Once torn completely down, a machine shop can heat the block, rotate the sleeve into position, and pin the sleeve to prevent future rotation (or simply replace it with an oversize sleeve).
Once torn completely down, a machine shop can heat the block, rotate the sleeve into position, and pin the sleeve to prevent future rotation (or simply replace it with an oversize sleeve).
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 48 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
Crosshatch on cylinder looks great, may explore having existing cylinder rotated and pinned. Definitely have some work ahead of me. Anything else I should replace while I’m in there as preventative? Thank you for all your help!
EuporeanAM - I saw a post on another thread from you about overtorquing causing the cylinder sleeves to rotate, especially the lower cylinders.
Curious on how that is caused, or if it is still an overheat issue because of the extra torque.
The previous owner replaced my lower unit, and wondering if a the lower locked up or something, if that could've caused this. I don't know the details on the lower unit issue from the previous owner, just trying to avoid future issues after I get this fixed
I’m a machinist and I’m trying to figure out how you would do that. If you heat the block enough the sleeve will expand also. Now you can bore the old sleeve out and freeze new sleeve before putting in. Naturally all tolerance’s would have to be in spec. Would like to know more on that process. Learn something new everday
The sleeve is a different metal composition than the cast aluminum block. I think they are nikasil or something similar. I'm more interested in what causes a sleeve to get turned?!? Stormzm, I'm glad you figured this out without throwing more parts at it. Hope your downtime is short lived!Originally Posted by 1ranger487vs
Pretty sure nikasil is a coating can’t bore it. I’m thinking that sleeve had a lose fit when installed. Not talking much on a interference fit
You are correct, but the sleeve is a different metal than the block itself. One of the experts will be along to explain the process of removing and installing a new sleeve. From what I've researched it is not a job for a novice.
Any suggestions on how to go about pinning the sleeve if we’re able to get it rotated back into position?
I’ve done it on motorcycles 2s. Had to bore out old sleeve and bore bare cylinder to the size needed. Than you heat cylinder and freeze sleeve. Slides right in if done right but you only have seconds to line up ports. 1 shot. That’s why I’m waiting to hear how they do it.
I got the block completely stripped today, will call around for machine shops on Monday. Cylinder 6 sleeve rotated about 3/4”, some ports were almost completely blocked off. Will order a new .020 over size sleeve Monday and get the process going. Hoping to have it back running in a couple of weeks.
Overheating would normally (not always, but NORMALLY) affect upper cylinders first. In most cases where #6 is rotated, it is due to over-torquing the powerhead mounting hardware (fasteners 9 and 10 as drawn in the service manual) which can distort the block casting and permit the sleeve to rotate. Those two nuts are not torqued in the final sequence (they remain at 25 lbs/ft).
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 48 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
Do you know if those bolts were messed with or is like it came from mercury
I don’t believe they have ever been touched… hard to say for certain as I am the 2nd owner but they didn’t appear to have even been removed
I've seen guys heat a block with a propane torch that has a big nozzle.
They use a homemade tee handle with a slide hammer to remove the sleeve or spin it.
I've seen the block heated in an oven or grill to 425-450 degrees, after which a very heavy gloved hand (or a couple taps with a wood block) can easily rotate or perhaps even remove the sleeve.
Still need a machinist to either pin (or replace sleeve with an oversize).
Last edited by EuropeanAM; 03-30-2022 at 08:09 AM.
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 48 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
European AM- Can you confirm service manual for my engine is 8M8000017. Motor SN is 1B903220. Will be ordering my manual off your website asap. Thank you!
You asked about pinning the sleeve. First the shop has to have a milling machine big enough to mount a v 6 block at the right angle. Then it’s a simple job with an end mill. Don’t know any shops around here that would be able to turn that sleeve. Boring that block would take some special equipment. Maybe a specialty car machine shop or hydro tech. That block has to be mounted precisely and cannot move. Only talking thousands of an inch from good to bad
Recommend using email contact for manuals- often the information shown may not necessarily be the best choice available (in your case, I recommend Part# 8M0122849, even though it shows a later serial number range, it IS the most complete manual version specific to your 250 ProXS and will provide you with the most up-to-date manual for that series).
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 48 years (learn something new every day).
Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor
So I’m currently ready to reinstall my powerhead. Can anyone tell me what direction the shift rod that attaches to the linkage is supposed to face? I’m assuming straight forward… can’t find it in the service manual (I’m sure it’s in there somewhere). Rod lifted out of the midsection a little when pulling the powerhead and I want to get it in the right orientation before I drop the powerhead back on. Thank you!
So what did you do to fix it turn it or sleeve it
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