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Topic Review (Newest First)
08-31-2007 09:25 AM
hon_jr
Who knew?

Oh-oh... damage? My bad!

How would I find out or detect if I damaged something by running two pcv's? Could that be the cause of the high-revs at idle? I'll straighten out the tubing situation before we run it again...

Oh, and when we started it again for a few minutes yesterday, there was a strange sound from the left-hand side, like fast pulses of air at high pressure across the edge of sheet metal... I wondered if it was an exhaust manifold gasket problem. Better check that out, too... Since I ran it with two PCV's, I might have done in the valve cover gasket on that side?

Fiscus wrote: "If its idling high you might have a vaccum leak somewhere, or you could be on the fast-idle on the carb. " What does that mean, "on the fast-idle"?

I can search for a vacuum leak, but I think I'll fix that PCV valve issue first: it might be resulting in what the carb sees as a vacuum leak, since they are both plumbed in together...

oh, and thanks for the pics, half-ounce!
08-30-2007 11:55 PM
Jmark Like the others have said, you need ONLY ONE PCV valve. If you run two, it will eventually suck a gasket into the innards of the engine somewhere.

There may be more than one filtered fitting on the aircleaner IF the engine originally came with an A.I.R. pump. They drew air from inside the air cleaner housing before going into the pump.

sounds like you are getting there, just please delete one PCV before you do some damage.

Mark
08-30-2007 11:41 PM
HalfOunce The pcv valve should plug into the fat fitting 3/8" at the base of the carb the vent would go in the opposite valve cover so it could suck fresh air through the engine to the pcv valve. without the vent the pcv system will NOT work correctly... the vent can be of various type one being a tube that runs to a little filter that is mounted in the breather..another type would be like one of them chrome filter vents that plugs into the valve cover the one that is opposite side of the pcv valve.... Found a pic of the vent tube
08-30-2007 11:17 PM
fiscus If its idling high you might have a vaccum leak somewhere, or you could be on the fast-idle on the carb. You only need one pcv valve, ditch the second one and put in a breather.
08-30-2007 11:12 PM
hon_jr
lots of funky things

Yeah, there is a lot of funky things about this engine, but it certainly has a grommetted hole in each valve cover! There are two filtered plastic fittings into the air cleaner, as is often used with PCV's, but the diagram for this car doesn't show them, nor does it show anything fitting to the air cleaner.

Ah well, I'll just skip that for a bit, unless you have pics? Next we need to get the oil and filter changed, and then check out why it is revving so high at idle.

Thanks!
08-30-2007 11:03 PM
HalfOunce You should only have 1 pcv valve in the opposite valve cover you should have a vent of some sort. The factory used a tube with a 90 degree bend that went from the right hand valve cover aka pass side to the breather.
08-30-2007 09:59 PM
hon_jr
It's alive!

Okay, we got it started! You shoulda seen the smile on my 14 year old's face when his Elky started up for the first time!

Broke it in for 20 minutes, now we are draining the oil and changing the filter, then going to try to figure out why it is idling real fast...

More this weekend!
Thanks everyone!
08-12-2007 01:22 PM
hon_jr
Distributor gasket, and wiring shield?

Hey, I've got a few questions about things that are baffling me:

The gasket kit came with a fiber ring that is evidently intended to be a gasket for the distributor. I've heard that sometimes they need to be shimmed to mesh correctly with the drive gear and oil pump shaft: how do you tell if it needs one or not? Aren't they supposed to be able to fit without a gasket? I am using an Edelbrock Performer intake: does that affect this issue?

Also, there is a metal tube about 5 or 6 inches long that the starter wires pass through. It is evidently a shield to keep the wires safe from the nearby exhaust pipes. Does anyone know where that mounts, or better yet, have any pics to show where it mounts??

Oh, and what's the best way to prime the fuel pump, carb and lines before starting the engine? The tank is currently bone dry, so we will have to get the fuel clear up front to the carb before we try starting. Any tips on making this easier?

Thanks, everyone!
-Joel R.
08-12-2007 12:33 PM
hon_jr
2 PCV's

As near as I can tell, the rocker covers are stock. They have brackets on them for mounting the wiring harness clips in, and they are pretty specific. I did install them on the wrong sides, but I'll make it work.

There won't be any problems, running two PCV's, will there? It seems like this would only increase the positive features of the PCV system, but is there something else I don't know about, if I have two PCV's?

Also: I thought PCV's were supposed to be run into the air filter housing, instead of through the little vacuum tubes to the carb?? The diagram shows the PCV being hooked up to the vacuum lines.

Anyway, thanks, and I'll post again after we start it (hopefully, Tuesday eve!)
-Joel
08-11-2007 09:21 PM
DHMag
Quote:
Originally Posted by hon_jr
Hey, Good guess! We found the emissions routing tag on the fan shroud, and it is indeed a YCL. Same diagram as the one you posted.

Funny, my son's car has TWO PCV valves, one in each valve cover.... We just plumbed them together into the same vacuum port, and ignored the EFE and its related TVS, since we don't have the smog pump.

The "vac motor" that is mounted on the intake nozzle to the air cleaner housing connects to the heat riser built into the shroud on the right hand exhaust manifold with a flexible metal tube. (As shown on the diagram), but I can't find the EFE. I don't know what it looks like, but there aren't any other components left to hook up to.

Oh! Unless it is that metal valve in between the RH exhaust manifold and the y-pipe! That makes sense: it had some sort of vacuum device attached to it. I took that off and pitched it, since it was mostly frozen and half destroyed.

Well, I think that answers all of our questions: now we're off to finish fishing wires around the engine compartment, so we can try and start the new engine. Thank you SO MUCH for your help, Dale!
ive never seen an SBC with 2 PCVs. perhaps someone added an additional left hand cover on the right side head, or vice versa. the EFE is the metal valve between the manifold and y-pipe. as long as its frozen in the "open" position, itll be ok as it is.

glad to hear ive helped you out, i wish you luck in getting her fired up !

Dale
08-11-2007 06:17 PM
Cape Cod Bob I just read this thread and hope to find out how u made out staring up. keep us posted. oops, sorry.
08-11-2007 05:48 PM
hon_jr
Thanks, Dale

Hey, Good guess! We found the emissions routing tag on the fan shroud, and it is indeed a YCL. Same diagram as the one you posted.

Funny, my son's car has TWO PCV valves, one in each valve cover.... We just plumbed them together into the same vacuum port, and ignored the EFE and its related TVS, since we don't have the smog pump.

The "vac motor" that is mounted on the intake nozzle to the air cleaner housing connects to the heat riser built into the shroud on the right hand exhaust manifold with a flexible metal tube. (As shown on the diagram), but I can't find the EFE. I don't know what it looks like, but there aren't any other components left to hook up to.

Oh! Unless it is that metal valve in between the RH exhaust manifold and the y-pipe! That makes sense: it had some sort of vacuum device attached to it. I took that off and pitched it, since it was mostly frozen and half destroyed.

Well, I think that answers all of our questions: now we're off to finish fishing wires around the engine compartment, so we can try and start the new engine. Thank you SO MUCH for your help, Dale!
08-11-2007 02:13 PM
DHMag
Quote:
Originally Posted by hon_jr
Wow! Okay, questions: what's an EFE, as listed on the diagram? That diagram looks like it might work, but it only shows the lefthand PCV valve. I assume the righthand one just tees in at the same point?

The Air Management Valve: is that for the smog pump? The smog pump and associated plumbing are missing, except for the righthand exhaust manifold still has the AIR tubes in place... I'm wondering what to do about this, too....

Actually, I won't know if that diagram works till I'm out in the heat (103 expected!) tomorrow. But the tubes that I have already identified appear to be the same configuration. What are the differences with the other 6 diagrams? And why so many configurations? Ergh.

Anyway, thanks for the help! And so fast, too! Dude!

EFE = Exhaust Fume Efficiency valve, also known as the heat riser valve on the right hand exhaust manifold. when cold, it keeps the right hand exhaust manifold closed to allow in speedy heating of the choke stove tube for the choke.

all of the vacuum diagrams i have show the PCV on the left hand side. either side doesnt matter, as long as its plumbed the same way as shown.

yes, the Air Management Valve is for the smog pump. its a valve that comes directly off one of the smog pump tubes. if youre missing some of the smog (A.I.R.) plumbing, you can either replace all of it (if emissions in your state require it to be there) or remove all of it and plug the exhaust manifolds with steel pipe plugs. a friend of mine has an 85ish Bonneville with a 305 and all of the smog equipment is capped off. it passed Texas emissions (which is only a visual inspection in my area) although for my car, they failed me for not having an EGR valve in place.

also, the EFE TVS and Purge TVS are Thermal Vacuum Switches, also known as ported vacuum switch. these are color specific as for what temperature they operate. through my own research, ive concluded that the Yellow = EFE, Purple = EGR, and Blue = Distributor.

as for the rest of the diagrams, they all look to be similar in routing, with only component location being different.

if you look at the upper left hand corner of the pic i posted, it says YCL. this is the emissions label identification. if you still have the original fan shroud, thats where the decal would be located. do you, by chance know what the code is for your vehicle ?

as for the diagrams, im getting them straight from my Chiltons manual for 78-87 GM midsize vehicles.

im glad i could be of assistance to you. holler back if you need more help.

Dale
08-10-2007 11:54 PM
hon_jr
6 others???

Wow! Okay, questions: what's an EFE, as listed on the diagram? That diagram looks like it might work, but it only shows the lefthand PCV valve. I assume the righthand one just tees in at the same point?

The Air Management Valve: is that for the smog pump? The smog pump and associated plumbing are missing, except for the righthand exhaust manifold still has the AIR tubes in place... I'm wondering what to do about this, too....

Actually, I won't know if that diagram works till I'm out in the heat (103 expected!) tomorrow. But the tubes that I have already identified appear to be the same configuration. What are the differences with the other 6 diagrams? And why so many configurations? Ergh.

Anyway, thanks for the help! And so fast, too! Dude!
08-10-2007 11:31 PM
DHMag

if this isnt quite right, lemme know, there are 6 other schematics for an 86 305.
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