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Stator cover and gas smell

Posted: 10:54 am Mar 28 2018
by Kngnthn76
I removed my stator cover and the smell of gas was very strong. I didn't see anything in there but the flywheel is in the way. Would this be a crank seal issue?

Re: Stator cover and gas smell

Posted: 11:28 am Mar 28 2018
by Julien D
Almost certainly. Unfortunately the cases must be split to get to the seals. If you grab the flywheel, does it have any up down left right play? Normally bearing slop is what causes the seal to fail.

Stator cover and gas smell

Posted: 11:52 am Mar 28 2018
by pumpguy
There have also been cases of fuel leakage along the wires and through the grommet. Check the area around where the wires exit the stator housing to see if this area is dry or not.

Re: Stator cover and gas smell

Posted: 01:43 pm Mar 28 2018
by kdx633
many kdx's have porosity in the casting behind the stator.Jeff Fredette even addresses this in his care and maintenance video.Remove the stator and carefully inspect the path of the leakage,The source will be obvious.

Re: Stator cover and gas smell

Posted: 05:00 pm Mar 28 2018
by Kngnthn76
Julien D wrote:Almost certainly. Unfortunately the cases must be split to get to the seals. If you grab the flywheel, does it have any up down left right play? Normally bearing slop is what causes the seal to fail.

No side to side but maybe a little up and down play.

Re: Stator cover and gas smell

Posted: 05:30 pm Mar 28 2018
by Timtee
Kngnthn76 wrote:No side to side but maybe a little up and down play.

Not good. Time to split the cases.

Re: Stator cover and gas smell

Posted: 05:34 pm Mar 28 2018
by Kngnthn76
I was afraid of that. Looks like a full rebuild is coming. At least it is running and not locked up.

Re: Stator cover and gas smell

Posted: 07:07 pm Mar 28 2018
by Kngnthn76
Anyone used Ken O'Conner for crank rebuilds and jug replating?

Stator cover and gas smell

Posted: 07:54 pm Mar 28 2018
by SS109
Never used Ken. I've always used Andrew Cooksey of Cooksey Crank for my cranks and Millenium for my plating. There is really only a couple of places in the USA that do the plating and everyone else just subcontracts the work to one of them.

Re: Stator cover and gas smell

Posted: 07:56 pm Mar 28 2018
by KDXGarage
You MIGHT want to do a pressure test and vacuum test before splitting the cases.

Re: Stator cover and gas smell

Posted: 08:01 pm Mar 28 2018
by Kngnthn76
Jason wrote:You MIGHT want to do a pressure test and vacuum test before splitting the cases.
Never done that before. What is needed to perform the tests?

Re: Stator cover and gas smell

Posted: 08:13 pm Mar 28 2018
by KDXGarage
Kngnthn76 wrote:
Jason wrote:You MIGHT want to do a pressure test and vacuum test before splitting the cases.
Never done that before. What is needed to perform the tests?
I can't stop myself...a pressure / vacuum tester. :kick: SORRY. :mrgreen: :razz:

Some have made a home made tester. Here's a pic of the real deal.

https://www.cyclegear.com/accessories/m ... OxEALw_wcB

Stator cover and gas smell

Posted: 09:04 pm Mar 28 2018
by John_S
Becuase of the cost of the real deal I went to ace hardware. This one cost me $40-50 and the bulb is $5 from Amazon. You could also use a schrader valve instead of the bulb but make sure you don't use compressed air to pump it and remove the air pump when you do test it incase the pump itself loses pressure. This is for pressure only. I've never vacuum tested one but need to figure that out for the future.

In addition to this I got a 1 3/4" expansion plug from the auto parts store to block off the exhaust port.
You pump it up to 7psi for 7minutes. It's important to do before tear down and before the exhaust and carb goes back on a rebuilt top or bottom end. I source the air leak until it's zero loss at 7 minutes (or however long I leave it there). I've read that 1 psi loss is acceptable but I don't know for sure.

If you have any questions about making one or doing the test feel free to ask.

Re: Stator cover and gas smell

Posted: 09:10 pm Mar 28 2018
by Timtee
Pressure test isnt going to do anything for the play in the crank bearings.

Re: Stator cover and gas smell

Posted: 09:17 pm Mar 28 2018
by John_S
Check out this article on leak down testing and air leaks. At the end of the article they say they offer the kit for $39. I also made an all pvc one for cheaper than the brass version but would've paid $39 from Klemm if I knew they offered it.

http://www.klemmvintage.com/airleaks.htm

Re: Stator cover and gas smell

Posted: 09:21 pm Mar 28 2018
by John_S
Timtee wrote:Pressure test isnt going to do anything for the play in the crank bearings.
The before and after test is to see if it was leaking before you take it apart so you know to double check that area when it's back together. Definitely not going to fix crank bearings.

Compression and leak down tests on the engine thats getting ready to be rebuilt gives you baseline numbers.

Re: Stator cover and gas smell

Posted: 09:24 pm Mar 28 2018
by KDXGarage
Timtee wrote:Pressure test isnt going to do anything for the play in the crank bearings.
Who said it was?? :hmm:

Re: Stator cover and gas smell

Posted: 05:46 am Mar 29 2018
by Timtee
The cases need to be split to fix the bearings. No need to waste time testing the worn engine.

It is best practice to test the rebuilt engine - but it isnt a necessity. Most peole dont and are fine.

Re: Stator cover and gas smell

Posted: 07:07 am Mar 29 2018
by KDXGarage
Kngnthn76 wrote:
Julien D wrote:Almost certainly. Unfortunately the cases must be split to get to the seals. If you grab the flywheel, does it have any up down left right play? Normally bearing slop is what causes the seal to fail.

No side to side but maybe a little up and down play.
How does a main bearing have this?? How can it be up and down and not side to side??

Re: Stator cover and gas smell

Posted: 08:01 am Mar 29 2018
by david
Jason wrote:
Kngnthn76 wrote:
Julien D wrote:Almost certainly. Unfortunately the cases must be split to get to the seals. If you grab the flywheel, does it have any up down left right play? Normally bearing slop is what causes the seal to fail.

No side to side but maybe a little up and down play.
How does a main bearing have this?? How can it be up and down and not side to side??
Because when you are checking side to side, you are testing both bearings at the same time. If one is good, it will hold the crank in place. When you are checking up/down play, you are only testing the bearing that you are prying on (in this case, the stator side).