My Carburetors - oil seepage ?

  • 78kawltd
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My Carburetors - oil seepage ?

03 Mar 2020 10:02
#820209
KZriders : Can you offer any insight on the image ?
It sure looks like oil mixed with fuel leaking from the carb bowls.

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  • Scirocco
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Re: My Carburetors - oil seepage ?

03 Mar 2020 10:12 - 03 Mar 2020 10:13
#820210
No, it`s only fuel residues, (bowl gasket leaking).
Last edit: 03 Mar 2020 10:13 by Scirocco.

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  • 78kawltd
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Re: My Carburetors - oil seepage ?

03 Mar 2020 10:27
#820212
And so, it Looks like more work with bowl gaskets and Allen heads screws. We'll add to the list.
Just guessing, but most likely the seeping fuel residues (yes, it is oily to the touch ) within these old carbs may require additional carb rebuild work ?
She (78 kawasaki ltd) starts and runs good) .

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  • Mikaw
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Re: My Carburetors - oil seepage ?

03 Mar 2020 10:33
#820213
I’m not a big fan of allen head bolts on carbs. If you choose that route be careful not to over tighten them. Bad stuff can happen. The bowl,gaskets, and carb flanges do not respond well to high torque numbers
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  • 78kawltd
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Re: My Carburetors - oil seepage ?

03 Mar 2020 10:57
#820216
Thanks Scirroco and Mikaw. We'll proceed with caution.

For the oily seepage / residues from my posted image. I was also thinking potential valve intake issues . For example , an adjustment may be needed because of the age/ wear.... allowing oil to pass thru intake ? No?
Summary, No white smoke or real evidence. Again, She runs strong.

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Re: My Carburetors - oil seepage ?

03 Mar 2020 12:05 - 03 Mar 2020 13:42
#820219
Keyster made a rubber bowl gasket for Mikuni carburetor, Article No.: YFCG-27R
I use the same gasket multiple times (5 times bowl on and off) during my main jet setup with no leaks anymore until now.
I had change my bowl Phlilips (JIS) screws to SS Allen head screws during this process because it was much more easier/faster to do a jet change with the carbs on the bike.
It´s nothing wrong to use and tighten the Allen head screws. You only have to do the torque with two fingers only and a #4 bit between them.
Last edit: 03 Mar 2020 13:42 by Scirocco.

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  • KZB2 650
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Re: My Carburetors - oil seepage ?

03 Mar 2020 13:27
#820220
78kawltd wrote: Thanks Scirroco and Mikaw. We'll proceed with caution.

For the oily seepage / residues from my posted image. I was also thinking potential valve intake issues . For example , an adjustment may be needed because of the age/ wear.... allowing oil to pass thru intake ? No?
Summary, No white smoke or real evidence. Again, She runs strong.

Mine did the same thing when it leaked a few years back....... would have bet money there was oil in the gas but it was just the gas leaking by the old gaskets and taking some gasket material with it. Another fan of allens too just go easy like said.
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  • hardrockminer
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Re: My Carburetors - oil seepage ?

04 Mar 2020 05:20
#820257
The bowls will leak when fuel in the bowl is higher than the gasket. Leaving the bike on the side stand will allow fuel to ride high on one side, causing the leakage. Improperly adjusted floats will also do it. Leaky float valves are another possible source, but this problem usually results in leakage through the overflow tube.

The solutions? Leave your bike on the center stand when parked. Shut fuel off just before you get back from a ride to burn off some of the fuel in the float bowl. Adjust floats and check float valves.
I have several restored bikes along with a 2006 Goldwing with a sidecar. My wife has a 2019 Suzuki DR 650 for on and off road.

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  • 78kawltd
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Re: My Carburetors - oil seepage ?

04 Mar 2020 06:46
#820263
Hardrockminer, / and all. yes ,that would explain the angle of the residues, seepage, stain, etc. IE, left side only. Later, We'll plan probe deeper with the potential float problem...
With that task for the bowl work, I located an Allen Screw head supplier on Amazon;

Fullerkreg 0.7mm Pitch M4 x 16MM Socket Head Cap Screws, Allen S..
Stainless Steel.
100 pieces, / about $11. U$

So, I hope I 'm on track to move fwd. W/ her special care.

Thereafter , We'll source out the vendor for her Keyster bowl gaskets next. / VM26SS

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Re: My Carburetors - oil seepage ?

04 Mar 2020 07:22
#820271
We've come to the conclusion that the old fiber carb bowl gaskets are very slightly porous. Gas is thin stuff. After years of soaking, gas weeps & leaves that varnish residue. Adds to patina... :dry: Carb makers went to synthetic O-rings for good reason.

On Z1 carb gaskets, we use the thinnest possible wipe (just a sheen) of Permatex Ultra Black #22072. It releases cleanly & allows used gaskets to be reused many times.

Not a fan of Allen screws for float bowls; we've seen too many otherwise decent carb bodies Bubba'd by over-tightened Allen screws. A good JIS screwdriver can over-torque stock cross-head float bowl fasteners the way it is. We don't tinker with jets anyway, so it's not been an issue except when we have to deal with the aftermath of a PO using Allens.

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