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Leak Down Test

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First of want to thank everyone with the help I recieved on my rebuild. Ran into a major problem but everything worked out for the best. I have put about 10 hrs on my 2005 yz 250 since my rebuild. So far so good. No pinging or detonation which was the probable cause of my initial blow up. Been running 100octane low lead from my local airport at 3.85 a gallon. Have her jetted just right, very crisp throughout, very little smoke at operating temp and NO spooge. Here is my problem. I have changed my tranny fluid twice now and both times only drained about half of what I put in which was 24 oz. Do not have any leaks that I can find so I will assume I am burning it. It seems if I was though it would smoke a bit more or even foul a plug maybe? Have decided I would like to do a leakdown test on my tranny and need to know how to go about it. I tried a search with several different parameters and came up short. Any ideas or input? thanks.

DJ

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This is the case which was repaired on the cluch side?

I would be thinking either the welds are porous or the seal bore is off centre.

You do a leak down test on the cylinder, not the transmission. It will tell you what you want to know. Have a look in the honda section there is a sticky on how to make a leak down tester.

Alternatively you could pull the side cover off, spray the suspect area with soapy water and watch for air bubbles as you turn the motor over.

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Thanks for the reply mister pimp! Found the issue, it was a super small hole in the weld that went from crank side to clutch side. Got her all fixed up this evening. Good idea on the soapy water trick, should have tried that when I had her broken down. I am suprised at how well and strong she has been running while I was burning the oil. If my jetting seemed good before I suppose it could go lean now? I will find out tomorrow. One would think it would smoke alot at the rate I went through the tranny oil. In about 4 hours of time burned almost HALF of my tranny oil!

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theres no oil leaking out anywhere on the engine? if your putting 24oz in and only draining out 12 i think it kinda impossible to be burning all that and showing no signs of it. Do you drain your oil after you get it warm a little so the oil isnt so thick and comes out easier? Have you actually measured the drained oil so you know for sure your only draining 12oz out? Burning 12oz of oil in one interval would be alot!! How often are you talking between oil changes?

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Have put 10 hrs or so +-1 hr. have changed my opil twice. Measured it both times. Half of what I put in. Going riding now to see if I fixed the problem. Have my fingers crossed!

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Thanks for the reply mister pimp! Found the issue, it was a super small hole in the weld that went from crank side to clutch side. Got her all fixed up this evening. Good idea on the soapy water trick, should have tried that when I had her broken down. I am suprised at how well and strong she has been running while I was burning the oil. If my jetting seemed good before I suppose it could go lean now? I will find out tomorrow. One would think it would smoke alot at the rate I went through the tranny oil. In about 4 hours of time burned almost HALF of my tranny oil!

No worries, glad to be of help.

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