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Discussion Starter · #1 ·
1) Is there a link to a jet chart to show both recommend oem jets and which big/small size jets go together?

2) What is the OEM suggested small size jet for a terra pro 350 (or big bear 350)

My other issue if one of the five safety senors when I engage PTO is killing engine, for now I want to fix this carb issue first.

ok here the whole story for anyone who wants background information. I have a 89 yamaha terra pro with pto driven bushhog (bought new specifically for the pto) the last few years I don't use it every week like I used to and I got tied of cleaning the old carb with a bust float ear so I bought a new carb for a 350 big bear swapped some of the specialty parts and works pretty good, except after about a hour running the engine would be hot hard to start unless you et cool down (to me this says running lean) . I opened the replacement carb today. The original carb has a 115 big jet but I can't small jet out. the new carb has no numbers NONE on jets but the hole is bigger I'd "guess" maybe 130-135 (larger then my Old carb had in it) My fuel metering screw is currently set at about 4 -4.25 turns out so way to much and I'd think should be running rich not lean ................ my best guess is that low end jet needs to be replaced with a larger size. Does anyone have some advice or opinions ? or link to jet sizing chart?
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letting the carb cool down has no correlation to it starting hard.
are you using a battery elec start?
check the batt voltage before starting, and while its running, report back please.

does it just die after an hour or no?

for a 89 big bear 350, main jet is 120.
pilot is .45

a good starting point for the pilot screw is 2 turns out.

make sure the float is adjusted properly
when was the last time the plug was replaced?

you can find part numbers here
 

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Discussion Starter · #3 ·
letting the carb cool down has no correlation to it starting hard. --------- just trying to give as much info as possible about what it is doing , I just figured it was running lean.

are you using a battery elec start? ---------- Yes I am handicapped and have to use the elec start but it does have a kick starter I just can't use that . but the Elec starter spins over good.

check the batt voltage before starting, and while its running, report back please. ---------- I tried replacing battery to so its also new. it isn't a hard start where it just doesn't want to turn over it spins over fast just not starting. I can't currently check cuas eI just pulled carb out and apart to order new jets , but I'm confident it's not battery since both old weak battery and new hot battery did same thing.

does it just die after an hour or no? ------------ sometimes but not always and when it does it kinda that low ideal while sitting there and dies but most time I shut off for some reason then tr to restart

make sure the float is adjusted properly -------------- well to be honest I don't know how to adjust the plastic float the needle hangs on the float and hole is clear past that not sure what to do with it

when was the last time the plug was replaced? -------- roughly about a year ago at same time I replaced the carb and battery just before this issue started, probably has 2-3 hour total run time. I will replace it again to when put carb back .
 

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Discussion Starter · #5 ·
ok thanks, I'll check the voltage regulator when I get it running agian
 
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