This is a big NO NO! The case is aluminum and if you use a die grinder and scotch brite you take the chance of removing some aluminum and making the sealing surface uneven. I've personally seen this on a block that a dealer used the die grinder/scotchbrite method and ended up have to have the case welded and resurfaced. Razor blade is the only way to go. The reason your having such a hard time removing the material is someone must have used a "gasket sealant". I only use a trace amount of petroleum jelly (vasaline), just enough to darken the color of the gasket. An old mechanic taught me this trick and has work perfectly on every rebuild I've done ( 15 or 16 over the years). The gasket is designed to make the seal and if parts are flat and true that is all you should need. Good luck, Just my 2 cents worth.
Base gasket help
- Thread starter indy_500
- Start date
This is a big NO NO! The case is aluminum and if you use a die grinder and scotch brite you take the chance of removing some aluminum and making the sealing surface uneven. I've personally seen this on a block that a dealer used the die grinder/scotchbrite method and ended up have to have the case welded and resurfaced. Razor blade is the only way to go. The reason your having such a hard time removing the material is someone must have used a "gasket sealant". I only use a trace amount of petroleum jelly (vasaline), just enough to darken the color of the gasket. An old mechanic taught me this trick and has work perfectly on every rebuild I've done ( 15 or 16 over the years). The gasket is designed to make the seal and if parts are flat and true that is all you should need. Good luck, Just my 2 cents worth.
Opinions are like?? Every one has one!!!
Scotch Brite roloc on a die grinder is not suggested for Non material mating surfaces (case 1/2's) They are designed by coarseness application (From steel to brass mating surface) on material sealed mating surfaces (base gaskets, heads gaskets,water,oil pumps, etc...). Yama bond/ 3bond and some Loctite product I can't remember the number of are desinged as a sealant to cure in the absence of air between two machined mating surfaces (case 1/2's). The copper sprays main purpose is to create a similar bond as the 3 bond type sealant but to soft metal (steel rimmed/ impregnated gaskets). If you ask a true engine builder he will probably say "I dont like to get sweat from my brow on a paper gasket, Put em on dry to a super clean surface". These are more or less the facts about sealing surfaces by my book but here is the kicker. You can't allways get the perfect world so do the best you can. Base gaskets and the biggest pain in the arsh when you aren't taking the motor completely down. A razor blade is the only thing to use (with a cover over the crank and rod) to get the material off and you will get nicks. As you try to clean the surface for sealing you seem to get as much dirt back on the area as you have sprayed and blown off. It sucks!!!
Now I get to be a hypocrite. When I have to do a base gasket like you are doing, I cheat a little. I use a razor and get nicks in the metal. Then I use a good, clean, long, medium to fine file and try to knock the tops off the nicks. There are no clearance issue here unles your nicks are bigger than the gasket is thick. I clean both surfaces with an spray cleaner (elec or brake) sprayed on cloth. Some of the time I do use a "SMALL" amount of 3 bond to hold the gasket in place. This is more as an adhesive than sealant. I can't recommend the copper spray because I have seen it react to paper gaskets by saturating into the paper and delaminating.
I just added one more to the Opinion Pile
Good luck
Scotch Brite roloc on a die grinder is not suggested for Non material mating surfaces (case 1/2's) They are designed by coarseness application (From steel to brass mating surface) on material sealed mating surfaces (base gaskets, heads gaskets,water,oil pumps, etc...). Yama bond/ 3bond and some Loctite product I can't remember the number of are desinged as a sealant to cure in the absence of air between two machined mating surfaces (case 1/2's). The copper sprays main purpose is to create a similar bond as the 3 bond type sealant but to soft metal (steel rimmed/ impregnated gaskets). If you ask a true engine builder he will probably say "I dont like to get sweat from my brow on a paper gasket, Put em on dry to a super clean surface". These are more or less the facts about sealing surfaces by my book but here is the kicker. You can't allways get the perfect world so do the best you can. Base gaskets and the biggest pain in the arsh when you aren't taking the motor completely down. A razor blade is the only thing to use (with a cover over the crank and rod) to get the material off and you will get nicks. As you try to clean the surface for sealing you seem to get as much dirt back on the area as you have sprayed and blown off. It sucks!!!
Now I get to be a hypocrite. When I have to do a base gasket like you are doing, I cheat a little. I use a razor and get nicks in the metal. Then I use a good, clean, long, medium to fine file and try to knock the tops off the nicks. There are no clearance issue here unles your nicks are bigger than the gasket is thick. I clean both surfaces with an spray cleaner (elec or brake) sprayed on cloth. Some of the time I do use a "SMALL" amount of 3 bond to hold the gasket in place. This is more as an adhesive than sealant. I can't recommend the copper spray because I have seen it react to paper gaskets by saturating into the paper and delaminating.
I just added one more to the Opinion Pile
Good luck
trailshredder
Member
Don't sweat it big bill. My mechanic has been rebuilding snowmobile and boat motors for 32 years. This particular pad we are using comes from snap on and this is its designed purpose. He doesn't put all of his weight into it when cleaning surfaces. I am sure he is smart enough to know what he can and can not do. So far we have 0 comebacks....he must be doing something right. And as far as a gasket sealer...we do not use any unless it is neccessary and he prefers the copper spray so if the engine has to be taken apart again the gaskets will come off easier than if you were to use the three bond. Everyone has their own little way to do things so your opinion is greatly appreciated.
indy_500
Well-known member
Couldn't find 3bond so the one helpful guy out of o reillys/fleetfarm/napa was at napa and told me yamabond is the same thing and went to appleton powersports and got it. THe one base gasket i had left came off easy, my dad set a heater on it 3 hours ago so it came off nice and easy.
trailshredder
Member
Yama bond three bond all the same.....it's going to take you 3 hours to get apart again. We will see this thread again this year or soon next year....you didn't split the crank!!
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indy_500
Well-known member
You mean you'll see it again from the person that buys it while i'm riding a fusion?
btw she runnin goooooood! trailshredder
Member
You mean you'll see it again from the person that buys it while i'm riding a fusion?
Good job Indy...I would sell it know!!!
indy_500
Well-known member
I think i'm going to put it on CL tomorrow night. I found the PERFECT fusion. But at least it's running good and no leaks for the next owner, i couldn't sell it to a new owner screwing them over. I still have minor clunking when breaking, but I think i've narrowed it down to either jackshaft bearings (but they seem fine) or since i regeared, the chain takes a really sharp angle after going around the bottom gear and when you brake, the chain bangs against the tensioner and clunks. The clunking gets better or worse every time i adjust chain tension.
trailshredder
Member
I am happy she runs good for you.....good job!!
indy_500
Well-known member
I almost forgot! I had it all back together. Went to mix the coolant and put er in, came back, looked at my seat, and the drain plug on the bottom of the carb was sitting there! lol i cleaned the jets before putting it back together and almost made a big uh oh. Glad i caught it. I once already forgot to hook up the fuel line to the carb on my dads sled and i couldn't understand why it was running on 1! open the hood and get gas sprayed all over me... you live and you learn.
mjkaliszak
New member
Indy... I have to hand it to you. For your age , your quest for knowledge is impressive. You learn by doing ( IMO ). I wish my son had the interest in mechanical items like you. He is 13 and has had everything " provided " . Maybe my mistake as a parent but time will tell, maybe he will turn over a new leaf some day.
After reading the abundance of advise , the importance of " decking " becomes apparent. As said above the sealant ( whichever brand ) is just an adhesive to hold in position the gasket. ( In a perfect world ) or to take up slight descrepancies in " flatness ". I have found most motor components when assembled at the factory then taken apart the 1st time to have no sealant . They are " fly cut " when machined originally which provides a flat mating surface. Over time , heating - cooling , torque-ing of bolts, assembly - disassembly, directional forces all contribute to distorting the originally flat surfaces. Some motor guy's re-deck the surfaces to restore the flatness. I have used a surface plate & emery paper to " lap " the surfaces of jugs , heads flat again. Just my .02, but wanted to throw it out there with the pile of opinions. I have even dykem blued them to find the high spots. Nothing is better than flat & clean, with just the gasket only. But that's why they make sealants, nothing is perfect.
After reading the abundance of advise , the importance of " decking " becomes apparent. As said above the sealant ( whichever brand ) is just an adhesive to hold in position the gasket. ( In a perfect world ) or to take up slight descrepancies in " flatness ". I have found most motor components when assembled at the factory then taken apart the 1st time to have no sealant . They are " fly cut " when machined originally which provides a flat mating surface. Over time , heating - cooling , torque-ing of bolts, assembly - disassembly, directional forces all contribute to distorting the originally flat surfaces. Some motor guy's re-deck the surfaces to restore the flatness. I have used a surface plate & emery paper to " lap " the surfaces of jugs , heads flat again. Just my .02, but wanted to throw it out there with the pile of opinions. I have even dykem blued them to find the high spots. Nothing is better than flat & clean, with just the gasket only. But that's why they make sealants, nothing is perfect.