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ridesitall Mon Dec 27, 2004 10:55 am

I'm burning a puff of blue every time I shift, but thats the only time it will smoke.
Any idea why it only smokes on shift?

keifernet Mon Dec 27, 2004 11:45 am

valve guides or rings worn... :idea: :?:

try putting a can of Restore in it on your next oil change...

http://www.restoreusa.com/faqs.html

you can get it at Wal-Mart the cheapest place I have found.

I have used it in my high milage water cooled vehicles ( and so have some of my friends/ family) with very good results.

I have been putting it in some VW engines, but they are not my cars so I won't know the results on them until next time they are in for service.

chickengeorge Mon Dec 27, 2004 1:14 pm

ridesitall wrote: I'm burning a puff of blue every time I shift, but thats the only time it will smoke.
Any idea why it only smokes on shift?

When you are under load, the oil going into the cylinder is burned more thoroughly. When you let off to shift, the oil doesn't burn off as well and you see the result. You have oil getting into the cylinder from one of the areas listed in the previous post. That's your major problem.

Eaallred Mon Dec 27, 2004 9:47 pm

Another vote for valve guides. That's about the only time you'll get it to smoke from the tailpipe. If it were rings, it would be excessive smoke from the breather system.

When you take it up in gear, and let off the gas to shift, the butterfly in the carb closes, but the engine is still spinning at a decent rpm. The engine speed, combined with the closed throttle, creates a lot of manifold vacuum, and if the valve guides are worn, then it will suck oil past them like a kid with a capri-sun.

69 Jim Mon Dec 27, 2004 11:44 pm

I vote rings are worn. Actually I don't think it really matters, it sounds like a total teardown is coming unfortunately. :(

undwirtanzten Mon Dec 27, 2004 11:56 pm

if you haven't already...i'd suggest making sure you keep your heater channels open....even if they don't do anything to heat up your interior, they provide a much lower temperature that will keep you from burning through as much oil as you are right now....it might even be enough to stop it altogether temporarily (until you can get around to the rebuild...). the hotter your oil, the higher your oil pressure, and the more stress to your leak....so baby it until you can fix it.

69 Jim Tue Dec 28, 2004 12:09 am

undwirtanzten wrote: if you haven't already...i'd suggest making sure you keep your heater channels open....even if they don't do anything to heat up your interior, they provide a much lower temperature that will keep you from burning through as much oil as you are right now....it might even be enough to stop it altogether temporarily (until you can get around to the rebuild...). the hotter your oil, the higher your oil pressure, and the more stress to your leak....so baby it until you can fix it.

What does oil pressure have to do with worn rings or guides? Thirty years in the hobby and I learned something new about the heating system. :roll:

undwirtanzten Tue Dec 28, 2004 12:32 am

the higher the oil pressure, the more oil leaks in where it's worn. the higher the oil temp, the higher the oil pressure (by volume). it's simple physics applied to mechanical systems.....

69 Jim Tue Dec 28, 2004 12:38 am

Thanks for clearing that up. :roll:

undwirtanzten Tue Dec 28, 2004 12:42 am

no problem....think of it like a balloon with a hole in it. air leaks out slowly. when you increase the pressure on the balloon by squeezing it, more air comes out. the only difference is that the container isn't shrinking, the liquid inside is expanding (when you heat a substance up, it expands).

keeping your heater channels open keeps fresh air flowing through the oil cooler, which in turn keeps the oil circulating at a lower temperature.....

ridesitall Tue Dec 28, 2004 11:35 am

Thanks for all the info guys.
Heater boxes are removed, so they are always open.
I was wondering if it was possible that to much fuel was going into the cylinders and washing them and allowing any small amounts of oil to be burned? Webber progr. is installed.

Seb67 Tue Dec 28, 2004 12:06 pm

I guess the first question to ask is, how old is the engine? Has it been rebuilt recently (professionally or by you) or is its previous maintenance history unknown. Have you had the motor a long time and do you know how it behaves OR is a motor that is new to you. It's difficult when we come across an unfamiliar motor. Maybe at first it runs okay -- you know, you do all the regualr maintenace stuff :set valves, points, timing,oil etc. Only to find that the engine is really at the end of its useful life and i'ts time for a rebuild. I cast my vote in the worn valve guide camp.

keifernet Tue Dec 28, 2004 12:10 pm

67Jim wrote: undwirtanzten wrote: if you haven't already...i'd suggest making sure you keep your heater channels open....even if they don't do anything to heat up your interior, they provide a much lower temperature that will keep you from burning through as much oil as you are right now....it might even be enough to stop it altogether temporarily (until you can get around to the rebuild...). the hotter your oil, the higher your oil pressure, and the more stress to your leak....so baby it until you can fix it.

What does oil pressure have to do with worn rings or guides? Thirty years in the hobby and I learned something new about the heating system. :roll:

Hotter oil gets thinner and you generally LOOSE oil pressure behind the bearings etc... I agree with Jim...neither the heater channels being open or oil pressure has anything to do with this guy's trouble.

thesponge Tue Dec 28, 2004 1:50 pm

Wouldn't thinner oil get through a leak faster than thick oil??? I thought that was one of the things engine restore did. Not trying to argue just play devils advocate :twisted: Anyway I would place my hat in with the worn valve guides. But keep in mind you rebuild the top end you need to do the bottom also otherwise you are asking for trouble. Take an old engine and make one part new you will just weaken the part that is still old.

keifernet Tue Dec 28, 2004 1:55 pm

thesponge wrote: Wouldn't thinner oil get through a leak faster than thick oil??? I thought that was one of the things engine restore did. Not trying to argue just play devils advocate :twisted: Anyway I would place my hat in with the worn valve guides. But keep in mind you rebuild the top end you need to do the bottom also otherwise you are asking for trouble. Take an old engine and make one part new you will just weaken the part that is still old.

I'm not arguing either! :lol: it's the "higher the oil pressure" I just don't agree with... yes thinner oil will burn easier/ leak etc... but hot thin oil looses pressure not the other way around.

The restore stuff helps to seal worn cylinders and rings... it did the trick on my high milage daily driver toyota camry... not sure if it will cure worn guides on the VW engine though...

http://www.thesamba.com/vw/forum/viewtopic.php?t=87114&highlight=restore


changine to at least 20w50 and some of it may help his engine live until he can afford to build it or build another while he is still running around on this one.

Hippie Tue Dec 28, 2004 5:19 pm

I vote with the, "you'er gonna have to pull the heads and at that time you're gonna wiggle the valves and might as well yank the cylinders since they are just flopping there now that the heads are off and check your ring gaps, etc., so what does it matter where it's coming from and could really be either or both places," crowd.
:)

undwirtanzten Tue Dec 28, 2004 9:44 pm

yes, hotter oil gets thinner. what happens when an oil gets heated up and gets thinner? it's density decreases, but it's volume increases, as the amount of mass can not change. meaning it takes up more space. the pressure built up in the oil has nothing to do with it's viscosity (density/thickness/whateveryouwill), but everything to do with it's volume. you loose oil pressure when you have a leak or clog in the system, not when your oil gets too thin.
i'm not saying keeping the heater channels open has anything to do with this guys problem other than it will help him save on oil until he gets around to rebuilding and fixing his valve guide problem.

turboblue Thu Dec 30, 2004 11:27 am

Quote: yes, hotter oil gets thinner. what happens when an oil gets heated up and gets thinner? it's density decreases, but it's volume increases, as the amount of mass can not change. meaning it takes up more space. the pressure built up in the oil has nothing to do with it's viscosity

You need to explain this a little better to me. I think I am reading that when the oil heats up, the pressure increases? How can that be. The oil system in the engine has a controlled leak. The bearing clearances.
When the the oil becomes thinner, the "leak" through the clearance in the bearings becomes more prominent. Then the pressure will drop to a point where the pump will keep the pressure up that certain point through sheer volume.

turboblue Thu Dec 30, 2004 11:32 am

ridesitall wrote: I'm burning a puff of blue every time I shift, but thats the only time it will smoke.
Any idea why it only smokes on shift?

My guess is the valve guides or rings too. Try the restore. If that doesn't help, an upgraded breather system that vents the valve covers as well as the crankcase might help you get by until you can positively diagnose the problem. Or you can let it puff till you figure it out too.

undwirtanzten Fri Dec 31, 2004 1:15 am

[quote="turboblue"] Quote:

You need to explain this a little better to me. I think I am reading that when the oil heats up, the pressure increases? How can that be. The oil system in the engine has a controlled leak. The bearing clearances.
When the the oil becomes thinner, the "leak" through the clearance in the bearings becomes more prominent. Then the pressure will drop to a point where the pump will keep the pressure up that certain point through sheer volume.

right. the leak in the system (bearings) is what releases the pressure. not the oil being thinner. you guys are missing the point, opening the heater channels and letting the heat escape the engine compartment makes the engines run at a cooler temperature.....that's how the air cooled system works. you cool off the oil by passing air through it. what happens when you plug off the channels through which the heat escapes? it stays there. ultimately, running the engine at a cooler temperature is gonna save our friend here a little money by taking away a little of his oil loss.



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