it happens and then you live with it ,take it back to the guy you paid your hard earned money to build it and let him check it out. If he is a straight shooter he will help to solve your problem. If he blows you off and tells you that they all leak then you just got bent over.
The seller stated he stands behind what he does... CALL HIM ! I bet leak coming from back of intake.. Looks like he used the good one piece Felpro oil pan set atleast.
SBCs are like Harleys. They don't leak, they mark their spot. I've had some that didn't leak but it's probably not that common. I'd probably just drive it thinking that it will suck more oil down the guides than it will leak. Pete
My SBC leaks although I took lots of precautions with the gaskets, have cast valve covers, etc. I had Dart stamped covers on it, used gorilla snot to hold the gaskets in place. Still at the short ends, the gasket was sucked in and they poured oil out. Someone gave me a chrome front cover as a gift, so I used it. That pisses out a little. A couple of times a year, I warm up the engine, spray on Simple Green, wait 5 minutes and hose it off, all from the bottom of the engine. Looks good for a while.
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