A Problem, an Answer, and a Question!

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SS109
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A Problem, an Answer, and a Question!

Post by SS109 »

The Problem: My 220, that I rebuilt last summer, recently started to really spooge bad (my bike normally never spooges!) and my power fell off. Figured the jet block gasket was shot so I replaced it and, since I didn't replace them during the rebuild, I put in some new Boyeson Pro Series reeds in the RAD Valve. Sadly, this did not fix the problem. Figured it might be the exhaust problem again so I decided to repack the silencer. Get it apart and, nope, not the problem. Hmm, what are these chunks in there? They're not carbon. They're aluminum! :shock: Crap, time to start tearing down the engine to find out where they cam from.

The Answer: Get the head removed and the piston head and cylinder head look good. Then I see it, where a left subvalve should be sticking up through the collar there isn't one. So, on to removing the whole cylinder. Piston looks undamaged as does the cylinder. Whew! Looks like everything made it out the exhaust without killing anything else. How? I don't know but I'm pleased it wasn't worse. Time for new left subvalve, base gasket, head gasket, and with a little cleaning she'll be back to ripping! :boogie:
subvalves.jpg
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The Question: With that figured out I noticed my carbon pattern on my piston and cylinder head. Looks to be rich. Thinking I might step down one main jet size to a 150. Pilot jet is already at a 40 so I don't plan on changing it. What say you? Does going down a step look like the right call? :hmm:
piston wash.jpg
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head wash.jpg
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Re: A Problem, an Answer, and a Question!

Post by John_S »

Good job checking over the bike thoroughly to see what was wrong. I can't believe all that sub valve is missing and theres no damage. You must be living right as they say. What a relief!!
If your bike typically never spooges then you must be really close to dead on and might want to leave well enough alone. Even when I think mine is jetted great I'll get a little something at the end of the silencer. It'll happen just riding around on the needle so its a touch rich which is ok. I would do a plug chop with the current main jet and see what you think from there. If I don't have a lot of room I'll take off from the truck and do a 1st-4th wide open until it no longer pulls, pull in the clutch but not kill the engine, then turn around and blast back to the truck 1st-4th killing the engine that time, so two wide open runs. Being on the pilot circuit for the few seconds it takes to turn around doesn't discolor the plug enough to matter. I've done the same thing at half throttle (maybe 4 times out from the truck and back) to get a general idea of how the jetting is on the needle and not have to cut the plug. A brand new plug should already be "coffee with creamer" colored even in that short time on the needle. My 220 (35mm carb) has a 148 in it now, 40 pilot, 2nd clip JD red but if I put a 155 right now at 80 degrees, sea level, and did a plug chop a brand new plug would be black from the base of the porcelain almost all the way to the tip.

How much run time is on that spark plug? The porcelain looks too white to me on the pilot and needle. It could just be the flash of the camera making it look light.
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Post by thirdgenlxi »

Daaannnnggg, that's crazy!! Glad it didn't do any damage.... it most definitely could have! haha. Good job finding that. I'm curious to see what mine look like when I take it apart
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Re: A Problem, an Answer, and a Question!

Post by KDXGarage »

I am glad you got by on that one. Canyncarvr had some thing similar ten years ago.

Do a plug chop or two and see about the main.

How many hours are on the piston? It looks a bit caked up with carbon.
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Post by SS109 »

Thanks guys. Yeah, the plug looks lean which is odd. Sorta has a pale yellowish tan color to it. The one I pulled indicated rich but was almost a year old. I just put in the plug in the pic when I did the jet block gasket and reeds. It has just over 100 miles on it as I was sweep rider for our race on Saturday. I rode a lot of high speed sand washes and my bike just wouldn't rev out and had no power. Had to actually use 1st gear to get up every hill (even the super easy ones) where normally I'd be in 3rd.

About jetting, what drew my eye was the wash pattern on the piston top and the head. That much wash indicates too much fuel. The carbon build up is because I use Castor 927 which has a very high flashpoint and I don't wring it out enough on every ride. I could probably go to a full synthetic to get a more complete burn but I love the protection 927 provides and especially so in the hot summer months. Maybe I'll do the crazy thing and go to a 50:1 ratio and rejet for it. Of course, first I must get her back together and running again. Did I mention those freaking subvalves are expensive? $68! Ouch!
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Re: A Problem, an Answer, and a Question!

Post by newbbewb »

Drop your gearing and rev that thing out :grin:
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A Problem, an Answer, and a Question!

Post by Jim B »

SS109 wrote:The carbon build up is because I use Castor 927 which has a very high flashpoint and I don't wring it out enough on every ride. I could probably go to a full synthetic to get a more complete burn but I love the protection 927 provides and especially so in the hot summer months.
I don't want to start a two stroke oil debate, but the broken subvalve (on the right in the first picture) is REALLY carboned up. No way to tell for sure, but I suspect that's why it broke. (The carbon caused a lot of resistance to rotating.) Also, the bottom part of the subvalve on the left in the first picture seems to have a lot of wear. (It kind of looks like it's been polished.) I recently took apart the top end of my 220 that had nine years of use on it. All the powervalve parts either wiped clean with a paper towel, or took just a little bit of carb cleaner to clean. If it was me (and it's not) I'd switch to something different.
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Post by KDXGarage »

Jim B wrote:I don't want to start a two stroke oil debate, but
TASTES GREAT!

...LESS FILLING!

TASTES GREAT!

...LESS FILLING!

Anyone under 40, please excuse me. LOL :partyman:
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Post by SS109 »

newbbewb wrote:Drop your gearing and rev that thing out :grin:
It's already dropped. I run 13/48! :mrgreen: Sadly too much high speed sand out here to go any steeper. The 250 and larger bikes can speed away from in the sand washes already.
Jim B wrote:
SS109 wrote:The carbon build up is because I use Castor 927 which has a very high flashpoint and I don't wring it out enough on every ride. I could probably go to a full synthetic to get a more complete burn but I love the protection 927 provides and especially so in the hot summer months.
I don't want to start a two stroke oil debate, but the broken subvalve (on the right in the first picture) is REALLY carboned up. No way to tell for sure, but I suspect that's why it broke. (The carbon caused a lot of resistance to rotating.) Also, the bottom part of the subvalve on the left in the first picture seems to have a lot of wear. (It kind of looks like it's been polished.) I recently took apart the top end of my 220 that had nine years of use on it. All the powervalve parts either wiped clean with a paper towel, or took just a little bit of carb cleaner to clean. If it was me (and it's not) I'd switch to something different.
The carbon build up could account for the failure however I believe the build up occurred after it was broken. Notice the right valve isn't carboned up anywhere near as much and I can't think of a reason that one would and the other not. Don't think it was the 927 as I have been running it for years and never had a problem snapping subvalves or anything getting really carboned up. I think all that carbon could be from when I had an exhaust problem where the internal perforated pipe in the silencer broke at the front which allowed the packing to block it and was choking the engine. That allowed a lot of oil and fuel to build up in that area yet not completely burn. Plus, the same happened kind of again after that subvalve broke. Yet, it and it's associated collar came out without and binding or grit. Same for the rest of the power valve system. Well lubed and smooth. The only thing I changed during the rebuild is that the ball and spring was missing on the left side so I ordered replacements and installed them. Wondering if I should have just left them out? Hmm.

Here is a pic of the subvalves again but after I sprayed the right one with Awesome cleaner (I avoid harsh chemicals at all cost) and scrubbed with a paper towel and fingernail. Doesn't look that bad IMO.
wiped down subvalve.jpg
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Post by Jim B »

SS109 wrote:...I believe the build up occurred after it was broken. Notice the right valve isn't carboned up anywhere near as much and I can't think of a reason that one would and the other not.
Excellent point! I wonder if a synthetic would have carboned up like that, in the same situation. :hmm:

SS109 wrote:(I avoid harsh chemicals at all cost)
Harsh chemicals are the best chemicals! (At least the ones that work really well.) I love carb cleaner, brake cleaner, Goof Off, lacquer thinner, enamel reducer, etc. :rolleyes:
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Post by SS109 »

Jim B wrote:
SS109 wrote:...I believe the build up occurred after it was broken. Notice the right valve isn't carboned up anywhere near as much and I can't think of a reason that one would and the other not.
Excellent point! I wonder if a synthetic would have carboned up like that, in the same situation. :hmm:
Probably would have been less with a lower flashpoint synthetic.
Jim B wrote:
SS109 wrote:(I avoid harsh chemicals at all cost)
Harsh chemicals are the best chemicals! (At least the ones that work really well.) I love carb cleaner, brake cleaner, Goof Off, lacquer thinner, enamel reducer, etc. :rolleyes:
LOL! Yeah, too many years wrenching on cars and bikes for fun and profit that I try to stay away from them. Still use them and will go through some brake clean getting it all ready to go back together.
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Re: A Problem, an Answer, and a Question!

Post by KDXGarage »

" I think all that carbon could be from when I had an exhaust problem where the internal perforated pipe in the silencer broke at the front which allowed the packing to block it and was choking the engine. "

Hard to pinpoint with that in the mix. Is it an oil problem, mechanical problem, both??

If you use E-Z Off oven cleaner, DO NOT let it set long on aluminum. It will eat it up. Spray some on aluminum foil then brush or Q-tip it on??
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Re: A Problem, an Answer, and a Question!

Post by Jim B »

Jason wrote:If you use E-Z Off oven cleaner, DO NOT let it set long on aluminum. It will eat it up. Spray some on aluminum foil then brush or Q-tip it on??
Easy-Off on the steel parts and liquid gasket remover works pretty well on aluminum.
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Post by KDXGarage »

Anyone ever try a toothbrush, nylon bristle brush (cheapie Harbor Freight one) or wooden scraper (toothpick or such) to clean the carbon off the gears?
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Post by thirdgenlxi »

If you guys want a fantastic cleaner for cleaning carbon and whatnot, that won't hurt the metal..... this stuff right here. I was a Ford dealer diesel tech for 12 years, and I used this stuff religiously for cleaning diesel EGR valves that were caked up with thick layers of carbon, plugged intake manifolds (EGR ports), MAP sensors that were clogged with carbon, VGT turbos, etc. All kinds of stuff. It's a foam, so just spray it on and let it soak for a little while.... it literally just dissolves carbon and pretty much anything else gunk wise. Wipe it down with a rag and it looks like new again. I've used it on nasty carb bowls and jets before too, including my buddies dads old AJS that hadn't been run in 30+ years, with the old "gas" still in the carb (naassstttyyy!!). It's seriously awesome stuff. I haven't worked at the dealership in almost 3 years now, and I still keep a couple cans in the garage cuz I haven't found anything else that works as good. Can get at your local Ford dealership parts dept, or ebay/amazon. A little pricey but worth it. Lasts quite awhile too being a foam



My can here is a little dingy, but PM-2 is the part #

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Image0309180326_HDR by Jared Penttinen, on Flickr
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Post by KDXGarage »

LOL!! It says on the picture on Amazon, not for use in diesel engines. :lol: :lol: :lol:

Drink up. :drinkers:

2-BUTOXYETHANOL (CAS 111-76-2)
4-METHYLPENTAN-2-OL (CAS 108-11-2)
CUMENE (CAS 98-82-8)
NAPHTHALENE (CAS 91-20-3)
Solvent naphtha (petroleum), heavy arom. (CAS 64742-94-5)
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Post by thirdgenlxi »

Jason wrote:LOL!! It says on the picture on Amazon, not for use in diesel engines. :lol: :lol: :lol:

Drink up. :drinkers:

2-BUTOXYETHANOL (CAS 111-76-2)
4-METHYLPENTAN-2-OL (CAS 108-11-2)
CUMENE (CAS 98-82-8)
NAPHTHALENE (CAS 91-20-3)
Solvent naphtha (petroleum), heavy arom. (CAS 64742-94-5)
That's because it's original intent is to be sucked in through the intake and used as a top end cleaner while the engine is running, which you cant do in a diesel because it will act as a fuel and run away, the same as spraying brake cleaner in the intake. But using it as a standalone parts cleaner is perfectly fine
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Post by Jim B »

thirdgenlxi wrote:If you guys want a fantastic cleaner for cleaning carbon and whatnot, that won't hurt the metal..... this stuff right here. I was a Ford dealer diesel tech for 12 years, and I used this stuff religiously for cleaning diesel EGR valves that were caked up with thick layers of carbon, plugged intake manifolds (EGR ports), MAP sensors that were clogged with carbon, VGT turbos, etc. All kinds of stuff. It's a foam, so just spray it on and let it soak for a little while.... it literally just dissolves carbon and pretty much anything else gunk wise. Wipe it down with a rag and it looks like new again.
Wow, great info! :supz: I didn't even know something like this exists; I always just use cheap-o regular Walmart carb cleaner. Takes a bunch of time and work. I can see how this would be really handy if you worked on the 6.0 on a regular basis. I've got to pull apart the engine in my SAAB in the next few weeks; I'll probably pick up a can of this to clean the combustion chambers.
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Re: A Problem, an Answer, and a Question!

Post by KDXGarage »

Will it work to clean old spark plugs?? I might need to buy a case. :razz:
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