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Oil from left carb?

T

TELLURIDER

Guest
I have oil comming from somewhere that ends up on the bottom of my left carb and keeps ending up on my left foot. Any ideas where this oil could be comming from? It smells like it might have a little gas mixed in but mostly it's oil. Oh yeah 82R100RS.
 
The Oil pressure sender unit is up in behind the carb. Mine leaked...may even still be leaking a little with a new sender. '83 R80RT
 
Thanks, I'll have a closer look and see if that's where its comming from. is it a tapered thread that might need to be tightened or does it have a gasket?
 
Tell,

I don't remember if it was with gasket, or not, but I don't believe it was leaking from the threads. As I recall, it was leaking from around, or between, the electrical connector and the the hard plastic in which it is encases.

It's been some time since I changed it, and I'm not riding the bike much anymore. The new RT took over.

Gary
 
oil from left carb

My R80RT (84) is leaking from the same area. I see it coming from the oil pressure sending unit. Now, where can I get one? Haven't looked very hard yet. Any ideas?
1der
 
Any Dealer probably has it available. I'm still getting parts for mine. Last year, I got a new dash board, and I suspect that would go out of print long before the sender unit. I also suspect the sender fits a lot of different models, but I don't know that for sure.

Gary
 
It turns out it wasn't the oil presure sender although it looks like it may be leaking a very small amount. It was comming out of the air tube from the crank case breather tube. The hose clamp conecting the tube to the carb wasn't compleatly tight and so it was leaking out and ending up on the bottom of the carb. I cleaned it all up and put it back together and got the hose clamp tight.

One question though, is it normal to be seeing oil comming out of the breathers?

I checked my oil and it isn't too full it is right at or a little below the top full mark. It's not a lot of oil, only a couple of drops every time I ride. Will this end up gunking up my carbs? I wonder if I should keep the oil level a little bit lower.

My old 77 didn't have the crank case breather tubles like this and I don't actualy remember where its breather was so this is new to me.

Thanks,

Dan
 
A little oil is somewhat normal, but you might have some excess blow-by, creating an extra level of oil mist which goes out the breather. You might also want to check the small hole in the engine case just forward and to the right side of the starter. This is a hole in the bottom of the path that the oil mist takes on the way to the carbs. The hole is designed to allow any condensed mist to drip back into the block. You'll need to remove the starter cover and locate the hole...a small wire can be used to poke through the hole. Don't drop it into the engine...that'll kind of ruin your day!!
 
What do you mean by valve tubes? Push rod tubes? Valve guides?

Just a couple of thousand ago it had a pretty through going over by WUMA Inc. "By Gunther" in Fredericksburg IN I don't know anything about them but the guy I bought it from has a half dozen airheads and couple of oil heads and he has all his work done there.

They did a complete top end job mesuring the valve guides, new exhaust valves and seats, and new exhaust guides, and pushrod seals.

This was done before I bought it but I have the invoice for the work so I think the top end should be all in good shape. I would like to give Gunther a call and ask him some questions about the overall condition of the engine. It has just over 70,000 miles but since I don't have all the service records from the beginning who knows it could be 170. I'm sure the person I bought it from wouldn't have lied about the miles but he bought it from the original owners wife. I'm not sure of the story there but he didn't get the service records.

I haven't had it for long and I have been busy, we have had a lot of snow and bad weather this spring so I haven't taken the time to give it a through going over. I also haven't had time to ride it much, but it was well serviced before I bought it with the full top end job, carbs rebuilt, brakes flushed, new rear rotor and pads, full fluids change and filters, new Ikons in back and new progressive springs and seals in front.

I rode it home from Kentucky and it ran great it idles smooth at around 6 or 700 rpm and in almost 2000 miles it has used less than a half a quart of oil. The last owner torqued the heads and adjusted the valves before I bought it and I just checked them and they were still adjusted.
 
A little oil is somewhat normal, but you might have some excess blow-by, creating an extra level of oil mist which goes out the breather. You might also want to check the small hole in the engine case just forward and to the right side of the starter. This is a hole in the bottom of the path that the oil mist takes on the way to the carbs. The hole is designed to allow any condensed mist to drip back into the block. You'll need to remove the starter cover and locate the hole...a small wire can be used to poke through the hole. Don't drop it into the engine...that'll kind of ruin your day!!

If that's pluged it will cause the oil to go straight out the breather insted of recondensing?

Does this happen very often?
 
If that's pluged it will cause the oil to go straight out the breather insted of recondensing?

Does this happen very often?

Yes, if the oil doesn't drip back into the block, it will have more of a tendency to remain airborne and go out the carbs. This is an '82, right, and should have tubes going out both carbs, IIRC. I only have the right side tube on my /7. If that's the case, then it would seem a little strange that only the left side carb has the oily deposits. Possibly there's something amiss with the breather system under the starter cover, as in one side might be plugged or disconnected.

I have no personal experience but I had heard about this little hole and made sure mine was clear when I changed to the new breather style. It's something to check...but I believe you have to remove the cover to the breather valve to get to the hole. Look at this picture someone posted on the Airheads forum:

http://homepage.sunrise.ch/mysunrise/joerg.hau/mot/img/valeo01.jpg

See the well just below the silver portion at the rear of the starter...that's where the small hole is. This whole area, including the breather valve should have a cover over the top of it. There's another well forward on the case which should have another cover on it. The oil mist travels out of the breather into the rear well then through a void in the block to the front well. The front cover will have a tube coming out of it that routes the air back to the carbs...it's the large diameter tube on the opposite side of the starter in the picture. BTW...I suspect this is a Valeo starter as the URL name suggests.

If you're only loosing about 1/2 a quart in 2000 miles, that's almost nothing relatively speaking. Of course the drip is annoying and it would be nice to find it. Another suggestion...600-700 RPM at idle is a bit low, IMO. It should be more like 1000-1100. If the idle is too low, you might not be getting sufficient oil pressure to keep the bottom end bearings lubed. I believe that's the first place the oil goes after the oil pump.
 
Thanks Kurt,

It does have breather tubes on both sides and the oil does come out of both its just that the air tube was a little loose on the left so that's where it was dripping. Also it leans to the left when it is parked on the side stand which is all of the time (it just dosen't seem worth it to fight it up onto the center stand)

I will check out that hole and make sure it is clear as soon as I get a chance. It looks like it is going to rain so it could be a good project for tomorrow (in the garrage)

Yeah I know the idle is low, thats one thing the guy I bought it from told me is that Gunther likes to set it like that, Not sure why? I don't have a balancer but I would like to turn the idle up to around 1000, it dies sometime when you come to a stop. I also need to rejet it for the altitude I will probably have this done here localy and I will get the idle set at that time.
 
Have you seen the $4 synchronizer? With prices these days, maybe it's $5 by now!

http://www.airheads.org/content/view/183/98/

Assuming the bike is relatively OK from a synch standpoint, you could easily bump up the idle evenly on both sides. Find the idle speed adjust screw and turn 1/2 revolution on each side...see what the idle speed is...adjust more if necessary. There's a whole process for balancing the carbs, but this should be good enough for the near term. I know what you mean about dying coming to a stop...a little disconcerting.
 
Wow that sounds great! great instructions on ballancing too. Have you made one for yourself?

Right now my carbs are well balanced but it would be great to have a sychronizer I used to go to a friend who has a four tube mercury one that had one of the tubes broken (only needed two).

too bad the hardware store is closed on Sundays here, or I would make myself one tomorrow.
 
I've never made one of those manometers before, but I've heard a lot of people have. I haven't paid enough attention to it, but it may need some kind of damper to keep the water levels from bouncing too much...maybe that's built in. I bought a TwinMax a number of years ago so that's what I use. I still have my mercury Carb Stix that I bought probably 20 years ago. I bought it for the Honda 750-4 I had at the time. I remember using it and having to deal with the bouncing mercury columns...it didn't have any way to minimize the pulses from the engine.
 
When I used the mercury balancer it did bounce but you just watched where it bounced to and as long as it was even it seemed to work ok.

I wonder if the $4 balancer dosen't bounce because it is a loop with one end conected to the left carb and the other end conected to the right carb. Maybe the carbs both pulling on the fluid from opisite sides works to eliminate the bouncing.

In the directions it said you can fill it with water or automatic transmission fluid or oil I would think something more viscous might work better than water.
 
When I used the mercury balancer it did bounce but you just watched where it bounced to and as long as it was even it seemed to work ok.

I wonder if the $4 balancer dosen't bounce because it is a loop with one end conected to the left carb and the other end conected to the right carb. Maybe the carbs both pulling on the fluid from opisite sides works to eliminate the bouncing.

In the directions it said you can fill it with water or automatic transmission fluid or oil I would think something more viscous might work better than water.

I made one a week a go, works like a champ, it bounces, but it is minute, you can tell very easily when they are matching up...Best 4 bucks I ever spent. :thumb (the hardest part is getting the bubbles out...takes a day or so)
 
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