Steps for replacing the valve stem seals ?

[EvenmoreXS]

You can lose a fair amount of oil over the mileage you're talking about from it seeping out or getting slung out where the stick goes in, if you're missing a good seal there. Cork is best and it's what came on it originally.

Another possibility is a loose head bolts. Oil can leak internally from a passage into a combustion chamber. Re-torque the head bolts, paying careful attention to what you're doing.

Also, an apparently competent rebuilder on here says his rebuilds use a qt of oil every 1000 miles. So if you were to rebuild you might not gain anything.

I can order a new dip shit seal. Stick, I mean stick !

Head bolts are unlikely, but I will check that last. I should see some smoke if its burning consistantly in combustion chamber. Very very little to no smoke now, and only on start up. When I put the head back on I checked the torque several times over 24 hours before adding oil and firing her up. Im certain the torque job was good. That was then, this is now.

Next oil change, I'll keep track of the amount of oil added and the rate of loss.

I did notice that I have 1 drip of oil under my bike a few mins ago... First drip Ive seen in 2 weeks parked in the same exact two spaces. Looks like it could be a slow seeping leak in the starter area. I do have the starter block off kit from mikes. Push rod seal is good. Could the starter be leaking a bit and would the block off help seal it. Im going to do some research into this tonight.

Thanks everyone

 

[gggGary]

start gearbox cover seal can leak. but enough to show up on the dip shit is going to leave a lake, not one drop in two weeks.

 

[deadchef]

if the nut on the front sprocket is loose you could be loosing oil past the driveshaft seal. could easily be mistaken for starter seal. also probably won't drip much as it inherently lubes the chain.

 

[EvenmoreXS]

Just a metnion I have a 79 about 20K miles runs great, no smoke, no drips, goes through a 1/2 quart every 300 miles. Stock air boxes and crank vent setup. I suspect an intake valve seal because I think an exhaust seal would smoke but don't know for sure. That engine just has to come out for a top, that's too much consumption for me.

Thats what I mean. The oil is going somewhere? My first thought was valve seals but no symptoms of that. I may be onto something with what I found this afternoon. First drip in weeks. Very small, just on drop under where the starter mounts. I plan to do a top end job over the winter, cam chain, rings, and valves mainly. New cam chain guide a few months ago. I will get a compression test done by my buddy at the yama dealer here and report back. Maybe tomorrow or friday.


Ggggary, You should read the post I post after your post before you post the post you post before my post.


Got it???

How do you feel about starter leaks? Kick only now, but could removing the starter and putting in the Mikes starter block help this. Any new gaskets Id need, it didnt come with any.?

 

[EvenmoreXS]

if the nut on the front sprocket is loose you could be loosing oil past the driveshaft seal. could easily be mistaken for starter seal. also probably won't drip much as it inherently lubes the chain.

This could be a posiblilty. The washer folds over the nut. Gonna be a biotch to tighten it, but I will look further into it. Torqe specs? Nut size? Best way to lock it down for a re-tighten? Worst case scenario if it is this, remove sprocket and put in new seal?


It could be this.

 

[xjwmx]

I should see some smoke if its burning consistantly in combustion chamber.

Motors don't smoke until they're in their death throes and burning oil faster than you can put it in. How much oil do you think you're using anyway? My impression for some reason was about a qt per 1000 mi. That wouldn't smoke.

 

[EvenmoreXS]

Motors don't smoke until they're in their death throes and burning oil faster than you can put it in. How much oil do you think you're using anyway? My impression for some reason was about a qt per 1000 mi. That wouldn't smoke.

No its not huge quantities, and Im still learning alot about older bikes, Im mainly trying to be proactive about potential problems so I can repair or prepare for repair depending on the necessisty. Everything Im doing is to make the bike last as long as possible. Maybe these bikes go through oil faster than my cars. But If I put 5 quarts of oil in my car and drive 3K miles, 5 quarts of oil comes out at the next change. Im either losing oil or buring oil. Id honestly prefer to lose it and add more than be burning it up in my cylinders.

I get the impression by the replies Im getting that this isnt detrimental and quite possibly is typical for this bike,..... age and all that stuff. I dont want to worry for nothing, but I want to be on top of any problems early too. Gotta walk that line. By next year this time I hope to have all new seals, gaskes, rings, and bearings.

Thanks Everyone

 

[xjwmx]

Best way to lock it down for a re-tighten?

I take a 10" piece of wood and stick it through the rear wheel and let the swing arm block it at the ends. Won't work with spokes. And keep the wood away from the valve stem.

 

[EvenmoreXS]

I take a 10" piece of wood and stick it through the rear wheel and let the swing arm block it at the ends. Won't work with spokes. And keep the wood away from the valve stem.

I have spokes. Any other ideas?

 

[xjwmx]

^You can fold up a towel and stick it between the chain and a sprocket. I suggest not putting it on the underside of the front sprocket because of the shifter and etc there.

 

[EvenmoreXS]

^You can fold up a towel and stick it between the chain and a sprocket. I suggest not putting it on the underside of the front sprocket because of the shifter and etc there.

Underside of front would mean righty tighty for the nut right? I havent Mucked with this before, but have seen a few things in my day with reverse threads due to spinning parts.

Righty tighty looks right inside my head.

 

[xjwmx]

Underside of front would mean righty tighty for the nut right?

I'm going to leave that up to you.

Another thing you can do is hire a fat person to stand on your rear brake

 

[EvenmoreXS]

I'm going to leave that up to you.

Another thing you can do is hire a fat person to stand on your rear brake

Underside and tightening would require going clockwise. Hence, righty tighty.

Thats fucked up. I dont know any fat people. I see way too many of them at walmart though. I have a couple of friends who are big boned, but they arent fat.

Gonna have to stand outside walmart and solicit fat people.

See the sign they post at walmarts here. Can you find the error? Im surrounded by greatness.

Opposite game. Heads I win, Tails you loose.

 

[xjwmx]

^That was the 1rd thing I noticed. I was actually going to suggest you recruit walmart shoppers, but enough is enough

 

[scabber]

If a seal is leaking a half a quart you should check the rear tire. Oil will show on the side wall. Well 5 quarts in a car no oil loss you have one hell of a good car. You can't expect an air cooled motor to do the same. Have your Yamaha mechanic friend do a leak down test on the bike. It will tell you more about the condition of the motor than a compression test. Torque the head as suggested earlier that old head gasket has been thru a hell of a lot heat cycles and might have shrunk over the years.

 

[EvenmoreXS]

If a seal is leaking a half a quart you should check the rear tire. Oil will show on the side wall. Well 5 quarts in a car no oil loss you have one hell of a good car. You can't expect an air cooled motor to do the same. Have your Yamaha mechanic friend do a leak down test on the bike. It will tell you more about the condition of the motor than a compression test. Torque the head as suggested earlier that old head gasket has been thru a hell of a lot heat cycles and might have shrunk over the years.

Did have oil on my rear wheel side wall until I replace the push rod seal a few weeks ago. No more oil on the tire or swing arm at all.

Head and base gasket are new as of January and no leaks there, been watching real close. No leaks on the outside anyway.

I have 2 good cars, surprisingly, but they arent air cooled. Thought about that part too, but wasnt sure how much that would come into play. Sounds like air cooled will burn a little oil, or use it, however you want to say it.

Im going to see if I can get a compression and leak down test. I didnt do anything with the valves or rings. Just replaced the gaskets and front cam chain guide. New brass washers and that stuff. Saving the actual re build for this winter. No oil around the valves ever that I have seen while setting valve lash.

Thanks everyone!

 

[EvenmoreXS]

Changed oil in the last week and its low today. Having a brain fart and cant remember which exact day, I have it written down at home. But I think it was this past monday night. So about 5 days. With the bike level, dip shit resting on the threads, its very close to the minimum fill line. My best guess is the sprocket seal. Push rod isnt leaking. I did find a small amount of oil coming from my right points cover, cam seal. Very little though. I'll tighten that up and tighten the sprocket nut. The chain stays lubed but still NO leaks under the bike. Sump pic attached.

In an effort to reduce the amout of oil im leaving somewhere, Im going to reset my valves, tighten the front sprocket nut, and tighten up the right cam cover, and maybe retorque the 4 outside headbolts.

I will also drop my pilot size one and raise my floats back to 22 or 22.5 mm to see if I can get some better mpg's. Seems like its gone down a bit since my last rejet.

47.5 pilot, 140 main, 21.15mm floats currently. 3 turns out on the mix screw. UNI pods. Havnt had time to tune the carbs yet.

 

[TwoManyXS1Bs]

You check oil level with dip stick resting on top of threads or screwed in?

 

[Jack]

Did have oil on my rear wheel side wall until I replace the push rod seal a few weeks ago. No more oil on the tire or swing arm at all.

Head and base gasket are new as of January and no leaks there, been watching real close. No leaks on the outside anyway.

I have 2 good cars, surprisingly, but they arent air cooled. Thought about that part too, but wasnt sure how much that would come into play. Sounds like air cooled will burn a little oil, or use it, however you want to say it.

Im going to see if I can get a compression and leak down test. I didnt do anything with the valves or rings. Just replaced the gaskets and front cam chain guide. New brass washers and that stuff. Saving the actual re build for this winter. No oil around the valves ever that I have seen while setting valve lash.

Thanks everyone!

Most likely your loosing oil through the rings(TOP) not seating. Chrome and Moly rings are the worst to get properly seated and in most cases will cause an engine to use oil. On my recent 3.1 engine built I went with plan old cast rings and I don't even bother checking the oil till 3000 miles cuz it's always on the full mark but I do randomly check for oil leakage and that's what I plan on using in my 707 build.

 

[XSLeo]

tomany, you check the oil with the bike on the center stand, bike warmed up, let set a few minutes, unscrew the dipstick, wipe clean, insert dip stick, letting it set on the threads, remove and see the level. Level should be halfway between the marks.
At this time you can check the level by screwing the dipstick in, you may find as I have that the level is at the upper mark. On my bikes I have the site window as well. With the level right on the dipstick the site window shows it at the upper line.
Now if you have a bike without a centerstand hold it as straight up as possible while checking oil level.
Leo