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Discussion Starter #1
Hey guys, this is for my 7MGTE but I've gotten some great advice from the Mk2 guys before so I thought I'd ask again here.

I have a low milage shotblock with blown rings, I have some cast rings for replacment and am ready too go.

As far as I understand, I need too get a ball hone on the drill and try too get a 60deg cross hatch pattern going on too deglaze the cylinders. Then get my rings on the pistons, and slide them into the bores. I've got a 9.6 Black and decker and a 5 amp Makita, what kind of rpm should I be using? how fast do I move the hone up and down?

Any advice on honeing and ring replacment from somepeople who've done it before? It would be greatly appreciated.
 

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what I do when I hone my blocks is that I put WD40 on it and put the drill at a slow speed and go up and down slowly nothing too fast. Sorry I suck at explaining things :(

but HTH's

zankone
 

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If you can imagine the drill on the slowest setting it will go before it just stops, like its slowly revolving, like a hypnotist spinning a watch, and at the same time, going up and down very slowly. Picture a single point on one stone moving as if being threaded into the block all the way down and then back up again at the same pitch. I've noted some power drills won't even go slow enough for me but the rechargable ones that double as screwdrivers work pretty well for this. Hopefully thats a little more descriptive.

Phil D.
 

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I'll leave the honing to a professional when I get my block done. A bad hone & crosshatch can mean significant HP losses.
 

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Discussion Starter #5
If you can imagine the drill on the slowest setting it will go before it just stops, like its slowly revolving, like a hypnotist spinning a watch, and at the same time, going up and down very slowly. Picture a single point on one stone moving as if being threaded into the block all the way down and then back up again at the same pitch.
Ahhh! that clarifies things, my little cordless can go really slow, like so slow I can actually move it and track the stones on their little journey.


I'll leave the honing to a professional when I get my block done. A bad hone & crosshatch can mean significant HP losses.
A good idea, not for me, I'd never screw stuff up and learn anything if I didn't ;)
 

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Do you have an automotive machine shop in your area? If so, stop by and see if they have a Sunnen CK-10 machine. Watch the machine while it's in action and that'll show you what all is involved in honing the cylinders. The 60 deg. crosshatch pattern is a must since that provides the proper "plateau" (raised metal) for the rings to seat against. I used a cheap variable speed drill the last time I honed some cylinders and burned out the trigger trying to keep the drill running at a slow enough speed. :roll: Using a cordless screwdriver with enough RPM sounds like an excellent idea! Plenty of torque and consistent speed! I use lots of honing oil and a 3-stone hone, but I prefer using a 4 arm (2-stone & 2-wiper) type hone. What type of rings are you using? I use a 280 grit stone for moly rings and a 400 grit stone for chrome rings. Honing cylinders is somewhat of an art and requires some patience and skill. Try practice honing one or two cylinders on a block that you don't plan to use right away first so you can get the feel and alleviate any fears that you might have of the whole process. HTH!
 

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I work at a Toyot dealership and I recomend using a ball hone and coating the walls and the entire hone in ATF or and high performance oil. I like using ATF it seam to work the best. I use a Air drill wich i can adjust the RPMs and i wont do over 15 pumps per cyl.

im use this method on just about every toyota motor i have rebuilt. never had one problem with rings. I dont like the stone hones be when ur doing it by hand the stones have a habit of rocking in the bore.

Just my 2 cents
 

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Discussion Starter #8
Do you have an automotive machine shop in your area? If so, stop by and see if they have a Sunnen CK-10 machine. Watch the machine while it's in action and that'll show you what all is involved in honing the cylinders. The 60 deg. crosshatch pattern is a must since that provides the proper "plateau" (raised metal) for the rings to seat against. I used a cheap variable speed drill the last time I honed some cylinders and burned out the trigger trying to keep the drill running at a slow enough speed. Using a cordless screwdriver with enough RPM sounds like an excellent idea! Plenty of torque and consistent speed! I use lots of honing oil and a 3-stone hone, but I prefer using a 4 arm (2-stone & 2-wiper) type hone. What type of rings are you using? I use a 280 grit stone for moly rings and a 400 grit stone for chrome rings. Honing cylinders is somewhat of an art and requires some patience and skill.
We BARLEY have a proper auto machine shop around here, I doubt they'd have a real machine too do it.

I'm using normal Cast rings, I'm not sure what grit stone I should be using for this, and getting the right 60deg crosshatch seems difficult, I really don't wanna screw this up.

I work at a Toyot dealership and I recomend using a ball hone and coating the walls and the entire hone in ATF or and high performance oil. I like using ATF it seam to work the best. I use a Air drill wich i can adjust the RPMs and i wont do over 15 pumps per cyl.

im use this method on just about every toyota motor i have rebuilt. never had one problem with rings. I dont like the stone hones be when ur doing it by hand the stones have a habit of rocking in the bore.
Ball hone I heard was the easier way too do it, do they come in different grits too? Using ATF sounds easy enough, nice and slippery stuff. I'm worried I'm not going too get the pattern properly, is this over my head? I don't really want too pay a machine shop too do it, but I'm getting a little worried.
 

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i dont know if i would use cast rings. the 7mgte uses chromoly rings from the factory. replacement chromoly rings run ~$70 a set from most parts stores. sometimes the machineshops can get them even cheaper.
william
 

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Discussion Starter #10
i dont know if i would use cast rings. the 7mgte uses chromoly rings from the factory. replacement chromoly rings run ~$70 a set from most parts stores. sometimes the machineshops can get them even cheaper.
Uh oh, I didn't wanna know that. The cast were 75$ Can, the moly were double that. I hope they work!
 

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sorry, the prices i listed were in usd. didnt realize you were in canada. but yeah, stock rings for a 7mgte are chromoly, rings for the 7mge i beleive are cast. i guess depending on how much boost you run is to how well they will hold up.
william
 

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Chromoly rings are more durable than standard iron rings and will hold up better under the higher cylinder/combustion pressures and the additional combustion heat that the 7MGTE produces during boost conditions. I would say that if Toyota recommends the Moly rings then you're best to stick with them for durability sake. Check and see if Sealed Power manufactures a Moly ring set for the 7MGTE. Preferably the "Speed-Pro" series rings (if they still make them). Those are hard to beat. Flexible ball hones are more forgiving and much easier to use if you've never used, or just simply don't like fixed stone type hones. The ball hones can also more adequately deglaze a worn cylinder that has any taper or is slightly out of round from wear. Flex hones are available in different grits. Try using a 280 grit flex hone for a set of Chromoly rings and a 240 grit flex hone for iron rings. Just be sure to use plenty of lubricating oil to prevent the stones from running dry. Also, don't forget to check the ring end gaps and the piston groove (ring land) clearance before you install the pistons, and be sure to position the gap openings in the proper areas around the circumference of the pistons.
HTH!
 

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I hope my rambling on this topic hasn't changed your mind on honing the cylinders yourself. There's a first time for everything. Give it a whirl. :)
 

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Discussion Starter #14
Posted: Wed Sep 24, 2003 5:19 pm Post subject:

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Chromoly rings are more durable than standard iron rings and will hold up better under the higher cylinder/combustion pressures and the additional combustion heat that the 7MGTE produces during boost conditions. I would say that if Toyota recommends the Moly rings then you're best to stick with them for durability sake. Check and see if Sealed Power manufactures a Moly ring set for the 7MGTE. Preferably the "Speed-Pro" series rings (if they still make them). Those are hard to beat. Flexible ball hones are more forgiving and much easier to use if you've never used, or just simply don't like fixed stone type hones. The ball hones can also more adequately deglaze a worn cylinder that has any taper or is slightly out of round from wear. Flex hones are available in different grits. Try using a 280 grit flex hone for a set of Chromoly rings and a 240 grit flex hone for iron rings. Just be sure to use plenty of lubricating oil to prevent the stones from running dry. Also, don't forget to check the ring end gaps and the piston groove (ring land) clearance before you install the pistons, and be sure to position the gap openings in the proper areas around the circumference of the pistons.
Moly eh? Uh oh! I'm gonna blow some stuff up, the rings I have are Cast from Hastings, I've been running 14psi on the stock CT on my old block, I hope these rings will be able too handle it, I don't have plans on going past this level, just selling the car next year. If they use them on the 7MGE, 6M, 5M and those guys run boost, hopefully they'll be fine.

Ok! 240grit ball hone, I can handle getting one of those, and checking clearences won't be a problem, I'll be sure too do em all.


I hope my rambling on this topic hasn't changed your mind on honing the cylinders yourself. There's a first time for everything. Give it a whirl.
I was getting a little scared there :shock: but am feeling better now! Thanks a ton for the advice! I'll let you know how she goes.
 

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Have fun and do let us know the outcome of your endeavors. You brought up a good point when you mentioned that some 5M, 6M, etc. owners could possibly be running the stock rings on their turbo engines that were used when the engine was NA. This would make a good topic, but I've probably said enough already. I've heard one or two comments in the past about what material(s) the factory piston rings are made from, but nothing in concrete. I personally don't know the exact answer to this myself but would like to know. Japanese metalurgy is a science in a class by itself, so the actual piston ring materials used from the factory may be an unsolved mystery, at least for some of us.
 

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Discussion Starter #16
http://www.angelfire.com/biz/snwvlly/bikes/dnthone.htm

This basically states that when using cast rings (like me) you don't need too "de-glaze" cylinder because they aren't really glazed and that if I put in cast I don't need too hone the cylinder.

Hee hee its funny how he compares cast rings too basically "lubricant" compared too moly.

Anybody got thoughts on this?
 

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Discussion Starter #19
Better yet, try this link. You will have to download the 5-page article but it's good reading.
Ahhh a good read, of course now I'm MORE confused! AHHHHHHHH!!

One thing I have too ask, is do I have too pull the crank out too do the honeing? I'm gonna get nasty metal bits and stone all over my pretty crank and blow stuff up if I don't?

Since I can't get a ball hone, I guess I'll get a 220grit 3-Jaw and attempt too get the crosshatch.

Thanks for all the help Dave, I really appreciate it.
 

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Oh, I thought maybe you were rebuilding your complete engine. My bad! Yes, it is best to remove the crankshaft when honing the cylinders so the fine grit doesn't find it's way into the crank bearings. Just be sure to thoroughly scrub the cylinders and the areas below the cylinders when you finish honing. A toilet brush with some dish soap and hot water works like a charm. :lol:
 
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