Pulling apart my first flathead (eurpoean 21 stud) Whats the deal with bore wear? They all look good apart from the sump side of the front 2 cylinders which both have a bit of a step at the top of the bore. The inlet side is fine though. Are these two cylinders more prone to wear? How much step is too much? This is hopefully a quick cheap rebuild, more to learn than anything else. It may never see a car but it might do eventually so dont want to cut to many corners.
The front two cylinders stay cooler from the water pumps directing coolant from the radiator right into the cylinder wall. The cylinder is hot on one side, cool on the other, and out of round when at operating temp. It's a problem with the in-lines too. How much is to much? How much do you have? Do you plan on replacing the pistons and rings? Jeff
Not sure about piston/ring replacement. From the little i can see/guess/assume they are probably ok. Wont really be able to tell untill there out. As for how much step is there, hard to say as i havent tried to measure, you can feel it though, maybe the thickness of a piece of normal paper. No other lines/scoring or marks in any bore, no other steping apart from the bottom part of the front 2 bores.
Hard to tell you what to do. I would pull the pistons and measure the cylinders. You never know how bad they are until you do. Ridge can be a false indicator for cylinder wear. Someone may have ridge reamed the block at one time. The problem you end up having leaving the ridge is it likes to break the top ring. You put new rings in and they hit the ridge and many times break. You really need to measure the bore before you can decide what to do. If you push the pistons out and the rings look good(not stuck or broke) You could put them right back in and try it if the bore measures good. It's chancy, but if it all looks good and freash you could roll the dice..... Jeff Ps. You have an Anglia? I have a 50-51 for a future project
We did pistons & rings on an 8BA that had a little wear, a small ridge and a little taper wear.......we thought we were going to get away without boring it. Less than 1000 miles it was missing and had a bunch of blow-by. Yep, damn thing broke half the rings and we ended up boring it anyway.......and another set of pistons & rings. Get those bore mikes out and measure, measure, measure first.
Pretty much as i thought. If it needs rings rebore it, if it needs rebore fit new rings. If it all measures ok when its fully stripped and the rings look good ill put it back together as is. Thanks folks. Oh, and yeah, i have an anglia, a 1949, 10hp engine, 8hp head, aquaplane manifolds, twin su's. Just bought a ballamy IFS axle for it. Got plent of plans, plans that may end with this very engine
STOP ! Before removing pistons anytime there is a ridge you MUST remove it . If you don't you chance breaking rings and the piston also. Never put new rings in a bore the has a step/ridge ,broken rings and or pistons follow. The tool required is a "Ring ridge remover". Using a old ring and feeler gauges measure the ring gap at the bottom of the cylinder below ring travel and again at the top just under where the ridge was. Devide the difference in the gauge thickness by 3 and that will give a real close idea of the taper. Use a piston to push the ring in the cylinder so it is square. .010 or less taper is a good canidate for re-ringing with the old pistons.
Actually after consulting a few engine guys......one on here who I RESPECT a bunch, many say not to use a ridge reamer anymore.Does more damage to the tops of the walls than good.
Yep. Bored quite a few blocks anouther .030, and had to sleeve a couple, because of the ridge reamer...
Like any other tool, ya gotta know what you're doing when running a ridge reamer. They work great if you use them right. A common error is to keep cranking them around after the cutter reaches the top of the bore. That can result in a tapered cylinder for the last 1/2" or so, a big no-no. If you don't cut the ridge, how do you get rid of it? The pistons will break lands, rings will break, and how do you hone the walls with the ridge still there?
You bore it. That's the best way to get the ridge out. I would pull my hair out when people brought blocks in to be bored, and they used a ridge reamer to get the pistons out. I'm not saying this is what you are proposing but that was my bitch. I agree you need to get rid of the ridge if you replace the rings. I've done some rering jobs with a guy that had a repair shop. He would tell me "hone the block untill it is round, I don't care how much you take out". I would hone the cylinders to .003-.005 max out of round (they would all have taper)and by that time the ridge was trimmed down, not gone, but blended. Then he would have me put a heavy knurl on the pistons. He would then fit the pistons by filing the knurl down untill they had a little drag. He would alway say you were better off with the cylinders being big, and having a little extra ring gap, then having the cylinder out of round. He had good luck. The old boy died a few years ago. I liked him. Jeff
all the engines i take apart are so fucking old and worn out the only question is bore it .030 or bore it .060? wanna buy a ridge reamer and a cylinder bore gauge?
Ya know the old saying Ya can f^^k up a wet dream !! If the intention is to bore it beat the snot out of the old pistons 'cuze it don't matter. But a lot of engines can give a lot more service with a re-ring . So ya got to get the ridge out. In the last 50 years I've used quite a few different reamers and with some it was easy to screw up the cylinders if ya didn't know how to use it. I've had a "Lisle" for the last 30 years for my own ,pretty idiot prouf.
I have to say I'm with John. Built a lot of motors in the late 50's early 60's when I was a kid. We didn't have the "big bucks" to have motors bored/new pistons............etc. We would take motors with .010 taper in the bore and knurl the pistons and put oversize cast rings in them........................only after we used a ridge reamer to get the ridge. Yes, you have to be careful and work slowly because it doesn't take very much to go past the ridge. Built some pretty stout 6 cyld Chevys that would outrun those new 265 Chevy V8's and never had a problem.......................If you are going to re-ring the motor you have to use the ridge reamer to get take out the ridge before you put new rings in the motor. IMHO
People are probably going to laugh at this, but I have used a bearing scraper to blend out ridges. Cheaper than a ridge remover, and has infinite control. And man did I give that engine a hiding afterwards
Thanks, all good info here. I should be doing more stripping down tomorrow so ill probably have some more questions.
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