Promax rebuild

[xpressman al]

My promax melted #5. I've found a reputable machinist in my area and now I need recommendations on what to have done. Things such as porting, decking the front half, stuffing,and balancing. I'm going back with top pin pistons metal caged bearings and shaved heads. I don't want to look back and wish I'd done more while it was apart. Thanks guys

[specboatops]

What type of hull is the motor going on ?

[xpressman al]

Its a bullet 20xf. Pretty decent speed wise...

[rgsauger]

Nobody better than Jay Smith over here in Houston on those motors. Been a LOT of good motors screwed up by well intensioned machinists. Just a thoughts. Jsre.com

[xpressman al]

Jay Smith won't machine an engine he isn't going to assemble. I will be assembling myself

[myron]

not true, jay did a pro max block and front half for me, I put it together myself.

[TEXAS20225]

you guys dont know jay smith does NO machine work??????He is not a machinist he sends all his to two different shops

[TEXAS20225]

i think he still sends them to Jim ruck replacement ( i sent mine there also ) before he sold out and did for years and a local Houston shop

[TEXAS20225]

I will tell you this the machine shop work is what makes or breaks the rebuild i do a lot of steel sleeve motors every year. ive rebuilt two promaxs this year and a few 200,150 and one 300x all my machine work is done by someone who also builds motors and runs them!! anyone can assemble pistons on rods and install new guts i do it every week and have for several years good straight holes are a must and if you aint savy you can get hosed big time always check your finished bores with a fowler bore gauge check it top middle and bottom of sleeve be sure your machine shop uses sunnen ridged hone for a straight hone job and so on( thats cross hatched) not round de round and port champhering is a must, wash your motor with hot soapy water and a stiff nylon bristle brush, rinse, air dry, wipe it down with light oi,l start assembly immediately, keep your hands and tools clean as well as your surroundings, rotate you short block after each piston is installed make sure it rotates freely i assemble mine with a 25:1 fuel merc oil mix and keep it wet good luck

[Jay Smith]

you guys dont know jay smith does NO machine work??????He is not a machinist he sends all his to two different shops

Come in any day to JSRE and you'll witnessed me machining and welding if needed on my own customers parts and put the above rumor to bed .. I've ran the same J headed Bridgeport Mill , Jet lathe and Miller Heli arc machines for 20 + years...


LOL my wife told me to tell all the non believers to come help her sweep all of that "make believe" aluminum under these machines she sweeps up every evening after hours..

The ONLY machine work I will farm out is CNC work, ( Cause I don't own one ) , boring work , and boring related to block plating...But when a plated motor returns I grind at least an hour on each.


Getting back to building a successful motor I find round holes and the correct clearances is key for a motor to make power and live.. Owning and knowing how to read a dial bore gauge is a must assuring bores are straight and at the correct clearance.. I check EVERY bore AND piston ring end gap before a piston goes in every motor that comes from my shop , I "trust" no one other than me because I am after all the one with my name attached that is what my customers expect ...

BTW: I also run every complete runnable power head I build 2 hours before shipping tuning and catching anything wrong BEFORE it goes to the customer....



Jay

[xpressman al]

Mr. Smith I understand and respect your decision to only machine engines that you will assemble. As you said your name is on the block and you are a highly respected member of several forums and gained that respect for a reason. I called and spoke with you about machine work and you recommended Ruck since I'll be assembling myself. What I need help with is a build plan ie; port work, front half cutting and such so I can have an engine that suits my needs. My engine is on an 1050lb hull and I'd like quicker revving and acceleration. I will be cutting the heads, shaving the front .050, and balancing the rods and pistons in addition to durability items like top pinning and metal caged bearings. Thank you for your help

[Jay Smith]

Thanks for the kind words ! Anytime I can help you with a build path by all means give me a call...IE: torque mods such as cutting front half , epoxying # 2 oiler gear cavity with a heavy hull can pay huge dividends on the bottom end torque trying to move the heavier load...Sounds like your on the correct path to making a torque animal, if in the future you need advise you have my number..

Good luck,
Jay

[xpressman al]

What's everyone's opinion of a 9 or 16 amp lightweight flywheel and stator on a bass boat with 2 fish finders? This isn't a tournament boat. It's a fish 4-6 hours for fun sometimes at night with the nav lights on boat

[TEXAS20225]

well i stand corrected ill call mister Ruck and tell him he has some competition( He is still working just behimnd the scenes ) im not sure what your doing jay since you named off all the machining articals that matter to a motor rebuilder all the exhaust cutting and slag removal is a form of machine work i guess, are you replacing sleeves decking and ridged honeing?? with a 8 stone sunnen , just curious or just cutting heads to make them shavings

[albypine]

http://www.diamondmarine.com