I noticed a few drops of oil under my ST. Is this the mechanical seal leak?
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Oil Leak behind the waterpump
- Thread starter catneck
- Start date
Thanks, that's a great help!
Kevcules
Site Supporter
I just went through a bit of the same problem. I removed and replaced my valve covers after a valve adjustment and after the first start and warm up run, I had oil dripping on the ground.
After checking where it came from, it was indeed the square hole like yours. I diagnosed the problem as I went back and looked at the top part of the valve cover on the left side as the engine ran. I could clearly see the oil spitting out. I must have somehow not positioned the gasket properly. I removed that valve cover, then gasket and cleaned everything up and re-installed. No more leaks.
To my surprise, I had a small amount of oil leaking from that square hole for another week? I only started the bike and warmed it up in my garage without riding it and couldn't believe the amount of oil that kept draining out. Finally after there was very little oily residue at the square hole, I went for a ride. To my surprise, I noticed more oil dripping below my bike in my garage after the ride. Off came the freaking fairings again and the oil was coming from the square hole again!!
I couldn't find any more leaks and realized that all the swirling air flow from riding the bike must have helped the rest of the remaining oil drain out the square hole that had leaked on the top part of the engine V.
After this long winded response,
if you have a leak up there somewhere, the square hole is where it will come out for days. Good luck...
After checking where it came from, it was indeed the square hole like yours. I diagnosed the problem as I went back and looked at the top part of the valve cover on the left side as the engine ran. I could clearly see the oil spitting out. I must have somehow not positioned the gasket properly. I removed that valve cover, then gasket and cleaned everything up and re-installed. No more leaks.
To my surprise, I had a small amount of oil leaking from that square hole for another week? I only started the bike and warmed it up in my garage without riding it and couldn't believe the amount of oil that kept draining out. Finally after there was very little oily residue at the square hole, I went for a ride. To my surprise, I noticed more oil dripping below my bike in my garage after the ride. Off came the freaking fairings again and the oil was coming from the square hole again!!
I couldn't find any more leaks and realized that all the swirling air flow from riding the bike must have helped the rest of the remaining oil drain out the square hole that had leaked on the top part of the engine V.
After this long winded response,
if you have a leak up there somewhere, the square hole is where it will come out for days. Good luck...
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Thanks for the instant assist.
Odd that I have not done any engine work other than oil change in my brief ownership.
AHA. Possibly there was a spill when I filled the oil.
It has been 100% leak free in the few hundred miles since, but, the dribble is very clean.
It of course leaked on my perspective buyer's test ride.
I will pull off the Tupperware and find the source of the dribble and clean 'er out.
Again, thanks.
Odd that I have not done any engine work other than oil change in my brief ownership.
AHA. Possibly there was a spill when I filled the oil.
It has been 100% leak free in the few hundred miles since, but, the dribble is very clean.
It of course leaked on my perspective buyer's test ride.
I will pull off the Tupperware and find the source of the dribble and clean 'er out.
Again, thanks.
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If you are saying you will find the source of the leak and stop it, that is one thing. If you are going to go into the Vee of the engine, that is another. To get there in order to clean up any residual oil, you will have to pull the tank, the airbox, and the throttle bodies. Getting to the top of the engine is a major task.
Or, you could simply remove the radiator from the front (and replace the T-stat and O-ring while your in there) do a coolant flush, gently snug and tighten all the loose coolant hoses that your going to find, and pour a cup of simple green, or your favorite degreaser into a long funnel (or a short funnel with a piece of clear tubing attached) and pour a gallon of hot water into the V and watch it come pouring out the square hole until its clean. That's if you wanted to. No need what so ever to remove the air box, or throttle bodies .
However, the first things I would check would be simple (free) stuff first....like, is the O-ring still on the Oil filer cap? They tend to tall off without people noticing them.
When you did the oil change, did you over fill the oil level? Is the oil coming our your crankcase breather hose (into the airbox, and then draining into the V?)
Remove the plastic, then pull off both the cylinder head cover pieces (grey plastic) then remove the bolts holding the coils to the frame, you can now look straight down behind the cylinders to see if any of the rubber skirt is pinched, causing your leak(s)?
Standing by the White Courtesy Phone if needed.
.However, the first things I would check would be simple (free) stuff first....like, is the O-ring still on the Oil filer cap? They tend to tall off without people noticing them.
When you did the oil change, did you over fill the oil level? Is the oil coming our your crankcase breather hose (into the airbox, and then draining into the V?)
Remove the plastic, then pull off both the cylinder head cover pieces (grey plastic) then remove the bolts holding the coils to the frame, you can now look straight down behind the cylinders to see if any of the rubber skirt is pinched, causing your leak(s)?
Standing by the White Courtesy Phone if needed.
I am busy the next few days, will follow this advice and post findings. Thanks!
It was a loose valve cover, fixed. The drip has stopped. Thanks for the help.
Sadlsor
Site Supporter
- Joined
- Jan 15, 2020
- Messages
- 4,286
- Age
- 66
- Location
- Birmingham, Alabama
- Bike
- 2008 ST1300A
- STOC #
- 9065
Thanks for the update!
It's perplexing when someone posts for assistance, we have an ongoing thread for weeks, and the OP just goes dark...
I'm not talking about the CT, either.
It's perplexing when someone posts for assistance, we have an ongoing thread for weeks, and the OP just goes dark...
I'm not talking about the CT, either.