oil leak?

[khvatov]

I just bought 2007 VT750C5 with roughly 1700 miles on it. The bike looks very clean and well maintained. When I got it to my house (riding for about 70 miles from the purchase place) after a day I've noticed a few oil spots under the engine. I did not take the bike on the road yet, but I had it idling for a few minutes after a few days. I put some cardboard under it and after two days of just sitting in my garage there were another few spots on the cardboard. I looked under the bike and the bottom had been covered with a little bit of oil (not much though). I opened the rear left cover to be able to assess the leak and noticed that the traces of oil go up the engine block pretty much to the cylinder block. There was a drop hanging from the gear shift spindle as well as one hanging from the oil filter itself.
After 8 hours after I wiped the engine clean (the engine did not run) the bike does not have any signs of leaks.
When I contacted the original owner he told me that he just had an oil change a few hundred miles ago. The oil level looks normal when I last checked it.
The bike is relatively new to have gaskets leak.

Is it possible that the bike has an oil leak? If yes, what could it be?

[tcanthonyii]

Had a similar problem on my 1100 after the rebuild. It ended up being an oil breather hose.

[nraluke]

You say you rode the bike for 70 miles? Air flow from riding will blow a minute amount of oil everywhere. If PO just had an oil change, they most likely reused the old aluminum washer on the oil drain bolt which is causing a leak or could have even forgot to reinstall a washer. I'd get a clean pan and pull the oil drain bolt, save and reinstall the oil, and check the aluminum washer. I have put a thin smear of good red auto silicone on both sides of old drain bolt washers and never had one leak. Also check the oil filter for loose.

[khvatov]

Breather hoses look dry and oil free.

[tcanthonyii]

I would change the oil and as suggested install a new washer, or at a min. make sure everything is tight. I would never ever use oil that I drained from an engine. It's cheap. A little over 20 bucks it's good insurance. Whether or not the PO changed it it would be a good idea to change the oil. He can say he changed it x miles ago but you don't know the guy, you just as well do it right. It's cheap insurance... It's almost always the first thing I do when I buy something with an engine in it from someone.

[khvatov]

Resurrecting my old thread.. I just had the bike serviced. I myself purchased a new crush washer and gave it to the shop tech to get installed when they change the oil. After riding 10-15 miles I noticed that there are still a few drops of oil on the floor. Look like they are coming from the left side. I told about this the shop owner and he said that because the bike has been sitting in PO garage for a while there might be a rubber seal that's leaking oil and it should go away once I start riding the bike more actively.
I'm a little concerned with the leak. Is it possible for a seal to restore its properties once its under use?

[93gc40]

OK you narrowed it to the left side now you just have to figure out where its coming from. NOT something we can do online. Shifters are notorius leak points, also any where a hose or wire goes INTO the motor, and breathers. Gaskets fail for a variety of reasons, especially from disuse. considering this is only a 5 year old bike with ONLY 1700 miles on it, that may be the problem, it spent most of its life PARKED. Clean it and monitor till you find the source.

[khvatov]

Ok, I'm having problems locating that oil leak. The shop owner told me it's most likely coming from the cylinder cover gasket when the engine is running. The oil is not leaking while the engine is off. I made little twisted cords out of toilet paper folded several times and stuck them all around the top cover to find if the oil is coming from there. Nope. I stuck them betweenthe cooling fins at the cylinder gasket - they remaned dry. I had the EOP sensor wrapped in paper towel. After riding for about an hour I get about a teaspoon of oil dripping down as soon as I park. I can see the oil puddles on starter wires, oil goes up to the middle of the cylinder block. Because oil is pretty clear - it's difficult to pinpoint the exact location of the leak. Plust I guess while riding - the oil is being blown by the air all over the place.
Does anyone have any recommendations on how to detect the source of oil leak?

[MarineCorpsFlorist]

There is a dye you can add that lights up under black light, Go to autozone or where ever, buy the kit, add to oil, run for a few minutes (stationary so wind doesn't blow it around) and use the black light to find it. It glows so it will be easy to see. You'll need to change oil after to get the dye back out. You should see it start to ooze thru a gasket after a few minutes of running.

Of course once you know where it's coming from you should get a lot more help fixing it on here.

Amazon.com: Tracer Products TP34000601 UV Fluorescent Leak Detection Dye - Set of 6: Automotive

Amazon.com: Tracer Products TP34000601 UV Fluorescent Leak Detection Dye - Set of 6: Automotive

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http://www.silver-seal.com/product/1...-Dye-1-oz.html

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http://www.tysol.com/leak.html

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[khvatov]

Thank you. I'll do that.