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BF90 water leaking out of two holes in oil pan where drive shaft is.

K

k_emarine

Member
Hi I have two fuel injected honda BF90s. They recently started leaking water out of the side covers. I took the covers off and found that it is coming out of two holes in the oil pan where the drive shaft goes up through to the powerhead. I replaced the water pumps and also the grommets that are in the 5inch spacer that goes on top of the gearcase. It is still leaking a lot of water. I noticed that if I take both thermostats out it will barely dribble out if not stop completely. Any input would be greatly appreciated. Thanks!
 
I am assuming this is not normal since those side covers have a rubber gasket to keep water out it would be kinda silly to dump the water inside the cowlings. Nobody has any input?
 
Not sure but it sounds as if you could have some upper water tube grommets (#5 in the link below) leaking. The fact that the leak slows dramatically when the stats are out might make sense because that would allow for much less restriction to the flow coming from the pump and back out to intake and exhaust. That would tend to "depressurize" the water tube and cause there to be less water coming out from under the case.

http://www.boats.net/parts/search/H...07 and Later/BF90DK0 LRTA/OIL CASE/parts.html

The grommets I am referring to are at the top of the water tube (item #8 ) depicted in the link below and labeled E6 indicating the page they are located on.

http://www.boats.net/parts/search/H...DK0 LRTA/WATER PUMP VERTICAL SHAFT/parts.html

Just a guess/theory.
 
One note I can make is that when you start the engine and then acclerate it to the point where the water will start coming out you can go back and watch it and it appears to work its way from the bottom up. In other words there are two holes and it gradually starts dribbling out of the bottom hole until it starts pouring out of it and then gradually starts dribbling out of the top hole until it starts pouring out of both.
 
You have to go into advance mode then click on the paper clip for attachments. Then you download the picture.....then you select it to insert it.

I think you have to go to preview to see that it made it in the post.

Try loading in a picture again.

I do not have a clue where the water it coming out.

Mike
 
pictures will still not upload in advanced exactly how you said. It goes up to 100% and then goes blank. I really need these motor resolved....:confused:
 
Do you have Google Drive, Drop box or a Snap Fish account. You can upload pictures and share the link with anyone that you want. Google Drive and Snap Fish are free. You have to have a gmail address to use Google Drive.

Upload the photos to one of these and then post the link.

Others may have an easier way to share....if so, I hope they jump in. These are the first that come to mind.

Mike
 
Well, that was an exercise in futility! I "signed in" to see your pictures and I got a message that I would need "permission". So, I asked for "permission" and got a message that I would just have to sit and wait. YEAH! RIGHT! Google got me again!
 
I don't blame you. It's the whole tech-block thing that gets me goin'. You wouldn't have even gone there if you had been able to post pics here. You're not the first to have trouble with that either.

I'm just interested in your problem. I don't have any info for you. I'm a small outboard guy. Hopefully Mike will have something for you soon. Hang in there.
 
Look how much you are learning already!!!

If you are referring to the two holes (one over the other), they are relief holes to minimize pressure on the shift shaft seal from water going up the tube as the boat moves forward.

I would not think a lot of water should come out unless the motor is rigged too low and trimmed way down causing extra water pressure.

Mike
 
The water is shooting out of those two holes probably 6-8 inches (both of them) and I am on dry land with this happening don't have to be moving at all. I have the motors dropped down in a barrel, start them up and rev up to about 3000 rpms and they just start gushing out of those two holes. If the side covers are on it just starts pouring out anywhere it can.
 
I am still not sure anything is wrong. Does it do this when you run the engines on a hose with rabbit ears or when you are in the open water?

If not it might just be the turbulence of the exhaust etc in the enclosed area of a barrel that is forcing water up the tube? Although, I can not explain the minimized flow when the thermostats are pulled out.

The tube that the holes are in is isolated from the rest of the midsection except at the gearcase (where the shift shaft connects to the gearcase) and an opening to the outside just above the lower motor mounts. At least it should be.....maybe a hole has developed somewhere along the tube.

If you still see water shooting out when on a hose, then it may be time to start exploring.

Removing the gearcase...then the midsection and examine the tube as well as the grommets that Jimmy has referred to.

Mike
 
Just started on hose with ear muffs and no water at all came out. The thermostats are still out of the engine so I will put them back in in the morning just to make sure. I do not think there is a problem with the water tube or the grommets because when I have the gearcase off I put a hose directly on the water tube and turned it on and no water comes out of the holes. The only time it seems to come out at this point is when we have it in our drum (which is actually some sort of cattle trough.) Have not had the boat in the water but it was pulled out for this reason.
 
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