Cylinder hone with engine in situ
Discussion
I'm going to replace the rings on the missus MX5 soon. My question is after I've honed the cylinders I need to wash the material out. Everything I've read suggests using copious quantities of soap and water. I plan on leaving the crank in place. Am I likely to knacker the crank bearings or can I get away with wrapping it carefully in cling film or similar.
I suggest it would be very foolish to try and do this with the crank in situ. Firstly the crank webs will restrict how far you can hone through the bottom of the bores although if it's only one of those little 3 prong spring loaded hones you are using rather than professional gear you might get away with it. However the grit gets everywhere and it's not going to take much of that to ruin the bearings and journals.
I guess if you just lightly hone the top part of the bores down to where the rings run to and pack everything below that with rags it might just work.
Definitely don't use soapy water in anything other than a stripped block which is about to go into a paraffin tank afterwards anyway. Just use clean rag moistened with paraffin and then paper towels or more dry clean rag. However any grit that escapes past the bottom of the bores will probably never be able to be cleaned out. It'll get into nooks and crannies, crank oil holes, down the sides of the main bearings etc. Take the engine out and do it properly.
I guess if you just lightly hone the top part of the bores down to where the rings run to and pack everything below that with rags it might just work.
Definitely don't use soapy water in anything other than a stripped block which is about to go into a paraffin tank afterwards anyway. Just use clean rag moistened with paraffin and then paper towels or more dry clean rag. However any grit that escapes past the bottom of the bores will probably never be able to be cleaned out. It'll get into nooks and crannies, crank oil holes, down the sides of the main bearings etc. Take the engine out and do it properly.
If you're stuck I'd go for it. Do the hone with lube. Scrub out with copious amounts of soapy water and then wipe the bores with clean kitchen paper. If it stays white then the bores are clean of grit. Smear grease around the crank etc. You should be fine. Only do it on your car though, not somebody elses!
OK, I'm familiar with flex hones. I suggest you pack the bottom of the bores very solidly to prevent anything falling through and just hone to where the rings run. Anything below that is not important. In fact most ring sealing takes place in the top inch or two of bore and below that the pressure drops rapidly anyway.
If it were me I might be tempted to turn a bit of wood on the lathe to exactly the bore diameter and slide that down and then seal round the edges with grease. Without a lathe you'll just have to invent something from rag or cardboard taped up into a circle. Also tape up the waterway and oil holes in the top of the block with masking tape. Make sure the bores are bone dry with thinners or white spirit so they clean out easier. Even with a flex hone try and achieve a 45 degree cross hatch by moving the hone up and down in time with the rotation. Then hoover out and scrub out with rag before removing the packing and wiping the grease off.
If it were me I might be tempted to turn a bit of wood on the lathe to exactly the bore diameter and slide that down and then seal round the edges with grease. Without a lathe you'll just have to invent something from rag or cardboard taped up into a circle. Also tape up the waterway and oil holes in the top of the block with masking tape. Make sure the bores are bone dry with thinners or white spirit so they clean out easier. Even with a flex hone try and achieve a 45 degree cross hatch by moving the hone up and down in time with the rotation. Then hoover out and scrub out with rag before removing the packing and wiping the grease off.
If you use cutting oil it'll just make everything much harder to clean out and lead to debris running down past your plug seal. For small amounts of stock removal hones can either be used bone dry or with lubricant. However once you get the stones wet and they soak up lubricant you generally then have to use them wet in future as moisture will leech out of them and lead to a neither one thing nor the other situation. I used to keep some stones bone dry and as new and others for wet use.
Obviously for large amounts of stock removal then cutting fluid helps considerably to reduce stone wear but this is not your situation. All you're really doing is deglazing and conditioning the bore surface.
Obviously for large amounts of stock removal then cutting fluid helps considerably to reduce stone wear but this is not your situation. All you're really doing is deglazing and conditioning the bore surface.
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