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Jun 26, 2012 | 11:09 PM

indianaironhead

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carb question

newbie here so please bear with me.i have a 1981 xlh 1000 with an s&s super e carburetor. I completely rebuilt the carb and reinstalled. I used the basic setup from the s&s video as a starting point. I choked the carb to start as usual,when it started with the choke on it redlined,so i shut the choke off but was still running at a high erratic idle and then died after about a minute. I then noticed smoke drifting out of the carburetor. Upon further inspection it seems to have fouled the rear plug. So should i pull the carb back off and start over again or is there something else i should check before I do this? Any ideas on what in the carb i should check first,accelator pump maybe?any help is greatly appreciated.

Jun 27, 2012 | 06:21 AM

IronMick

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From: London, ON Canada

I am not familiar with the S&S carbs.

It could be throttle cable adjustment, or the throttle plate not closing for some other reason. With the engine not running look into the carb venturi while you twist the throttle, observing the throttle plate at the back of the carb. It should not be sticky, and should almost completely close - must stay open a small amount to idle.

High/erratic idle is often caused by intake leaks, air leaks thru the head/manifold/carb connections ...

Intake And Exhaust Leaks Tests

You cannot get a good tuneup if there are intake leaks or exhaust leaks.

1. Check for Intake Leaks

With the engine idling spray propane gas or WD-40 around the carb/intake/cylinder head joints. Propane is best because it leaves no mess, and is most easily sucked in thru leaks. WD-40 is said to work well because it has very fine spray droplets. Be careful to not allow any of either to get sucked in thru the A/C as this will invalidate the results.

Any change in engine RPM is a leak which must be fixed.

EDIT: Experience is that this procedure will identify larger intake leaks, but it may miss very small leaks that also must be fixed. And that propane is definetly the better choice.

EDIT: You have to do a lot of spraying to detect a small leak. Propane will be really clean. Anything else like WD-40, carb cleaner, etc will make a huge mess.

2. Check for Exhaust Leaks

Pour about 1/2 ounce of oil into each cylinder thru the spark plug holes. Run the engine at idle. You will get lots of smoke for about 5 minutes.

All smoke should come from the ends of the exhaust pipes/mufflers. Any other is a leak which must be fixed.

Last edited by IronMick; Jun 27, 2012 at 07:57 PM. Reason: sp

Jun 27, 2012 | 05:01 PM

indianaironhead

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thanks mick! I did notice after I read your reply that the butterfly is staying open a bit and the throttle isnt operating smoothly. I think i might not have the accelator pump and throttle springs set correctly. Does anyone know where I can get a clear picture or diagram of how these springs are placed?

Jun 27, 2012 | 06:43 PM

ROTTEN ROB

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From: POZO, CAL.

First off, S&S Super E carbs don't have a choke. Enrichment/fast idle device. Make sure the plunger to this is seated good. On the throttle side, return spring hooks into throttle spool then shaft lock washer then shaft nut. Flip side,nylon washer,pump actuator lever then actuator spring, hooks to actuator lever then pump actuator arm,lock washer,nut. Once you get the hang of S&S carbs, they are easy to work on and tune.......

Jun 27, 2012 | 08:01 PM

IronMick

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From: London, ON Canada

From the S&S web site ...

http://www.sscycle.com/carbquickguide/

From YouTube ...

http://www.youtube.com/watch?v=I_uH72wDTL0

http://www.youtube.com/watch?v=8mDU3MRmm9A

There is lots more. Google S&S Super E

Jun 27, 2012 | 10:28 PM

indianaironhead

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Thanks Rob, I will check the plunger seat tomorrow after work and make sure it is seating good. It is the throttle spring that is giving me trouble but I'll get it. Mick your knowledge is priceless,thank you once again. I'm going to change the intake to carb and intake to cylinder gaskets because I dont know if they have ever been replaced so I figure it cant hurt.

Jun 30, 2012 | 08:14 AM

indianaironhead

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Problem solved. I changed the fuel inlet from the new one back to the old one,for some reason the enrichment plunger would not seat well on the new one. The second issue was in the throttle cable. Many thanks to Mick and Rob!!!!!