lol MG, my jeep has a broken back window washer fitting. it squirts straight back.
I have only used it on friends and family so far. I m a little afraid of road rage in my old age…
That is something to think about in this day and age.
One of the Geo Metro engines I tried this “Italian tuneup” on was beyond fixing without a complete rebuild. You could pretty much count on it puking massive amounts of oil into the throttle body if you had it under load for a couple miles or more in a high gear. This usually happened on big hills at highway speed or a sustained headwind. This engine burned so much oil you would have to add at least a quart every 100 miles. I had a couple times where people yelled when it smoked up the entire highway. I could see cars and semi’s pulling over behind me. Those are the ones I could see; the others were hidden by the cloud.
The PCV system on these cars isn’t much and this isn’t an unusual problem as they age. People call it an oil fart. I was coming home from a couple hundred mile trip with this car and had to buy several containers of oil at an auto parts store to make it home and I knew it was time to do something. I was pissed off so when I came to a lonely stretch of road, I just kept it floored for several miles. It spit and sputtered and blew out the biggest cloud of smoke ever. I pulled in to the next gas station, started filling up, and added a quart of oil without even checking before. It was still a tad low and I added some more.
I went searching for a viable used engine and came across a good one without this problem. You always want to look under the air cleaner for pooled oil when buying one of these cars or engines.
“even if they were the same material they would not expand the same. the mass and shape are different, which makes them expand differently”
I don’t think so. Expansion is a function of only the temperature coefficient of expansion and the temperature change. However, if you mean mass and shape affect the temperature distribution, then I would agree.
obviously…
if you put the same amount of heat on the center of one leg of a small steel angle iron 2 x 2 x 1/8 @ 1ft long
and a 8 x 8 x 3/4 pc @ 1ft long the small pc will distort when heated and bend a great deal back in the other direction as it cools, while the large pc will barely move unless you use a great deal more heat. if you do this with an angle and a different shape such as a flatbar or channel they will bend differently too.
I don t even get what you disagree with…
If your piece of steel is put in a large oven and heated uniformly, it won’t warp. That’s the point, I think. Uneven heating will result in uneven expansion.
What texases said…
obviously. but shapes are under stress after they are shaped. if you put a 40 ft angle in a large oven and heat it enough it will warp as it heats and cools because some tension is released.
if you did that with a round rod or square bar it may not warp. but a channel will warp in the situation you describe because of the release of stresses caused in the shaping process.
heck a channel will warp just sitting in the sun
“… a channel will warp in the situation you describe because of the release of stresses caused in the shaping process.”
How does this apply to engine blocks and pistons?
nevermind, you are determined to disagree if I say the sky is blue, yeah I know its grey when its cloudy
semantics, schemantics…
This thread is the first time I’ve ever heard of an “Italian Tune-Up”…Freeing stuck rings without removing them from the piston has to have a low percentage of success…You might get lucky once and a while, but not very often…
I have also heard of piston soaks where you put Seafoam or Marvel Mystery Oil and compress air using a leakdown tester to force the solvents down into the ring areas. I had one engine where I tried everything and nothing worked. It is always nice when you get away with doing something along these lines and getting it to work.
Also, if maintenance isn’t ignored by me like the previous owner(s), what are the chances of the problem returning? I am sure I didn’t clean out all the carbon around the rings.
Use a good synthetic and I’d be surprised if the rings re-stick.
Piston rings because even if a cylinder wall is exactly the same diameter from top to bottom it doesn’t stay that way. The piston speed is the highest in the center of the piston travel and wears the middle of the bore more than the top and bottom. Even if the wear was consistent, as soon as you got a few thousandths ow wear the rings couldn’t stay in touch with the cylinder walls if they were noT free to expand.
@Fender1325 Wow ok, now we’re getting somewhere. So all cylinders have a slight taper to them? Even from new? If this was the case, then the gap in the ring makes sense to me. That gives it room to compress where the cylinder walls are smaller in circumference.
No, not from new, it develops over time. The gap is required, even in a perfect wellbore, to account for manufacturing variation and, most importantly, thermal expansion.
I don’t know about car engines but there are engines with cylinder bores purposely tapered to offset the fact that the top of the cylinder runs hotter than the bottom. When the engine is at operating temperature, the cylinder walls become parallel. This practice is most frequently employed in model airplane glow engines which use ringless pistons. These engines will often stick at top dead center because when the cylinder is cold, there is a slight interference fit between the piston and cylinder.
It’s not just carbon that sticks piston rings, oil can be oxidized into a gummy varnish like residue.
I suspect the last engine I discussed was one of those where broken down oil may have played a role in the sticky rings. I am now running a European spec synthetic and hope it will help clean out the engine from its past neglect. The first oil change got really dark and dirty looking in only 500 miles. The next one doesn’t look so bad after 1000 so I am going to run it a while longer, possibly up to 3000 miles.
“Italian tuneups” were common in my younger days to clear out carbon, but I’ve never heard of them being used to free stuck oil rings. I’m not suggesting it won’t work, just saying the phrase was used differently in my neck of the woods.
Gotcha! I almost wonder if my problem was more related to the compression rings. See my above post about the limitations of the PCV system on this car. Since this sounds more suited to seating compression rings during break in, maybe this was the reason the engine stopped using oil. Someone also suggested that the rapidly changing stresses might also break the oil rings loose. Either way, we may never know but I am just happy the car quit using oil.
“Italian tuneup” reminds me of this Walter Matthau classic (“Never drive her under 3000 RPM in a forward gear. Ever!”)