leak down test

[liminlime_2005]

i performed a leak down test and had a very small leak. i sprayed all around the gaskets of head, jug, exhaust port and intake with soapy water but i couldnt find any leaks, it was kinda hard to get a really good look with the engine still mounted. could my crank seals be bad or something else and how could i check?

 

[mike2225]

if it was clutch side crank seal, you would really be smoking and low all the time on case fluid. if it was mag side you would be running really lean.

 

[Awk08]

how much psi and how long was it holding it ?????
7psi for like 5 - 10 minutes is sufficiant
any more psi or longer and it will leak off

 

[liminlime_2005]

i pumped it to 10 psi and takes like 5 mins to leak completely out

 

[liminlime_2005]

im not sure witch side it is but i noticed that there is lots of oil in my exhaust. enough in it that when i take the head pipe off and hold it up oil comes out, like a couple table spoons. could that be rich jet settings that will cause oily exhaust?

 

[liminlime_2005]

it doesnt seam to be running lean, if anything its running like sh*t. it does seem to smoke pretty good but not real bad and when i put my smallest jet in the carb just about all the smoke is cleared.

 

[royalt67]

Crank seals are cheap and medium-easy to install. Good insurance. Both of mine leaked.

 

[phragle]

leaking to zero in 5 minutes is bad. you now know why your bike is running like chit. pull the motor out of the bike. CLEAN the motor, not knock the big mud junks off, but really clean it. next pull the clutch cover and primary gear as well as the stator cover, flywheel and stator. clean the surface of the main seals. now inflate to 7 psi and put dishsoap and water in a spray bottle. spray the main seal and spray the cases where they join together in the center.

 

[royalt67]

When my right-side seal leaked, I could hear the air escaping from the vent tube. (Big leak)

 

[liminlime_2005]

i dont have a place to store the engine when apart so i would have to get all parts and tools necesary to perform the job. whats required?

 

[liminlime_2005]

i was a bit discouraged about the ol blasty when i seen that gauge slowly going down. i dont have anywhere to store the engine when apart. what tools and parts are required for the job?



oops thought my message didnt send ^^^

 

[Blasterdude27]

i dont have a place to store the engine when apart so i would have to get all parts and tools necesary to perform the job. whats required?

Your going to need a clutch holder.
If I remeber right you pull off the clutch, then remove the counter balancer gear and drive gear thats on the crank. The seals are directly behind the gear, pull them out replace them and put it back together. A word of advise; make sure the dots on the balancer gear and crank gear line up perfectly, if they don't you'll be riding a giant vibrator.

 

[royalt67]

That was a fantastic way to check it that phragle gave, but like I said, if it was me I would just change em and be done with it. They can be changed without removing the motor, although working on a bench is nice.

Left side: remove side cover, flywheel and stator. You will need a flywheel puller, 15 bucks at a cycle shop or ebay. Impact wrench and air is nice to have. If not you will need a way to hold the flywheel too. A large strap wrench or an actual flywheel holding tool. The seal will pry out easily enough with an old screwdriver or small prybar. Lube the new seal with grease, lips and outer edge, and tap it back in. I used a large deep socket that fit over the crank. You just want to get it flush with the case. It is critical that you get the flywheel nut TIGHT or it will come off later. NO LOCTITE.

Right side: remove right footpeg, drain oil, remover kicker and side cover. Remove clutch assy and then crank gear. Seal removal and replacement is similar. On this side I had to hold the seal and kind of tap around the edge with a large punch and hammer VERY carefully, a little at a time, all the way around the perimeter. Again, you need air tools or something to hold the clutch to get the nut off.

As always, read the manual and get familiar with what things look like and pay attention so you get it back together correctly. The clutch pressure plate only goes on one way.

www.rydindirty.com/blastermanual.pdf

 

[royalt67]

Your going to need a clutch holder.
If I remeber right you pull off the clutch, then remove the counter balancer gear and drive gear thats on the crank. The seals are directly behind the gear, pull them out replace them and put it back together. A word of advise; make sure the dots on the balancer gear and crank gear line up perfectly, if they don't you'll be riding a giant vibrator.

Good point..................

 

[brandoz28]

well......i build my stuff on coffee tables and kitchen tables so i'm sure there's SOMEWHERE you can put it

 

[scotj77]

i wander if you used a small baloon and clamped it on the vent tube that it would start to inflate if the leak was on the clutch side crank seal. anyone ever tried that?

 

[phragle]

if you dont have a clutch holder, you can stick a penny in the primary gear. pennys are soft and shouldnt hurt anything, allthough this is only recommended as a last ditch effort.

 

[phragle]

and dont great the OUTSIDE edge of the seal. you want it and the mating surface clean and grease/oil free or the seal can work its way out.

 

[royalt67]

and dont great the OUTSIDE edge of the seal. you want it and the mating surface clean and grease/oil free or the seal can work its way out.

Your word works for me phragle. I was just told differently by a diff bike mechanic. That's why i mentioned it. Of course on the right side it shouldn't matter since there is a retainer.

 

[royalt67]

i wander if you used a small baloon and clamped it on the vent tube that it would start to inflate if the leak was on the clutch side crank seal. anyone ever tried that?

No, but it might blow bubbles if the tube was put in soap solution.