Oil seepage at front of engine casing

[blueridge]

I purchased my 2010 NT700 at the beginning of June with just under 7000 mi. It currently has 8500 mi. Getting
set up to do my 8000 mi. maintenance. Notice some oil seepage at the front of the engine casing. (see picture).
Thought I got a fair price on the bike ($3600). Now I'm starting to worry I was sold a problem. How worried should
I be? Thanks in advance.

 

[ColoradoRod]

That looks pretty minimal. That might be the sum total of leakage from the day it left the factory floor. You never know if the prior owner ever wiped it off. If it were me, I'd clean it up and monitor it for further seepage. I wouldn't do a thing about it or worry at all if it took another 8000 miles to accumulate that much seepage.

 

[blueridge]

That looks pretty minimal. That might be the sum total of leakage from the day it left the factory floor. You never know if the prior owner ever wiped it off. If it were me, I'd clean it up and monitor it for further seepage. I wouldn't do a thing about it or worry at all if it took another 8000 miles to accumulate that much seepage.

This was about an hour or so after I wiped it clean. I noticed a very small spot of oil on the garage floor on two instances. I originally thought it was coming from the
oil drain plug.

 

[ColoradoRod]

This was about an hour or so after I wiped it clean. I noticed a very small spot of oil on the garage floor on two instances. I originally thought it was coming from the oil drain plug.

Oh bummer. That's a different story.

I haven't looked that closely at mine, but is the notch near the top of the picture where the case halves meet supposed to be there? It almost looks like a hole that might be created if someone were to pry the case halves apart using a flat bladed screwdriver. Kinda the same question re: the chip near the center of your picture where the casting has a cylinder shaped area for a bolt.

These imperfections may be irrelevant depending on the sealing mechanism when the 2 case halves are joined. It's possible that a "mist" of oil could escape these imperfections and cause the leakage. It may be possible to stop the leakage with a little JB Weld. Make sure you clean the area with a solvent--acetone if you've got it, otherwise alcohol would work--and then be very careful not to put so much JB Weld that it would drip down inside the case. It might even be worth letting the JB Weld tack up just a bit before applying it so it wouldn't be so runny. You may even need to apply the JB Weld in stages--building towards the center of the hole from the perimeter like a welder would fill a hole in metal.

This is a little bit of a hack repair, but it'd be a much bigger job to take everything apart and possibly replace the case.

Of course I'm still very new to the NT700 world so I'm sure there's someone out there in forum-land who has much better and more detailed knowledge of what's going on in this pic. For now, I'm doing my part to keep this thread at the top of the "new" section!

 

[blueridge]

Oh bummer. That's a different story.

I haven't looked that closely at mine, but is the notch near the top of the picture where the case halves meet supposed to be there? It almost looks like a hole that might be created if someone were to pry the case halves apart using a flat bladed screwdriver. Kinda the same question re: the chip near the center of your picture where the casting has a cylinder shaped area for a bolt.

These imperfections may be irrelevant depending on the sealing mechanism when the 2 case halves are joined. It's possible that a "mist" of oil could escape these imperfections and cause the leakage. It may be possible to stop the leakage with a little JB Weld. Make sure you clean the area with a solvent--acetone if you've got it, otherwise alcohol would work--and then be very careful not to put so much JB Weld that it would drip down inside the case. It might even be worth letting the JB Weld tack up just a bit before applying it so it wouldn't be so runny. You may even need to apply the JB Weld in stages--building towards the center of the hole from the perimeter like a welder would fill a hole in metal.

This is a little bit of a hack repair, but it'd be a much bigger job to take everything apart and possibly replace the case.

Of course I'm still very new to the NT700 world so I'm sure there's someone out there in forum-land who has much better and more detailed knowledge of what's going on in this pic. For now, I'm doing my part to keep this thread at the top of the "new" section!

The dark patch near the center is not a chip. It looks to be where the gasket material leaked out a bit. The notches at the top of the picture (and at the bottom) appear to be normal. They have the same shape, indicating it was cast that way (maybe to aid in the separation of the crank case). That being said, the top one looks chipped at bit, maybe indicating that someone has worked on it (though hopefully it is an imperfection in the cast). I have the shop manual, but couldn't find any reference to these notches. I did learn that the crank case halves are sealed with Three Bond 1207B liquid gasket.

 

[Hondafan]

Did you recently change the oil and put synthetic in it?

 

[blueridge]

Did you recently change the oil and put synthetic in it?

Synthetic was put in at 5280mi. by last owner. It may be nothing, but both times I've noticed oil, I've had the bike on the center stand.

 

[Hondafan]

Pretty clean oil for 3000+ miles. If it was my bike, I would take the synthetic oil out, and fill it with conventional oil and give it a couple of weeks. I run synthetic and don't have a problem, but synthetic oil by it's nature, flows better than conventional, and will find a weakness to seep through if one exists. Some older engines have no problems with leakage or consumption, but some do. The only other thing that could cause that is a blocked crankcase breather hose. I doubt it is that unless you recently had the airbox off. I would bet it is the oil.

 

[blueridge]

Pretty clean oil for 3000+ miles. If it was my bike, I would take the synthetic oil out, and fill it with conventional oil and give it a couple of weeks. I run synthetic and don't have a problem, but synthetic oil by it's nature, flows better than conventional, and will find a weakness to seep through if one exists. Some older engines have no problems with leakage or consumption, but some do. The only other thing that could cause that is a blocked crankcase breather hose. I doubt it is that unless you recently had the airbox off. I would bet it is the oil.

Thanks, Hondufan! I don't think it's going to be much of an issue, at least for awhile. There's just some wetness at the joint, and no oil on the ground. I think you may be right about the oil. I found an information page put out by Amsoil that pretty much says the same thing. They recommend sticking with synthentic (of course). Their reasoning is that they say say leaks can occur due to cracking and shrinkage of the gasket material caused by sludge buildup in conventional oil blocking lubrication of the gasket. They claim that synthetic oil will correct this underlying situation (sludge buildup) and thereby decrease leak potential. A caveat is that it could take 7000mi. and the situation could worsen some at first. If that is correct, and since the leakage is minimal, I'm leaning to sticking with synthetic on my next oil change and see what happens.

 

[harryhendo]

Hi BlueRidge... I had to respond because I was just up there today on a lovely cool ride! Smoky and cool up there...

Here's a picture of the front of the engine case on my NT, albeit much dirtier than on yours. It looks like that top notch is cast in.



Personally, I would use a torque wrench to make sure that the bolts holding the case halves together are at the right torque value. There might be a tightening sequence in the manual to which you need to adhere. If that doesn't help, I'd then check the manual to see if I could loosen the bolts just to the point of not being tight and then repeat the tightening procedure.

 

[blueridge]

Hi BlueRidge... I had to respond because I was just up there today on a lovely cool ride! Smoky and cool up there...

Here's a picture of the front of the engine case on my NT, albeit much dirtier than on yours. It looks like that top notch is cast in.



Personally, I would use a torque wrench to make sure that the bolts holding the case halves together are at the right torque value. There might be a tightening sequence in the manual to which you need to adhere. If that doesn't help, I'd then check the manual to see if I could loosen the bolts just to the point of not being tight and then repeat the tightening procedure.

I think you may have to tear the engine down to get to all the bolts that hold the halves together. I'm thinking Hondafan had the right idea. I'm going to monitor the situation for now. Really not losing much oil. Are you using synthetic or conventional oil? BTW, it seems we're neighbors. I live in Crozet. Also, do you perform your own maintenance and if so, have you done a valve clearance inspection?

 

[ARKNT]

It is probably worth checking the tightness on the fasteners that are accessible but I would not likely go too deep unless it gets worse.
Has the engine been taken apart? Do the bolts look like it was disassembled? If it was taken apart they may not have applied the 3 bond right or didn't clean it very well first.
It may not turn into a big problem but most all of these engines are quite leak free. Likely will be a bit of a pain for you to keep clean looking.

Brad

 

[Phil Tarman]

I rode my first NT 139,000 miles without ever needing to add any oil.

I hope you get your seepage figured out.

 

[DirtFlier]

A 11-yr old bike with only 7k miles, means it sat a lot and other things could have gone amiss but the crankcase bolts coming loose is not one of those!

Sometimes oil can seep from a location far from where it's first visible.

 

[harryhendo]

Are you using synthetic or conventional oil? Also, do you perform your own maintenance and if so, have you done a valve clearance inspection?

I use Castrol Actevo partial synthetic oil. Case of 6 from Walmart or Amazon can be had for a good price. I perform my own maintenance (there's no bike shop in Charlottesville... I'd have to go to the Waynesboro Honda dealer for maintenance, and they charge unreasonably high prices). I haven't done a valve clearance inspection, but I imagine one of my NTs is due at 31K miles. A good January project...

 

[jhelbling]

I have a friends '10 NT700V with11.7k miles and the same oil seepage at the front of the engine. The NT belonged to her late husband and she knows nothing of the history or maintenance other than he bought the bike new. Unfortunately at this time I have nothing to offer as far as a cause or fix.

 

[blueridge]

I have a friends '10 NT700V with11.7k miles and the same oil seepage at the front of the engine. The NT belonged to her late husband and she knows nothing of the history or maintenance other than he bought the bike new. Unfortunately at this time I have nothing to offer as far as a cause or fix.

I think I found the source of my particular leak. When I did my first valve inspection some 3 months and 2000 miles ago, I noticed that the valve cover gasket on the front cylinder may not have been seated properly. I haven't leaked any oil, since. I'm thinking the problem may have started when the 600 mile service was done.

 

[jhelbling]

I was afraid it was something major, this is encouraging news. I will take a look at the front valve cover. Thanks!

 

[rc_heli_nut]

I think I found the source of my particular leak. When I did my first valve inspection some 3 months and 2000 miles ago, I noticed that the valve cover gasket on the front cylinder may not have been seated properly. I haven't leaked any oil, since. I'm thinking the problem may have started when the 600 mile service was done.

That would do it, the front cover is easy to snag on the exhaust rocker arm adjusters upon removal or install. I rotate the engine until the front exhaust valves are fully open before installing the cover, this gives clearance to reinstall cover without knocking the gasket out of place. Also, I replace the 2 cover grommets as they compress over time, and I put a little Grey sealer in the 2 corners of the valve cover gasket at the half-circle, hope that made sense.

 

[Nick Wilkinson]

Would the oil seep if the sump was overfull?