Gen1 SBC, carbed, with a breather on one valvecover only, and an "oil" filler cap on the other.

Both breather, and valve covers are edelbrock. The valve covers are baffled. Car runs on 10W30 mobil1 Full syn. no additives. The engine was rebuilt maybe 4 years ago. Has only been driven less than 1000kms per year (600 miles).

THis is the only V8 ive owned that gives off this many "fumes" out of the breather. (ive owned atleast 4 GM V8s, and my freind has had more fords). Its so bad that it will start burning your eyes on long trips. Im gonna put a PCV valve on it for now, but why is it giving off so much?

With the engine warm, you can see the fumes just pouring out of the breather. The fumes arent coloured, you cant see them unless you shine light towards them. The breather is one of these;
http://performanceparts.com/performa...form_66035.jpg

Any ideas why im getting so many fumes? Feel free to ask about engine components, to driving habits or whatever.... Any help appreciated.

 

Good old fashioned blow-by. You definitely need a PCV valve. Who did your rebuild? You might want to talk to them.

 

Wouldnt blowby cause my oil to dirty real quick? I dont think the rings are fried, but maybe just misaligned? Its supposed to have the moly rings in there. The engine is well built otherwise.

Ive never met the guy who built it. The previous owner had it built for himself, and the car sat around for about 2.5 years cuz he had a son, and priorities changed. Then i bought it.

So im on my own for this one.

 

Not really, it's just exhaust. It depends on what "rebuilt" meant to the guy that did it. I've seen lots of spray can rebuilds and lots of new rings on old pistons in out of shape bores with big ridges. The best thing is to do a leak down test on it if you want to know what's going on. For the kind of mileage you're putting on it, I wouldn't worry about it. Just put a PCV on it.

 

The only thing im unsure about on the build is the machining. But theres no way this is one of "those" builds with the way this engine performs. Purrs like a kitten, and theres no vibration or excessive shaking with how bad the idle is "supposed" to be with this cam, which indicates well balanced internals. I dont think he would have skimped on stuff if he bothered to balance it.... Also, it has 74cc heads, which are usually not the first choice for "performance", so id imagine they were reworked. Just little indications like that, that it was done half decent.

But in any case, thanks for the leak down test idea. I was actually preparing to pull the heads (not looking forward to it though). But leak down would be much simpler

Cheers.

 

If you have a compressor and don't have access to a leak down tester, you can pressurize the cylinders. How much air you hear and from where will tell you a lot. If it runs fine, I wouldn't pull the heads for the blow-by.

I don't believe anything anyone tells me unless they have a receipt or I can see it. I guess I'm either jaded or experienced. Pick one :-)

 

I guess im still young an naive The "build" hasnt let me down yet, so i think im in good hands.

Thanks again for the tips. ill try the compressor thing, but i can probably get my hands on a leak down testor.