Leaks - Two Questions [Archive]

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BubbaZanetti

04-20-2009, 09:56 AM

1. Pushrod tube seals - a question on replacement. The snowbum tech article i read concerning this procedure highly recommends NOT removing pistons from the barrels, which i'd rather not do anyway, but i'm assuming you have to disconnect the piston from the con rod to put the big O rings on the base of the cylinder barrel? Please let me know what the BEST way to do this is, being in NYC, i don't want to have to do it twice, wrenching here is hard.:laugh

2. I'm leaking a healthy amount of gearbox oil, not a Norton amount of oil, but a drop or two every few days, underside of the tranny is all wet as is the top of the block below it. I'm not certain yet, but i THINK that the leak is coming from the neutral indicator switch because that connector is soaked and i'm not experiencing any clutch slippage, so i don't think its the transmission input seal or anything like that. Also getting an occasionally intermittent neutral indicator. Are there any other possibilities for leaks? It's not the shifter, not the fill or drain plug.

Thanks guys, getting the bottom of this bike nice and dry is my main focus for may, i've getting a garage space with access to a lift and some help for that month, so i want to make the most of it.

also, the suggestions from faibox and mr. glaves on the fork oil are paying dividends, 15ml extra has made a difference, gonna try adding 10 more. :thumb

kourt999

04-20-2009, 10:10 AM

I did the whole thing last summer--new pushrod seals, etc. I don't quite know why there's so much fuss about removing the pistons from the jugs--they are easy to put back in, as long as you're careful about offsetting the ring gaps and gently using your fingers to get the rings into the bores. If you don't want to remove the pistons, go get a circlip tool, remove the circlip holding the wrist pin, pop the wrist pin out and remove the piston and jug as a unit.

Of course, I cut my teeth rebuilding Honda inline four engines, so the boxer seems like a piece of cake to me. :whistle

kourt

Barron_Williams

04-20-2009, 03:21 PM

I had a neutral indicator that started leaking one time. Although, your mention of false neutral indications maybe means it has loosened slightly rather than leaking where the plastic body is enclosed by the metal?

Perhaps you can get underneath and clean it up while confirming that it is tight? Once it is cleaned and tight, you should know shortly if the leak is coming from the neutral switch.

Not sure about your year/model, but on mine, if you do have to replace the switch, you can do it without pulling the transmission by removing the rear engine mounting bolt and the spacer (put it in the freezer while you are working so it goes back in easier). Two other lessons I learned - there are two type of switches, normal open and normal closed. If you get the wrong one for your bike it will be an "in gear" indicator rather than a neutral switch. Also, you might have to add another washer to get the fit right. Test it to make sure it is working right as you go in and out of neutral before you button everything up.

Barron

mymindsok

04-20-2009, 06:34 PM

Put your bike on a lift and spend an afternoon cleaning it up. Then you'l be able to see exactly where the leaks are.

If the neutral switch is leaking, you should be able to see that pretty clearly as a drop of oil on the switch but as above, clean everything up including the push rod seals and then look for more leaks. None of these jobs are as difficult as they appear to be and once plugged up, the leaks tend to stay dry for a long time.

Absolutely the first thing I do when I get a new-to-me Airhead is to clean it up, degrease the engine, get rid of all of the leaks and lube the splines. Only when thats all done, do I start tracking down the other issues with the bikes.

squiffynimrod

04-20-2009, 07:29 PM

BubbaZanetti

04-20-2009, 08:51 PM

thanks guys, keep it coming! that pictorial was great! if that's + the neutral switch is all it is i'll be quite happy.

any other thoughts on the gear box leak? other sources?

PeoriaMac

04-21-2009, 09:08 PM

Bubba --a tip. When replacing the neutral indicator switch, make sure that little washer goes back on. Not only will it stop leaks...but otherwise the indicator goes up too far into the tranny. Then you're bike won't shift out of first. Disconcerting and annoying. Do a tranny check through the gears before taking it off the workstand.

Mac

sumran

04-22-2009, 07:02 AM

Have you verified the oil is gear oil (smell test)? If you have leaking push rod seals the oil ends up on the neutral switch because of airflow. It migrates along the top of the oil pan and coats the underside of the tranny and drips off of the switch. It also coats the frame rails and the centerstand. I know a few guys that have replaced their pan gasket and neutral switch, only to discover that the PR seals were the source of the oil.

osbornk

04-22-2009, 08:00 AM

I don't know how bad your tube seals are leaking. When I bought my airhead, the owner had just changed the oil and put synthetic in it. Shortly after I got the bike, the tube seals started leaking enough to drip when I parked it. I changed the oil to conventional oil and the leaking stopped. It has been 10 years and I have had no further problem.

108625

04-22-2009, 08:39 AM

thanks guys, keep it coming! that pictorial was great! if that's + the neutral switch is all it is i'll be quite happy.

any other thoughts on the gear box leak? other sources?

Derek,

That switch runs about $50 and is a pain to replace. Workin with the bike on its centerstand, you pretty much have to remove the rear engine mount and spacer to get room to work on it. The metal part of the body is very thin, soft aluminum, be gentle with it.

If you're not sure that's the source, the input shaft seal of the transmission could be. It would leak out of the bell housing vent just like a rear main seal would, and put gear oil on top of the sump just like the neutral switch would.

Welcome back to the real world of airheads:bolt

BubbaZanetti

04-22-2009, 12:32 PM

Derek,

That switch runs about $50 and is a pain to replace. Workin with the bike on its centerstand, you pretty much have to remove the rear engine mount and spacer to get room to work on it. The metal part of the body is very thin, soft aluminum, be gentle with it.

If you're not sure that's the source, the input shaft seal of the transmission could be. It would leak out of the bell housing vent just like a rear main seal would, and put gear oil on top of the sump just like the neutral switch would.

Welcome back to the real world of airheads:bolt

one of my worries, i kinda hope its the neutral switch.

yeah, i smell tested it, it's gear oil, but i've also got leaky PT seals. i'm gonna clean it all up and find the real source before i dig too deep.

crazydrummerdude

04-22-2009, 06:23 PM

i'm assuming you have to disconnect the piston from the con rod

On my R75/6:

http://img.photobucket.com/albums/v469/aretnap69/bmw/20080417012.jpg

You can even leave the head on, although this will stir head-gasket debate:

http://img.photobucket.com/albums/v469/aretnap69/bmw/20080417011.jpg

2. I'm leaking a healthy amount of gearbox oil

Also, I had a pretty bad leak that I wasn't sure about for a couple days. It was my oil indicator leaking down the wire and onto the frame.

http://img.photobucket.com/albums/v469/aretnap69/bmw/20080327181.jpg

In this picture, you can also see the split pushrod tube seal that I was replacing in the previous pic(s).

Be sure you put them on straight, and don't use crappy after-market seals. (I had 3 out of 4 split a few days after proper installation.)