View Full Version : Got to try out my sunnen hones finally yesterday. Gloat

09-19-2010, 08:42 PM
My father in law given me a sunnen honing set that he inherited from his father. It consisted of 3 sunnen hone tools from 2-6" the biggest is a AN-111. Each set has about 20 different stone sets all from 45-85/87 grit with multiples of each. I've had them for about 5 years now and finally got to use at least one of them yesterday! I used it on the DP on its lowest 240rpm setting and just kept a rhythm back and forth with the feed handle. The block was scored from heat, the bottom two cylinders were the worst. I think oil had something to do with it as well. I had the block punched .020" over 3.187". Got the block backed and checked it (rough bore) and it was 3.195". However their boring left chatter marks on the last 1.5" of each bore so now at least I had some material to work with to get the marks out. I started out with the 45 stones and only had to tighten up the hone 3-4 times got me to 3.205" all around top to bottom each hole. Than I went in with the 65 stones and only tighten up the hone 1 time and the cylinders were at 3.206". Than the same with the 85 stones brought the cylinders up to a final 3.2069". I am real happy how well the hone worked and what a great job it did!

I deburred and smoothed out the ports edges. Cleaned everything up and reassembled with the new pistons. Waiting on a few gaskets and parts yet to finish it up. Tonight I cleaned and assembled the lower unit.




Dr Stan
09-19-2010, 09:01 PM
My first job out of the Navy was working for Superior Hone's Bra-Mar division making custom honing tools. It was generally accepted that Sunnen made better honing tools and Superior's machines were better. You've got some good honing tools to work with.

J Tiers
09-19-2010, 09:46 PM
You'll hate me.....

I TURNED DOWN a big (12 x 12 x 6") box FULL of brand new stones for some flavor of Sunnen hone... about 4 or 5 types in there at least.. Mighta got the box for relatively cheap.

I don't have a machine, and didn't have enough knowledge of what they fit, so...... no sale. I am fairly sure they hit the dumpster about 5 hours ago.

Sunnen being right here in town within long walking distance, you'd think I'd maybe know something about them, but I don't.

Liger Zero
09-19-2010, 10:18 PM
Ok sounds like a good time to ask...

What is a hone? How does it work?

Dr Stan
09-19-2010, 11:12 PM

There's quite a bit of info at Superior's web site http://www.superiorhone.com/index.html. Bottom line it is a method to finish a cylinder (usually a hole) to a fine finish and achieve the desired roundness. Typically used for engine bores, hydraulic cylinders, connecting rods, etc where the hole must be very true to round and quite smooth and/or have a certain cross hatching. If you have ever seen a hydraulic cylinder extended without the rod end connected it will turn slowly as it extends. This is due to the cross hatching in the cylinder. BTW, some companies have started using bearingizing to finish their cylinders instead of honing. These rods do not turn.

One can also think of honing as similar to lapping, but as I said on a cylinder.

I say cylinder instead of hole due to the ability to hone the outside of a cylinder. When I was at Superior Hone I made tooling for the first OD hone made by Superior. It was to finish the OD of torque converters for GM back in 1977 or 78.

BTW, many people confuse honing with glaze breaking and one can buy "hones" at parts houses that are actually glaze breakers. The difference is that a true hone can true up an out-of-round hole where a glaze breaker can only follow the existing hole. If it is egg shaped, tapered, etc it cannot correct the problem, where a hone (when properly used) can straighten out a problem hole.

Hope this helps.


Liger Zero
09-19-2010, 11:28 PM
So it's a very fine grinding process then. Gotcha.

I saw a hone-machine "designed for correcting and repairing extruder barrels" on a used plastic machinery website and was wondering exactly what the process was.

Thank you for the enlightenment Dr. Stan.

09-19-2010, 11:48 PM
Hate to hear about the stones hitting the dumpster what with Xmas right up ahead and all your needy friends here........LOL

The AN is a portable series of Sunnens hones and can bore and finish, don't think you'd want to do a ton of boring with them unless you were Popeye but they will do it......don't those outboards have a blind bore.....heard some of those where a nightmare to accurately finish......very specialized work.......nice job

What DBG were you using?


09-20-2010, 12:08 AM

Generally used terminology says lapping is abrasive machining with a loose abrasive (like valve grinding compound) and honing uses a solid abrasive stone. Lapping can be flat surfaces or cylindrical, ID or OD. Honing, by machine anyway, is usually working with cylinders. I suppose you could include knife sharpening as in honing an edge, but for machinist purposes there usually needs to be some means to set tool position which then controls size. You notice VPT mentions adjusting or setting his hones. Within limits, the hone will abrasively cut out to a certain size and then stop cutting unless adjusted outward more. That's oversimplified somewhat since stones will wear etc. but conceptually it gets you in the ballpark.

There was a process developed 20 or 30 years ago by a company they called Extrude Hone. It pushed an abrasive putty-like stuff through a passageway to polish the interior of a possibly convoluted hole that couldn't be accessed otherwise. Calling it honing might be stretching the term since you couldn't control size and shape except by quitting at the right time.

Liger Zero
09-20-2010, 12:15 AM
The machine I was looking at holds the extruder barrel in position and feeds what I know know is a grinding tool down the length of the barrel.

It's a custom build machine, obviously designed for a company with BIG extrusion lines. Pretty cool device now that I know how it works.

Makes sense now that I think about it, an extruder barrel can get scored by metal chips in the material stream or suffer uneven wear due to processing conditions. You'd put the stone in there adjust it "just so" and grind out the problem... returning said barrel to a smooth-and-round condition.

Very cool stuff. :)

09-20-2010, 08:10 AM
Hate to hear about the stones hitting the dumpster what with Xmas right up ahead and all your needy friends here........LOL

The AN is a portable series of Sunnens hones and can bore and finish, don't think you'd want to do a ton of boring with them unless you were Popeye but they will do it......don't those outboards have a blind bore.....heard some of those where a nightmare to accurately finish......very specialized work.......nice job

What DBG were you using?


I would have gladly taken those stones off J Tiers hands! If there was even one diamond stone set in the whole box that was worth $100 by itself.

Yes this evinrude block has blind bores. I set up the depth and retraction stop on the DP so I wouldn't bottom out the hone and I wouldn't pull it out of the bore to far. I had a total of about 2" stroke.

DBG? Bore gauge, deburring tool?

09-20-2010, 05:25 PM
Yes those blind bores definately add another challenge to the job.........well done for a first effort. Did you prefer the DP to a portable hand drill? Guess with the bottoming stop it was the perfect setup for this job.

Just wondering if you used a dial bore guage and what brand? Would think you had to and maybe it also came with the tool lotto..........LOL

09-20-2010, 07:44 PM
Yes in fact I got a whole drawer full of micrometers, dial indicators, calipers, bore gauges, you name it. All older but good brand stuff that works excellent! My Father in laws Dad was a machinist and diesel mechanic. I could fill a whole page with tools that he gave to me, it was one of the happiest days of my life!

Anyhow I was using a snap gauge and than checking with a dial caliper. The measurements I was getting were repeatable over and over again. It seamed very accurate.

I didn't look at the snap gauge just grabbed it and used it. Most of the stuff I noticed is century so it may have been a century snap gauge?

I liked the DP over a hand held drill because like you mentioned the big reason is I could adjust stops. Other reason I figured it would be better to have a constant rpm and I felt like I could get a better job with the bore and spindle aligned. I do wish that my DP had a lower speed so I could have gotten a little more aggressive cross hatch. Maybe some day I will look into doing some pulley mods to get another lower speed option.

I will get some pics of the cylinders when the gaskets come in and I install the head gasket and such.

09-24-2010, 08:31 PM
Got it all together today and had it running for just a few seconds. I couldn't get spark and traced it to the power pack. It started and ran with the power pack from the work boats 70hp evinrude. When I get the new power pack I will be able to take the boat out and adjust everything and run it on the river for a few hours.

I put in a extra set of pullies in the drill press and I feel I still need a lower speed for honing. I think around 60rpm would be good, with the extra pullies it looks as though it is only down to 180rpm.





09-25-2010, 10:53 AM
Nice job...........sounds like a VFD would work out nice on the DP.

Different stones reqd for working in aluminum?

09-25-2010, 07:56 PM
The block is aluminum but there are steel sleeves in this block. I believe I did read something in the hone instructions about stones for aluminum but I didn't read much about that.

Yes a VFD would be nice on the drill press but this is realy the first time I ran into a problem with the speed on this DP. I put in a couple extra pullies like I said but it isn't slow enough. I have more pullies I can try but then I wouldn't be able to shut the belt cover because the pullies would be to big.

10-05-2010, 08:43 PM
New power pack showed up today and installed. Motor runs beautiful with just a water hose hooked up. Can't wait to get it on the water tomorrow!

10-07-2010, 08:48 AM
Ran an entire 6 gallon tank of gas threw the motor yesterday on the river following OMC's break in procedure. Motor ran great the whole time! No funny noises, no loading up, no misses, just ran like it should.

However with the old 40hp motor every now and then at random times the no oil warning buzzer would sound. You would pump the oil primer bulb once and it would stop and no problems until the next time. Does the exact same thing with this motor. I have had the oil pickup tube out of the tank before to check for blockage and everything was fine. I always thought it was the motor/VRO pump in the 40 but now with the 60 its the same deal. The only thing I can think of is the oil sensor in the tank isn't reading right. But the no oil warning sensor is on the VRO on the motor itself. Only the low oil warning sensor is in the tank and that is a different buzzer sound than what I am getting.

Any outboard gurus in here have an idea what is going on?

10-07-2010, 09:57 AM
I don't consider myself an outboard guru, but here goes anyway.

Sounds to me like the pump is malfunctioning on the oil injection reservoir.

I would be very hesitant to run it until I had it figured out.

Did the cylinders go bad from no oil?

Maybe you could find a loaner oil injection reservoir and see if the buzzer quits beeping.

That is too much work to have to do it a second time.

Call a local marina and ask them. They generally have real guru's there.

Good luck and keep us posted.


10-07-2010, 06:28 PM
I have been running a mix in the gas (OMC recomended) just in case the oil injection is not working.

The oil pump is bolted to the motor and is a different one than the old one on the 40hp. The only thing in the reservior is a pick up tube and a low oil sensor.

The new motor originaly scored the cylinders and pistons from heat. When I was looking into the motor I found more than a few water passages blocked by casting which I removed. I realy don't think a lack of oil was an issue.

I just find it very strange that the same exact thing happens with two completely different motors and oil pumps. A new VRO/oil pump is 250-350 bux.