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What is a "Ring Job"?

My grandfather used to say he never had a ring job he was satisfied with. I am sure this had something to do with a rehab of the engine, but does anyone know or can explain what happens? I keep thinking of the Rings of Saturn, but I doubt this has anything to do with astronomy.

He’s talking about an engine rebuild, specifically replacing the piston rings that help seal the combustion chamber. However, if a mechanic just replaces the rings, without removing the engine and having the cylinders rebored, he’ll end up with an engine still may burn oil. These may be the ‘ring job’ your granddad wasn’t happy with. I know, I did one when I was 16, and the engine, while better (it had a blown piston, after all) still burned oil and fouled a plug. Live and learn…

Back in the old days, when some people claim that cars were “much better made” than they are today, it was very common for an engine to need a “ring job” and a “valve job” by 50,000 miles.

The ring job entailed disassembly of the engine, removal of the old piston rings, and installation of new piston rings. The pistons use several rings, for two purposes–containing compression in the cylinders and keeping crankcase oil from getting into the cylinders. After 50k miles, it was fairly common to see cars trailing plumes of smoke every time that they were accelerated, meaning that the oil control rings were worn, and for there to be a drop in power output, meaning that the compression rings were shot. Frequently, there was sufficient wear in the cylinders to also necessitate reboring the cylinder slightly. Replacing the rings correctly could give an engine a new lease on life for another 40k-50k.

The valve job, which frequently accompanied the ring job, involved grinding accumulated carbon deposits off of the valves and the valve seats in order to restore compression to the engine. The carbon deposits on the valves were the result of very poor combustion–a problem rarely seen on modern engines.

As a result of better metal alloys for engine parts and as a result of vastly improved motor oils, neither of these procedures is normally part of the maintenance plan for engines nowadays, and even the cheapest cars of today can usually operate for well over 150k miles without this type of procedure–as long as they are properly maintained.

Whenever I hear someone say, “They sure don’t build cars like they used to”, my response, is, “Yes, thank God”.

Getting married might be called a “ring job”!

Seriously, a ring job on an engine means putting new (larger)rings on the pistons and remachining the cyinder walls for a better fit. Some major ring jobs involve new pistons as well.

A good shop can do a great job. Our original car when I was a kid, a 1941 Chevy 6, had its rings and valves done by a local mechanic. The engine outlasted the rest of the car, and my brother-in-law bought the engine to power a welding machine which he ran for another 30 years!

So, there are ring jobs and ring jobs; the good ones will basically give you new car performance, if that’s all the engine needs.

Sorry to hear you grandpa had bad luck with his. One thing, NEVER try to cut cost on internal engine work!

P.S. The great ring and valve job done on our 1941 Chevy 6 was done in the car with only the head and pan removed. The garage was a small town operation and both a Chrysler and International Harvester farm equipment dealer.

Each piston as a set of “rings” that ride against the walls of the cylinder. The rings separate the gasses and combustion materials at the top of the cylinder from the oil and lubricants at the bottom of the cylinder.

The rings are open loops so that they are flexible and glide smoothly against the cylinder walls. Several rings are used to make sure everything seals effectively. Worn rings allow oil to get into the combustion chamber and you get blue smoke from the tailpipe and may have to add oil frequently to replace burned off oil. Worn rings also don’t hold the pressure in the combustion chamber and the motor will lose power and if bad enough not have enough compression to ignite the fuel/air mix. The symptom is you’ll lose a cylinder and the motor will not run smoothly.

In the old days (20’s, 30’s, 40’s, 50’s) ring jobs and valve jobs were very common. Gramps is saying that a new motor might run good for 4 years and 30K miles but once it had a ring job it would need the same repair again after only 2 years or 20K miles. A proper ring job involves honeing cylinders to smooth them out and then installing slightly larger rings to compensate for cylinder wear. Lots of room for error so many jobs were not so well done and didn’t hold up very long.

A properly done ring and valve job by a skilled mechanic would last just as long as a new factory engine but there were lots and lots of less skilled mechanics doing the work.

And these days, you’ll very rarely hear about this, most engines last the life of the car, and if not, a rebuilt engine, or a new ‘crate engine’ is swapped in for the bad one. One of the few times someone will go to the trouble of actually rebuilding the engine is for a collector’s car, where it’s important to have the original ‘numbers matching’ engine when it comes time to sell.

When cylinders are worn, they dont usually wear evenly. In such a case, the cylinder is re-bored, or machined to a larger diameter, and then new pistons will be needed.
If it is only a problem with the rings, such as collapsed rings (they lose thier spring tension against the cylinder wall due to overheating) and the cylinder wall is not damaged, then honing the cylinder is done not to change the diameter but to give a slight roughness (not smoothness) to the wall. This allows the new rings to wear to fit, or “seat” on the cylinder wall, and it insures that there will be oil retained durring the break in period on the wall to ease this seating process. There are two kinds of cylinder hone, a bottle brush hone, and a three stone hone. The former is much easyer to use correctly, but speed of the hone motor, duration of honing, and the rate at which the hone is moved up and down in the cylinder, as well as how well the grit that results from honing is removed after honing all affect the outcome of a ring job. I hope this informaiton is helpfull.

A ring job can be done satisfactorily if it’s done properly and things are within spec.
This means the cylinders must be measured for taper and out of round, rings must be set up properly in the piston lands (grooves), the cylinders honed with a proper cross-hatch, etc.

Unfortunately, measuring cylinders with micrometers is time consuming so often what was done was that a hone was brushed through the cylinders, rings installed on the pistons, and it was called good.
Needless to say, a round piston ring installed into an oval cylinder hole is not a good fitment; especially if the hone was a bottle brush type.

Others have explained the purpose of the piston rings. Through the 1950’s, it was possible on most cars to take the engine apart without removing the engine from the car (Studebaker was an exception and there were probably others). The oil pan and the cylinder head would be removed, the valves were ground and new rings wee fitted on the pistons. There were expansion rings available to help compensate for wear on the cylinder walls. This “overhaul” was usually good for about 20,000 miles.

A better solution was to install a rebuilt engine. These engines were even available for most cars through the Sears Roebuck or Montgomery Ward catalog. With a rebuilt engine, the cylinder walls were rebored, the crankshaft throws turned, the camshaft reground, etc. and then new piston rings, bearings, etc. were fitted so that the engine was essentially like a new engine.

My Dad owned a 1939 Chevrolet that he purchased new. Just after WW II he had new rings and a valve job at 70,000 miles. The mechanics at the Chevrolet dealer were amazed at how far he had driven on the original piston rings. The engine had another ring and valve job at 105,000 miles. He traded the car at 110,000 miles.

Today, most engines have to be removed from the car to do major work, so it makes even more sense to install a facuolty rebuilt engine.

Until the mid fifties, Chevrolet engines used babbited rods that were bolted to the piston and could be easily(?) removed without disturbing the crankshaft. Portable cylinder boring machines were available. In fact, there were crankshaft lathes that would dress a throw without removing the crank. Re-ringing was common. Ramco Ten-Up rings were a big seller. They were touted as being able to breach a gap up to .010 between the origial piston and a worn cylinder after minor glaze breaking.

I remember seeing advertisements in magazines for Hasting’s piston rngs–“Tough on oil consumption, but gentle on cylinder walls”. I also had some repairs done to my car while in graduate school back in 1962. The mechanic was working on a 1949 Chrysler that burned out a connecting rod bearing. A machinist that traveled from garage to garage had a portable crankshaft lathe and turned the journal of the crank of the Chrysler so an undersized bearing could be fitted.

Your Grandfather was speaking of the rings around the Moon!!

It has taken field mechanics over 100 years to learn to LEAVE THE RINGS ALONE!!! You can make a lot more money repairing and recharging air conditioners and making the Check Engine Light go off…

One of the main reasons cars needed frequent “ring jobs” was the crude air-cleaners they used, usually a poorly maintained and marginal at best “oil-bath” contraption that struggled to remove the fine, wind-blown dust…That’s when half the people in the country lived on dirt roads…

A ring job describes just changing the rings which surround the piston. There are several type of rings, but put simply they (rings) are seals which seal in compression and limit oil loss. Why anyone would go to the trouble of just changing the rings and not addressing the rest of the motor when you are this far into it is incredible to me. Rocketman

I don’t know where a comprehensive guide could be found but I find the “tricks” that machinists came up with during the shortage years of WWII to be very interesting. On the note of "war years’ I send out a “Thank You” to all veterans.

How about old Tom Joad in Steinbecks “Grapes of Wrath”, did he not do a bearing job on the car they were using to get to CA? or was this a ring job? I remember some of this book very well.