Re ringing a cylinder with a ridge in it ?
 

Before you all pick on me, I never do this . I've built a ton of motors over the years, and I know the right way to do it .
Not on this one though, I am putting a big bandaid on this old roll back truck that I drug home . I need very little time from this motor, if I get 5 k miles out of it , I will be thrilled . I bought this truck for the jer dan roll back bed, but I actually got it to run and drive after sitting for 11 years , and it actually ran ok . I drove it 11 miles home.
We did the normal stuff to try to bring it back to life , but the rings were all stuck, and 5 of the cylinders ended up having broken rings.
So I am going to do a quick and dirty in frame rebuild . Hone it , new pistons, rings , rod bearings, cam , lifters valve, job, oil pump and timing chain . . I am doing this in my side yard at home, not at the shop .
There are some mild scratches in the bore, but even in this shape, with broken rings , and a bad cam, I still got 120 psi out of each hole, so I am not going to fret over this too much
There is however a decent sized ridge on the top of the bore .I did not ridge ream it , I was able to push the pistons out by hand over the ridge, and after honing , the ridge is a very mild transition , and does not really catch on my fingernail , but none the less, is still there .
My worry is that the new rings will constantly pound on this ridge and break them . Would you ream it off, or just drop the slugs in and send this bastage down the road ? I have a reamer sitting here, I just do not want to make the top of the bore any larger than it already is
I had not planned to get into the motor at my house like this, but I started tinkering one evening , and next thing I knew, heads were off , and I figured I was all in at this point
Here are some photos http://forums.pelicanparts.com/uploa...1495849215.jpg
http://forums.pelicanparts.com/uploa...1495849235.jpg
Here is the specimin
http://forums.pelicanparts.com/uploa...1495849387.jpg

. Ugly old truck but I can work it while I look for a donor International 4700, or Topkick box truck to drop this roll back on .
Would be happy to hear any and all advice .

Back in the 70's worked at an old-timer exxon station. He did a top end of an in-line 6, in chassis, that had a terrible ridge on top. Cut it with a ridge-reamer (can you still get them?) and I was amazed how long it lasted for the customer.

Based on that limited 40 yo tale, I say wth, ream it and give it a try....... ??

If it doesn't last, truck looks decent, drop in a junkyard engine?

What would a German mechanic do?

There's your answer Fred..... :)

A lot of force on the rings against the cylinder walls, so I could see hard hits against the ridge. Is there any way to install pistons/rings that come up short of the ridge?

Ball hone or three finger ? A ball hone should smooth that out with a bit more work. I think the one we have in my garage is a 320 grit and it cuts pretty fast. I have used a reamer and it is difficult to get a smooth cut with one.

How does a ridge form in the first place?

Or, why does one form where it forms?

Answer that and it may put your mind at ease.

Yeah, but this is not a german car . You have to come at projects like this from a different angle .:cool:

Hone the poo out of the top and slap it together, drive it another 70k

If it's worth doing it's worth doing properly... So yank it out and drop it off at the machine shop.

I can't imagine it being very expensive to put it right.

Jim Bremmer said it. This is low precision work. Just knock down that ridge. 120 psi is good. You just don't want to break the rings.

This. The ridge forms at the farthest point of the ring's travel. Hone it a bit more, and put it back together

That ridge is why I believe in rev'ing a new motor high before break in and why I hate buying a used car driven softly I want the rods to see full rpm and if they are going to stretch .010 at 6,500 rpm that they need to hit that number daily

If the motor only hits 5k every day and 6 months later hits 6,500 the rings get buggered

A real hillbilly would grind a bevel on the top of the new rings. I recommend reaming it. There's no reason not to make the top of the bore larger, the piston don't care.

My vote is for reaming.

I agree with both of Jim's posts.

What won't work?

Plenty of mechanics will cut the ridge even with the cylinder when doing a simple "ring & bearing" job so as to prevent the new rings from possibly contacting the ridge. In actuality, this should not be a problem because you are not changing the stroke of the piston... the new rings should stop at the same place the old rings did.

If you go for it, all you want to do is eliminate the ridge, making the top of the cylinder match the rest of the cylinder.

The tool is still readily available from places like Summit Racing and this new thing called the internet. They cost about $40 for a cheap one.

Remember - it was the rednecks and hillbillys who were the moonshiners, and who were building the race winning engines when NASCAR was formed.

What everyone else said about the location of the ridge. Why would new rings go where the old rings did not? I'd be more concerned about the measurement of the worn part of the bore just below the ridge vs the OG size @ top of bore. General rule of thumb I've heard is .002 wear per inch of bore in terms of wear/taper before hole needs to be bored.

If that spec works out, just hone the piss out of it and install new rings. I've had great success, (or luck), honing and re-ringing slightly worn cylinders but I am beyond meticulous about cleaning the ring lands on the pistons assembling and breaking in new rings by a specific procedure. Cleaning used pistons is the single most time consuming part of a rebuild for me.

Best of luck.

The shape/cut of the edge of the rings is designed to direct the maximum amount of gasses into the ring land, (behind rings), in order to create cylinder wall pressure and make a good seal. Many people are of the mistaken belief that spring pressure alone creates this seal. Not so.

Filing or camferring(?) the edge of the rings would ruin their design.

Do it properly and you wont regret it!