Gt380 high idle after refurb

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Fula28

Gt380 high idle after refurb

Post by Fula28 »

So my rebuilt carbs are high idle/ Only have Clymer book for ref? Anyhoo I've ultrasonically cleaned them and rebuilt with new floats /and full strip.I have decided to swap the dust boots and slide bellows today, So I believe there is an air leak at bellows as motor dies if you spray it whilst running, So I need to Sync them again after boot swap. Any tips for bench synching (idle turned right off I believe)? As book shows only one dot on slide (rh side) carb with brass blank removed! Just always best to ask Questions before I delve in for sure .
May have a stuck centre oil Nrv valve too as it smokes like a train from centre pot when you Caine it.
Cheers fula.
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slosher
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Re: Gt380 high idle after refurb

Post by slosher »

Fula28 wrote: As book shows only one dot on slide (rh side) carb with brass blank removed!
Welcome Fula that is for setting correct oil pump feed if it's anything like the 550 turn the throttle until the dot is in the uppermost of the the inspection hole and the two lines match up adjust your oil pump cable if need be.

Cheers Dave
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Fula28

Re: Gt380 high idle after refurb

Post by Fula28 »

Thanks Slosher, yes oil pump is set correct, I removed the carbs today to swap the boots,and dust covers but it ended badly, As one of the alloy bell cranks broke that the pivot shaft goes through! Gutted as it was last one to reboot ahhh. So after a replacement for that now, then try work out best way to sync up carbs anyone have any tips?? Carbs on bench.oh and why is there so many oil pipes one supply? And one return for each pot thought it was total loss system?
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BAZ
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Re: Gt380 high idle after refurb

Post by BAZ »

the best way to sync the carbs is with a flow meter on the rear of the carb. I have new lifts in stock but are very pricey...
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Alan H
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Re: Gt380 high idle after refurb

Post by Alan H »

Fula28 wrote:oh and why is there so many oil pipes one supply?
Because there's only 1 pump and lots of places the oil needs to go.
And one return for each pot thought it was total loss system?
It is. The other pipes are called SRIS.
Proof that four strokes are over complicated
stupot
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Re: Gt380 high idle after refurb

Post by stupot »

Talking to yourself again ?
everyones a winner
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Alan H
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Re: Gt380 high idle after refurb

Post by Alan H »

stupot wrote:Talking to yourself again ?
No. Read the post.
Proof that four strokes are over complicated
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Fula28

Re: Gt380 high idle after refurb

Post by Fula28 »

Thanks appreciate the explaination, Sris new one on me for sure! Just one thing the Nrv valves that stick and cause smoking issues, Are they the little 8mm banjo bolts at each hose end? Can I remove them an test them if this is case, Bang em in the Sonic bath will free up any nastyness.Learning lots thanks :D
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Alan H
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Re: Gt380 high idle after refurb

Post by Alan H »

There's been lots posted on oil lines, non return valves and SRIS systems. Top left of the screen are 3 horizontal lines, click on that and a drop down appears. Click search and type what you are searching for. Lot easier than explaining it all again!

Just one important thing - DO NOT BLOW COMPRESSED AIR DOWN THE OIL LINES OR YOU WILL KNACK THE BALL, SEAT AND SPRING OF THE NR VALVE.

Take the oil spider off and hang it up with the nr valves 'down' leakers will be seen by next morning.
Proof that four strokes are over complicated
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PaulD738
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Re: Gt380 high idle after refurb

Post by PaulD738 »

Alan H wrote:
Take the oily spider off and hang it up with the nr valves 'down' leakers will be seen by next morning.
Oily spider? if you used that pink feather duster for its intended purpose instead of a sex toy you wouldn’t have oily spiders in yer garage :shock: :shock: :lol:
They're rubbish them Jap bikes lad they won't last five minutes! you want to get yourself a nice Royal Enfield!
A quote from my old dad 8-)

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