Leak down percentage

[OB_jim p]

I read about the mods people are performing on their busa, but has anyone done a leakdown. I will do one @ 2500 miles, just interested to see numbers from someone else.

 

[OB_Dingo]

Excuse my ignorance . . . but what's a leakdown?

 

[OB_maui]

Leak down is similar to a compression check, but you read cylinder seal as a percentage of leak down, i.e. 97% would indicate a 3% leak past the rings and such.

 

[OB_Aussie]

It would be good to include the run-in procedure and oil/s used. Also usage ie weekend, racing or day to day commute.

I would be interested in the results.
Aussie Abroad

 

[OB_Dingo]

I must spend too much time interpreting bits . . . I'm not a pro when it comes to mechanics. Thanks for the explanantion

 

[OB_maui]

Dingo

If you decide to pick up a leak down gauge, make sure you get a dual gauge version instead of the single. You will also need access to an air compressor capable of at least 100psi (you can do it at 50psi, but that doubles the math skill you needed) The leak down test is very easy to do and can show you more about what's going on with your engine as it is unaffected by cam changes or cylinder pressure. Also, when you do a leak down, listen to your intake, and exhaust, if you hear air escaping, it would indicate a leak at the valve.

 

[OB_maui]

If you want a leak down tester (dual gauge) you can get one from jeg's, part # 892-8015, 1-800-345-4545 $63.99

[This message has been edited by maui (edited 11 October 1999).]

 

[OB_Earl]

Have not done a leak down yet but----compression check at 1500miles warm 1-218 / 2-218 / 3-220 / and 4-218. I consider this great, consistant ring seating.

 

[OB_jim p]

When the the coolant hose blew off the R1 and it overheated the first thing i did the next day was check the leak down. All cyls were in the 3 to 4 % range, which made me feel much better.