Gas consumption is way too HIGH, Mileage too low

[jetmechmarty]

Sorry but I meant 20W-50 motor oil.

That's the stuff!

[TopCatGr58]

Hey Rich,

Like you said, even though #2's comp's are a little lower than the others, it's not that much, especially with a freshly honed engine. You probably need to put a few more hundred miles on it, especially with the NEW coil to see IF the cylinder plug fouls again. Hopefully the rings will seat a bit more to help prevent the oil leakage past the rings. Low comp could allow more oil into the cylinders past the rings...but I can't believe it's allowing that much to foul the plug. ALso, I thought you rebuilt the head....lapped the valves and new valve oil seals? IF you didn't, then that would/could be another source of oil into the cylinders. I don't think you need to worry about the hint of fuel smell in the oil just yet.....with low comps you can get a bit more blow by the rings, and these engines have wider clearance tolerances anyways, that's why the oil gets contaminated after just a few thousand miles.

The test ride with the new coils will tell alot. IF the plug fouls again, then there's more info towards actual oil fouling vs. faulty ignition. But hopefully it won't foul, and with more miles you'll seat the rings a bit better.

Smoking cold engine....again, could be leaky valve seals that ooze after sitting so more oil in cylinder when first starting. Once engine warmed up, valve expands along with compression helping to seal better.

T.C.

[RichV]

If did lap the valves and replaced the valve seals. If the oil change and coil change doesn't fix the problem, I'll have to pull the head and look at everything.

Tomorrow, I'll go for a ride and see if the seal still leaks and the plugs fowl. If it does, I can replace the seal again (3rd time).

[RichV]

Well I put in the new left seal and everything was fine for the first hour. Then the leak came back. Not as bad as before but it was still there.

As for the engine. It started out great and ran smooth for about 20 minutes. Then it started to run rough again. It reminded me of in the past when I would get bad fuel. I tried adding a higher octane but that didn't seem to calm it down.

I removed the plugs and, once again, #2 had oil on it (not much). The others were fine. I also looked into the cylinders and they all looked clean including #2.

I've put almost 400 miles on the bike since the new rings and I changed the oil and filter just before the ride. I'm going to continue to ride it for more than 200 miles to see if it changes.

The only thing I can think to do is remove the head and recheck the valves and seals. I can also look at the valve clearance. Since I have to remove the carbs, I'll check the jets and make sure they are seated properly and recheck the float height.

[TopCatGr58]

Hey Rich,

Well, it looks like you've narrowed it down a bit....not the coils, caps. The fouling sounds like it's OIL. Doubtful that it's the valve seal...the engine compression prevents it from leaking much into the cylinder. But with worn OIL RINGS...the intake stroke can allow it to leak past the oil rings and the compression/scrubber rings and into the comb. chamber. Even with good compression, ...comp rings are angled to prevent pressure getting past from on top of the piston, not so much to prevent "stuff" from getting past them from below the piston....hence why they also have scrubber rings and the oil rings!

So....yes, keep putting in new/cleaned plugs and ride it to see if the rings may seat better and seal it a bit more to prevent the oil seepage???

So....I don't think you need to remove the head. You can visually inspect the intake valve from the intake port side by just removing the carbs....and so you can see IF you can see much oil on the valve shaft of the #2 carb vs. the other cylinders. IF there is more oil, THEN you can assume that the new seal somehow got damaged. IF there isn't any extra oil vs. the other cylinders, then the oil is coming from/past the rings and not from the valve=no head removal!

T.C.

[RichV]

I also have a left seal leak I can't seem to stop. The engine starts to run rough and the seal leaks after that. I don't know if they are related.

Do I need to replace the plug or can I just clean it after every ride? Can I just replace the fowled one?

[BA80]

I also have a left seal leak I can't seem to stop. The engine starts to run rough and the seal leaks after that. I don't know if they are related.

Do I need to replace the plug or can I just clean it after every ride? Can I just replace the fowled one?

Left seal?

[RichV]

Left seal?

Yep. I've put three in and all three have leaked to one extent or another. The last one the least of all. I put a coat of RTV on the outside edge and pushed it in slowly. I made sure there was a lite coat of oil on the inside.

After about 25 miles, my boot starts to look wet. When I stop, it marks it's territory with a dime size drop of oil. When you take the cover off you don't see much oil on the seal. Just a little bit.

Nothing bugs me more than leaky seals. Well, Nazis bug me more but leaky seals are a close second.

[TopCatGr58]

Hey Rich,

I would think/hope that you can get by with just cleaning the plug, you can tell quickly whether it's firing or not when you fire it up. Since the others are burning properly, just leave them alone. Just be prepared to replace the #2 with NEW because the carbon in the oil can get cooked/burnt onto the insulator and cause a short track that may not be cleanable with just carb cleaner....don't know if you have one of those fancy sandblast box/chambers for cleaning plugs??

Did you see the post by Tod regarding the crank seals that have dual seals/edges vs. the OEM style that uses only 1? Due to wear at the sealing edge from the old seal....a little groove can develop on the crank that can prevent a new seal from making/maintaining a proper seal. The newer different seal uses 2 seal edges that are in different locations to reduce the tendency of it trying to use the same old seal/groove!

I remember years/decades ago about V-8 crank seal kits that even used a little slip sleeve to provide a new flat sealing surface around the crankshaft since a groove is often formed with old engines.

Also, with the seal out, can you see the sealing surface of the crankshaft? OR even feel around it to see if you can feel a burr or rough edge/surface?? Perhaps run some emory cloth around it??

T.C.

[BA80]

Left seal?

I assume you mean the crankshaft seal.

If you've replaced that seal repeatedly and it still does the same thing common sense says the leaky seal is a symptom of the disease, not the disease itself.

The fouled plug is most likely a sign.

Have you done a compression check?

[RichV]

I would think/hope that you can get by with just cleaning the plug, you can tell quickly whether it's firing or not when you fire it up. Since the others are burning properly, just leave them alone. Just be prepared to replace the #2 with NEW because the carbon in the oil can get cooked/burnt onto the insulator and cause a short track that may not be cleanable with just carb cleaner....don't know if you have one of those fancy sandblast box/chambers for cleaning plugs??

No fancy box here. It's true that the insulators are turning black and are not cleaning off. I have a bunch of plugs I can continue to try. The bike always sounds okay when I start it and it idles just fine. It's when I get out on the road I notice the problem. I get about 20 miles down the road and it starts to run rougher. I can continue to ride and it just becomes annoying but doesn't get much worse. I clean or swap out #2 and it goes away for 20 miles. I've labeled the plugs so I don't get confused. The #2 plugs have sub numbers like #2, #2.1, #2.2, ... I have plenty of extra plugs for now.

Did you see the post by Tod regarding the crank seals that have dual seals/edges vs. the OEM style that uses only 1?

Yes i read the post. I bought the dual seal ones.

[QUOTE=TopCatGr58;469504]I remember years/decades ago about V-8 crank seal kits that even used a little slip sleeve to provide a new flat sealing surface around the crankshaft since a groove is often formed with old engines. /QUOTE]

You can still get the sleeves. They're just hard to work with and usually have to be trimmed. Timkin makes them. There's also Speedi-sleeves which I heard someone else mention in the forum. Supposedly they use the same seal.

Also, with the seal out, can you see the sealing surface of the crankshaft? OR even feel around it to see if you can feel a burr or rough edge/surface?? Perhaps run some emory cloth around it??

I noticed last time there were some corrosion pits in the surface. This shaft came from the bike that was flooded and it's possible that water go into the seal and caused the pits. I cleaned it with a brush last time and tried to get it smoother. I think using the emory cloth would be a last resort.

I'm thinking something else may be going on here. Is it possible that the oil pressure is too high? Could that cause the blow-by on the rings and the leaky seal. We may be looking at two sides to the same problem. The oil level is between the two marks when on the centerstand. I would also think the crankcase vent would stop this.

[RichV]

Have you done a compression check?

Yes, not as high as I would like but good enough until the new rings set in.

[jetmechmarty]

You need to make sure you aren't losing spark to #2 when running down the road.

[RichV]

You need to make sure you aren't losing spark to #2 when running down the road.

How do I do that? I've swapped out most all of the components. What could cause that to happen?

[jetmechmarty]

I it still rough when you stop and idle? See if #2 fires a timing light,