Wondering wheather or not to hone the liners with the pistons in or not hone . I am not pulling the sump and pistons-too much work and not enough time . The head is off and the hone lines are very faint , places not visable . Very big hours but good compression and only moderate blow . I dont expect it to last for ever but another 4 to 5 k would be nice. No wear ridge and about .02mm wore off bore . Would honing what I can be of benefit or not and then there is a danger of a little grit that will end up in the oil .
I don’t think I would. What would you gain by honing basically half the cylinder? What engine is it and why is it apart?
No sir'ie BoB--------------------------Don't do that, leave it be.----------------------other wise it will be eating oil like **** through a goose.
I agree, I don't think it's necessary because as Mike L stated you won't be honing the bore where the piston rings are when the piston is at the bottom of the stroke. But if I were to do it I'd probable cut a round piece of cardboard to sit on top of the pistons and hit the bore a few strokes with a dingleberry hone just to knock the glaze off of the exposed cylinder wall.
You have dingleberries you old scissorbill? Ha ha.
Well of course...I'm loaded with balls.
Not trying to sound like an @$$hole, but have you ever worked on an engine before?
Any grit from stone or bead type hone will make it's way down to the top ring land, in order to properly hone it the beads require a lite cutting fluid which will run, can't be helped. Not my engine so do what you want.
And he even has a special hone for them!!!
I don't know why folks are getting their knickers in a wad here about honing the bores. First of all Volvomad clearly stated the engine has "very big hours" on it, so we're not talking about a machine shop rebuild, just getting all the life he can out of the engine before it does need rebuild. Second, what is the purpose of honing a cylinder? Plain and simple, it has nothing to do with compression or sealing of the rings to create compression, it's for lubrication of the rings/pistons. The crosshatch scores of honing creates tiny valleys to retain oil for lubrication of the pistons and rings as they move up and down. Over time, the rings "polish" the cylinder bore and effectively erases these crosshatch lubrication scores, what's known as "glazing" of the cylinder. This "will" accelerate wear of rings and pistons because lubrication is insufficient. So, in a pinch, I don't see the harm in using a dingleberry hone to "de-glaze" the bore. Yes, honing debris will be generated during the process. Some brake cleaner and compressed air will blow out the bulk of it, and so what if there's a little left over, it's a "very big hours" engine. What's left will be burnt off quickly when the engine fires off and will be of little consequence on this engine. Give the bores a quick crosshatch with a flex hone, blow it clean with brake cleaner and air, put bit of oil around the piston to lube it on start up, button it up and let if fly. jmho
I normally highly respect your responses, Willie, but I have to point something out here: Based on his comments, why on Earth would a guy even consider honing? "Good compression and moderate blow-by". Sounds like he needs to clean the deck good, button the damn thing up and get it back to work. IMHO, of course.
I appreciate that Shimmy1, my hat's off to you as well. But again, crosshatch scores from honing are for lubrication, has no relation to compression seal. If he has good compression then there's still life in those cylinders. But if his cylinders are glazed then the pistons and rings will suffer from poor lubrication from lack of scores to trap oil increasing wear. That's all the hone scores are for, lubricating the pistons and rings. If they're glazed, I'd hit them with a flex hone to get some scratches back on those bores and wrap it up.
I've done that to a few engines (read old beaters that we're still gonna milk hours out of), ball hone, penetrating oil, blast everything out with a solvent blower or sure shot and brake clean at the end. It does the intended job, not pretty but effective in a pinch.
Hone it, Hone the hell out of it, then hone it some more.
I have replaced one or more pistons in a engine and never honed them alot of times. I have ringed more than one engine and didnt hone them. None of them used alot of oil and the ones i keep track of lasted ok. I did this because most still had their crank shafts in place and i didnt want think i could ever get them clean. So theres no way i would do it.
It seems like I did this one time way back in the day. I dont remember the exact circumstances as to why I did it but I do remember placing a paper towel around the piston edges to catch lube oil run off. I used a crosshatch hone and hit the bore a bit to deglaze then cleaned the bore with brake cleaner and air. You already have a well worn engine it sounds like that you just want to get by a bit longer so I dont see that you have anything to lose. Just dont hone the **** out of it. just a simple rough up should do. One of 2 things will happen.......... 1. It will be successful and you get that extra run time you desire. 2. It wont work, eat oil, you have to pull and rebuild it anyway..........and you can get all the free advise here you need as we try to set a new repair record of 65+ pages! .
I never ment to start a war, just looking for a few opinions . I have ripped an engine before . I have honed this engine about 4000 hours ago when it got a set of rings . The cross hatching was gone very faint especially halfway down the bores that time and now it is slightly fainter now . I was thinking a quick,bad hone was better than none . I would still get the most worn area . It is a water cooled deutz 6 pot . The head is off for valve rebuild as the oil is running down the stems after 26000 hours . I have left the oil in it as I normally would when doing top work and will drain after 1 hour running to get rid of any debris . Thanks willie for not slating me and I like the cardboard idea.
This isnt a war, just a dust off. You will know its war when FWF starts laying the GIFS down That guy is nothing but trouble!
I think it is not a bad read anyway. Must be my forth or fifth thread on this engine so we might make 65 pages all in . It amazes me as to how long first day hone patterns last. The engine is in a Volvo L90e shovel .If I was to pull the engine it would probably cost 4 to 8 k to bore and the hole shebang as deutz parts are very dear anywhere I look . and then lob it back in front of a clapped out transmission .Or pull both out and spend god knows . The machine as a whole is running very well so I would like to kick the can down the road another bit . Only currently running 500-700 hours so 2 or 3K would go along way .
i was taught that the crosshatch is for ring seating and break-in. if it doesn't burn much oil i wouldn't touch the cylinders. don't try to fix what ain't broke. just my opinion
This is what I was taught as well. I couldn't be forced to hone cylinders with the pistons still in, much less having worn rings sliding up and down a fresh hone job. 26,000 hours I would say that engine has given everything that could ever have been expected to give. Sidenote: Why didn't it get a new head (or at least a rebuild) 4000 hours ago when you re-ringed it? 22,000 hours on a head is pretty good? I've also been taught that if you don't service the head after freshening up cylinders you are asking for oil consumption? Just a thought...
I really should have done the head back then but the valves seemed pretty snug in the guides ,it was doing only 300 ish hours a year after the bubble burst . It was slugging oil at the time because the oil rings were shot. I replaced the big end shells and pulled a main which looked very good . I couldnt have torqued some of them with the engine in so I left them all alone. I always thought the cross hatch was important for engine life (like willie said) ,not just for break in ,but I wouldnt be stripping engines too often ,nor did I learn alot in school about honing . Hence the question
I like a good multi page discussion on how and why and what for
Just to clarify, as concerning "honing" cylinders on new liners, which is the norm, it's actually a process to address two things, 1) to make (as perfect as possible) a perfectly straight bore and perfectly round bore for proper clearance of both pistons and rings, and 2) to provide "crosshatch" scores (peaks/valleys) in the bore to trap oil in the valleys for lubrication, which does assist in "breaking in" new piston rings since with a perfectly slick bore, as the piston moved down, the lower oil ring would simply wipe the oil from the liner thereby not allowing any oil to lubricate the top piston rings, oil is trapped in the valleys of the scores to allow lubrication of the top rings during break in and for many hours after until the rings "polish" the bore removing the valleys, which is actually normal as an engine wears and grows closer to time for rebuild/replacement. All this relates to a new or fresh rebuild engine. But in this topic we're referring to an old, many hours, yet still good engine, solid compression, which is an essential component of the triad for a diesel to run, that is, fuel, air, compression, a lack of any of those three and it's no go. In this case, all I'm suggesting, is not to "hone" the cylinders, that's not necessary and would likely not achieve much as things are currently "worn in", no, all I'm suggesting is to put some crosshatch scores in a glazed cylinder to assist with further lubrication of the rings as it goes on down the road, nothing more.
Volvo-Deutz D6&7 engines have ridiculously thin liners to begin with. What cavitation hasn't eaten away , you wanna scratch away? Like most have advised, clean the deck and let her rip. Make sure you have the correct head gasket for liner protrusion. Honing is sloppy work when done right. Lots of cutting oil and a tri-stone slinging oil everywhere, for what? No gain to be had. Good luck in whatever you choose. No liner should ever be honed in the first place. If the cross-hatch is gone from the ID, the lower o-rings are toast and cavitation has eaten the top OD below the fire ring. It's a waste of time and effort.
As far as I can see ,it is a mono block . They have different head gaskets alright .The last time I honed it was with a tri-stone (I never heard of flexi hones till now ) and I used a fairly slow drill ,went up and down vigorously for 6 to 8 seconds . While I am waiting for the head ,I will clean it up ( I just took off the big stuff and let it soak and went at other crap ) and have a closer look . I dont think a camera will pick it up properly .
On clean up it has dry liners ant there is still a faint to very faint cross hatch on all I can see ,so maybe that is enough . I do like the look of the dingle berrys