looking for some info on whether or not i should be loosing fuel [only when running].its only a very small bit but i dont think it always did that ,if u go to cen site you,ll find an exploded view of nt-16 its loosing fuel around parts 20 , 17 , 09-crank case. is this cured by replacing the front bearing bearing.
Here are the part no. of suspected area G-70337-17 , G-70337-20, G-70343-09.
have alook and see does that make sense, thats where the fuel is leaking from,
hopefully not to bad , a bearing is most likely the cause of this

regard madmark

how much fuel have you run thru the engine... I'm working on my 4th gallon almost finished and engine is bone dry especially around the front bearing... Have you checked that its not leaking around the carb... I know its a stretch but worth a look.... there was a response from cen a while back about leaking front bearings and they didn't seem to think it was a big deal.... More likely just more work to clean after running.... I'm wondering however, if your bearing went bad, hopefully your crank isn't bent....

i've about 4 gallons [25%] gone through , only a very small amount of fuel leaking out ,i mean very small, i dont think the crank is bent though ,because i took out the engine and done a bench test could not see any movement in crank it was smooth, no deflections or any of that type of movement . if the bearing is leaking out fuel that means it is drawing in in air as well does this mean my fuel mixture could be changed, and running leaner than i think it is.
u know of any way to test or see for definite if the crank is bent ,i imagine if it was though i would strip gears quite alot .

thanks madmark

It doesn't take much to wreck a bearing with a bad crank... It could be off just a little bit and it will eventually destroy the bearing... If it is running fine, I wouldnt worry about it.. 4 gallons is getting into major rebuild territory anyway.

checked the crank again ,stripped the engine had a look , and their is a slight twist in it.
when u say major rebuild ur talking about a piston , liner and conrod possiblely front and rear bearings.. my lhs only sells half gallons so i meant to say 2 gallons.

thanks for info much appreciated,
regards madmark.

Without getting a new head, your rebuild will cost about $50 US... While your at it, go with the .18 conversion...same price and a bit more power fromn what I'm told....... This price should also include the bearings front and rear....

might do that when i fix my truck after last weekend , the throttle servo arm came off ,truck took off flat out till it hit a car [parked] followed by the front of a house.
well it proves one thing for me , tough truck only broke rear drive shaft.
when its fixed i plan on first new bearings and crank ,drive it till it needs new piston and sleevr then do the new .18 conversion.
let me know if u do the changes and how u get on

cheers for info
madmark

hi, i also have that sort of problem, the fuel leaks out so bad (at the bearings by the flywheel) that the engine dosent even fire, there is some play on the crankshaft that it goes back and forth although it isnt bent. i put instant gasket by the carb and backplate so the fuel is definatly not leaking from there.

that what idid as well ,high temp gasket sealer on carb and anywhere else that it could leak.
check ur crank again i thought mine was o.k. too but after inspecting it very carefully i saw the bend not much but enough too damage bearing. [cenracer1 remembers a post some time ago from cen about this]
i think that back and forth play is o.k [ i have that aswell the flywheel can move back or firth around 2mm] because it is the bearing that seals it not the fact that the flywheel is tight against the engine case/front bearing , so unless cen or anyone else who knows different [if they do they might respond] i presume i have the righjt idea.
and u say it wont start, the bearing must be very bad , try getting a new fr bearing should'nt cost much, but as cenracer1 pointed out to me ,if ur crank is bent then u'll be faceing same problem again down the road. have agood look at the crank while rotating the engine [slowly] ,place it on a bench while doing this see if the end of crank is moving up or down ,use the table as a line of sight if u get what i mean , if its a high mileage engine maybe its just simply time for rebuilding ur engine.