Carb cough issues
Tourer
Joined: Feb 2016
Posts: 309
Likes: 39
From: Southlake Texas
It's obvious the 48 is too rich at idle. I would go back to the 46 (or even 44), and look at the accel pump. Of course, if you didn't change the intake seals the first time around, do it this time, since an intake leak throws everything off.
Cruiser
Joined: Jun 2017
Posts: 135
Likes: 12
From: Omaha
This, but more likely a 45. Clean the carb, throw a rebuild kit in, change your gaskets, including the intake, readjust your float height. If you have to have it at more than 3 turns out with a 45 after all that, you have an intake leak.
Thread Starter
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6th Gear
Joined: Mar 2017
Posts: 14
Likes: 0
From: Mid-West
Such great advice!
So I tore the whole carb apart and cleaned everything. Sprayed out the jets and basically every little crevice. Took a small tooth brush and scrubbed the inside. All the parts and rubber looked pretty good. I went ahead and bought a whole rebuild kit with new flanges for the intake manifold and seals. The previous owner put in the Sportster needle so that's all done. I put the 46 jet back in as well. Turned the mix screw out 2 1/4 turns. Also checked the plugs, they were black but I know that 48 idle jet was dumping fuel. Cleaned those up as well.
Went out because I was curious and threw the carb back on. Hooked it all up real quick and she fired up instantly. So the hard start was definitely gone. I let it idle with the choke and followed the factory warm up procedure. There was one cough and it was pretty loud and stalled the bike. Started it back up and sprayed some carb cleaner around the seals and the rpm dropped a bit but not enough to stall out. So as most of you said, it's for sure the intake seals. Ill take everything back off tomorrow and rebuild/reseal it all. All in all I'm going to be out $45. My buddy ended up having a allen manifold tool so that's a plus.
I will do all of that tomorrow then come back and let everyone know how it goes. You guys have been awesome and I really appreciate all the responses.
Went out because I was curious and threw the carb back on. Hooked it all up real quick and she fired up instantly. So the hard start was definitely gone. I let it idle with the choke and followed the factory warm up procedure. There was one cough and it was pretty loud and stalled the bike. Started it back up and sprayed some carb cleaner around the seals and the rpm dropped a bit but not enough to stall out. So as most of you said, it's for sure the intake seals. Ill take everything back off tomorrow and rebuild/reseal it all. All in all I'm going to be out $45. My buddy ended up having a allen manifold tool so that's a plus.
I will do all of that tomorrow then come back and let everyone know how it goes. You guys have been awesome and I really appreciate all the responses.
Outstanding HDF Member
Joined: Dec 2012
Posts: 2,557
Likes: 235
From: Texas
Mine is like an old cigarette smoker, it just has to cough first thing as it is warming up...and especially in a tight-right turn, and I can get a few decel pops occasionally...and only when it is cold. It is ok otherwise.
Thread Starter
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6th Gear
Joined: Mar 2017
Posts: 14
Likes: 0
From: Mid-West
Finished the job.
I just got done fixing the bike today. Some parts took longer than others to come in.
I replaced the intake seals and also discovered that my choke cable was broken at the lever so I ran to my local HD and bought a new one for $14!
As you can see from the picture the seals were more than needed. I buttoned it up and set the idle along with the mixture screw. Ended up at 3 turns out with the idle set at 1000 rpm. I got one cough on the first start up and one more on the initial ride and that has been it. I let it sit for a while and came back to it. It fired right up and I went for another ride and it didnt cough at all
I did however forget to disarm the security system and sat there for a minute stumped as to why it wasn't starting
Overall I'm pretty happy with how it turned out. I hope the issue is gone for good but only time will tell. Thanks for all the advice.
I replaced the intake seals and also discovered that my choke cable was broken at the lever so I ran to my local HD and bought a new one for $14!
As you can see from the picture the seals were more than needed. I buttoned it up and set the idle along with the mixture screw. Ended up at 3 turns out with the idle set at 1000 rpm. I got one cough on the first start up and one more on the initial ride and that has been it. I let it sit for a while and came back to it. It fired right up and I went for another ride and it didnt cough at all
I did however forget to disarm the security system and sat there for a minute stumped as to why it wasn't starting
Overall I'm pretty happy with how it turned out. I hope the issue is gone for good but only time will tell. Thanks for all the advice.
Ultimate HDF Member
Joined: Dec 2007
Posts: 9,254
Likes: 283
From: Lake City, Florida (Native)
I just got done fixing the bike today. Some parts took longer than others to come in.
I replaced the intake seals and also discovered that my choke cable was broken at the lever so I ran to my local HD and bought a new one for $14!
As you can see from the picture the seals were more than needed. I buttoned it up and set the idle along with the mixture screw. Ended up at 3 turns out with the idle set at 1000 rpm. I got one cough on the first start up and one more on the initial ride and that has been it. I let it sit for a while and came back to it. It fired right up and I went for another ride and it didnt cough at all
I did however forget to disarm the security system and sat there for a minute stumped as to why it wasn't starting
Overall I'm pretty happy with how it turned out. I hope the issue is gone for good but only time will tell. Thanks for all the advice.
I replaced the intake seals and also discovered that my choke cable was broken at the lever so I ran to my local HD and bought a new one for $14!
As you can see from the picture the seals were more than needed. I buttoned it up and set the idle along with the mixture screw. Ended up at 3 turns out with the idle set at 1000 rpm. I got one cough on the first start up and one more on the initial ride and that has been it. I let it sit for a while and came back to it. It fired right up and I went for another ride and it didnt cough at all
I did however forget to disarm the security system and sat there for a minute stumped as to why it wasn't starting
Overall I'm pretty happy with how it turned out. I hope the issue is gone for good but only time will tell. Thanks for all the advice.
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Outstanding HDF Member
Joined: Dec 2012
Posts: 2,557
Likes: 235
From: Texas
I wasn't getting a cough problem like you describe but a backfire and decel popping issue that I chased back to the rear intake flange seal. It took a couple of tries to get it all back together with no leaks. I found this technique in a forum discussion and it works like a charm: Put it all together including the air cleaner back plate and carb finger tight only. Then walk all the fasteners down snug tight together then set the final torque.
A set of long ball-end Allen wrenches are a must for a Harley toolbox. Cut off the short end of a regular 1/4 inch Allen wrench to get at the left side intake flange screws.
A set of long ball-end Allen wrenches are a must for a Harley toolbox. Cut off the short end of a regular 1/4 inch Allen wrench to get at the left side intake flange screws.
Last edited by skinman13; Aug 29, 2017 at 10:43 AM.