Just picked up a cheap 305. I had a whole bunch of parts lying around, and was looking for something to tinker with. The kid who owned it told me one of the lifters had failed. When I went to see it, he demonstrated this by turning it by hand: it made a strange hissing noise.
So I started to pull it apart, figuring I would just replace the entire valvetrain. Got the lifters out, two of them were indeed trashed. But even after I pulled them all out, I could still hear the hissing noise when I turned it by hand.
It sounds like it's coming from the lifter valley, near where the lifters failed. Its LOUD; like there's a very angry cat that crawled into cylinder 1. When I turn it over the hissing continues for a few seconds after I stop. Towards the end, it gurgles a little, like the pressurized air is encountering a little bit of fluid.
Does anyone know what this could be? Could it be blowdown caused by lifter failure?
I appreciate the help in advance.

 

Update:
So I pulled the spark plugs one at a time. The noise is coming from cylinder 7, and only exists when it has a spark plug in it. Interestingly, this is not the same cylinder that experienced lifter failure.

 

Of course it only happens when there's a spark plug: there's no pressure in the cyl otherwise.

If it hisses out the intake port or exhaust port, then it is that valve, leaking.

If it's not coming out the ports, then it's something to do with pistons or rings.

If it was 2 adjacent cyls, it would be a head gasket; blown at the narrow place between cyls.

Not sure how "cheap" a 305 would have to be to be considered "cheap"... how much did you get paid to haul it off? I'd charge somebody at least $50 to take their 305, more if I had to drive very far or if it was a hassle somehow, like real grungy or in a muddy place or something. If they paid me less than that to haul it, it wouldn't be "cheap" at all.

 

Man, I've seen you rag on t-5's all day. The only reason I was trying to grab a 305, was because it's the only thing wimpy enough that I figured I wouldn't have to worry about breaking it. No need to be cold. I'm not a 305 guy either, but damn.

 

I was just hoping that when you said "cheap", that you got paid enough to haul it off, to make it worth your while, and made up not only for all that work, but for still corrupting your premises with it afterwards. How is that "cold"?

But even as weeeeeenie as a 305 is, the T-5 is even worse... the first 3 or 4 or so I tore up, were with a 305. Did nothing but get worse - ALOT worse - when I stepped up the motor program. So, best o' luck to ye, but don't stop saving up for a T-56.

 

Pardon Sofakingdom there, he seems to think you need to have as much as a new car (or a few of them) in a 20+ YO car to have fun with it or learn anything.

Having some hissing when you turn an engine with the spark plug in is normal; this is the air leaking down through the rings on the compression stroke. The gurgling is something that's bad sounding though and may be a cracked head or a puked gasket or similar. Any sign of non-oil fluid in the pan? That's where I'd start. coolant or milkshake is a bad sign. If you can get a starter and a battery hooked up to it, I'd do a leak down or compression test next. The tool's rentable from a parts store if you don't want to buy in.

If you have an air hose, another thing you can do is stick an air line into that spark plug hole (either tap a spark plug threaded section you knock the porcelian out of or go rent a compression checker and remove the check valve temporarily) and you really have 3 options of where it can leak from. Put the cam on the base circle or loosen the rockers so the valves are closed, then see if it leaks out the intake, exhaust or valley. You'll probably know where to go next after that.

If you're okay with a 305, my advice is tear it down, keep the good parts right now and keep looking for a better core; I've bought 3-4 over the years and never paid more for $125 for them. That one had cross hatch in the cylinder bores still, and 2 of the others I bought did as well and they were only $50 each or less. Hell, I had one for an MCSS I sold a bunch of stuff off of and came out ahead on. Not the end all be all of engines by any means but they will get a car on the road again which has its own merits. Keep an eye on Craigslist for one IMO.

That's why my Lemans has a 350 Pontiac in it. I could have started an LS/SBC/BBC/455/2JZ swap, but I'm too busy actually driving it to care right now. Yeah it doesn't make 500hp, but it moves under its own power and lets me put as much mileage on my heap as I can find time to. It also is way more pleasant to drive and has a lot more power than when I got it because I was smart about how I did it.

 

No worries about sof', he's just trying to break my ***** a little bit. The 305 was all of $50, so I'm not beat up about it. Let me know if you have an opening in your 305 disposal unit sofa.
I'm gathering the last few parts for the vortec 355 and the t-56 swap, but I'm a 22 year old pizza guy with a shiny new bachelor's degree in social work; both jobs require driving to nasty areas, so this is going in a beater. I need to not care when it gets stolen. Its my first build anyways, I'll smile ear to ear if it even moves.
So the block makes the noise when the plug is in cylinder 5 or 7. I pulled the head, and the gasket looks solid for whatever that's worth, I'm going to see if I can find a way to seal the cylinders without the heads tomorrow so I can tell if the rings even seal. Thinking of using a CD case and some grease. Now we're officially hot-rodding.
I'll get back to you guys tomorrow. I'm probably the first guy to hope their 305 has a blown head gasket, but thus is life.

 

So color me confused. I'm just at a loss here.
The gasket on that head was puked, or at least I think it was, I have only my vortec block to compare it with. There were no obvious signs of a break in it though.
That said, there is definitely some significant cross hatching left in the bores. Like too much for 31 year old engine, or so I would think. There's better cross hatching than there is in the 19 year old vortec block.
The oil was clean, no milkshake, no coolant whatsoever. I suppose the person I bought it from could have recently replaced it though.
Two lifters were a special kind of ruined; one was leaking, and another was worn concave. One rocker has been replaced, which I hadn't noticed before, but not the one above a failed lifter. The intake manifold is so new that it isn't even dirty. However, the Intake gasket was pretty messed up, it looked like someone tried installing a new one, but left parts of the old one on.
Cleaned the heads up nice, planning on having them magnafluxed tomorrow.
Im wondering if the original owner swapped the intake, but messed up the gasket, causing a leak, which lead to lifter failure. He then tried to fix it by replacing the lifter, but replaced the wrong one. When that failed, he gave up on it, and sold it to me. Sound plausable?
Does anyone have any decent pictures of what a good bore looks like? Same deal with the puked gasket. I'm beginning to wonder if I'm overthinking this. I'll try to post some pictures tomorrow.
Thanks guys.

 

Sounds like somebody rebuilt the motor. Measure the bore dia and see. Then the cam lobe wiped out; he took the intake off to see what had gone wrong, saw THAT, and stuck the intake back on in a big hurry and went looking for ... a buyer. (there are other words that come to mind for what he wanted to find but we won't go there)

There's a good possibility that the reason the lifter failed, is because the lifter bore doesn't point correctly at the cam lobe. Very common out-of-tolerance factory machine work problem.

When a cam lobe goes flat it sheds an AWESOME AMAZING ASTOUNDING amount of metal chips into the oil. Like, to the point that it seems like there's about 5 times as much metal by weight in the form of chips, as appears to be missing from the lifter and the cam lobe. Not sure how that works but it seems pretty universal in these situations. Very rarely does the filter manage to keep them out of all the passages. Once they get there, only way to get rid of them is with a rifle brush; the vat doesn't dissolve em. And you GOTTA get rid of em if any future motor built in that block is to survive, because if they're in there (they are) they oly have ONE place to go; which is, right where the oil flow takes em, which is right directly into your next new set of bearings. If you inspect the bearings you'll probably find chips embedded liberally in them and gouges in the crank, and if so, the passages in the block that are supposed to be carrying clean filtered oil to them, are instead carrying oil mixed with shavings. Not usually thought of as a good thing.

I'm going to go out on a limb and guess that the failed lifter lobe is #7 exhaust?

In NO case could messing with intake gaskets, have damaged a lifter. See my signature for a helpful mental technique you can apply to explaining the root cause of observations you have made of a chain of events.

A head gasket is just a ... gasket. When it leaks, there's a .... leak. If it's good, there's no leaks; and if there's no leaks, it's good. Sounds to me like, if there's nothing wrong with the gaskets, then .... there's nothing wrong with the gaskets. No need trying to convince yourself that there is if there's not.

This doesn't sound like it's going to turn out well. (or "cheeeeeep" either) Prolly best at this point to kiss that $50 goodbye and start over.

 

I bought the heads in to get them magnafluxed, and the guy basically asked me why I would even bother. Basically, it would cost more to rebuild the heads than buy new ones, and these ones (416's) aren't worth it. He advised me to stop touching/taking apart things I don't understand (Also good advice), and that If I felt they were worth trying to keep, I should just chuck them back on the engine and run a compression test.
Sofa, you're completely on point, as usual. Guessed the right cylinder too (I legit looked over my shoulder.) I thought it may have been rebuilt too, but that stock exhaust was rusted on there way too solid, and the pistons are stock. Im still going to strip it down and see what I find. The intake is worth more than $50 anyways, so it's not a complete loss. Who knows, might even be fun.
I'm sure I could flip it off to the next "buyer", but Im not going to do that. The buck stops here. Literally.
The bores look like prime candidates for a flex hone, but from the sound of it, it's probably not even worth doing.
I used electrolysis to clean the heads, and it worked really well. If I see signs of life in that block, Im probably just going to use that on everything. I have nothing to lose. It doesn't cost anything but my time. If the rotating assembly isn't chock full o' cam lobe, I might even consider throwing new bearings and rings on it and letting it die a warrior's death; throwing a rod clean through the pan during a heroic last pull. Isn't that how we all want to go?
If it looks unusable, I'll sell off the redeemable parts for $50. Either way, should be interesting.

 

Electrolysis won't clean up metal chips. It's GREAT on lots of other things but not that one.

If you want to try to salvage the block, take it to the machine shop and have the cam bearings and all the oil gallery plugs removed, have them vat it, and pick it back up from them in that state. Then take it to the quarter car wash in mid-morning on a warm sunny day along with your gun cleaning kit and a small wire brush about the size and shape of a toothbrush. The particular size brushes you will need the most are, if memory serves, the .22 rifle and .410 shotgun ones. Stop along the way and pick up acoupla cans of engine degreaser, the kind that's just diesel fuel in a spray can. (store brand works fine) Run the brush, soaked with degreaser, through EVERY passage in the block: 4 small vertical passages from main bearing saddles up through cam bearing journals all the way to the lifter gallery; 3 front-to-rear passages along the cam tunnel, 1 above the cam and 2 alongside through the lifter bores; 1 vertical from rear main bearing register surface up to the OPSU hole; and several short ones around the oil filter area. Use the toothbrush-like one on the grooves around the cam bearings. Brush them out, then blast the hell out of them all. Repeat if it feels good. Let the block sit out in the sun to dry, turning it different ways about every half-hour or so to expose every surface to the warmth and let all the water drain out of everything. Paint it inside and out when dry and use transmission fluid on a towel to clean the rust off of the bores, lifter bores, and bearing surfaces. That'll get rid of the metal chips: nothing else will. At least that way it'll stand a fighting chance of surviving when you reassemble it. Then take it back to the shop and have em install the cam bearings and the plugs. Make sure they put the cam bearing in with the oil holes pointing down and slightly toward the driver's side; at maybe 4:30 - 5:00 viewed from the front; except for the front one, which has 2 holes, have them put that one in at around 3:00 & 6:00.

For a 305, 416 heads are as good as anything. Ignore the OP's advice, he's already pretty well demonstrated he isn't a good source of info. Nod politely, pretend to agree, thank him kindly for his concern, and ignore every word he says.

 

Ultimately the question I've got to ask is what you're looking to do. Just having an engine doesn't do you much good without an idea of what you're going for.