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Honda BF150 Leaking oil

I re-powered my boat this past winter with a 2006 Honda BF150. The engine has 100 hours on it of which i have put 60 hrs this summer. Last week the engine started leaking a little bit of oil when i trim it up. I would say it leaked about 2-3 ounces after running it for 2-3 hours? I have taken the side covers off and I can't find where it's leaking.

Any ideas?
 
Where are you seeing oil? Up top around the engine? Or in the water?

If just in the water, you could have a leak in the lower unit or the power tilt and trim unit.

Mike
 
It collects up top under the engine cover near the front. Then when I lift the engine up it runs out in the boat, out the scuppers in the water. It is motor oil, not lower unit oil or ptt oil.

I pulled the starter and looked down in there. There is some rust and a hint of oil. Also, I pulled the air box and there is also a small coating of oil in there.

Next I am going to try to run the engine with all over covers off to see if I can see where it is coming from.

Thanks in advance for your help...
 
I would look closed around the edges of the top and front cover of the engine. If anyone has ever had it apart, they may not have resealed the top or front on correctly and it may be leaking.

If you see no visible signs on the exterior, pull your starter again and see if there is any additional oil. That area should have very little if, any oil in it. Rust is also not a good sign. If your crank is rusting, it can cause the seal to leak. Also, # 3 and 33 is this picture are just steel and can rust and leak if water got into that area.. http://www.boats.net/parts/search/Honda/Outboard%20Engine/2006/BF135A6%20XA%20VIN%23%20BARJ-1200001%20TO%20BARJ-1299999/CYLINDER%20BLOCK/parts.html

Mike
 
I started the engine and then pulled the starter. Bad news... Oil was flinging all around. :(What caused these seals to fail? I don't feel comfortable tearing into this so off to the dealer.
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Since you may not know the complete history of this motor, it could be any number of things. The first thing that probably happened is that water got into the flywheel area. It could come from the engine being submerged; engine mounted too low and water is forced through the shift shaft seal;who knows what else.

Unfortunately, the only way the dealer is going to be able to tell where it is leaking for sure is to pull the powerhead and inspect.

Sorry for the bad news.

Mike
 
Yes, history.. well it's history.. Who knows... Came from a Honda dealer that said customer was "upsizing". I rigged this boat and I don't think the engine is too low? The anti-vent plate is about 1" above the bottom of the boat. Does that sounds right? I can take a picture if it would help. I want to make sure this doesn't happen again.

Thanks again for your thoughts...

Graham
 
The distance at the bottom seems ok, depending on your boat. You also have to be sure that the bottom of the exhaust relief holes up on the back of the engine are at least 5.9 inches (150mm) from the water line.

The problem probably started with the previous owner. It is most likely nothing that you did.

Mie
 
Yes, the upper exhaust port is no where near the water line. I'm dropping it off at the dealer early next week.. Well see what they say..

I'll report back.

Thanks again..
 
**UPDATE**

I finally got the boat to my local Honda dealer. They called today to ask a couple questions trying to figure out where the oil was coming from.

I told the tech I had done a little investigation myself and found oil in the flywheel area. He said that was normal to have a little oil in there. He seemed like he knew his stuff???

I'm not sure what to think. I was under the impression there should not be any oil in there.
 
Reedville - Keep us posted on this. I have high interest. Last time I looked at the flywheel on my 225, there was no oil, and that's after almost 1100 hours.

BTW - I'm right up river from you on the Potomac, across from the fuel tanks. Would appreciate you letting me know when the rock show up down your way. I can get to the Smith Point Light in about 40 minutes.
 
I just heard back from the dealer. $2700 to pull the powerhead and replace all the seals. The tech didn't seem very convincing either. Apparently he talked to Honda and they told him there should not be any oil in the flywheel/starter area.

Looks like I found me a winter project...

I am going to build me a engine stand and do it myself. With a little help from marineengine.com of course. ;)

I'll be sure the update the thread with progress, pictures, and questions!
 
Reedville - Sure am sorry 'bout that. I always look at those situations as a learning experience. You'll certainly get to know that engine.
 
Reedville - Sure am sorry 'bout that. I always look at those situations as a learning experience. You'll certainly get to know that engine.

I'm just thinkfull it's not the middle of the summer. That would have been a bum deal.

Plus I can use my Dads boat for a little fall rock fishing. Let him pay for the gas. Lol.
 
I am glad that the dealer got the straight story on no oil in that area. Unfortunately, removing the powerhead is the only way to fix it.

When you take it apart, be sure to follow the official Honda manual from helminc.com. Take your time and take a lot of pictures so you get the hoses etc put back into the right place and routed the correct way.

Also, be very careful in keeping the teeth of shift linkage under the powerhead aligned correctly. Although, it you get everything back on and it is out of alignment, the manual has a way to correct it without taking the powerhead back off.

Just a quick look at the seals that will be needed...they will be in the neighbor of $400 - $500. I am sure you will do a careful exam of the bottom of the block to check for any bad seals or core plugs. Also check the crank seal very carefully. I think you can change it without disassembling the engine...although I have not tried it myself yet.

When you make your stand, make sure there will be room to tilt the motor up for you can take off the lower unit and some of the lower parts of the engine. It is much easier on the back that way.\

Mike
 
I am glad that the dealer got the straight story on no oil in that area. Unfortunately, removing the powerhead is the only way to fix it.

When you take it apart, be sure to follow the official Honda manual from helminc.com. Take your time and take a lot of pictures so you get the hoses etc put back into the right place and routed the correct way.

Also, be very careful in keeping the teeth of shift linkage under the powerhead aligned correctly. Although, it you get everything back on and it is out of alignment, the manual has a way to correct it without taking the powerhead back off.

Just a quick look at the seals that will be needed...they will be in the neighbor of $400 - $500. I am sure you will do a careful exam of the bottom of the block to check for any bad seals or core plugs. Also check the crank seal very carefully. I think you can change it without disassembling the engine...although I have not tried it myself yet.

When you make your stand, make sure there will be room to tilt the motor up for you can take off the lower unit and some of the lower parts of the engine. It is much easier on the back that way.\

Mike

Thanks Mike.. I do have the factory Honda repair manual which will be very helpful.
 
Well...Sometime has passed.. The engine is off and all apart in my garage. So far so good.. Putting it back together might be another story.

It appears some salt water got into the flywheel area and corroded it up pretty good(previous owner partially submerged engine). I'm not 100% sure the oil leak is from the main crankshaft seal or not. It is hard to tell. I have ordered all the seals just to be sure. Hopefully this will fix my problem. I wish there was a way to tell exactly where it is leaking???

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I forgot to mention...be sure to check sealing bolt and washer #3 and #33. http://www.boats.net/parts/search/H...001 TO BANJ-1299999/CYLINDER BLOCK/parts.html

If it gets wet, it will rust and will leak oil. If it even looks suspicious, change it out and put some sealant on it when you put it back in. I do not think the book addresses this.

Mike


The sealing bolt, just to the lower left of the crankshaft, definitely should be changed.

Do not forget to change the seals in the lower motor case to keep any further water out of that area.

Mike
 
I got my motor all back together and bolted back on my boat this weekend. It went back together with no problems! I ran it on the water hose for awhile and everything looks good so far! I'll water test it soon.
 
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