On to the next thing ... exhaust out aircleaner RH flex duct

[oldelky]

'86 305. After messing with an Over heating issue, stuck themostat, broken water outlet bolts, 2 vacuum switches, bad smog pump, new water pump, new hoses, new fan clutch,....... it doesn't over heat anymore. Whoopee....
Now, getting it runnig after the monthandahalf work, when I started the engine with the aircleaner off, I'm getting exhaust out of the flex duct off the RH manifold to the snorkel !! The flex duct is now positioned to face the fender, and it's deffinately exhaust coming out the duct, and sounds like it too. What the heck is going on here, it's like this old Elky wants to be parked on the RR Tracks ! Is it likely the RH manifold is cracked? Haven't attempted to get under and look while running yet, but is that a common problem? It certainly runs better now than it did before with the parts and repairs to vacuum lines,......... and not having that exhaust spewing flex duct feeding into the aircleaner !!!! Geez, PITA !!

 

[clean8485]

Re: On to the next thing ... exhaust out aircleaner RH flex

Sounds like there is probably a crack in the exhaust manifold. You'd have to remove the sheet metal heat stove where the flexible tube that goes to the air cleaner comes from, and inspect the manifold. The only problem with that, is that unless the heat stove is in very good condition, it will probably be unuseable after its removed. They're usually spot welded together, and over time the metal will rust and weaken out, so that taking them off generally means destroying them.

 

[oldelky]

Re: On to the next thing ... exhaust out aircleaner RH flex

Yep,..... That's the deal all right. Stopped at a muffler shop, and they showed me what I could have seen without stopping there. The top of the RH Exh manifold is cracked, running along the lengthwise top about 3 inches. Of course, I'm Lucky that at least it's the easiest one to replace..........

Can anyone offer a comment on what cars would use the same manifold? I assume that not all 305 V-8s have the same configuration. Also, do any of the after market folks like Year 1 make Repop sheet metal Heat Stove parts? I'll need that to pass smog, that is if this car is still alive by then,................

 

[clean8485]

Re: On to the next thing ... exhaust out aircleaner RH flex

As far as I know, there aren't many differences in the exhaust manifolds for the SBC in the '78-'88 A/G body cars. Also, as far as I know, nobody is reproducing the heat stoves just yet. If anyone else knows anything different, they're welcome to chime in. The way I see it, you have several options. You could remove the exhaust manifold, and try to carefully drill out the spot welds on the existing heat stove (provided that the stove is in good enough condition to do it), save the existing stove, and try to reweld it onto a repaired or replacement manifold. You could try to fabricate a new heat stove, but its probably alot of work. You could start looking through the classifieds, to see if someone removed their original exhaust system to install headers, and saved their original parts, and is willing to sell them, or you could start hitting the local wrecking yards, in the hope of finding the parts you need. If you're looking to find manifolds that might flow a bit better, you could try to find manifolds from a late '80s to early '90s F body (Camaro or Firebird) that came from the factory with a 350 engine. The exhaust manifolds on those cars have the same basic shape and size, but have a larger outlet, so they flow a bit better. The problem with doing something like that, is that you should have a larger sized exhaust system, in order to get any benefit from the better flowing manifolds, so its kind of a snowball effect, when all you really need is a good solid non-cracked manifold with a good heat stove on it. The best suggestion I can give you is to hunt around to see if you can find a good manifold with a good heat stove on it, and just replace the cracked one complete. I hope this helps. Sorry for the long-winded post. Good luck.

 

[oldelky]

Re: On to the next thing ... exhaust out aircleaner RH flex

SO,.............. I thought I would post a follow-up for fun, and also ask a few seriuos questions

After thinking this old Elky was getting louder, and finding Exhaust coming out the heat riser flex duct, right into the air cleaner, I could see a BIT of a crack in the RH cast iron exhaust manifold. :shock: Ignored it for a while, pointed that flex duct away from the air cleaner,...... can you imagine the poor engine breathing exhaust?......... it did run alot better! Finally got around to searching for a replacement part, and found one HERE! 😛 Then the fun began. That RH manifold is a real PITA, to put it mild. :x Got it off, and for your enjoyment, here's a few photos, with a few serious questions I hope someone might have answers to.
Can anyone tell me what caused this, and is there something I should do to avoid it happening again ???
Are there any California G-men out there that have been able to pass smog with the heat riser vavle at the RH exhaust outlet gutted to remove the valve inside? Not sure why I'd like to do it, but now is the time if ever.
Also, Now is the time to finally replace the valve Cover gasket on that side. Maybe I can slow down the weeping that always develops. What do you fellows find is the best cover gasket? I have changed the Left side 3 times, and it seems to last a short while, and then lubes up the plug wires !! 🙁
And last question: There were no exhaust gaskets on the manifold, is this normal? Should I put some one, or is that for better heat transfer? Dunno... :?:

 

[Neuron]

Re: On to the next thing ... exhaust out aircleaner RH flex

I am having the same problem with my drivers side valve cover. I tried a new cover and expensive rubber sandwiched steel and it worked on the passenger side only. Tried a high temp. cork gasket and it is better but still seeping. What a sh***y design, no machined surface for the gasket to seal. I am beginning to think maybe the intake is the one seeping even though all of the bolts are tight.Thank God the passenger side gasket fixed the seeping, it took me days to replace the gasket, bad vacuum lines, heater hoses etc etc etc.

SO,.............. I thought I would post a follow-up for fun, and also ask a few seriuos questions

After thinking this old Elky was getting louder, and finding Exhaust coming out the heat riser flex duct, right into the air cleaner, I could see a BIT of a crack in the RH cast iron exhaust manifold. :shock: Ignored it for a while, pointed that flex duct away from the air cleaner,...... can you imagine the poor engine breathing exhaust?......... it did run alot better! Finally got around to searching for a replacement part, and found one HERE! 😛 Then the fun began. That RH manifold is a real PITA, to put it mild. :x Got it off, and for your enjoyment, here's a few photos, with a few serious questions I hope someone might have answers to.
Can anyone tell me what caused this, and is there something I should do to avoid it happening again ???
Are there any California G-men out there that have been able to pass smog with the heat riser vavle at the RH exhaust outlet gutted to remove the valve inside? Not sure why I'd like to do it, but now is the time if ever.
Also, Now is the time to finally replace the valve Cover gasket on that side. Maybe I can slow down the weeping that always develops. What do you fellows find is the best cover gasket? I have changed the Left side 3 times, and it seems to last a short while, and then lubes up the plug wires !! 🙁
And last question: There were no exhaust gaskets on the manifold, is this normal? Should I put some one, or is that for better heat transfer? Dunno... :?:

 

[dirttrackmonte]

Re: On to the next thing ... exhaust out aircleaner RH flex

I read your last thread about the overheating and man I've gotta say you are one devoted owner. I would have a new motor and entirely too much money in it by now (that's what the wife says. In my mind there is no such thing as too much when it comes to a car that you love. Especially an elky) . I know because im in the process of doing that right now. I figured I would throw you a thumbs up for being so faithful to your ride! Its cool to see someone who loves these cars as much as I do. Keep wrenching my friend

 

[liquidh8]

Re: On to the next thing ... exhaust out aircleaner RH flex

For the valve cover, make sure the flange is flat. I use the good felpro cork gaskets, NO SILICON OR RTV. Clean the valve cover good and use weather stripping glue to glue the gasket to the cover. Clean the head off, and buy these ----> http://www.jegs.com/i/Trans+Dapt/96...&cagpspn=pla&gclid=CJuE0sippLwCFStnOgodPF8A1Q.

I always had stock ones similar to this, not chrome. The tighten the gasket down in a cross pattern. Run it for a days or two, and go back under there and check the torque. The factory bolts should have little star lock washers on them. I usually go a step farther and use the arp valve cover studs with locknuts or washers.

For the exhaust manifolds. Most of the factory manifold I have seen did not have a gasket. But, I usually use the stock replacement gaskets, metal on one side, gasket material on the other. As a matter of fact, I use these on headers for GEN 1 Chevys exclusively.