1994 Vulcan 1500 oil consumption???

[jmk865]

I have a '94 Vulcan 1500 with a Tow-Pac. It has 23,000 miles on and had 19,000 when I got it 11 months ago. No problems with it except a mysterious loss of approx 1 quart of oil a few days ago. No leaks, no blue smoke, just noticed the oil light began to flicker very dimly when making a fairly hard stop. Immediately stopped, let it sit for a bit and checked oil level to find it down a quart, Red light did not come on while going down the road; only when stopping quickly. Topped it off and no problems since. Any ideas?

[Sinical]

I'm not familiar with the Vulcan 1500, but am aware that more than a few Japanese bikes have an EPA system that also includes the crankcase vent oftentimes being routed into the air box (s ?)

This design can commonly allow oil to enter the air boxes and from there, the oil could potentially enter the carbs, which is obviously not cool and one reason that I'm not a huge fan of this inherent design.

Since you're not seeing smoke from the exhaust, then you're probably not getting any oil coming thru the carbs, but you should definitely check the air boxes for peace of mind to insure that your "lost" oil isn't sitting in the air box and contaminating the air filters.

You might also have some drain tubes coming down from each air box (unknown to me since I've never owned a Vulcan) or a drain tube coming down from a separator box. Any drain tube should have a plug on the end. You can remove the plug(s) and let 'em drain and this is a maintenance gig that should be periodically done anyways.

Good luck!

[jmk865]

I will check it out and thanks for the help.

[Rmitchell55]

JMK 865

Many of the early Vulcan 1500's had problems with oil consumption. Most of the problems was traced to the pistons having short skirts (bottom of the piston). This allowed the piston to rock slightly which wore the cylinder making it slightly oval. This allowed the oil/vapor to be sucked past the piston rings into the cylinders. There was a FAR (factory authorized repair) to bore out the cylinders oversize and replace the piston with a later model which had a longer skirt. The issue with the oil light flickering is on a hard stop the oil runs to the front of the engine away from the oil pump pickup.

For any thing you want to know about a Vulcan go here: www.vroc.org l

[jmk865]

Thanks, I'll check the site out

[John Luciano]

Just cuz there is no smoke don't mean you ain't burning oil. Just cuz there is no oil on the ground don't mean it ain't leaking. U could be only leaking under a load. Old trick in the used car biz BITD when oil burning cars with 40,000 on them were common. u would put Mobile one in the car and it does not smoke blue. My bet is most synthetic oil will not show smoke. Also if the bike is leaking and dripping on a hot surface it will never touch the ground.
Oil is going some place.

[Sinical]

Great info, Rmitchell55

JMK......I took a quick look, typed in "oil consumption FAR" in the Archive/Search function and found this:

http://www.vroc.org/archive.html

No small factory flaw to say the least. Makes the chintzey OEM Suzuki clutch spring failures at 15,000 miles or less pale by comparison.

Good luck and Ride Safe......

Edit: Link didn't show the posts I was reading. Just click on link and type in "oil consumption FAR" on the Search line of that page.

[jmk865]

After "losing" that quart of oil; I changed the oil and filter and had the mechanic give it a look-over. He found nothing wromg. Since the oil change I have ridden 500 miles or so and the oil level has not gone down. To be honest I stretched that oil change a little longer than I should have and am wondering if the filter or screen had gotten plugged up a little and forced the engine to burn a little oil and maybe that caused the useage. I am by no means a mechanic ; so am just guessing, I did purchase a mechanics mirror so I can see the oil sight glass much easier now.

[Sinical]

It's certainly possible that you were only dealing with a situation of the oil level running low due to a longer interval between oil changes and/or not checking the oil level frequently enough. It happens.

You've also got the helpful info provided from "Rmitchell55" about the oil consumption and Factory Authorized Repair to keep in mind in case it appears to be losing oil quicker than expected.

Good on ya for getting the mirror to keep an eye on the sight glass more often. Pre-ride checks and regular routine maintenance would include checking the oil level as well as doing oil changes at the proper intervals, many go by the "every 3 months or every 3,000 miles" rule for oil changes.

Other than keeping an eye on it, one thing you might do (or your mechanic might have already done) is to check the spark plugs to see if there's any sign of oil residue.

Enjoy and Ride Safe......

[jmk865]

Thanks for all the help and suggestions guys. I've gotten a lot of great advice and tips since joining this forum. I appreciate each and every bit of it.

[jmk865]

I've been monitoring my oil consumption very closely now and it appears I am using a little less than a quart in 1900 miles. That really doesn't seem to be a lot for a 20 year old trike. I will , however, continue to watch closely and see if it continues that pattern or gets worse. Since I do not take trips or other very long rides, this may be just a matter of keeping an eye on it.

[wiredgeorge]

I am familiar with the VN1500A. The pistons were drilled for piston pins slightly off from where they should have been. This causes the pistons to rock and prematurely causes the cylinder bores to oval. This allows blow-by and high oil consumption. Kawasaki never officially took steps to rectify but if the bike had over a certain amount of consumption (it was a lot) during warranty they would fix the problem.

The best way to fix the problem is to buy a set of VN1500 pistons in one of the oversize sizes, remove the cylinder heads and take the new pistons/rings to a MOTORCYCLE machine shop and have them bore and hone and fit the pistons. Unfortunately, the engine has to come out of the frame to do this as there is not enough clearance to get the valve covers off much less anything below the valve covers.

I installed Wiseco pistons when I fixed mine a few years ago and it was mistake. They were not well made and the lan between rings broke and I lost compression in that cylinder and ended up fixing with Nomad pistons as should have been done in the first place. As has been pointed out, the oil consumption issue was very well known and a hot topic 12-15 years ago on the VROC forum. I am VROC 2420 btw...