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Fixed

Just started up my TZ after 7 months of not racing temps stay under 200F when idol very impress motor sounds great can't wait to race it.

hello... my TZ3 has just been through its 2nd race last weekend and i was satisfied with the performance running againts novas,TZ5,Sirio's S....

anyway after the race i decided its time to dissamble it for inspection on the parts..

1. the top of the piston has black spots, compression still very strong...
2. the internal bearing brown colour, no excessive play and no need to replace i think
3. the cshaft internal and sides were very brown/rusted i think
4. the conrod has quite a freeplay againts the cshaft pin, so new conrod coming...

btw i have replace the conrod...but there is still freeplay againts the cshaft pin ( so should there be no play or a little or what...) or the c/shaft pin has worn out also

BTW my engine has gone through 3- 4 litrs of fuel (25% nitro, P6 glow plug, and 0.4mm head clearance)

like to hear some comments on this conditions...thank u..

Take a look at post #1367 on November 19th last year. Not only was my big end to crank pin fit very bad, but also the top of the piston was badly pitted!
I returned the motor to Tower and they replaced it, no question.
I haven't run the motor yet, as I got a Nova Rossi in the interim period

Nosram it's good to hear Tower was so nice about that problem. Those were your pics back a while ago huh? That was a messed up engine.

hey guys
i think my front bearing is worn, the one under the carb.

after every race i notice alot of oily gunk stuck on the carb above the flywheel. the engine runs fast and stroing and the temps are consistent.

could it be the front bearing or maybe still a rich tune? what size is this bearing?

These are the prices from http://www.pro-s-futaba.co.jp/ they a crazy cheap at these prices i orded two of each

21535000 conrod 1980yen = $16 USD
21533000 piston and sleeve 4500yen = $38 USD

Don't panic mrgsr - it's just the engine trying to tell you that it's running rich on the LSN. You would be able to lean the LSN a little and you may need to richen the HSN to keep the temps in check once you get the LSN right.

It only needs to be a little bit rich to force some oil out through the front bearing as it is lubricating it. Once this hits the flywheel it goes on the carb and anything else that is in the way of this radial arc.

Cheers,

Mike.

I think that it would be time for a new rod but not the crank. You should get another 3-4 L out of it. Are you putting after run oil in after each race day?

what fuel you running? i think the oil in it is whats giving you that color inside the motor.i run byrons,and after 2-3 gallons my motor is nice and clean inside.

IS THERE IS SOMETHING ABOUT THE OS ENGINE THAT COULD BE IMPROVED,
BEARINGS, THAT'S IT THEY DON'T LAST LIKE NOVA'S, LUCKILY I HAVE ACCESS TO NTN OR SIMILAR BEARINGS WITHOUT ANY PROBLEM, FOR 1/3 THE COST OF ORIGINALS IN THE US

What is NTN?

NTN is a brand name bearing manufacturer.

I agree, I think that I go through two sets of bearings to a P/S and rod set. What are the part numbers that you are using as replacement bearings? Can you get them at McMaster Carr?