81 Carb Gurus

[big2bird]

Okay E4ME Gurus. I have found descrepencies in the manual on E4ME settings.

I just went thru mine.
Float, .420"
Idle mix 3 1/3 turns out
M/C sol 3 1/2 turns out
M/C travel 3/32"\
TPS, .46 volts at curb idle, from B to C
Idle bleed screw at 30* dwell

Runs good. Idles a little erratic.;squint:

 

[Sensei]

I'm not looking at the book right now, but I seem to recall that the MC solenoid adjustment was not a set number of turns, but a measurment that required a special uneven u-shaped tool that was inserted into a vent hole yada yada... I'll have to try and look it up later and get back to you. God bless, Sensei

 

[big2bird]

I'm not looking at the book right now, but I seem to recall that the MC solenoid adjustment was not a set number of turns, but a measurment that required a special uneven u-shaped tool that was inserted into a vent hole yada yada... I'll have to try and look it up later and get back to you. God bless, Sensei

I have that tool. Wondered what it was. $10. says I have to pull the air horn back off to use it. Let me know. Thanks.

 

[Sensei]

Boy, it's been a while since I had to get in depth with this stuff and as I look at it, it is making my brain hurt!:L

I used the adjustment proceedures in the Roe book, page 94 and bottom of 95 for the MC solenoid. The notes I made were just that the lean-mixture screw is part #226 and the rich-mixture stop screw is #72. I fabricated the gages. I remember having to read over these a few times as I looked at the pictures until it all made sense.

The spec I have for the idle mixture screws is 3 3/4 turns (from Delco Carb book, carb# 17081218).

I set my choke and float according to Lars' instructions.

Hope this helps, Sensei

 

[Sensei]

P.S. Looks like the uneven u-shaped tool is for setting the air bleed valve.

 

[big2bird]

P.S. Looks like the uneven u-shaped tool is for setting the air bleed valve.

I tried 4 1/2 turns. Threw the dwell off so far, I almost had to take the idle bleed screw out to get 30* dwell. 3 3/4 turns is the 3rd setting I have heard.
I'll look at the Roe book. I am hot, and very discouraged today.ad

 

[GerryLP]

I have that tool. Wondered what it was. $10. says I have to pull the air horn back off to use it. Let me know. Thanks.

Big2bird,

See if these help things up for you. I also have loaded up some of the pages (it is mostly complete for L81's) of the AC-Delco SD-100A manual. There, you'll find procedures and correct settings for the L81. Printout all the pages to make better sense of it.

http://corvetteactioncenter.com/gallery/showphoto.php/photo/2727/cat/500/ppuser/752

View attachment 14239

 

[big2bird]

Thanks Gerry. I'll go digest this. I have all the tools but the M/C gauge. I have the dimensions to make one though. 1.305"x.170"x.220". Wish I could just find a part# for one that was still in production.

 

[big2bird]

I am beginning to think the carb guy pulled the old "switcharoo." My carb is # 17087132. I don't see it on the list.otfl

 

[Yoda]

I am beginning to think the carb guy pulled the old "switcharoo." My carb is # 17087132. I don't see it on the list.otfl

From my "numbers book" 17087132 shows up as for a 1987 & 1988, 350CID (police ~ 1987 & passenger for 1988)

Just to check... does 17081217 show up for 1981 Corvette Manaul? and do17081218 and 17081228 show up for 1981 Automatic :confused in your literature??

Bud

 

[big2bird]

From my "numbers book" 17087132 shows up as for a 1987 & 1988, 350CID (police ~ 1987 & passenger for 1988)

Just to check... does 17081217 show up for 1981 Corvette Manaul? and do17081218 and 17081228 show up for 1981 Automatic :confused in your literature??

Bud

Near as I can tell from the codes:
170+= does not mean much
81=year
2=49 state/non-Kalifornia
1 or 2=Chevy
Odds are Manual, evens are Auto

So I believe you are correct/fine with those #s

I show this one I have as 87 Cadillac with auto. Now, to see if the settings are the same.

 

[Sensei]

The spec I have for the idle mixture screws is 3 3/4 turns (from Delco Carb book, carb# 17081218).
Sensei

This is the number of the carb that should be on your car! I do not have the specs (idle mixture screw setting etc) for the carb you have. It should be in the Delco book, but I only printed the pages for my carb from an online source. Maybe Gerry can find the spec page you need. God bless, Sensei

 

[big2bird]

This is the number of the carb that should be on your car! I do not have the specs (idle mixture screw setting etc) for the carb you have. It should be in the Delco book, but I only printed the pages for my carb from an online source. Maybe Gerry can find the spec page you need. God bless, Sensei

17081518

5=California emmisions.

 

[Sensei]

17081518

5=California emmisions.

I stand corrected! Good luck. I think I'd go give the guy who swapped it a peice of my mind so he thinks twice before trading out a Vette's original carb again.

 

[GerryLP]

I am beginning to think the carb guy pulled the old "switcharoo." My carb is # 17087132. I don't see it on the list.otfl

Looks that way, Big2brid. Like Rare81 and Seinsei have stated, the correct E4ME carb numbers end on 217 or 218, unless you have a California-emissions Vette.

I recommend that you go back and demand for your original carb (or at least a correct-numbered carb) if it is not too late. Those carb shops know that we Corvette owners are peculiar about OEM parts.

 

[big2bird]

Looks that way, Big2brid. Like Rare81 and Seinsei have stated, the correct E4ME carb numbers end on 217 or 218, unless you have a California-emissions Vette.

I recommend that you go back and demand for your original carb (or at least a correct-numbered carb) if it is not too late. Those carb shops know that we Corvette owners are peculiar about OEM parts.

Well Gerry, I have to tetract that statement. The Carb builder called me and gave me an earfull. Says they NEVER switch carbs, period. I have to believe Bubba did it before I bought the car. Seeing as to what all I have encountered, It's not that much of a reach.:L
Now I have to find out what the correct settings are for my 87 Caddy carb. Other than idle, it does run good.

 

[GerryLP]

Bird,

The rich-screw setting equals the float level setting, so instead of removing the top cover of the carb, check the float setting, and if it is at 4/32", then your rich screw setting is correct. If this one checks-out, then it is likely that the lean mixture screw is also set correctly. Page 138 of AC Delco SD-100A, Procedure 8.

After this, use the "U" shape tool through the "D" vent on the air horn, and place light pressure on the float. Adjust the air valve screw to lightly Touch the gage other leg. NOTICE: THE PARTIAL AC-DELCO MANUAL I POSTED HAS DIFFERENT PROCEDURES FOR THE AIR VALVE SCREWS WITHOUT AN IDENTIFYING LETTER ON IT (LIKE MY ORIGINAL CARB, AND A DIFFERENT PROCEDURE FOR AIR VALVE SCREWS THAT INCLUDE AN IDENTIFYING LETTER ON THE AIR VALVE SCREW. Procedure A (page 139) or Procedure B (page 140) of AC Delco SD-100A.

Once this is c/w, check the signal voltage on the TPS is set to the correct 0.56 volts. See page 126 on AC-Delco SD-100A
The Dwell meter adjustments should be done with a engine that has properly warmed-up. To ensure this, let the engine idle until the water temperature is normal.

The idle fuel mixture screws usually work-out pretty accurately. Set them to 3 1/3 turns. See page 136 for removing the factory plugs AND PAge 138 adjusting ilde mixture screws (AC Delco SD-100A)

 

[Bills money pit]

May I chime in, I believe my 81 is as orginal as found. It is an automatic with carb number 17081228. I hope it is correct carb.

 

[big2bird]

May I chime in, I believe my 81 is as orginal as found. It is an automatic with carb number 17081228. I hope it is correct carb.

It is correct for a non-kalifornia car.

 

[GerryLP]

May I chime in, I believe my 81 is as orginal as found. It is an automatic with carb number 17081228. I hope it is correct carb.

17081228 = automatic tranny / Federal Models

17081217 = MANUAL TRANNY / Federal Models

17081218 = Automatic tranny / California Emmissions

These numbers imply either that there were no California-Emmissions equipped with a MANUAL, or the Corvettes with manual transmission were OK with the State Government of California.:confused