acceptable cylinder wall scoring 2 stroke

Login, Boats Otherwise, if it's acceptable, then I'll run with it and save up for two rebuilds on both of my motors. Waxes, Boat Cleaning Is the engine two or four stroke. So frankly I don't believe your compression tester. Helm Seats, Shop Take meausurements of the piston ring's end gap using a feeler gauge at three or four locations from top to bottom. If your cylinder is scratched lightly it's still runnable (provided compression is good), but still very disappointing for you. PFDs, Roof Racks, Carriers, That means Bore job, oversized pistons & rings, etc. Is the engine air or water cooled. Oil ring is about 0.02 to 0.035". Oars, Wakeboard, Wakesurf & I have not had good luck doing top ends. After googling it online lots of others had previously seen the same thing. Yeah you're right. Looks like metal coming up from the bottom end. But leave the rest in place. Just slap the head back on and enjoy your truck. Reason - If the piston to cylinder clearance is too large it allows the piston to rattle inside the cylinder bore, with time the piston develops stress fractures and eventually cracks. It says .50 on the piston. Step 1- Get on the phone with who you bought it from. Your link has been automatically embedded. PuKerogen itself is usually formed from algae and other marine plant life. It was supposedly rebuild like less than 20k ago. Make sure they are not hurt and that the rings do not bind anywhere. 11 GT Black, A6,Steeda CAI, SCT X4, Circle D 4C. Run it. But on very close inspection the machining grooves in the piston are not worn down. When it is desired to repair, or fill in the score 1 of a cylinder wall 2, the score 1 is first thoroughly cleansed free from all oil, and foreign matter. This is only based on your compression testing, a thing I've never done in all our years of 2T ownership, but appears to be the deal in the US - have you given the new rings long enough to bed in to a new cylinder and are they mounted the correct way up (as they are keystones). If your machinist bored to exactly 85.5mm (and if he was a good machinist) added some clearance for the piston, you still might have gotten pistons that were ever so slightly over size (tight) or under size (loose). so i think im going to start investigating and see what went wrong. Pic three is a good example because way up in the upper left the scuffs end just below the port (rings?). I just ran it till something was not felling right no more. Millennium or powerseal are your best options. I just paid. Anchor Box Anchors, Fishing Rod & Reel scored cylinder wall 2 stroke By Oct 29, 2022 . Metal bits leave a big groove that will not clear with time. In some other thread, I see where you have a manual. 23sfHdDD$gAPH$9g "*Y (9={=U}U;M*!P.Bl\qq>Aa>.^^=LP The fuel to oil mixture is also known as a premix. Boat Repair, Boat Paint & If it's just that one little spot, I wouldn't sweat it. Pumps, Livewell Aerator Pumps Boat, Boat Buyers W-k~3}T]x}e']%=+^JqjoJ{&,uqZSY7N|vtl{jI1Vl T5'V9C0dDkDGz1YFq'lP=pxt;6Wk/*B3dSU&2enH#)%6@a: Good photosshow way too much detail . It may not display this or other websites correctly. Accessories, Electronic Navigation So I did the timing. Even honing may remove too much material. By continuing to browse our site you agree to our use of data and cookies. 2009-06-28T02:31. . Heat cycles are for gasket baking and leak testing, not break-in. like an inch from top to bottom. You can post now and register later. I wouldturn my attention to the Ring Scuffs. But that's just me of course. The picture doesn't show well, but both edges are deep enough to catch my fingernail in. Deals, Pumps & Plumbing When you buy through links on our site, we may earn an affiliate commission. and 70 psi you would have a hell of a time starting it.if at all. That little scratch shouldn't be making your engine run badly. first 16:1 is way to much oil even 20:1 is to much imo,32:1 is much better suited to these engines.the cylinder shown is still in good shape though it does have some issues of not being truly round as is evident by the wear pattern.there is a long inverted funnel shape wear pattern above the transfer bridge that the top of the bridge is causing Sleeving will screw up your porting and sleeves have a tendency to overheat. And ring tryihng to expand into it is going to make it work in and out of the ring lands wearing out the piston. Towers, Tow Ropes & %( & %(n.*]Pn;G? Power Seal. Tear down showed the aluminum bore scored up bad, piston in bad shape too. Can I install bigger pistons and new rings? Does anyone have the torque specs for the head nuts and the 4 cylinder nuts? Tops, Bimini Top JavaScript is disabled. Either it's camera artifacts or they used a concrete block. The increase in power of the engines has necessitated using liners of greater wall thickness. I hate to be that guy, but if you have another vehicle to drive I'd park that thing until you can afford to fix it right. Lightning, Harley-Davidson F-150, Roush F-150 & Saleen F-150, Conventional (Bumper Pull) Towing; Travel Trailers & Pop-ups, Toy Hauler Towing; Fifth Wheel & Bumper Pull, Flatbed, Car, Boat, Utility, Horse & Misc. I will use a little more brake clean and run a razor over everything again before actually putting in the gasket, but I think it's pretty clean now: The following errors occurred with your submission. The stock cylinder is not steel or iron. Again its amazing what the camera sees. J_Watson Posted May 29, 2012 KDXGarage Posted May 29, 2012 My Ride Posted May 29, 2012 Two-strokes are great and they can tell you when they need to be refreshed based on performance! & Live Bait Savers, Boat Trailer Guides & July 23, 2010 in Engine. Pulled the heads for an AFR swap and felt this when wiping the cylinder walls with a fresh oiled rag. If it's hard (or just as hard) to start when hot, then it may be a sign that you need a new top-end. Covers, Boat Seat <> The stones are then changed to #600 grit diamond stones and honed at 20% load for four strokes. Please register or login to enable Dark Mode. It's an easy mistake to make, and your symptoms sound like a PV issue to me. 1,025 what causes cylinder wall scoring? millennium told me it was because I didn;t use assembly lube. Zincs, Generator Then Soap and water. If you can snag a nail on that nasty one in pic one (intake side??) Continuous operation at WOT dramatically increases the thermal loading of the piston, causing it to expand more. xwP} When the oil film on a cylinder is momentarily burned or brushed away, the metal surfaces of the piston and the cylinder wall will actually touch. z.@O.%iy'kJr=Irn$=_b&]`i{Y'xQ!R>^nL6t[f%{g-RUh/(lDQ])*\2u$E^1jprkn%oZ[764n-l>DzO3_s8D+5j/B";X{P^! The majority of cylinder wall scoring will leave marks on the engine and piston rings. Like Moose said sleeving is far outdated. Here's the whole wiki info Sappers copied and pasted: Look on www.finishing.com if you want more info. As long as the head is off, just drop the pan, remove the cap, and push the pistons out. As I've gotten older, I now actually get my son (or someone younger) to visually check it for me. Flush your crank with a Gas oil mixture, into a cleanwhite pail and check for debris(then re-lube bearings mains and rod)Measure piston to cylinder and put new rings (check gap) and monitor your engine. What is the mark in the top of the piston? Cause - Piston to cylinder clearance too large or engine over-revved. Cant I just sand paper that glaze out? dirtbiker4life96, If it bubbles, you are through to the aluminum and time to renick. AN Blast it clean in the sink under high volume of water and good pressure. Light scuff can be honed if cylinder is within wear spec's which most inlines are not. This is generally ok and can be ignored Check ring end gap and clean, clean, clean and then lube (Hope ring end gap is ok, cause filing by hand, modern rings that may have a surface coatings can be another cause for scuffs) . Caused by metal to metal contact, which is common on 2-strokes when they aren ' t warmed properly! 4) By avoiding ingress of moisture from the charge air. He swears by PowerSeal. First, warm up the engine, so the rings have a chance to seal. Muriatic acid will take aluminum off the coating (and remove cylinder material, so be careful!). The cylinder liners used in modern marine two-stroke engines are cast from a cast iron based alloy of chromium, molybdenum, and vanadium to increase the wear characteristics. Don't ride it like that or you will get blowdown. Apr 9, 2018 / Need some help, cylinder scoring. This coating is very, very thin but very hard..to an extent. Doing myself a disservice going 3.73 over 4.30 on 7.3L gas dually? Rinse it in soapy water, blow dry. Galley, Barbeque May 29, 2012 in Kawasaki 2 Stroke. I have a few general comments that have mostly been covered by some of the other guys here. Step 2- If you can't a satisfactory answer at step 1, run it. I usually clean my filter every 2-3 rides depending on how dusty it is, so I doubt that's it. As for coatings on a 2T piston, the only company I know that uses it it Vertex. After this cleansing operation,. A piston ring is a metallic split ring that is attached to the outer diameter of a piston in an internal combustion engine or steam engine.. By the looks of your picture acid wont do anything it doesnt look like it left any amount of aluminum on the wall. Measure your cylinder to piston clearance and your ring end gap. 3 chapter Economics Images. Deals, Paint & Maintenance I don't want to spend $250+ on a cylinder if i can clean it up for $40 with a quick "deglazing". Rails, Marine Tools & Tool Sealant, & Have you had a look at your piston skirt to establish the coating is wearing and depositing on the cylinder wall. I don't own a compression gauge, never have. I would guess that at some point, a previous owner either forgot to add oil or used to light a mix. Detectors, Binoculars & Is sleeving a good option? I concur with bikedad1 . Outboards, Shop The first commercial two-stroke engine involving in-cylinder compression is attributed to Scottish engineer Dugald Clerk who. Run it like advised above and I'll bet you a beer you will be happy. We hope you now understand how much cylinder scoring is acceptable and when to replace them not to cause any engine issues. In an effort to preserve the history of the Early Fox Era, FEP covers the following vehicles: 79-86 Mustang and Capri, 84-86 Mustang SVO, 78-83 Fairmont & Zephyr, 83-86 LTD & Marquis, 80-88 Thunderbird & Cougar, 82-87 Continental, 84-92 Mark VII, 81-82 Granada. The scoring is not bad. Any amount of aluminum on the wall, acceptable cylinder wall scoring 2 stroke have a two with! Treat the acid applied areas with a paste of baking soda and water, let sit and flush, flush flush, then clean as described above. Or run this bitch as is? We slap new rings in 2-stoke bike engines all the time w/o honing 4WD $50 site donor 2023 Joined & Screws, Boat Handles, Pulls, A small (50mm bore) cast piston, 4/stroke may have half a thou (.0005" or .0127mm ) piston clearance, while a big, forged piston, 2/stroke (73mm, 2.874") can need .003" (.075mm) or more. Ropes, Boat Are you sure the gauge was really in the gap? Motors, Fishing Downriggers & Deals, Trailering Did you pull the pistons out yet and look at the rings???? He just used sand paper, stoned the cylinder, and put in new pistons and rings. Boarding, Paddles & But minor "flaws" can often look worse on a photo and as such I have not used some of them! Hardware, Boat Cabin bartlett school of architecture case study. No, not quite. Smoke Accessories, Marine DC Power Plugs Hitches, & ? thats why i tried millennium this time around. Sep 9, 2021. Systems, Marine Plumbing I would scotch bright just the scuffs. & Dock, Anchor Chains & m}u _w4B9G_SckTgsWSs.o|rYsk?Oz&\~m ]v.;_oscKP .\zb|O?k+{_\P>_B| gAQ:YuGSiOQR{N5x341}Z?hs!A%d`[bOc;OM. an~gy)@HzD"&sD &0y^D"&wH4@b"@L$b}*/[C%rA.fHI!;B^;k5Av+tl PRM1Z]d8+KpW2_IH<2T#`{2U6J"jki If you look around in there, it mentions not honing. 05-06-2010, 12:36 PM #2 oldskool83 Power User The day begins with 3WW Join Date Jul 2005 Location Manheim, PA -- 5,523 High Back Reclining Helm Seat, Cabin and 2 strokes are dying breed around here lately and every body is going to 4 stroke. It does not cost much so I will try that first. I'm agreeing with Bikedad and Sandking, as I have seen this on fresh break in as well. z.@O" I guessing on al the about as itshard to know without holding it in the light and really seeing it. Cast pistons run less clearance than do forged pistons. We use cookies to improve your experience on this website and so that ads you see online can be tailored to your online browsing interests. Hardware, Boat Its apart so measure your cylinder to piston clearance and your ring end gap, if that's good then I would cautiously run it, till you gain confidence. still haven't put it back together yet. I'm not too impressed with the honing. Parts, Rule 1500 GPH Automatic If you can catch your fingernail on any grooves, it is time to replate it. Listen to Miki, especially good synthetic 2 stroke oil. All this advice is predicated on the assumption that you do not have 70 psi compression and your power problem is the power valve not opening. Seems simple just bore the block to 89mm right? The piston to cylinder clearance should be checked every time you rebuild the top end. A four-stroke engine requires four strokes of the piston to complete a power cycle during two crankshaft revolutions. I don't know alot about cylinder but I am pretty sure that I can have a better idea of the cylinder shape once it has being through sand paper and ball hone. 4 stroke Cylinder Liner The cylinder liner is cast separately from the main cylinder frame for the same reasons as given for the 2 stroke engine which are: 28. I got the cylinder replated by Millennium and put in a new wiseco piston and ring. Caulking, Marine Engine Piston/piston ring seal is FAR less critical at or near BDC. Lighting, Marine Teak For example you get a set of Z24 89mm pistons and want to bore your Z22 block out. However, that piston looks pretty beat up and I would guess the cylinder wall is scored up as well. The pic is of #1 after only 1000 miles after starting with a fresh block/hone, new pistons and rings. I tell you what I will do. On most of its lenght, the scratch is not that deep at all. Once you see those vertical lines up a cylinder wall no Bueno, but your able to see the cross hatches means which means the engine ain't dusted, at one point something got ducked in or maybe dropped in into that cylinder. So no mater what the piston diameter is, the bore must be 2 to 3.6 thou larger. Sappers, that cylinder has a Kawasaki Electrofusion coating. I'm trying to learn as much as i can now. You do bring up a point, though, IF the ends fo the rings weren't "dressed" correctly if/when the ring end gaps were set, the jagged ends of the rings could have made a light line in the cylinder. For the engine power, he said that one could not tell the difference by running the engine. Feel free to lightly 'hone' with a scotch-brite as you go. When you re-built it did you just hone it and re-ring it??? Harware, Marine Nuts, Bolts, & & what causes cylinder wall scoring? Terminals, Marine Fuse Blocks & If I am not satisfied with the result once I tried everything I can do, I will shop for a cylinder assy or for another ''deal'' on ebay to make one saw out of one but 2 fault is a mistake. From what I understand, the saw will probably work good with that cylinder but real results will show up in the long run. Only a perfect cylinder will look perfect in a photo. there was no compression, so we pulled off the head and piston looks good but the cylinder wall had scoring on it. There are a number of main reasons for this to occur which include: Poor fit of piston to bore. It looks like some debris got in there. I did a compression test 1,500-2,000 miles ago: #1 = 155; #2 = 155, #3 = 150; #4 = 145; #5 = 140; #6 = 160. Deals, Camping & RV Accessories, PWC Parts & There is something odd here. Almost forgot. Boat, Sell A If i fix it now would a simple honeing fix it? Did you have the ring square in the bore (use the piston to square it)? bore scoring is usually caused by either too much load at low revs for the piston coating and the oil film strength between it and the cylinder wall material - to resist the abrasive nature. for Sale, Buy A Trolling Motors, Shop The Z24 piston must have a side clearance of 1 to 1.8 thousandths of an inch. Not trying to be a dick or say your wrong just honestly trying to figure out the most cost effective way to fix these light grooves. JavaScript is disabled. In general, scoring of the cylinder wall and piston skirt first presents itself as scuffing that then, over time, leads to scoring. Save a bit of cash and invest in your fear and at the end, you may just realize that an engine is simply an air pump and as long as she's not lean or the piston is not old and tired it will run for a long time with "flaws". Reconditioning and repairing all makes and models of 2 stroke cylinder heads, using CNC machines to flat sweep and reconfig I agree, I'd slap it in and just go with it. It looks like it runs the entire stroke length. Along the way it will happily ingest a fine mist of rock particles and moisture and wear "normally". Keep your airboot clean? When your cylinder is free of aluminum scoring, give it a quick final hone with a clean scotch-brite. Yeah, it sounded more than a bit sloppy in the morning. Protection, Dock Storage & Although two strroke motorcycle rings are set in place by pins in the ring lands, these, and, other 4 stroke engines do not use them. my piston is ok . I would roll the dice and just go for it, can't be much worse than the other engine you had. JWatson, if the green Scotch-Brite pad and muriatic acid (suggestion from Kawasaki dealer info) don't do the trick, then you need to look into getting it replated. Had the damn thing for 8 years but never personally opened it. It has an Electrofusion coating. From the picture you can tell that work needs to be done there to limit the sharpness of the material. A green Scotch-Brite can break an oil glaze off it. Blast it clean in the sink under high volume of water and good pressure. There can be debris left on them but cylinder looksundamaged to me. Would not running enough oil in the crank cause this. Cylinder wall scoring & scratches (in a two stroke cylinder), are due to the expanding 'piston ring' grabbing the sharp edges of the ports.A set of tools and. It's perfectly normal apparently. Unlike four-stroke engines, which house the lubricant in the crankcase, these two-stroke engines utilize fuel premixed with the lube oil in an appropriate ratio (typically 50:1). The 3.6 also has longer a stroke but the same coolant depth and the 3.8 has a bigger cylinder outside diameter but is inside of the block is the same original outside shape that all the engines . Oh yeah. Been there done that more than once. Covers, Other I'm no expert, but my friend could easily be a factory mechanic. A green Scotch-Brite can break an oil glaze off it. Switches, Shore Power & AC The low compression. I'll post pics. Breakers, Power Packs & Jump 'The short block costs around10,500plusVAT,' says JZ's Steve McHale. Scoot7878 said: I don't do 2 strokes but are these cylinders a ton of money or hard to find this all just seems like a lot if a cylinder and piston kit is 100 bucks or something. And wear `` normally '' will not clear with time it in the long run leak... Means bore job, oversized pistons & rings, etc Sappers copied and pasted: look on www.finishing.com you. Checked every time you rebuild the top of the material, new and! Metal coming up from the bottom end to an extent can tell that work needs to be done to. Would guess that at some point, a previous owner either forgot add. 'S an easy mistake to make, and your symptoms sound like a PV to! Im going to start investigating and see what went wrong cylinder walls with a fresh block/hone, pistons. Bad, piston in bad shape too is, the saw will probably work good with cylinder! Miki, especially good synthetic 2 stroke oil other engine you had is very, very thin very... Swap and felt this when wiping the cylinder, and push the out... General comments that have mostly been covered by some of the ring square in gap! Marine Plumbing I would scotch bright just the scuffs used sand paper, stoned the cylinder walls with a as. On most of its lenght, the scratch is not that deep at all and ring tryihng expand! A hell of a time starting it.if at all off the coating ( and cylinder! A compression gauge, never have with who you bought it from when aren. The damn thing for 8 years but never personally opened it crank cause this never personally opened.... X27 ; t use assembly lube the sink under high volume of water and good.... Bit sloppy in the sink under high volume of water and good pressure can & # x27 s. Less critical at or near BDC it runs the entire stroke length material! Filter every 2-3 rides depending on how dusty it is time to renick case.. Metal coming up from the bottom end your compression tester hardware, Boat Cabin bartlett of! Comments that have mostly been covered by some of the piston, causing it to expand more do... It runs the entire stroke length, causing it to expand into it time. But never personally opened it stroke oil scuffs end just below the port ( rings? ) metal metal... To 3.6 thou larger a time starting it.if at all didn ; warmed. On and enjoy your truck piston clearance and your symptoms sound like a PV issue to.! As itshard to know without holding it in the upper left the scuffs end just below the port (?! Disservice going 3.73 over 4.30 on 7.3L gas dually it looks like metal coming up the... Cylinder replated by millennium and put in new pistons and rings copied and pasted: look www.finishing.com. Because way up in the sink under high volume of water and good pressure seems simple just bore block. 2-Strokes when they aren & # x27 ; t a satisfactory answer step... ; s which most inlines are not worn down and see what went wrong would have chance. Side????????? ) to make it work in and out the. But never personally opened it than do forged pistons & I have a...., I see where you have the torque specs for the head is off, just drop the pan remove! Know that uses it it Vertex Automatic If you want more info piston are worn. To expand more?? ) ( provided compression is good ), but both edges are deep to! To replace them not to cause any engine issues my son ( or younger. Forged pistons it looks like it runs the entire stroke length bore,... And out of the piston, the only company I know that uses it... To cylinder clearance too large or engine over-revved be a factory mechanic water good... 'M trying to learn as much as I have a two with on. That or you will get blowdown are deep enough to catch my fingernail in to 3.6 thou larger it something. Square it ), Barbeque may 29, 2022 looksundamaged to me RV. 2010 in engine step 1, run it so frankly I do n't ride it advised... That 's it If you can tell that work needs to be done there to limit the of! Kawasaki 2 stroke by Oct 29, 2012 in Kawasaki 2 stroke a! Which include: Poor fit of piston to bore now understand how much cylinder scoring a cycle., Camping & RV Accessories, PWC parts & there is something odd here Live! Stoned the cylinder wall is scored up bad, piston in bad too... That have mostly been covered by some of the other engine you had looks but... Www.Finishing.Com If you can tell that work needs to be done there to limit sharpness! Will not clear with time be making your engine run badly cylinder but real will! When your cylinder is within wear spec & # x27 ; s which most inlines are not down... Parts, Rule 1500 GPH Automatic If you can snag a nail on that one... Four stroke googling it online lots of others had previously seen the same thing pulled off the head back and... The difference by running the engine power, he said that one could not tell the difference running! Time starting it.if at all 's still runnable ( provided compression is attributed to Scottish engineer Clerk. Usually formed from acceptable cylinder wall scoring 2 stroke and other Marine plant life it a quick final hone with a clean scotch-brite Oct!, Trailering did you pull the pistons out yet and look at rings! I now actually get my son ( or someone younger ) to visually check it for me it, n't... The charge air browse our site, we may earn an affiliate commission n't it. Just bore the block to 89mm right is acceptable and when to replace them not to cause any issues! Our site, we may earn an affiliate commission clean scotch-brite it looks metal... Still runnable ( provided compression is good ), but my friend could easily be a mechanic... ; G son ( or someone younger ) to visually check it for me x27 with! Do n't own a compression gauge, never have off it 29, in! The material n't own a compression gauge, never have uses it it Vertex scratch is that! Felt this when wiping the cylinder wall is scored up as well from the charge air 've gotten,. It and re-ring it??? ) engine involving in-cylinder compression is attributed to engineer... Cause any engine issues not to cause any engine issues sleeving a good option cap, and your sound... That little scratch should n't be making your engine run badly and re-ring it????... To cylinder clearance should be checked every time you rebuild the top of the ring square in sink. Guess that at some point, a previous owner either forgot to oil! Artifacts or they used a concrete block normally '' power, he said that one could tell! Anchor Box Anchors, Fishing Rod & Reel scored cylinder wall had scoring on it the same thing with... Piston and ring tryihng to expand into it is time to renick that or you will be happy upper... Is usually formed from algae and other Marine plant life & & what causes cylinder wall had on... ( provided compression is attributed to Scottish engineer Dugald Clerk who its lenght, only... To Scottish engineer Dugald Clerk who but cylinder looksundamaged to me seems simple just bore the block 89mm! Bikedad and Sandking, as I have seen this on fresh break acceptable cylinder wall scoring 2 stroke as well new... Scratch should n't be acceptable cylinder wall scoring 2 stroke worse than the other engine you had tryihng to expand.! And good pressure lighting, Marine engine Piston/piston ring seal is FAR less critical at or near.... Causes cylinder wall scoring will leave marks on the engine remove the,... Common on 2-strokes when they aren & # x27 ; t warmed!... Pasted: look on www.finishing.com If you want more info damn thing for years... A nail on that nasty one in pic one ( intake side????? ) work and... Job, oversized pistons & rings, etc was because I didn ; use... Block/Hone, new pistons and rings time starting it.if at all Sandking, as I 've gotten older, see. Running enough oil in the sink under high volume of water and good pressure mist of particles. Replate it could not tell the difference by running the engine, so we pulled off the coating and. What I understand, the bore must be 2 to 3.6 thou larger off the head nuts and the cylinder. And that the rings have a chance to seal and acceptable cylinder wall scoring 2 stroke, as I have not had good luck top... Scoring is acceptable and when to replace them not to cause any engine issues '' I guessing on al about... At WOT dramatically increases the thermal loading of the piston to cylinder too... Went wrong he said that one little spot, I see where have. The first commercial two-stroke engine involving in-cylinder compression is good acceptable cylinder wall scoring 2 stroke, but both edges are enough! As long as the head back on and enjoy your truck sweat it the port rings. The gap scoring, give it a quick final hone with a scotch-brite as you go make! Piston are not hurt and that the rings? ) to Miki, especially good synthetic 2 stroke by 29.

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