Sand Suface Rust on block with WD40???

MA70-3.0GT · 05-19-2010, 02:23 PM

I'd say for MHG purposes you likely need to get the block refinished now as the surface roughness tolerances are in the single microns range i.e. you need pretty much a mirror finish for it to work properly. For fitting a stock HG I was advised that it was possible to lightly sand the deck surface to remove crap but that it was to be done evenly if at all & not in any one area, using a piece of plate glass as opposed to a block & with at least 1200/1500 grit paper, anything lighter if available.

I don't know how much surface rust there is though but if you're thinking in terms of 800 grit paper I'd imagine theres enough surface damage to warrant refinishing now if only for your peace of mind... If you do end up sanding after all then I'd say WD40 is fine as a lubricant as that's what I used, but do bear in mind that was still only for a composite HG.

05-19-2010, 02:23 PM	#4
MA70-3.0GT 12psi boost Join Date: Oct 2009 Location: Crewe, England Posts: 356	I'd say for MHG purposes you likely need to get the block refinished now as the surface roughness tolerances are in the single microns range i.e. you need pretty much a mirror finish for it to work properly. For fitting a stock HG I was advised that it was possible to lightly sand the deck surface to remove crap but that it was to be done evenly if at all & not in any one area, using a piece of plate glass as opposed to a block & with at least 1200/1500 grit paper, anything lighter if available. I don't know how much surface rust there is though but if you're thinking in terms of 800 grit paper I'd imagine theres enough surface damage to warrant refinishing now if only for your peace of mind... If you do end up sanding after all then I'd say WD40 is fine as a lubricant as that's what I used, but do bear in mind that was still only for a composite HG. __________________ '89 MA70 Supra GT aero 3.0turbo JDM, Rebuilt motor, K&N intake, 3" stainless turbo-back. New turbo and braided line kit... '89 Honda NC27 400, NC23 cams, open pipe, PC36a shock & possibly Showa USD forks... '83 Yamaha 29R XJ750E-II, number 69 off the line, only runner in the country? Original except Koni shocks '95 Honda PC26 CB500R, Winter hack, hateful, trying to sell it I'm not paranoid, they really ARE after me!!!