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I have no clue what happened, I was jetting the bike, and when I went to do my first plug chip and first test, it idles good, and then it sounds like it's not getting fuel, but its not, and the oil turned gray out of the blue
64259
 

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Looks like water ingress. How is the coolant level?

Can you do leak down tests? I would do one for the top end and one for the coolant system.
 

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Is that crankcase oil? How old is that oil?
 

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Looks like water ingress. How is the coolant level?

Can you do leak down tests? I would do one for the top end and one for the coolant system.
The coolant level is lower than average, and I'm not sure how to do a leak down test, cause I never had the need to
 

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The coolant level is lower than average, and I'm not sure how to do a leak down test, cause I never had the need to
You can do 3 different leak down test. One on the cylinder, one on the trans case, and one for the Radiator. I believe the cylinder/ Crankcase test is the more important of the 3, but I'd check everything of I were you. Do a search on "leak down test" on the forum. Lots of great ideas and procedures.
Good luck!
 

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You don't do a leak down on your trans case because it's vented, if it was sealed the pressure buildup would probably blow the center gasket out... You can get the parts you need to build a leak down tester from most hardware stores. I got my parts from home depot using a Sioux Chief natural gas line tester, some steel & pvc plumbing fittings & a rubber gutter downspout adapter. The gas tester I used has a Schrader valve so you can use a bicycle tire pump to pressurize your cases, just DO NOT used compressed air for this. If it holds 6psi for 6min your good to go. If not fill a spray bottle with soapy water & spray the gasket & seal areas associated with the crankcase & top end to find the leak. Also, 15 hours is enough time to turn your trans fluid gray... Hope this helps
 

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Discussion Starter #8
You don't do a leak down on your trans case because it's vented, if it was sealed the pressure buildup would probably blow the center gasket out... You can get the parts you need to build a leak down tester from most hardware stores. I got my parts from home depot using a Sioux Chief natural gas line tester, some steel & pvc plumbing fittings & a rubber gutter downspout adapter. The gas tester I used has a Schrader valve so you can use a bicycle tire pump to pressurize your cases, just DO NOT used compressed air for this. If it holds 6psi for 6min your good to go. If not fill a spray bottle with soapy water & spray the gasket & seal areas associated with the crankcase & top end to find the leak. Also, 15 hours is enough time to turn your trans fluid gray... Hope this helps
Okay, I'm going to do some leak down tests, I have an idea that it's the ceramic seal for the impeller, because everything on it is new except for that piece, mainly because I forgot about that part, and that part has been on the R since I can remember
 

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I have no clue what happened, I was jetting the bike, and when I went to do my first plug chip and first test, it idles good, and then it sounds like it's not getting fuel, but its not, and the oil turned gray out of the blue View attachment 64259
Okay, I'm going to do some leak down tests, I have an idea that it's the ceramic seal for the impeller, because everything on it is new except for that piece, mainly because I forgot about that part, and that part has been on the R since I can remember
Perform a full leak down of all three, this is how we do it at BDT; it insures no leaks.

1). Cylinder Water Jackets, WP Assy, Engine Hose; Pressure test from Inlet at WP/Clutch Cover through Outlet at top of head.

2). Cylinder; Exhaust Manifold, Head, o-rings, Base gasket(s), Intake reeds, Boot, Crankshaft Pocket & Main Seals; Plug up spark plug hole, plug up exhaust flange, pressure test with piston at BDC through Intake boot.

3). Transmission Pocket area, center case gasket, seals; plug up breather tube, pressure test through Oil Fill on Clutch cover

All three is the 'Best' practice, for all 3 use 4-6 PSI for 6-8 minutes with an acceptable loss of <1 psi. You do all three and pass, and you will have a 'sweet' running & jetting engine.

Carlos
 

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Perform a full leak down of all three, this is how we do it at BDT; it insures no leaks.

1). Cylinder Water Jackets, WP Assy, Engine Hose; Pressure test from Inlet at WP/Clutch Cover through Outlet at top of head.

2). Cylinder; Exhaust Manifold, Head, o-rings, Base gasket(s), Intake reeds, Boot, Crankshaft Pocket & Main Seals; Plug up spark plug hole, plug up exhaust flange, pressure test with piston at BDC through Intake boot.

3). Transmission Pocket area, center case gasket, seals; plug up breather tube, pressure test through Oil Fill on Clutch cover

All three is the 'Best' practice, for all 3 use 4-6 PSI for 6-8 minutes with an acceptable loss of <1 psi. You do all three and pass, and you will have a 'sweet' running & jetting engine.

Carlos
+1 on all 3 pressure tests, just did them on my R a few days ago. I always drained my transmission oil before doing the transmission test. Don't know if that's the correct way, just never liked oil blowing over EVERYTHING should a leak spring up!
 

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Perfect Chris....! :)

Carlos
Thanks Carlos!
We also did them on buddy's 89 yesterday, (doing a Banshee as we speak lol) then got the jetting right. Running really strong with a stock cylinder, some simple bolt-ons and a TRX-9B pipe.
Op, definitely do some leak down test, it's really simple once you do it a few times.. it's actually kind of fun! 🙃😁
 

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Discussion Starter #14
Thanks Carlos!
We also did them on buddy's 89 yesterday, (doing a Banshee as we speak lol) then got the jetting right. Running really strong with a stock cylinder, some simple bolt-ons and a TRX-9B pipe.
Op, definitely do some leak down test, it's really simple once you do it a few times.. it's actually kind of fun! 🙃😁
Will do, just in case, I bought a whole rebuild kit, thanks for the advice carlos, i swear BDT need to make a manual for all there tricks
 

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So I understand the reasoning behind the coolant system leak test and the cylinder/crankcase leak test, but I'm not sure how an air leak in the transmission can cause run ability issues? The transmission is supposed to be able to breathe and if it can't your transmission will create a hydraulic pressure. Said hydraulic pressure will most likely cause your seals to fail.
Again I routinely use leak tests for the cylinder and crankcase and understand the value, but do not and most likely will not test a transmission case that is designed to self regulate internal air pressure.
Please explain the benefits of leak testing the transmission? Seems to me that the probability of transmission seal failure is a great deterrent.
Loren
 

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If your asking about:
3). Transmission Pocket area, center case gasket, seals; plug up breather tube, pressure test through Oil Fill on Clutch cover

It has little to do with what you think, and a lot more to do with insuring their are no Oil Leaks once the customer receives the engine, and fills the transmission with Trans Oil.

Testing will assure the center case gasket and R & L case surfaces, clutch cover gasket & R case & Clutch cover surface are good. It also assures the Shift Shaft Seal, Kick Stater Shaft Seal, and WP Oil & MS assembly are good. At BDT we lap all surfaces, replace all seals & gaskets with OEM, yet a little 'double checking' is good for everyone.

Last thing you wan't is to ship engines cross country or world wide and have the customer inform you its dripping a tiny amount of transmission oil while sitting for extended periods of time...this very pressure test is one of three that insures a perfect BDT build.

Carlos
 
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