I think I blew a ring...

[aaronsoccer4]

Story​

I had my 260 jet in disreagarding what you guys said and doing what the guy from the local shop said and I pulled out of my drive way and it back fired a few times then a big one and died so at first I was like shi*, now it wont start so I took the head off and piston was ok but I think I blew a ring

Question​

What would the cylinder walls look like if I bew a ring, I did a leakdown with my leakdown tester made for cars and it said 100% leakage with 75 psi going through it so I took of the top end and the piston was fine but the walls where the two edges of the exhaust port is had very faint wear marks

 

[j mcq37]

Leak down test should be an air test between five and seven psi. A blown ring will leave a burnt look on the side of the piston past the rings called blow by. If you did a compression test and it registered 75 thats bad compression. The exhaust side of the piston is exposed to the most heat because of exiting exhaust gases.

 

[aaronsoccer4]

just did a compression test and it holds 120 psi

 

[darederek]

if you did a leakdown with 75 psi i would bet ur crank seals just got blown out. you use like 7 psi man

 

[aaronsoccer4]

if they did would that stop it from starting

 

[darederek]

no but it would either rev up and run lean or smoke really bad and burn tranny oil depending on the side

 

[Larry's Shee]

if they did would that stop it from starting

Very possible, try it again with only 6-7 psi. Also on your comp test you said "it held" 125 psi. what did you mean by that, or what procedure were you using.?

 

[aaronsoccer4]

I took off the gas tank plugged in the compression tester to the spark plug hole and kicked it three times and it stayed at 120 psi

 

[slickerthanyou]

120 is good but usually it takes more than 3 kick you should kick it, while holding throttle wide open at least 10 times or until the needle stops going up.

As Far as a leaktest, as said 7-10PSI MAX. Let it sit for 5-7minutes and you shouldn't loose more than 1 psi!

Please don't put 75PSI in your motor! here is a link for proper leak testing a blaster motor. http://www.blasterforum.com/do-yourself-20/build-use-leakdown-tester-10663/

 

[aaronsoccer4]

when I did my leakdown test I did it from the spark plug because that was the adapter I had its made for a car and Im not even sure if it works but my compression was good so Im not to worried

 

[aaronsoccer4]

turned out to be a broken stock reed. I have a credit card on there until tom. morning when I can get new ones what should I get

 

[UncagedShadow]

just reeds, boyseen are great and wont break your bank account...

 

[Demo4o1]

wow all that to find out its reeds.... that happened to me too but i didnt take my top end off. took me awhile to find out i have a cracked Vf2 reed. FYI, if u blew ur ring. u'd know it. when kick starting it there would be NO compression and the piston would move up and down after u kick it way more times

 

[slickerthanyou]

when I did my leakdown test I did it from the spark plug because that was the adapter I had its made for a car and Im not even sure if it works but my compression was good so Im not to worried

Well did you block off the intake and the exhaust? If not that is why it didn't work.

Even though you found a broken reed, "good job" I'd still do a Proper leak test so ya don't fry that top end.

 

[j mcq37]

^^^^ x2 on the leak test