Gt380 high idle after refurb

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Alan H
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Location: Wombwell, Republic of South Yorkshire

Re: Gt380 high idle after refurb

Post by Alan H »

As I'm not a truck driver Paul. I don't need or use sex toys.
Proof that four strokes are over complicated
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Fula28

Re: Gt380 high idle after refurb

Post by Fula28 »

Are oil valves in these round banjo fittings ? Bolts are hollow for sure.just want to check there not stuck open,Before I fit the carbs (Again) Or do I need to pull the octopus and check there, for the ball valves.
Cannot find any pictures or diagram of the oil system in my book.?

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barney01
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Location: Prestatyn.Wales

Re: Gt380 high idle after refurb

Post by barney01 »

The valves are indeed in the banjo. There is a ball which is held shut by a small spring which is forced back by the pump pressure. When the engine stops the ball seals the valve to prevent oil from the tank entering the engine. The way to test the valves is to remove the pump and spider. Fill all the lines with oil using an oil can or syringe. Then hang the spider up banjos down over night. The lines should be still full of oil in the morning. If not the banjo is faulty.
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NO SMOKE .......NO POKE
crazy4557
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Joined: Sat Dec 07, 2013 1:24 pm
Location: Lymington, Hampshire

Re: Gt380 high idle after refurb

Post by crazy4557 »

That's a really helpful explanation for us numpty's. Can you get spare springs etc for these if needed and if so what's the most common 'worn out' parts? (Apart from most of us on here) :lol:
1976 GT550A in black
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Fula28

Re: Gt380 high idle after refurb

Post by Fula28 »

Ta Barney this is great gen, appreciate it! I shall wip out the hoses, and test for sure,But I'm also positive they will leak. Cheers Again . ;)
barney01
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Location: Prestatyn.Wales

Re: Gt380 high idle after refurb

Post by barney01 »

https://hard-to-find-parts.de/epages/af ... -31031/set"
look under suzuki oil lines
You can also buy the banjos complete to attach on the end here
https://www.cmsnl.com/products/valve-ch ... -KQLjnLc0N
I know it says Kwak but they have been used on GT very successfully.
NO SMOKE .......NO POKE
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Fula28

Re: Gt380 high idle after refurb

Post by Fula28 »

So flushed oil manifold , and left it oiled and hung up fir rest of week, We will see what happens . I am concerned that the Extra smoke maybe another issue (crank seal ) or burning gearbox oil ,I have no proof as yet but just a little worried.



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barney01
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Joined: Wed Sep 26, 2012 7:33 pm
Location: Prestatyn.Wales

Re: Gt380 high idle after refurb

Post by barney01 »

Check your SRIS valves at the front of the engine . a valve that is stuck in the closed position can be the cause of exhaust smoking excessively.
NO SMOKE .......NO POKE
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Fula28

Re: Gt380 high idle after refurb

Post by Fula28 »

Front if engine Barney?! Nothing there that I see, only the banjo valves under the inlet stubs! Is that the ones your thinking of? They have been checked and seal and none leak? Hung them up for 2days with oil In lines, then if you use a syringe it cracks and flows oil ok , No dripping or weeping ? after a reassembly of oil pipes and Carbs again, She fired up Smokes so badly cannot see house or road as soon as you open it up.. Poof Smoke did 20miles today and it did clear a little but not sure it was better, Even at idle plenty of smoke, And it won't idle below 1250- 1300rpm no mater What i try,
Can this be Crank seals? Maybe. Only 651miles from new on this bike. Was in private collection before it ended up with me. ;)
barney01
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Location: Prestatyn.Wales

Re: Gt380 high idle after refurb

Post by barney01 »

Sorry the GT380 ditched the SRIS so possibly not fitted to your bike. The good news is your oil feed banjo's appear to be working correctly. Now to address the smoking problem. What oil are you using? Have you slackened off the throttle adjuster by the twistgrip on the handlebars.? Couple of other things you didn't rebuild using Keyster jets did you? And i dont see the carb manual link on this post so here you go http://www.3cyl.com/mraxl/gt/manuals/su ... /cover.htm
Just a thought. You haven't taken the oil pump arm off have you? It is possible to put it back 180 degrees out
Here is another theory: if smoke is pouring out of the middle pot only, it could be a sticking float on that carb which would account for the high idle as the pot is running lean revs increase. Not enough fuel but plenty of oil means lots of smoke.
NO SMOKE .......NO POKE
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