Autolite Carb experts ??????????

[DonsBolt]

Yo
Need a little help with my Autolite 4100 I got from Pony Carbs, that replaced my Holly 570. While for the most part I am happy with the Pony Carb, there are a few things I can't get just right.

The two minor issues that I need to figure out are.
1) when you first let the clutch out there is just a slight bog, which the Holly never did.
2) Setting it up the way Pony told me, I can't get it to idle under 1000RPM's

When I first installed the 4100 and set it up with the timing the way it has allways been, I could get it to idle at 800-900 RPM's. However it had the slight bog right off the line. So I called Pony and they told me the bog is not from the carb, and told me to set the timing the way they did in there video.

So I timed it they way they told me which raised the idle about 200-250 rpms, and while the bog off the line has been reduced it is still there. Now if I try to reduce the idle with the set screw on the drivers side, the gas pedel sticks at anything under 1000 RPM's.

When I talked to them yesterday they had me check for vaccum leaks, I found one-where the choke stove pipe would screw into the choke, however I have a electric choke. So I capped off the stove pipe fitting. They also told me to check my PCV Valve, while it appeared to be OK I replaced it anyways. I went to the Ford dealer and made sure I got the correct PCV. Well neither of those attemps did anything to resolve my two issues.

So maybee someone has a idea or two what I can do to resolve these two little issues, as for the most part I like the way the new carb performs.

?:?

 

[michael welch]

Sounds like a vacume leak.If you are running a edelbrock manifold, they told me (Pony Carb) that vacume leaks were for sure. If you are look at were the carb and the manifold come together, the edelbrock is under cut around the bottom of the carb a bunch. What I did was get a 5/8" phenolic spacer from summit,got a piece of steel tubing the size of my pcv hose drilled a hole in the back of my new spacer were it came out between the back barrels to run my pcv and assembled it but lighty grease between all the gasket material worked perfect.Pony carbs build a great unit.

 

[DonsBolt]

Sounds like a vacume leak.If you are running a edelbrock manifold, they told me (Pony Carb) that vacume leaks were for sure.

I have there Boss 302 Spacer with the PCV Tube in the back, that I got from pony, so thats not the problem. I sprayed carb cleaner all around the bace to check for leaks, and it is sealed up good.

But thanks for the reply

 

[broncnaz]

Sounds like pony carbs didnt quite fine tune your carb. Which is almost impossilbe unless they had your engine But they're pretty close. You might try moving the accerator pump rod to the next hole out on the arm to get a little more fuel when the pedal is moved this usually eliminates the bog. Try setting the timing the way it runs best for you. But really you should be setting the timing and carb with a vacuum gauge trying to gain the highest vacuum reading.
I would check the sticking problem you have also it could be one of the butterflys is slightly off.

 

[bronco italiano]

my first thought was accel pump adjustment. use a vacuum gauge to fine adj. the air idle screws to hight vacuum. make sure vac. adv is plugged. good luck BI

 

[DonsBolt]

Thanks for the advice I will look into the accelerator pump linkage

When I made the post I should have mentioned I did set it with a vacuum guage. I had it up to 22 inches of vacuum at one point ay idle, I had to turn the idle air fuel screws in just a little to get it to idle at 1000 RPM's, so now my vacuum guage reads 21.5 inches of vacuum at idle.

I think you may be right on the butterfly, I may have to pull the carb and look at them

 

[TOFIC]

4100 problem

I agree with all of the above and a few I would check.

The base plate that you got could have the binding problem of the butterflys but you tested it right??

Get that binding in the throttle linkage fixed! that will cause you some grief. as the engine torques something that tight will cause erratic behavoiur at the carb. worse comes to worse get the cable setup from Chuck.

TOFIC

 

[DonsBolt]

I agree with all of the above and a few I would check.

The base plate that you got could have the binding problem of the butterflys but you tested it right??

Get that binding in the throttle linkage fixed! that will cause you some grief. as the engine torques something that tight will cause erratic behavoiur at the carb. worse comes to worse get the cable setup from Chuck.

TOFIC

Thanks Old Fart

I will pull the carb when I get home, and check the butterflys and make sure they are not binding inside the carb. I doubt it is the bace place since the butterflys are recessed into the bace of the carb. At idle they should be allmost closed, and inside the recessed part of the bace plate.

The binding is inside the carb, not in my throttle linkage. When I tried to lower the idle to 800 RPM's it also was binding with the throttle linkage disconected.

I will see what Pony tells me (hopefully Today) as I left them a message yesterday.

 

[TOFIC]

GREAT

Keep us posted. It definitely will help others to know these little things that go wrong.

TOFIC

 

[Action]

How do you get info on these carbs? How are they offroad?
Thanks jack

 

[DonsBolt]

GREAT

Keep us posted. It definitely will help others to know these little things that go wrong.

TOFIC

Will keep you updated

I am sure we will get the little bugs worked out, well that is if they ever call me back. I like the way the carb performs, other than the high idle, and the slightest bog right off the line. Other than that it works great, I have to say it runs smoother than the 570 Holly.

Jack here is the link to Pony Carbs, and I have no idea how it works offroad.

http://www.ponycarburetors.com/default.asp

 

[TOFIC]

As to the offroad working
As close to EFI and dam is to swearing they are that good.
TOFIC

 

[michael welch]

Had one on my 72 for 5 years and it was the best for all a round use and it performed flawlessly off-road to. I know on a hunting trip once going up hill at such a angle that that white smoke started pouring out from under the hood, thinking I had a fire I shut it off and got out and slid down the hill grabing the rear bumper to gain my balance (steep hill) working up to the hood finding out that power steering fluid was coming out of the filler neck dripping on the headers,refired instantly drove on. It was a pony carb rebuild also. What is the current price for a rebuild these days?

 

[DonsBolt]

well lets see if they call me today, they had allmost all day thursday, and all day friday to call me back.

I sent them a e-mail today.

If they don't call me back today I might just send the thing back and put the old trusty Holly back on. There isn't that much of a performance improvement to spend all that money for $hity customer service

 

[shifter]

I dont know much about the motorcraft carbs, do the secondary butterflys have an adjustable stop? If you have determined there are no vacuum leaks and the primarys are closing all the way you may want to check if the secondarys are causing fast idle. With holleys and barry grant style carbs this could also cause off-idle stumble.

 

[DonsBolt]

I dont know much about the motorcraft carbs, do the secondary butterflys have an adjustable stop? If you have determined there are no vacuum leaks and the primarys are closing all the way you may want to check if the secondarys are causing fast idle. With holleys and barry grant style carbs this could also cause off-idle stumble.

I talked to Jon at Pony a hour or two ago, and found out it does have a stop for the secondaries. So maybee thats the problem though you have to remove the carb to get to the adjustment.

They keep telling me I must have a vacuum leak, I checked last week and didn't find any around the carb or the spacer. He also told me it may be a bad PCV Valve so I also replaced the pcv last week. Today he told me to pull the vacuum line going to the brake booster and block that off. Well I did that and no change in ilde.

So I know I don not have a vacuum leak.

I just sent them a e-mail, hopefully they and I can resolve the little issue. If not I will put my Holly back on. It has allways worked perfect, never had any idle issues. Sometimes I wonder why I ever took it off??????????????????

It is a shame, as the carb runs great other than a verry slight bogg off the line, and it idling at 1000 rpms

Frustrated ?:? ?:? ?:? ?:? ?:? ?:? ?:? ?:? ?:? ?:? ?:? ?:? ?:? ?:?

 

[TOFIC]

I am going to take another kick at it.
If you are convinced you have no vacuum leaks, check your vacuum advance on the Dizzy. Remember some of the dizzys were set up for that late 70's gas crunch thing and you have to recurve the distributor to work right. I did mine by putting in the light dizzy springs. Found this info on a website when I was doing mine.
TOFIC

 

[DonsBolt]

I am going to take another kick at it.
If you are convinced you have no vacuum leaks, check your vacuum advance on the Dizzy. Remember some of the dizzys were set up for that late 70's gas crunch thing and you have to recurve the distributor to work right. I did mine by putting in the light dizzy springs. Found this info on a website when I was doing mine.
TOFIC

Thanks
Ya I am sure there is no vacuum leak. I tried sprayin a little carb cleaner, to see if that did anything- No change in the idle. So after a minute or two to make sure the first attempt was evaporated, I really flooded the bace of the carb with carb cleaner- still no change in the idle. I also sprayed carb cleaner around the bace of the intake manafold, by the heads, in the front and the back of the intake- still no change in the idle. I also spryed it around the vacuum fitting for my brake booster, and vacuum guage.

I will look into lighter distributor springs, I know one of the previous owners got rid of the emision heads, but not sure if they recurved the distributor. Do you happen to remeber or have any part numbers for the springs????

 

[robmax]

Vacuum Advance

A couple of things to look at for the hesatation. Check and make sure the vacuum advance diaphram is not ruptured, it'll hold a vacuum, and look in the distributor where the vacuum advance arm attaches to the pin on the breaker plate and make sure the pin is not worn and the hole in the advance arm is not elongated.
On the carb binding. It could be the butterfly, as stated in the other Posts, but it could also be a bent shaft that the butterflies are screwed to.

 

[DonsBolt]

A couple of things to look at for the hesatation. Check and make sure the vacuum advance diaphram is not ruptured, it'll hold a vacuum, and look in the distributor where the vacuum advance arm attaches to the pin on the breaker plate and make sure the pin is not worn and the hole in the advance arm is not elongated.
On the carb binding. It could be the butterfly, as stated in the other Posts, but it could also be a bent shaft that the butterflies are screwed to.

Thanks I will check the vacuum advance tomorow

What do I check to see if it is ruptured or not, aslo if the pin, or the arm are worn are they replaceable, or do I need to replace the distributor??

It really isn't a hesitation, it just had a very slight bog when you first let the clutch out in first gear. Well now with the Holley back on the bog is gone, but I was told the Holley are a little bit more forgiving or may hide some minow other problems.