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DeathTrip
06-12-2017, 6:26 PM
1982 ironhead: I can only get the bike to idle with mix screw out 4 turns and the idle set about 3 turns from engagement point. Anything lower then this and the bike coughs fuel out of the carb. There is a 32 intermediate jet in there now. Stock tear drop air cleaner. Seem to be strait pipes with mufflers, no baffles.
At the above setting I can idle, warm up, make adjustments....even ride. When bike is shut off, won't start again until I return it to the above settings.

Tattooo
06-12-2017, 6:40 PM
1982 ironhead: I can only get the bike to idle with mix screw out 4 turns and the idle set about 3 turns from engagement point. Anything lower then this and the bike coughs fuel out of the carb. There is a 32 intermediate jet in there now. Stock tear drop air cleaner. Seem to be strait pipes with mufflers, no baffles.
At the above setting I can idle, warm up, make adjustments....even ride. When bike is shut off, won't start again until I return it to the above settings.


Have you rebuilt the carb??? Or have you just moved the needles????

DeathTrip
06-12-2017, 7:01 PM
Not rebuilt. Just changed int jet, checked float level, new manifold seals and clamps (seal checked using spray and propane). Replaced o ring on pump ejector nozzle.

DeathTrip
06-12-2017, 7:10 PM
Not rebuilt. Just changed int jet, checked float level, new manifold seals and clamps (seal checked using spray and propane). Replaced o ring on pump ejector nozzle

ridgerunner1965
06-13-2017, 5:40 PM
a 32 int jet seems awful big for a sporty. im running a 0295 in my 80" shovel,have run a 31 but that was just a tad rich.

what do your plugs look like?

if it is a old carb,check for wear at the throttle shaft. if the holes in the carb body are worn it will cause all kinda goofy shit to occur.

ridgerunner1965
06-13-2017, 5:48 PM
pukeing fuel can also be a valve prob. might run thru a pushrod adjustment and then a compression test.

easiest thing to do is switch to another carb and see if results in same symptoms.

DeathTrip
06-14-2017, 3:19 AM
I have done pushrods adjustments. I've been told this could be ignition timing.
I have the rebuild kit for the carb coming this week along with plugs and wires. I'll do the rebuild and timing and post back.
Thanks.

Yes, I too thought 32 was too big. I haven't 295 I'll stick in when I have it off.

pantspisser
06-14-2017, 1:49 PM
Ya man that slow jet is definitely fat for an IH even in the coldest days of winter. A .295 maybe even a .280 is probably what that motor wants. Definitely replace the mixture screw/jet if you have any doubt it's causing this. Those little buggers are cheap and can be easily damaged by a wreckless/overly aggressive wire brush cleaning.

While this issue could be timing related it's unlikely. If the timing is off enough to cause problems it's usually a constant recurring problem not intermittent. Don't rule it out but chase that rabbit later.

Same goes with valve drama. It's possible but unlikely. A compression test is useful but not as helpful as a leak down test. If you're unfamiliar with that test check out YouTube plenty of how-to's there. If the videos create new questions, post'em up here we'll fill in the gaps. I highly recommend getting a leak down test done asap. Having a logged history of leak down test results performed the same way from the same tool is a great indicator of engine health and handy for trouble shooting.

I believe you are on the right path to sorting this problem out by rebuilding the carb. The S&S pdf is very detailed, read it thoroughly. There are no new sins with S&S carbs. They have been around for decades and ever possible breakage has already occurred and consequently every remedy as been created and documented in that S&S pdf.

Don't hesitate to buy a complete jet kit either. While taking CC'ers advice on jet size (mine included) is usually good to go, in truth nobody knows what has been done to your motor in the past i.e. head work, bored out, stroked out etc. All of these things will affect what jet size will work best for you, so it stands to reason having a plethora of various jet sizes on hand is a good deal. The extras won't go to waste either, you or a buddy may need a fresh jet on the side of the road due to piss poor fuel and 9 out of 10 times a jet that is close enough will get you home.

DeathTrip
06-14-2017, 6:15 PM
Thank you Pantspiser, I'll follow up this weekend with results.
You are correct, I have no idea what was done to this motor! Either did the PO, he just bought it for a flip.

Benny74
06-17-2017, 7:08 AM
I have my 74 jetted with 64/28, and I think even the 28 may be a tad too big. Have you gone through the tuning instructions via S&S and reset it each time you rejet?

farmall
06-17-2017, 12:36 PM
I agree with confirming the carb is right (and that you've no fuel tank venting problems) first.

That 32 jet is far too large, and might be someone fucking about trying to correct an air leak they didn't know they had.

As for timing, you can mark the ignition backing plate position for reference with a Sharpie then scribe a line across the Sharpie marks, then move the ignition very slightly retarded and see what changes.

Change timing in very small steps, test start/warmup/idle then test ride if it seems good.

S&S are a bit large for Ironheads but they accumulated as older stock carbs wore out then became the "carb everybody uses". (That sexy teardrop air filter housing sells a lotta carbs.) A later Keihin CV is a better carb for stock displacement Ironheads but S&S can certainly work. I run S&S since I was buying them when they were the main game in town and it's easier to use a standard carb on multiple motorcycles.

DeathTrip
06-17-2017, 7:59 PM
I rebuilt the carb. Set to S&S directions. Found and clean a bunch of hairy crap out of the tank and Petcock. New plugs and wires.
Bike fires, then stumbles and dies.

DeathTrip
06-17-2017, 8:00 PM
But now, at least this occurs with mix screw out 1 1/4 turns instead of 4 like before.

farmall
06-17-2017, 8:19 PM
I've run fuel filters forever and recommend them. Plastic 90-degree auto store versions work well and work better than petcock strainers.

Since you've got the carb cleaned, I suggest tweaking the timing and press on with getting a smaller jet than that 32.

You can solder a jet orifice shut then drill it smaller if you want to experiment while awaiting other jets. The trick is reversible by melting the solder, and on a single carb you don't have to match multiple jets.

Check jet sizes using a drill SHANK, not the flutes, and use a nice smooth drill bit whose shank isn't fucked up. I go by numbered drill size steps. If a #whatever shank is a smooth fit then I'd go up or down one size drill to start. Soldering jets is fiddly because you need to keep the solder in the hole and not on the threads. It's a job for a large iron or a small torch so you may not want to fuck with it but it's an option.

DeathTrip
06-17-2017, 9:47 PM
I should have mentioned that I put the 29.5 in there. Should I advance or retard the timing?

flsjim
06-17-2017, 10:17 PM
I was always tsught pull it back if poppin thru the carb move it ahead if backfiring thru the pipes do as farmall suggested mark it and try a few positions

farmall
06-18-2017, 8:43 AM
If backfire through carb, retard. If backfire out exhaust, advance.

flsjim
06-18-2017, 10:01 AM
Yeah intake tract opening too early or exhaust too late ,someone said tappet adjust.. on solids that kinda makes sense in my experiance it must be close if a harley is too far out of time they wont even pop either way

DeathTrip
06-18-2017, 12:51 PM
Took the carb back off, cleaned the idle/slow again. Re adjusted the float. Bike starts and idles at 2 1/2 turns out with a 29.5. I have to turn the idle up for start, then bring it back to get corrrct idle.
I did adjust pushrods, except front exhaust because I can't break the nut free (starting to round off), I didn't want to make it worse.
When I shut her down, she sputters and a puff of smoke comes out the carb.

flsjim
06-18-2017, 1:13 PM
Get that front exhaust adjusted dk a comp check if good try timing adjust if not you may need to open that cam chest has it ever run for ya?

flsjim
06-18-2017, 1:23 PM
To clarify its alot easier to fuck up a sporty cam chest than a big twin...ive seen basket case bikes with 45 cams tossed in ect.. i ran 3 ch's and an xlh before i got out of harleys and got an evo

DeathTrip
06-18-2017, 2:58 PM
It has, but with mix about 4 turns out, idle way up.

DeathTrip
06-18-2017, 4:06 PM
Get that front exhaust adjusted dk a comp check if good try timing adjust if not you may need to open that cam chest has it ever run for ya?

It has run, got it to idle today but with the idle mix almost 3turns out and idle set way high. Then I had to turn the idle down. Let it idle for about 5 minutes like this. Seemed like I was bypassing my idle circuit altogether at that point. I turned the bike off to eat lunch. Won't start now. Just rumbles.

Since I've noticed that the butterfly won't sit flush...can see light on bottom and sides. Also, I have a gap between the manifold and front cylinder that I can't get rid of. Plugs did look a little gray.

farmall
06-19-2017, 7:16 AM
The way to go is use the intake to align the heads prior to torquing them down, but you can make a simple intake manifold pressure tester if you don't think it's sealing.

When you warm it up do you use the enricher? I didn't notice that mentioned. That's what it's for. What changes with the enricher on? It provides rich mixture for warmup but if you have to run the enricher AND turn the mixture that far out you have an air leak somewhere and/or your butterfly is open too far.

You DID check the butterfly seating by backing off its adjusting screw when checking closure?

DeathTrip
06-19-2017, 10:22 AM
The way to go is use the intake to align the heads prior to torquing them down, but you can make a simple intake manifold pressure tester if you don't think it's sealing.

When you warm it up do you use the enricher? I didn't notice that mentioned. That's what it's for. What changes with the enricher on? It provides rich mixture for warmup but if you have to run the enricher AND turn the mixture that far out you have an air leak somewhere and/or your butterfly is open too far.

You DID check the butterfly seating by backing off its adjusting screw when checking closure?

So, I should move the cylinder head to meet the manifold?
It only runs for a few seconds with enricher on.
Yes, screw backed off. Its like the butterfly is mis-shapen, or the rod it mounts on is. These are fresh out of a rebuild kit.

farmall
06-19-2017, 12:56 PM
Instead of moving heads, I'd solve the butterfly problem first since that's a known defect. A manifold may not mate perfectly but the band may still seal. The manifold seals or it doesn't. One thing at a time. Post a clear pic of the gap with light behind the joint.

Unless the shaft is loose I leave the butterflies alone and have many miles on E's and B's with zero shaft looseness. However since yours is misbehaving attention is needed. If you cannot persuade the butterfly to close something isn't kosher. Did you use an S&S or aftermarket kit? Of course either may not be straight. You can remove the shaft and lay a straightedge against it to check.

You could slightly loosen the butterfly-to-shaft screws, then open and let it snap closed and see if it seats. If you picture the different misalignment options (good shaft but holes slightly off, good shaft with good holes but butterfly holes off, bent shaft fucking everything up, etc) you may be able to determine what isn't right.

What did your leakdown test show? Do that with the manifold off. If all you have is a compression tester (cheap is fine) get a reading for reference.

Got another carb you can test with? Someone who has bushed carbs before could sort out your carb body per the S&S instructions or you could follow them if you have a mill or precision drill press an angle block, reamers etc and know what you are doing, but in your shoes I'd try another carb so you can ride instead of getting into a prolonged fight with the carb. Don't try to work around doing it precisely. If farming it out maybe ya can get an approximate quote from Dragstews.

https://www.sscycle.com/docs/default-source/instruction-sheets/51-1009__throttleshaftbushing_carbs_20131204.pdf?sfvr sn=4

DeathTrip
06-20-2017, 8:18 AM
Thanks for so much input on this. Its really helping.

Solved a couple things last night:
Butterfly seats now, bevel was uneven...couple file swipes and she closes good now.

As I was draining my tank using the petcock, fuel wasn't flowing constant. I set my peanut tank up there and hooked a new fuel line up. Replaced the swivel on the bowl with the new straight fitting that came in the rebuild kit. Bike starts and idles now. I definitely have a leak and/or valve issues. Pipes got cherry red and you can here the chattering pushrods. I did feel a exhaust leak where it meets the head.
I'll fix those two issues I've the next couple days.

I've never done a leakdown test, should I remove valve covers for this?
Can the pipes being hot come from too advanced timing too?

flsjim
06-20-2017, 12:46 PM
Pipes get hot with retarded timing good job dude getting close

flsjim
06-20-2017, 12:55 PM
Your rocker boxes can stay in place I believe it was suggested removing the manifold and do a leak down so you don't push air past those seals which is easy to to with even a bicycle pump

DeathTrip
06-21-2017, 10:11 AM
I got those valves adjusted. Front exhaust needed about 3 turns. Also fixed the front cylinder exhaust leak. Started up and idled great. Plugs a light brown. Sprayed around my manifold seals with propane, seems good. Mix screw out about 2 1/4 turns. Pipes didn't glow.
As soon as I mount this tank properly ill take it for a ride.

flsjim
06-21-2017, 1:16 PM
Far out dude!

farmall
06-22-2017, 7:56 AM
Every mechanic goes through these steps as part of learning.

It can be exasperating but you'll eventually have valuable skill and a properly running motorcycle.

DeathTrip
06-25-2017, 2:40 PM
Finally got time to start tuning...
At idle I could not find intake leaks. However, I'm getting a few random pops out of the pipes. Mostly when climbing Rpms. But also a few when cruising at about 50.
This tells me to go up in jets. Current is 29.5 and 70. However, I can't get past about 60mph, just flat. That tells me to go down on main.
I'm at 3 1/2 turns out on the mix.
I must have air leaking in, right? I'm popping and falling flat.....

flsjim
06-25-2017, 3:22 PM
Try advancing the ignition timing for the fuck of it

DeathTrip
07-07-2017, 6:59 PM
My backing plate is all the way to one end of the slot, can this be filed longer?

farmall
07-08-2017, 12:32 PM
If you are that far out then something else isn't kosher. Don't file the slot, find and fix the problem.

Remove the backing plate and inspect your advance mechanism under BRIGHT light. Pull the points cam and ensure the tiny roll pin is still there and not crushed or sheared off.

Ensure the roll pin which locates the advance mechanism on the camshaft is as it should be.

I didn't search the other posts to see what ignition you are running but points are the easiest to troubleshoot. Set gap, begin with the cover studs in the middle of the slot, then make small movements until it starts easily and runs properly.

Remember total timing is affected by points gap AND backing plate adjustment.

DeathTrip
07-08-2017, 7:44 PM
I have new points, backing plate, and advance mechanism on order. I'll look at that cam tomorrow.
I'll keep you posted. Thanks...again!