Re: OLD BLUE,85 marathon re-construction
 

Nope I missed that one! OUCH! What if you got the new block cryo-treated first? I know in high powered car blocks they say it helps? :dontknow:

New Trend: Windmill powered gold cart... :lhmo:

Re: OLD BLUE,85 marathon re-construction
 

good thought jerm,but im bout tapped out money wise..
heres the best elec start block deal i could find,,it does come with new bearings and engine cover8)

http://www.ebay.com/itm/Launtop-13hp...c38f9b&vxp=mtr

here engine build thread;
http://www.buggiesgonewild.com/big-b...llet-beef.html

Hope you get it figured out...seems like a lot of $$$ just to get a gx390 back in the game.

Re: OLD BLUE,85 marathon re-construction
 

it did start out cheap remember:lol: it should be good a long time uness i kill it with high rpm,s..
at least i will have all these good parts an maybe move up to the billet flywheel someday if this goes well..its a learning thing..i will fix the block and bore the crap out of it for the future,2nd small engine full race build:lhmo:

i cant seem to find this answer online but id think the new block should be ready for the new piston and rings? anyone?
new block= newly machined cylinder wall and id think thats how there installed when new.right in the freshly machined hole..after cleaning of course..cant belive i cant answer this online..
screw it,im calling the machine shop:thumbup:

yep,could have had 2 complete 460cc clones for what i have in it now..def gotta keep it till the end now..

I would take the block and piston/rings to the machine shop to get them matched together. But if you have a micrometer or something else to measure clearances and feel knowledgeable enough...you can do it yourself to see if they match up.

After all the money you have invested I would think you want it done right. I don't have any tools to set up engine clearances...so I leave that to someone else!

Re: OLD BLUE,85 marathon re-construction
 

rest assured,,this is just my first time messin with a small engine..i have almost every tool i could ever need..been savin them for 30 yrs and have some i forgot what they were for :lol:
yes ive already measured every thing of importance and have those numbers wrote down..
actually,the reason im still going is i cant stop myself..once i start something and its not right i cant leave it alone..:mrgreen:
when the crank gets here today i will pre check the clearance with plastigauge i got from jegs,,if the billet rod has more than .003 oil clearance its going back as thats what i want,,or,the crank will get turned to my specs and i will get a .010 under bearing from arc...
crank bearing clearance in real world is .003,and not over .004 and not under .002,,,i will settle for 2-3 but 4 make me wanna cringe,but then again it ran sweet with7-.008 and knocking:shock:
im only gonna be so picky now because i have went past what i was going to do because the po did a crappy job imo..i still want basically stock just dependability for a couple yrs..then again these motors are kinda fun:thumbup:
the small port and polish to the head will /should amaze me my dad thinks..pics in motor build thread.

Re: OLD BLUE,85 marathon re-construction
 

got the clutch back together with new helix.
http://www.buggiesgonewild.com/gas-e...tml#post875403

That sucks about the motor. Sounds like it going back together soon. Good luck!

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Great news man...can't wait to see it fire up again!