The dreaded oil leak from oil pan weep hole

2006 FZ1-N...32,000kms.
Oil is leaking from the weep hole...NOT coolant!
R1's seem to be copping the same problem...its growing!
There seems to be a consensus that its happening due to worn or defective drain tube o-rings BUT several members have mentioned the leak persists even after replacing these o-rings.
Does that indicate that the problem may be the oil pump seals?
If so, are these seals internal or are we referring to the o-ring between the strainer and pump body or the 2 o-rings that go either end of the oil feed tube (horse shoe shaped pipe)?
Im hoping to do this myself and i know it can be a PITA but i want to get onto it before the leak gets worse (its only slow-a drip at the moment).
There doesnt seem to be a "go to" thread on this subject...the threads keep ending before a solid or alternative explanation is given.
There are good links that just dont work anymore : ( looks like theres a problem with the FZ1OA site??
Can anyone refer me to a detailed explanation on this subject please, it would be VERY much appreciated....Cheers guys
AFTER RESEARCHING THIS THOROUGHLY, I HAVE ADDED FURTHER INFO IN THE FOLLOWING POSTS.
 
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OK...for anyone that's having this same issue, here's what i've found out.

Oil leaking form the drain pan weep hole is one of two possibilities...

1/.The drain tube o-ring/s are failing OR....

2/.The oil seal on the impeller shaft, sitting between the bearing and the mechanical seal is failing (which means oil/water pump removal and disassembly).

There are approx 7 o-rings in the area above the oil pan, two of which are the drain tube 0-rings.Besides replacing the two drain tube o-rings, the rest are normally ok and dont really suffer any problems BUT while you're in there, you may as well replace them as they are all pretty cheap to buy.

The bearing, oil seal and mechanical seal are a real PITA to remove from the water pump housing and re-fitting the new parts is just as difficult so it may pay to take this particular job to a local bike shop who have a bearing press and the necessary tools to do it properly.
You CAN use the correct size sockets to place over and hammer down the bearing, oil seal and mechanical seal but it is a lot more difficult (but not impossible).

Heating the pump housing will be necessary prior to removing the old bearing and again before dropping the new bearing back in, before seating it with a socket and a hammer (difficult) OR a bearing press (easy).

This is followed by seating the oil seal and mechanical seal (no heat necessary).

There is a bearing in the oil pump housing, that the end of the impeller shaft slides into, that will normally be AOK and wont need replacing.
Re-assembly of the oil/water pump is next (very straight forward) followed by fitment back into the area above the oil pan.
 
To add to the above....
When removing the oil/water pump, the manual states to first remove the whole clutch assembly (PITA) to access the oil/water pump drive chain and cog...(these items are positioned behind the clutch assembly).
THIS IS ACTUALLY UNNECESSARY!!!...thankfully : )
The only reason to do the above is if you are replacing the drive chain and cog, both of which are normally AOK so NO NEED to remove the clutch etc.
INSTEAD...
all you need to do is remove the nut holding the drive cog on the oil/water pump shaft (10mm ring spanner) and the cog and chain seperate from the shaft with ease.
As the bike is standing upright, the drive chain, which is now holding the cog, will simply hang there whilst the pump is removed.
You can lift the cog from the chain and place it to one side if you like (so it doesnt drop off the chain and hit the floor during removal of the pump).....the chain will still hang in position (remember to do these things carefully and take your time).
After re-fitting the oil/water pump, the cog and chain can be re-attached BUT...you wont be able to get a torque wrench in there to tighten the bolt (the one that holds the cog onto the pump drive shaft)....use loctite.
You are going to have to tighten that bolt by hand (again, 10mm ring spanner).
The torque is 10nm so its firm but dont over-tighten (turn bolt in until it bites and then a firm nip up).
Remember, take your time, be careful and there's no reason why you cant get it right the first time : )
 
Hey DaveC,
not a problem mate and thank you.

Here's some EXCELLENT info i just came across regarding seating those bearings, oil seal and mechanical seal in the pump housing.

Its a very simple, old-school method that is really quite ingenious.

Sorry about my crappy diagram...but you get the idea.

Just tighten that nut slowly and in she goes!....(said the nun to the bishop : )

*The washer in front of the bearing obviously needs to be SLIGHTLY smaller in diameter than the bearing so it doesnt hit the sides of the housing as the bearing goes in. The same applies to the oil seal and mechanical seal.
*Make sure there is a washer placed directly behind the bolt head...this will hold the bolt in place and take the pressure as the nut is tightened.

Behold...the old-school bearing press!

simple bearing press.png
 
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PLEASE NOTE - please check the Yamaha OEM parts catalogue to make sure the following part numbers correspond to your model.

.As stated, i own a 2006 FZ1-N but many models are compatible as they have the same part numbers.
Here's a list of the parts needed if pulling down and re-building your oil/water pump.
Most of the O-Rings are usually OK but it's best to replace them while you have the oil pan off as they are pretty cheap and its good, preventative maintainance. With higher milage bikes, its just common sense!

PARTS FOUND UNDER "WATER PUMP".
8/.Bearing - part # 93306-00105-00.
9/.Oil seal - part # 93102-12372-00.
10/.Mechanical seal - part # 11H-12438-10-00.
12/.O-Ring (pump housing) - part # 4XV-12439-00-00.
26/.O-Ring (pump housing to hose) - part # 93210-357A2-00.
28/.O-Ring (drain tube) YOU NEED 2 OF THESE - part # 93210-06667-00.
30/.O-Ring (pipe to pump) - part # 93210-235A1-00.
31/.O-Ring (pipe to pump) - part # 93210-27778-00.
39/.O-Ring (pump housing to hose) - part # 93210-235A1-00.

PARTS FOUND UNDER "OIL PUMP".
3/.0-Ring (strainer) - part # 93210-22298-00
8/.O-Ring (oil pipe) YOU NEED 2 OF THESE - part # 93210-14003-00.

PARTS FOUND UNDER "OIL CLEANER".
4/.O-Ring (oil relief valve) - part # 93210-15566-00.
7/.Gasket (drain plug) - part # 214-11198-01-00.
9/.Gasket (oil pan) - part # 99999-03623-00.
16/.Gasket (oil cooler bolt gasket) - part # 5EB-13475-00-00.
17/.O-Ring (oil cooler) - part # 5JW-13473-00-00.

PARTS FOUND UNDER "EXHAUST".
3/.Gaskets (for headers) YOU WILL NEED 4 OF THESE - part # 4FM-14613-00-00.

Up to this point, the parts come to a total of approximately US $150-160 (based on Partzilla's pricing).

There is also an O-Ring on the Oil level gauge Switch which is bolted to the bottom of the oil pan, next to the drain plug. This O-Ring can not be ordered as a separate part, you have to order the whole oil level gauge switch.
FOUND IN "ELECTRICAL 1" (14/.Oil level gauge assembly or switch - part # 5VY-85720-00-00)...another US $40-50 to the total.

The oil level gauge switch O-Ring does tend to weep a little bit on higher milage bikes...Its more of a staining around the switch than anything else.
PLEASE NOTE - replacement of the oil level gauge switch DOESNT have to be done whilst the oil pan is removed as It can be accessed at any time without having to take the exhaust off etc.
You will have to drain the engine oil prior to removal though.

Other items would include copper grease for the header/exhaust bolts and gaskets.
Loctite blue 243-medium strength threadlocker.
Oil resistant silicone for the ends of the drain tube (use sparingly).
Coolant.
Engine oil and filter.
If i think of anything else, i'll add it to the list.

There you go people, it takes the guess work out of it for you and its a reference if need be....Enjoy!
 
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By way of introduction... I am in the middle of this job on my 2001 FZ1. I have most of it back together, but I cannot remember how the last two O rings fit between the water pump and the coolant pipe going through the front of the crankcase. The shop manual shows then in sequence, but this seems odd. How are these supposed to be used?
 

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Hi Luckyduc,
not a problem...very glad i can help.
Number 30 goes where the red/orange 0-ring is in your photo and 29 stays where it is (between water pump and coolant pipe).
Wish you the best of success with the entire job - cheers.
 
Hi Luckyduc,
not a problem...very glad i can help.
Number 30 goes where the red/orange 0-ring is in your photo and 29 stays where it is (between water pump and coolant pipe).
Wish you the best of success with the entire job - cheers.
Thanks for the rapid response. I thought the oil seals were all that orange colour, viton or similar. Did the spec change at some point?
 
Not a problem Lukyduc.
Good question...Im not really sure why Yamaha chose to change certain o-rings.
Would be worth looking into just to see what the reasoning was behind the decision.
 
Thanks for the rapid response. I thought the oil seals were all that orange colour, viton or similar. Did the spec change at some point?
Hi Luckyduc, how did it finish up? Did this thread of maintenance fix your oil leak? I just discovered the dreaded oil pan leak on my 2006 FZ1 (38000 kms). Cheers
 
Hi Luckyduc, how did it finish up? Did this thread of maintenance fix your oil leak? I just discovered the dreaded oil pan leak on my 2006 FZ1 (38000 kms). Cheers


So to be clear, I had coolant leaking from the drain pipe in the middle of the pan. Some bikes leak oil...

Just got everything back together a few days ago, and so far, looks like I didn't break anything. I did have a leak in the hose from the radiator to the overflow tank that had me worried, but fixed that last night and all seems well again. I had a few issues along the way but nothing too daunting. Mostly me being uncertain about what comes next in the process and remembering the order for reassembly. I have attached a few of pages from the manual which helped me a lot.

I couldn't get the drain pipe to come loose from the sump pan to replace O ring, part no. 25, so I just replace the one at the top. I hope that doesn't come back to bite me, but if it does, all I have to do is drop the pan and make a bigger effort to remove the pipe.

Shout if you need guidance on anything. Doing this once doth not an expert make, but in the land of the blind a man with one eye is king! :)

Jim M.
 

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So to be clear, I had coolant leaking from the drain pipe in the middle of the pan. Some bikes leak oil...

Just got everything back together a few days ago, and so far, looks like I didn't break anything. I did have a leak in the hose from the radiator to the overflow tank that had me worried, but fixed that last night and all seems well again. I had a few issues along the way but nothing too daunting. Mostly me being uncertain about what comes next in the process and remembering the order for reassembly. I have attached a few of pages from the manual which helped me a lot.

I couldn't get the drain pipe to come loose from the sump pan to replace O ring, part no. 25, so I just replace the one at the top. I hope that doesn't come back to bite me, but if it does, all I have to do is drop the pan and make a bigger effort to remove the pipe.

Shout if you need guidance on anything. Doing this once doth not an expert make, but in the land of the blind a man with one eye is king! :)

Jim M.
Thanks Lukyduc. This should help a lot! You have P/N: 5 (Impeller Shaft) circled in red. Did you replace this aswell?
 
Thanks Lukyduc. This should help a lot! You have P/N: 5 (Impeller Shaft) circled in red. Did you replace this aswell?
I didn't, just cleaned it up with some emery cloth. I showed it to a local bike mechanic and he didn't think it needed replacement.

HOWEVER... I may have spoken too soon. It looks like I have coolant in the oil. Damn it. I think that must be a bad installation of one of the coolant pipe O rings. My mechanic mate warned me that they can get "hare lipped" and leak. I made a rookie mistake and put the sump on before inserting the lower coolant pipe at the front of the engine so inserted it blind, by feel. I suspect that one went wrong.

So now I get to strip it down again to take the sump off to see if the leak is obvious. Feck it!
 
Lukyduc...that coolant pipe doesnt slide in as youd expect.
The end of the pipe needs to be lifted very slightly as it is inserted in the water pump outlet...at least mine did!
It is necessary to apply standard grease to BOTH o-rings prior to installation.It helps to stop the o-ring/s from getting pinched when inserting the water pipe and helps them to seat better too.
I hope you have success.
 
Lukyduc...that coolant pipe doesnt slide in as youd expect.
The end of the pipe needs to be lifted very slightly as it is inserted in the water pump outlet...at least mine did!
It is necessary to apply standard grease to BOTH o-rings prior to installation.It helps to stop the o-ring/s from getting pinched when inserting the water pipe and helps them to seat better too.
I hope you have success.
This is turning into a marathon! I dropped the sump, refilled the cooling system, pressurized the cooling system to 15lbs, and saw no leaks, even overnight.

It is a distinct possibility that I overfilled the sump. I still had the centrestand on a wooden block so maybe that was not the best way to check the level.

So put it all back together, no obvious leaks at idle, and left the bike on the sidestand for two weeks. Came back to a small puddle of nice clean oil about 8" by 4" on the floor. Feck it!
 
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Are you able to follow the oil leak back to it's source Lukyduc?
Being new oil,it will be harder to see an obvious "leak trail" but if you use a good light it should make it easier to spot.
It will probably be one of several possibilities:-
The o-ring on your oil level switch isnt sealing properly.
Your oil pan gasket is leaking somewhere.
The front o-ring on the L-Shaped coolant pipe isnt sealing properly (my new o-ring seemed to be too tight so i re-used the old,orange one with no dramas).
The larger o-ring that sits within a designated slot in the engine case,on the coolant inlet side (the one that seals the water pump inlet housing when it is repositioned through the engine case.
If you removed your oil cooler,it could be the o-ring that goes between it and the engine case...or possibly the sealing washer on the bolt.
The best plan of attack would be to try and trace the leak back to its source.
Hang in there, it may not end up being as big a problem as you think.
 
Found it... I think. This was after spraying talc and waiting an hour or so. The bottom of the coolant pipe is damp with oil. It is a very slow leak! Freaking annoying 20210925_185932~2.jpg
 
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