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Transmission Gasket

7K views 60 replies 11 participants last post by  plitskin5 
#1 ·
Ok. So i am crossing items of the list of things wrong before the yard sale bike is back on the rode. Went to fill to motor up with new oil (after draining off the old oil in there) and immediately i have a fast drip from the seal between the engine and transmission. Looks like i may have to change it. So my questions are



1. Where can i find this gasket?

2. Does the motor have to come out to change this? or can i remove the rear tire and drive shaft, unbolt the transmission from the engine and frame and walk it back just far enough to R&R the seal?
 
#2 ·
If the leak is at the rear of the engine, from the drive shaft, or any other part of the rear engine casing, then yes, it is an engine drop situation. Check the Quick Reference section of General Discussion for lots of helpful info.

*edit* Gasket is readily available at many online places, but this forum highly, and STRONGLY, recommends an OEM Honda gasket for the rear casing.



Joel in the Couve
 
#3 ·
Transmission gaskets or front cover gaskets are available to order from honda dealers or places online that sell honda parts.



That is also one of the gaskets that isn't the biggest deal in clearance so you can even make your own if you get some 1/32 or maybe it was 1/16 gasket paper that is gas and oil resistant. I bought enough to make that part twice for $3. Then just trace the front cover on to it and cut out the holes and inside.



The engine doesn't need to be dropped but you have to pull the radiator, front engine mount and fan off.
 
#4 ·
Reading it again I see the first post is a bit confused. He's probably thinking of this like a car.



The transmission is in the engine. Part of the block. There is a front cover and a rear cover. If it's leaking in the rear then the engine needs to be dropped.



Also where is the dripping? Is it on the left side by the shifter lever. If so that seal only costs $5 to fix and can be done with the engine in.
 
#50 ·
blindstitch,

Hello, In the front of the engine with cover off, over the transmission there is a hole that looks like where a shaft

should be, with 2 small threaded holes above it. I see it in your picture and I seen them on my engine today.

Did some of these engines have a balancer or a damper. Thanks OLDBIE
 
#6 ·
Wow great pictures thanks! Its on the rear of the engine (towards rear tire) and coming out of the riders right hand side. It looks like its leaking right where the cover meets the engine. So if thats the case engine has to come out eh?
 
#9 ·
unless you just want to,or have more reasons to take the engine out.i would say.....dont do it.


last winter i pulled my engine to replace the camchain etc.6 months prior i had a rear case leak.i was not going to pull my engine 6 months prior just for that.

PATTEX,,or something similar will repir it.its a 2 part mix.exactly the same colour as the engine,water,oil and petrol proof.[if you go in this direction,ill walk you through it.

http://www.pattex.es/productos/producto.asp?id=67

is the one i use.you must have suitable products over there.

my 10c worth
 
#10 ·
Bandit makes a good point, if it is a small leak. I have also used JB Weld on a minor leak at the rear case that has lasted years now. As stated, if all other matters are okay, you could get by that way. If the OP gave us more details about the bike it would really help. Like mileage of the bike etc.
 
#11 ·
#12 ·
I guess the question is where is it really.

David suggested something like cleaning the area completely and throwing flour or a similar powder on the engine and run the engine till the leak starts. Then you should have it pinpointed pretty good.
 
#21 ·
Don has it almost right ... and I have never seen it fail.



You put the flour on your hand and blow it on the engine after it has run a few minutes. The darker the flour the closer you are to the leak.



You have to start with a perfectly clean engine though.
 
#13 ·
I will do that.. So far with a clean underside of the area (Seam between the back cover and motor) if i pour oil into the engine, i get a drip. Enough of a drip that it requires a catch pan and it will be almost out of oil in 24 hours.
 
#14 ·
whooooo.that is new information.forget all the above posts,well mine anyway.to loose all your oil in 24 hours is not a drip.
its a hole
 
#17 ·
Well it sounds like a trip to the Honda dealer is in my future. I have the original tech manual which details the engine removal. Seems pretty straight forward. I may use some jack stands and a floor jack to make life simpler. Unless these is a better way? :)
 
#18 ·
While i have the motor out (keeping in mind it has 31,000 is VERY clean on the outside as well as under the valve covers) what else should i replace? Nothing since it works or would things like a water pump ect be worth while since i will already be back there?
 
#22 ·
That mileage would be about halfway to 3/4 way to needing the cam chain work. You should also consider the water pump mechanical seal, but if there was no sign of anything from the weep hole in the rear case before, you may be alright. You might also focus on the output shaft from the tranny that is at the bottom right of the pic Stitch put up for the rear case. Make sure you pay attention to some of the other posts here about reinstalling the rear cover, because there are tricks to the shifter lever, and the starter motor.



I've not heard too many horror stories about the output shaft so far, so that shouldn't be much concern, all things being equal.
 
#24 ·
for me,

the mileage,the weather,and if its a daily runner.

specs of ali. in your oil[screen when you change it]

the previous history of the bike.whether the cam chain has been regularly adjusted.

then the dreaded cam chain rattle


for me,all of the above played a part
 
#25 ·
well it sounds like i might have to trial and error it. The bike ran. So as soon as i get the carbs back it will run for a longer period of time. Now in that short period of time i heard no rattle so fingers crossed and lets see if she will be ok for a few thousand. Or tell the next service.
 
#26 ·
Question for everyone. Its going back together today and the shaft that the shifter bolts to has come out. Easily goes back in but in what position do the teeth line up. I don't want to get this back together and not be able to get it into all gears. Does anyone have a picture of this?
 
#29 ·
Did you try spinning the output shaft a bit. Is the engine still disassembled or did you put the rear cover back on? If the cover is on maybe the gearshift is on the wrong spline.
 
#30 ·
i need to spin the output shaft you are correct. I still have the back cover off. I was hoping maybe someone had some pictures of the teeth messhed in first so i can make sure i am right. I think there is some pictures of just that on this forum already. Well see what happens, back to the garage.
 
#33 ·
once you have your cover on....prior to fitting the engine back into the bike...put your gear selector on.spinning the shaft,make sure you can get all your gears
 
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