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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: 197 on May 07, 2008, 03:32:06 PM

Title: SBC 305 HEI Distributor?
Post by: 197 on May 07, 2008, 03:32:06 PM
At school were working on a 305 which is on a elcamino. We pulled the manifold, carb, and distributor off but no one marked where the plug wires went or were the distributor was.

Today we got the new manifold and carb in, and the distributor seated all the way down, but the rotor isn't pointed at the #1 cylinder. Do we need to crank the motor over so that the rotor points at the #1? And then just put the wires on? Or is there some special trick I should know.
Title: Re: SBC 305 HEI Distributor?
Post by: Lt.Del on May 07, 2008, 04:19:51 PM
I don't know who is teaching that class, but, if there are no plans to turn the bottom of the engine (crank, pistons) then someone should have known to mark where the rotor points.

You need to rais the distributor now.  Then turn the crank until the #1 piston is at the top.  Then place the distributor in place with rotor pointing to #1 plug wire.  Hopefully it is on the firing stroke, versus exhaust stroke.  The number 1 piston fires on every other rise. This could cause your distributor to be 180 degrees off and try to fire #6 instead of #1 (in other words, firing on #1 exhaust stroke)

If someone can read the valve opeining on the cylinder head w/ valve cover off, you can see if it is the firing stroke or exhaust stroke.  One valve will be open.  There are two valves per cylinder---i am not sure which valve is exhaust vs. intake.

firing order 18436572
Title: Re: SBC 305 HEI Distributor?
Post by: 197 on May 07, 2008, 04:48:43 PM
Can we bump it over with the starter? The rotor is at about 7:30. I think thats the only spot where it would go all the way down.

Once we get it aligned up, is there any spot on the cap where #1 spark plug wire has to go?
Title: Re: SBC 305 HEI Distributor?
Post by: Lt.Del on May 07, 2008, 04:59:55 PM
you can bump it with the starter, yes.  It will go all the way down in many positions, just play with it.  The sprocket gears must mesh with the gears on the cam.  It will go down in many different positions.  Make sure the distributor cap screws fit on the body of distr (the spring clamps -4)---for HEI i believe there is a little notch where the cap will fit on the body of the distr. 

If you have a vacuum advance, ensure that doesn't hit the firewall when adjusting the timing.  Ensure there are plenty of room from the firewall.

On my HEI on my 79, the #1 plug wire on distr cap pretty much points to the #1 cylinder (roughly the 5:00 position if looking down on engine from radiator area) the silver looking vacuum advance is roughly in the 8:00 position
Title: Re: SBC 305 HEI Distributor?
Post by: HAULIN IT on May 07, 2008, 05:15:50 PM
Ok, If your in auto mechanics class there should be some books/computer, ect. to help you guys with this. A few posts ago we discussed this under the TDC one, check it out. The basics are as follows, we won't get into what you should have done, I think you have figured that out by now. Crank the engine (starter is ok to do) while someone holds their finger over (or ball up a piece of paper towel & lightly push it against the plug hole) # 1 cylinder spark plug hole, it will "pop" as the piston comes up on compression, stop cranking NOW, continue to rotate in the same direction (best by hand on the crank bolt now) until you have the line on the balancer lined up on the tab with 8*-10* BFTC. Pull the distributor & find #1 wire, If you didn't move them, your all set. If not, a manual will help. I saw 78-81 305 was different than most others in one picture I looked at (I didn't know that? oh well) It should be in front of the cap behind the left corner of the carb. Start to the Right of the hold-down screw...18436572. Verify this on your cap. Now mark a line on the distributor base directly straight down from the center of #1 post on the cap. This is where the rotor needs to be pointing. You may have to try several times to get it to "drop" in the right place, sometimes you may have to get a long screwdriver to turn the oil pump drive slightly. Any other questions, just ask! Proceed on, Lorne
Title: Re: SBC 305 HEI Distributor?
Post by: 197 on May 07, 2008, 06:28:41 PM
Thanks for the tips. I know what I would of done but I wasn't there when they pulled the manifold and distributor off.

We wont have any time to work on it untill friday but keep the help coming.

Zach
Title: Re: SBC 305 HEI Distributor?
Post by: Fordeatinz71 on May 07, 2008, 06:59:30 PM
wow, i'm really saddened that the shop teacher doesn't know this.  or is this something that he's not really supervising?  anyhow, if you follow HAULIN IT's tips, you'll get 'er dialed in...
Title: Re: SBC 305 HEI Distributor?
Post by: 197 on May 07, 2008, 07:02:21 PM
wow, i'm really saddened that the shop teacher doesn't know this.  or is this something that he's not really supervising?  anyhow, if you follow HAULIN IT's tips, you'll get 'er dialed in...

I dont think that he was watching when they pulled it. Hes helping though. Hes not the best shop teacher but the only one we got. Thats why I asked here.
Title: Re: SBC 305 HEI Distributor?
Post by: Fordeatinz71 on May 07, 2008, 07:05:38 PM
well, i guess it's a good thing that at least you still have an auto shop class...ya'll will get it handled.  just put your finger in hole #1 and as its turned over (slowly...) you'll feel it push your hand out when you are on the power stroke...then just put something like a straightened coat hanger or a long, skinny screwdriver down the hole on top of the piston and turn until it's all the way at the top...then drop the distributor in with the rotor aimed at 1...then you should be golden...
Title: Re: SBC 305 HEI Distributor?
Post by: camdenoilchange on May 07, 2008, 10:15:56 PM
wow, if your shop teacher can't set a distributor your in trouble. did he get tired of teaching PE and switched to automotive? anyways, good tips listed above. good luck to you!
Title: Re: SBC 305 HEI Distributor?
Post by: 197 on May 08, 2008, 07:10:37 AM
hes more of a lazy "Mopar" man. lol

The tips are awsome. but when we get the rotor to point to the #1 cyl then where to we start putting the wires on?
Title: Re: SBC 305 HEI Distributor?
Post by: Lt.Del on May 08, 2008, 08:40:57 AM
starting at #1, go ahead place the rest of the wires on the cap, clockwise, firing order 18436572

surely he can tell you what cylinder is what....right side (looking from radiator side at engine) is odd, 1,3,5,7 - left is even 2,4,6,8
Title: Re: SBC 305 HEI Distributor?
Post by: HAULIN IT on May 08, 2008, 08:43:23 AM
This should make it a little clearer I hope. 78-81 305
(http://i163.photobucket.com/albums/t285/HAULINIT/firingorder.jpg)
Title: Re: SBC 305 HEI Distributor?
Post by: 197 on May 08, 2008, 02:32:13 PM
Thanks for the diagram!
Title: Re: SBC 305 HEI Distributor?
Post by: Fordeatinz71 on May 08, 2008, 06:10:58 PM
hes more of a lazy "Mopar" man. lol

The tips are awsome. but when we get the rotor to point to the #1 cyl then where to we start putting the wires on?

ahh, Mostly Obsolete Parts Assembled by Retards...lol...Miles Of Parts All over Road...

the diagram is nice, but you can start your number 1 anywhere.  you don't have to have it at a certain place.  that was just where the factory put it.  it will start firing #1 and so forth whereever you wanna start it...
Title: Re: SBC 305 HEI Distributor?
Post by: ccz145a on May 08, 2008, 06:57:38 PM
Quote
the diagram is nice, but you can start your number 1 anywhere.  you don't have to have it at a certain place.  that was just where the factory put it.  it will start firing #1 and so forth whereever you wanna start it...

Now, don't muddy the waters ;) ... the tips so far are advising he find #1 TDC then point the rotor towards the #1 cylinder and the diagram is just to help visualize the point. Once he gets running we can tell how he could have done it.
Title: Re: SBC 305 HEI Distributor?
Post by: Fordeatinz71 on May 08, 2008, 09:08:27 PM
you're right, i'm sorry bout that 197!  just do it by the diagram man!
Title: Re: SBC 305 HEI Distributor?
Post by: 197 on May 09, 2008, 03:39:32 PM
Got it fired up today. Theres no timing notches on this 305 so the owner is going to pick up one of those timing bracket things. We got to figure out all the vacuum lines on the carb I believe that there is three. I think its a Holley 4160 But it has a manual choke.

If anyone can pull a diagram for this carb I would really appreciate it. I got 1 pic of the carb off my phone but I cant get anymore until monday.

(http://img227.imageshack.us/img227/2541/0509081331yb2.jpg) (http://imageshack.us)
(http://img227.imageshack.us/img227/2541/0509081331yb2.b411f6cc31.jpg) (http://g.imageshack.us/g.php?h=227&i=0509081331yb2.jpg)
Title: Re: SBC 305 HEI Distributor?
Post by: HAULIN IT on May 09, 2008, 04:14:52 PM
No that is not a 4160, I'm not sure of numbers, but I believe it is a  "Street Avenger" carb. I'm not very familiar with them. What "diagram" are you hoping to get? Glad to hear you got it running! Lorne
Title: Re: SBC 305 HEI Distributor?
Post by: ccz145a on May 09, 2008, 04:21:44 PM
Nope not a Street Avenger. What is stamped on the air horn?

Found this little blurb on another forum...
http://www.hotrodder.com/cgi-bin/forum/YaBB.cgi?board=02;action=display;num=1162772856 (http://www.hotrodder.com/cgi-bin/forum/YaBB.cgi?board=02;action=display;num=1162772856)
Quote
Holley made two model carbs that used the top plate like a Carter or an Edelbrock.  It was a newer design that Holley came up with (years ago) to help alliviate the leaking problem (which Holley's are notorious for).  The two models were the 4010 and the 4011.  If I remember right, the 4010 ranged from 600 to 750cfm(somewhere in and around there) and the 4011 ranged from 650 to 800cfm.  The quickest way to determine which one you have is to look at the butterfly valves.  The 4010 had all four butterfly valves the same size.  The 4011 had two small primary valves and two large secondaries, much like a Quadrajet.  The second way of telling is the 4010 pretty much had a straight side on the top plate whereas the 4011 was irregular because the secondaries were so huge.  The secondaries buldged out more on the side than the primaries did.  The third way of telling is the choke-horn.  On the 4010, it was a wide-mouth opening and the opening faced the rear of the carb.  The 4011 had a smaller choke-horn and faced the front of the carb.  Hope this helps.
Title: Re: SBC 305 HEI Distributor?
Post by: 197 on May 09, 2008, 04:28:00 PM
Thats what are "Teacher" told us. What I want to figure out, are the vacuum lines on the carb, there are 3.

We had it running at idle for about 10 minutes. As soon as you would touch the throttle it would die (im thinking thats timing issue) We turned it off for a few minutes to check some leaks and hoses and then it would fire run for a few seconds and then die. (timing also?)
Title: Re: SBC 305 HEI Distributor?
Post by: 197 on May 09, 2008, 04:28:51 PM
Nope not a Street Avenger. What is stamped on the air horn?

I wont be able to find out until Monday. The secondary are bigger then the others though.
Title: Re: SBC 305 HEI Distributor?
Post by: ccz145a on May 09, 2008, 04:37:28 PM
Quote
The secondary are bigger then the others though
In that case, it's a 4011.

Here is a link to a schematic: http://www.holley.com/data/TechService/Technical/4011%20Exploded%20View.pdf (http://www.holley.com/data/TechService/Technical/4011%20Exploded%20View.pdf)

Of course, that still doesn't tell you what you want to know. If there are 3 ports... The big one in the back is for power brake booster, then one of the smaller ports is ported vacuum, and the other small one is unported. Most people hook up the distributor to the ported one, it varies vacuum with throtle. You should be able to hear and feel the unported vacuum at idle. If none of the ports were plugged, then that could cause the engine to not idle right and stumble, especially the big one in the rear.
Title: Re: SBC 305 HEI Distributor?
Post by: 197 on May 09, 2008, 04:49:09 PM
thanks!
Title: Re: SBC 305 HEI Distributor?
Post by: HAULIN IT on May 10, 2008, 03:58:11 PM
Glad you got it figured out. Those carbs never caught on, I seem to remember them having a "catchy name" of some sort, going solve all carb problems! you know how it goes. Just as was mentioned, the vacuum hose routing only matters if you still have all of the correct pieces in place. Plug off the ones you don't need, that's all. Have Fun & I hope you have learned a little, Lorne