Autolite 1101 adjustment

[Johnsondawg]

I have been neglecting my garage duties as of late but I finally got back out to the garage this evening. I still have not found the jet I need to lean it out a bit but I'm heading out to the junkyard again this evening to do some scavenging. One thing I have noticed is that my idle seems to have lowered itself in the past couple weeks. I had set the idle so that it idles at 550-600 RPM when it is in drive but as of late it has been idling much lower (400 or lower). I reset it this evening and it seems Ok again but I'm not sure what changed it in the first place. Any ideas what might have caused this? Also, while I was making the adjustments, I noticed that my valve cover has been leaking. The leak is worst at the rear of the engine. This problem has been present since I put the engine in and I have tightened it multiple times but my efforts have only slowed the leak. Is there a better valve cover choice than the standard cork ones?

 

[bubba22349]

I had set the idle so that it idles at 550-600 RPM when it is in drive but as of late it has been idling much lower (400 or lower). I reset it this evening and it seems Ok again but I'm not sure what changed it in the first place. Any ideas what might have caused this?

As a new engine gets some use (miles) it loosens up (less friction) with this the tune will change and fuel economy can improve too.

Also, while I was making the adjustments, I noticed that my valve cover has been leaking. The leak is worst at the rear of the engine. This problem has been present since I put the engine in and I have tightened it multiple times but my efforts have only slowed the leak. Is there a better valve cover choice than the standard cork ones?

The cork gasket works very well unless they are dried out i.e. very old stock (hard) and or they have been over tightened most common cause of trouble. Was the valve cover flange straight when you installed it? That’s also important along with the proper torque on valve cover bolts is only 3 to 5 Ft Lbs. After they set retorque again a second time. Some people like rubber gasket better which ever you use don’t over tighten it just bends the flange and pushes out the gasket.

 

[Johnsondawg]

Still working on this in my limited free time.

Now that I have been driving this daily for a couple months, I have noticed that it runs a little rougher between about 1000 and 2000 RPM. At idle its as smooth as glass and once I'm above about 2000 RPM it smooths back out again. I don't know if this is related to my ongoing carb tuning or not but it bothers me. I have read countless old posts about rough idling but can't seem to find any info on running rough in a specific RPM range. My daily commute takes me through about 20 traffic signals so I spend a lot of time in the 1000-2000 RPM range. Any ideas of where I should start looking to resolve this?

I'm planning on taking yet another trip to the junkyard this weekend in search of suitable leaner jets for the Autolite. If I come up empty again I guess I'll through in the towel and order some so I can get on with dialing in this Autolite 1101.

 

[CZLN6]

Howdy Back Jeremy:

It seems every time you ask for advice all I do is ask more questions. Sorry. But, is the engine "rough" in this rpm range at a steady speed or under acceleration? or both?

The reasons I ask is because they are slightly above the idle circuit function and just into transition circuitry. Have you lowered the float setting yet? That may help. Have you located a smaller main jet yet? That may help too.

Sorry, not much help here. Keep it coming.

Adios, David

 

[Johnsondawg]

David,

In the 1000-2000 RPM range, it does not matter if I'm accelerating or if I'm maintaining speed it runs a little rougher no matter what. Even if I'm parked pushing on the accelerator it will do it. Its not terrible but its noticeable. So far, I sell have not lowered the float. It's supposed to be a little warmer this weekend so I hope to get at that this weekend. I have been to the junk yard looking for jets a bunch of times without any luck. I'll probably have to order some if I don't come up with something soon.

 

[bubba22349]

Is the throttle shaft on the loose side?

 

[CZLN6]

Howdy all:

Good point Bubba. Jeremy, I think you've already checked for obvious vacuum leaks, but I'd suggest that you recheck the throttle shaft bushing, on both sides, at the rpm where it stumbles. Shaft wear may not be the same at all points on the bushing. It may be tight enough not to leak at an idle or upper rpm ranges, but loose in between.

Also, I seem to recall that you picked up your 1101 as a rebuilt. Do you recall any reference to application? That would help ID. For altitude applications 1101s were jetted in the 62 to 66 range, depending on application. That is two numbers lower then their "Normal" jetting. ie, If a '67 F100 pickup with a 223 six in Chicago came with a 68 main jet, in Denver it would have a 66 jet. Not very exact, but that's FoMoCo.

A source for jets that I discovered surfing around is All State Carburetor, in Islip, NY. I have not had occasion to use them yet, but they have a good selection of jets and the price is right. Unfortunately, the jets only come in pairs, but you may be able to peddle what you don't use on this forum. Their phone # is 631-234-8327. Web site is <allcarbs.com/detail>.

Keep it coming.

Adios, David

 

[Johnsondawg]

I don't think the throttle shaft is loose. This 1101 is actually not rebuilt, I got lucky and found this one which is actually a New Old Stock carb. It was still in the box when I got it. I'll check again for vacuum leaks and get the float reset. I'll also check out that source for jets. Thanks for the help.

Jeremy

 

[Johnsondawg]

David,

Thanks for the tip on the web page for the jets. I ordered a 66 and 68. That's the best price I have seen.

Jeremy

 

[Johnsondawg]

I installed the #66 jet this afternoon and reset the float but I think I may have moved the float the wrong way. It seems a bit harder to start and it stalls easily when I back down the curb in front of the house. Once I'm moving it seems to run just fine with the smaller jet. How much lower than the stock spec can / should I lower the float to deal with the stalling issue?

 

[CZLN6]

Howdy Jeremy:

I's start assessing the main jet size by setting the Float to the rebuild kits specifications as a starting point. Have you determined the best choke setting with the larger jet? You may have to richen the choke setting to match the smaller jet and winter weather.

I'm off to the southland tomorrow AM so will not be able to post or check in until sometime in Feb. So good luck til then. Happy New Year!

Adios, David

 

[Johnsondawg]

Thanks david, I had not adjusted the choke at all since changing the jet. If you catch this before you go, how much do you think can lower the float?

Jeremy

 

[CZLN6]

Howdy Jeremy:

I meant the float setting. I'd set the float to recommended specifications with the new main jet and assess from there. I try desperately to only make one change at a time and then assess and adjust. That's me.

Adios, David

 

[Johnsondawg]

Got it, I misread what you wrote. I'm heading out to the garage to dig out my rebuild kit so I can find the specs on the float setting.

Thanks

 

[Johnsondawg]

Well I got my jets last week. I ordered a 66 and a 68 (I was running a 70). I'm running the 66 jet currently and so far its working out well. I have primarily been doing in town driving but it runs very good so far, I have even noticed that the exhaust soot mark that I get when I warm it up in the morning seems to be greatly reduced. This weekend, I'll run it on the highway and check the plugs.

 

[Route--66--]

HELP!
How do you actually adjust the mixture on the Autolite 1100 ?? .. in cars I had years ago (here in England) there was always a screw or something on the carb that you screwed in to weaken or out to richen the mixture.

Is the 1100 different to that??.. do I have to change the jet or something or is there some way of adjusting??

Please see pic of my plugs - there are 3 in the pic .. I think they were numbers 1,2 and 5.
am not sure if the engine is running really rich as the plugs are black or if I'm getting some oil past the rings .. but I don't notice any oil depletion at all and have never seen any blue smoke out the back at all ... so am confused?!
My mate following me said I put out a small puff of black smoke when I floored it a few months back which also makes me think it's running rich..

Sparkplugs pic: http://www.classiques.org.uk/mustang/plugs125.jpg (pic is 1.6mb so may take a few secons to download full image) plugs are quite new (1200 miles maybe..)

CAN ANYONE HELP ?!?!

MANY thanks in advance!!
From 'no-idea about-Autolite-carbs-Limey' !!

 

[Explorer]

Should start a new thread of your own. Idle mix screw is on pass side at base. Left to right, #1 looks a little warm compared to the rest. It looks like you have a mixture of different brands and possible heat ranges for one thing. Could have other issue's but need to have all one brand and heat range of plugs. #2 seems to be Champion and #3 Motorcraft. Or could be my eyes.

 

[bubba22349]

Your plugs don't look real bad but it shows signs of being rich on those two.


Carb tuning

Yes for most all carbs, the idle mixture screw (slotted, knurled, spring under it) and turning it is (IN=LEANER) and (OUT = RICHER). Before you even try setting the carb always set the points (if you have them still) to proper dwell and timing to spec.’s. Next set the Base Ignition Timing to spec. All those tune up parts i.e. points, cap, rotor, wires etc. need to be in good condition

During a carb rebuild the screw is turned in all the way (GENTLY!!), then back it out about 1.5 - 2 turns. That should run well enough to get it to start. Skip this part on running car that you are just tuning up. The "old timer" method can get you within 10% of what you could do with a gas meter and all that nice stuff. Next get it warmed up good.

Once warm; make sure the choke is fully open. If it’s an auto type and not open, than loosen the screws around the black cover and turn it LEAN until it is. This also means that the warm-up fast-idle setting will now have no effect. Choke adjustment will be put off till last

Find the idle-stop screw; set the idle to as low as it will run reasonably. Then tweak the idle mixture screw for the fastest idle speed. If the idle is now "too fast", back off the idle-stop screw to slow it down, and reset until you get it at the highest idle. (An alternative method is to use a vacuum gauge, and adjust idle mixture for highest vacuum.) As a sanity check, the idle mixture screw should be still around 1.5 - 2 turns. If it's crazy far in or out, there's a problem in the carb will need cleaning and rebuild etc.

Then, turn the mixture screw in (LEAN) a tiny bit until you hear the idle speed drop "a bit", 50 rpm or so. It's about the smallest noticeable speed drop. (Alternatively, until vacuum drops 1 - 2 In Hg). That's called "lean idle drop" or "Lean Best Idle RPM". It's good for emissions and a leaner idle is better than richer here. Than reset the idle RPM to spec in drive with parking brake set for an auto trans. With a stock or near stock motor it ought to be very smooth.

Now you will need to wait for the motor to cool down, set the Choke Thermostat Cover to 1 or 2 LEAN. Open the throttle all the way and let go. The Choke should be Partially or Mostly closed (depending on the Air Temp were you are); the fast idle screw should be resting on the stepped cam high Point. It can be hard to see. You can eyeball its operation by opening and closing the choke with your finger and see it step onto and off the cam. Start the car. Without touching the throttle, adjust the fast-idle screw to the "fast idle spec setting ". Once it warms up, opening the throttle should allow the (now hot) thermostat to pull off the choke (open) and also off the fast idle step. That's it you’re done.

 

[Route--66--]

Thanks loads yet again Bubba!
I have started a new thread as requested - please see here for my reply
http://fordsix.com/forum/viewtopic.php?uid=68604&f=1&t=67173&start=0
Thanks!

Should start a new thread of your own. Idle mix screw is on pass side at base. Left to right, #1 looks a little warm compared to the rest. It looks like you have a mixture of different brands and possible heat ranges for one thing. Could have other issue's but need to have all one brand and heat range of plugs. #2 seems to be Champion and #3 Motorcraft. Or could be my eyes.

Spot on.
I had all champion and didn't know if they were the correct 'heat range' so bought a motorcraft from npd or virginia mustang(can't quite remember..) to see if there was any difference in the way they ran - as in I thought the motorcraft would have to be the correct type .. but seems to run the same as the others ..

Will start new thread
Cheers!