Thick brown paste in my carbs? FIXED!

[isaac]

Two hours and thirty minutes after cranking my bike to take off from the office today, I finally packed it in, got a ride home, and put it into the back of my van to tow back.

That's 150 minutes of cranking my bike 20 seconds, letting it rest a couple, then cranking again. For those who've been following my bike's recent trevails, that's obviously a major regression from the recent 5 minutes of cranking my bike has required for the last week, and much worse than the 5 seconds of cranking to start it that my bike had needed for the entirety of my ownership of it before that.

The 5 minutes cranking time before it finally kicked enough times in succession to start up began 2 days after I got it running again last week. I drove it for those first two days and it was fine - started right away, ran great - though the same high idle as always. It wouldn't idle below 2,000 without dying, but otherwise was great.

So the problem rapidly has gotten worse until today. The start from a dead cold to get it going this morning took 5 mins. The bike ran fine the whole way there. 5 hours later, it didn't start again.

I got it home today and immediately started ripping into the carbs from memory of the pics on here. I knew something was weird right away when none of the bowl drains produced any gas.

I seperated the carbs and disassembled #1. The bowl had so much of this weird brown paste in it that the drain was completely covered up. It was all over the bowl as well, with a little of it in the main and idle channels.

I yanked the idle jet and ran it through with a small sewing needle and it didn't seem very plugged. Needless to say this has me worried since I was under the impression that plugged idle jets would cause the no start. Is there a passageway inside the carb body that supplies the idle jet that is as small as the jet holes? What should I do? Thanks for the help.

PS, where can I buy carb boots?

[Anonymous]

Sounds like old gas may have gone to varnish. Did you store it over the winter with gas in it, and without any stabilizer? If so carb dissasembly, clean and dip will be needed.

If its just a hard starting issue, I had that begin quite suddenly with my '82 GS100EZ. Would crank and crank when cold, but just not 'catch'. Turned out I needed a new battery. Started very quickly after that was replaced, end of problem.

[isaac]

Thanks for the response. I don't know much of the bike's history. The PO purported to have "fixed it up" while he had it, but I guess that didn't mean cleaning out the bowls. The bowl gaskets, some o-rings, the CV diaphragm and one of the carb to head boots is new.

I bought it in Nov and since then it'd run fine until the igniter incident took the bike down for more than 2 months.

I just bought a new battery and have been tending it nonstop too.

Update on the carb teardown: The choke circuit feed in the bowl may have been plugged, but you can't exactly see in there. I'm spraying everything out with carb cleaner and soaking the small parts. Still nothing obvious coming up that points to why the bike didn't start.

[Anonymous]

Just did 2 sets of carbs on my Suzuki and Kawasaki. You want to get it done right the first time so you don't have to do it again! Don't ask me how I know this.

The best way is to disassemble everything and dip it in carb cleaner fluid. You can get it at auto parts stores. Make sure and get ALL parts with rubber or o-rings removed first, as the carb dip will deteriorate them.

[DMPLATT]

Since your bike cranked for that long, WOW. You have one hell of a charging system.

I'm no expert, but sounds like, since you've done the carbs before, float heights are wrong.

:?

Should be enought fuel in the bowls to at least fire.?

[sv650]

Re: Thick brown paste in my carbs? WTF, mate?

I knew something was weird right away when none of the bowl drains produced any gas.

I seperated the carbs and disassembled #1. The bowl had so much of this weird brown paste in it that the drain was completely covered up. It was all over the bowl as well, with a little of it in the main and idle channels.

First hint -- no gas in carburetor bowls.

Second hint -- brown paste in bowl #1 (no comment on others, have you checked?).

Time to drain gas tank, and remove petcock. Above the petcock is a fine strainer, that is likely clogged with rust particles, the finest of which are finding their way into the carburetor bowls.

Your mission: remove rust from tank. See many articles on this site for more info on this topic. I personally prefer the vinegar and CLR method, but others have their favourites as well.

You may wish to add a gasline filter upon reassembly.



SV

[Hoomgar]

Yup, sounds like rust deposits. yuck!

Clean her up man. The advice above is good. Do the tank and the carbs. You'll be glad you did.

[isaac]

Alrighty, thanks for the help. I'm most of the way done here. To clear things up: fuel didn't flow out of the bowl drains because the drains were clogged, not because there was no fuel. When I took the bowls off, lots of gas went everywhere. I've got two inline fuel filters, and the fuel flows fine. This is my first time ripping open any carbs ever, so it's all new to me.

All three of the other carbs had a lot of the brown goo in the bowls, which may have been heavily obstructing the choke passageway and maybe the idle jet. I didn't see any holes fully plugged though, which is disconcerting considering how bad this had gotten.

I'm almost done with it though. I just put together the last one, and am reassembling them. I plan on firing the bike tonight.

If this doesn't help, you can be damn sure I'll be checking everything else listed here. I really do need to clean out the rust in the tank, though it's not too horrific. How does the CLR and vinegar trick work?

At the moment I'm a bit confused about the arrangement of the carbs to put em back in a row next to each other, particularly the throttle valve actuators.

Thanks again for the help!

[Sandy]

After you've cleaned everything up make sure the orfice in the bottom of the choke reservoir in the float bowl is not plugged and will actually flow fuel. With the float bowl off, partially fill it with fuel to see that it is actually seeping into the choke reservoir. You may need to poke it with needle and use lots of air to actually unplug that little sucker. I got really good at removing my carbs before I found that one. LOL.

[isaac]

Sandy, thanks for that tip. I think I may have taken care of that if I know which passage you're talking about. It's the little hole at the bottom of the bowl that has a connecting passage that goes directly into the choke? If so, I made sure I blew the hell out of those. A couple seemed pretty plugged.

I just put the carbs back in and attempted to start the bike. It's kicking a hell of a lot more than it was before I did all this, but it's still not firing. I have no doubt based on the kicking alone that it'll fire within five minutes, but that's still a lot worse than it used to be.

So...back to square one? How about the float heights? What's the quickest way to make sure those are set correctly? Thanks for the help.

[isaac]

IT LIT UP! took forever though.

It also idled at 2,000rpm cold!

My back hurts. I'm going to bed.

[isaac]

Well the bike appears to have tricked me into unwittingly giving it a full carb service.

I cleaned everything thoroughly last night, dipping the small parts and blasting out passages repeatedly with carb spray. I put it back together last night and after a LOT of cranking it lit up. This was about the same problem as before - it just hit like it was going to start more often. Start time approx 8 sessions of 20 second cranking each.

So today I yanked the carbs again after cranking it over and over again and finding that only the #2 exhaust was getting warm. I didn't see much difference in the float levels but I adjusted the other 3 upward slightly. I also richened up the air screws a bit.

I put it back together, and it once again barely started, though more easily than before. Start time approx 4 cranking sessions of 20 seconds each.

Then I went and bought some new spark plugs to replace the normally worn (but still good looking) Autolite 4163s. They had been giving a blue spark in testing the whole time.

I put them in, replacing all 4 plugs. I cranked the bike and it literally started half a second later, settling into a 2,000 rpm dead cold idle (only partially choked). So, the bike made a monkey out of me, and runs great.

[sv650]

How does the CLR and vinegar trick work?

Thanks again for the help!

See:

http://www.thegsresources.com/_forum/viewtopic.php?t=23677

Now thatthe bike runs, you can work on addressing the brown goo......

SV

[duaneage]

I dropped a new set of plugs into my 650 last month and it made a hell of a difference. Worth 7 dollars IMHO.

I fixed a lot of carb problems with a new set of plugs back in the day

[crash]

This might be a stupid question, but where do you dispose of the gas that's been sitting in the bike all winter? (Legally, thanks.)