• 4 Stroke Husqvarna Motorcycles Made In Italy - About 1989 to 2014
     TE = 4st Enduro & TC = 4st Cross

  • Hi everyone,

    As you all know, Coffee (Dean) passed away a couple of years ago. I am Dean's ex-wife's husband and happen to have spent my career in tech. Over the years, I occasionally helped Dean with various tech issues.

    When he passed, I worked with his kids to gather the necessary credentials to keep this site running. Since then (and for however long they worked with Coffee), Woodschick and Dirtdame have been maintaining the site and covering the costs. Without their hard work and financial support, CafeHusky would have been lost.

    Over the past couple of weeks, I’ve been working to migrate the site to a free cloud compute instance so that Woodschick and Dirtdame no longer have to fund it. At the same time, I’ve updated the site to a current version of XenForo (the discussion software it runs on). The previous version was outdated and no longer supported.

    Unfortunately, the new software version doesn’t support importing the old site’s styles, so for now, you’ll see the XenForo default style. This may change over time.

    Coffee didn’t document the work he did on the site, so I’ve been digging through the old setup to understand how everything was running. There may still be things I’ve missed. One known issue is that email functionality is not yet working on the new site, but I hope to resolve this over time.

    Thanks for your patience and support!

Deep heavy black carbon soot on spark plug, how 2 check test compression

wardro

wardro

Husqvarna
AA Class
Lately my 2007 TE510 hasn't been itself. I have notice that my spark plug is fully covered in deep heavy thick black carbon soot. I have bumped up the heat range and installed a fresh new air filter, changed the oil, but same problem. I haven't done a thing with the carb jetting, I figured it shouldn't be a problem since it has been fine for the past 5 years. I tried to do a compression test but because of the auto decompression feature I could only get about 80 psi from the reading.

Any suggestions? I only have about 6k miles on the bike. Does anyone know how to actually perform a full/correct compression check without the interference of the auto-decompression feature?

What else do you suggest, what are my options?

Thanks in advance, Ron:confused:
 
Just as an update, I removed the muffler and ran it without any backpressure for about 3 minutes. I didn't see any smoke at all during the test. I check the plug again and fully coated with black powder soot. Does anyone know if I can determine if the black soot is from oil or gas? If I can determine that it is fuel then I know I just have some carb. problem. Please let me know if you have any advice, suggestions, concerns, etc.

Thanks, Ron
 
Check the carb for a dropped down emulsion tube/main jet, or if the enrichener is stuck open, or if the pilot jet has dropped out.. The black soot is likely from too much gas. Below is a pic of a friend's Beta that the emulsion tube/main jet came loose and the bike ran like crap, getting too much gas.

carb_041213.jpg
 
Good suggestions. I smelled the plug but didn't get much so I smelled the muffler and very much of a gas smell. I have also included a picture. I have other plugs that were much worse (coated in black soot) but I already cleaned them. Tomorrow I plan on opening up the bowl as suggested to see if anything obvious is seen. Thanks for the support.image.jpg image.jpg
 
That looks way rich and definitely not oil fouling. The fact that it is dry/fluffly looking soot tells me that the spark is good and trying to fire it. Usually weak spark with result in a wet plug. Your bike is old enough to have needle and seat wear as well as the "O" ring around the float seat could have started to let fuel by. If you've been running pump gas with any ethanol in it the float could also be breaking down and absorbing fuel causing it to be heavy and allowing the fuel level to rise.
 
Update, got the carb off and it is very dirty on the inside. Ordered a rebuild kit and once finished will give update. Thanks for the support. R
 
These bikes are super rich from the factory too. My 06 510 would barely run at lower throttle. (Way too big of a pilot jet) Also they have a plugged leak jet from the factory so the Accelerator Pump shoots in way too much gas. JD Jet kit is your answer. I just finished putting mine in and the bike runs about 10 times better and smoother at all rpms. Comes with the proper size pilot jet (45) and about 4 different main jets. Also much better needle and a functioning leak jet.
I would highly recommend it.
 
OK got a status.
1.) ordered a rebuild kit from JD Jetting, and rebuilt carb with all the parts. Cleaned everything, blew it out, looks like new again. Didn't change any jets or needle position. Only checked the float height 9mm so all looked good. Installed carb, same problem deep black soot even blowing out exhaust now.

2.) Called JD Jetting, he said to make sure the float height is correct. So removed carb again, checked float height exactly 9mm, did both test with leaning the carb and blowing into the fuel line. I even took time to make a special template. So float is correct. Then I remember I once had a box of JD Jetting from the original owner that he gave me when I purchased the bike years ago. Go the box out and inside was the instructions for the kit. Basically to use Red needle, 180 jet....etc. So what I found out was that the needle was in position 6 from top. The instructions say to use position 5 from top. So I changed that. It also said to make sure the fuel screw (the one at a angle at bottom of fuel bowl on engine side) is at 1 1/2 turns. Mine was at 2 turns. All the jets were as per the instructions. So I made those changes put back together. 5 minute ride, no black soot/smoke, however did have some hesitation right off start and some popping after releasing throttle. When back to garage, checked plug, NO SOOT. Finally a good change.

3.) Turned the fuel screw to 1 3/4 turns, change the spark plug back to factory (had been running a hotter plug), put a fresh clean filter (not to much filter oil) and tried another test. Great power, no smoke just a tad bit of hesitation and some popping. Checked the factory plug, looked excellent no soot.

4.) So now I have turned the fuel screw back to two turns and need to do a test to verify my problem is resolved.

So summary - carb needed cleaned, needle in wrong position, and possibly the air filter too oily. Thanks for all the support and advice.
 
It sounds like your pilot jet is still dirty. The fuels of today leave a clear hard coating in all the small holes of this small jet. Carb cleaner and air will not clean them out. Replace it with the same size jet to be sure.
Also , the popping on deceleration may be from a leaking exhaust gasket, if the pipe has ever been removed.
Popping on acceleration is the pilot jet.
2 turns out on the fuel screw should be about right.

Paw Paw
 
Thanks Paw Paw -
Funny thing is that I have never had a popping during deceleration until I changed the position of the needle and the fuel screw. I haven't ever removed the exhaust from the head, only the muffler from the exhaust pipe once.

If still have problems after the last test will get another Pilot Jet and verify exhaust fitting.

Thanks for the support.
 
You must log in or register to reply here.
Back
Top