Hello there, i am wondering about a rattle noise in the engine (i think). I have an sks 850 146. It runs perfectly fine just that when you let off the gas from high rpms it makes some kind of rattling/knocking noise in the engine.
Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
My ski tips rattle on mine. I’d check there just to see.
Post a vid so we can all hear it. Its hard to diagnose from words but it was a very good description!Hello there, i am wondering about a rattle noise in the engine (i think). I have an sks 850 146. It runs perfectly fine just that when you let off the gas from high rpms it makes some kind of rattling/knocking noise in the engine.
Exhaust valves?
I have mentioned this several times on different threads.
You you own a high performance 2 stroke motor you owe it to yourself and anyone you talk with about the performance of your motor to buy a leak down tester.
They are very inexpensive
It's really not fair to even ask questions about your motor unless you know the cylinder sealing ability..... ( compression tests do not work the same way )
Depending on your experience level using a leak down tester ( you must also have a small air compressor ) ....... In under 20 minutes you will know if your motor is in great to poor condition by % of leakage.
And what's more important...... If you do this procedure several times you will see 1 or 3 very important things as you put more miles on your sled.
Your leak down tests over a short period of time with show either....
1- the motor leak % is getting lower.
2- the motor leak % is getting higher
3- the motor leak % is staying the same
If the leak % goes up form one test to another the top-end is junk.
There is really no run abilities questions that can be fairly asked without knowing your motors leak down numbers.
People have been asking where you can get a decent leak down tester, my first one was from a snap on dealer over 35 years ago and I believe it was just under $250 dollars.
We have since purchased several new ones and tested them against each other.
We ordered fair amount of them to hopefully put on our website yet this week.
Ours will come with detailed instructions how to perform this test correctly which most leak down tester fail to supply in the kits.
Or you can buy one from your local Snap on, MAC dealer, Matco dealer.... And so on.
All performance problems cannot effectively be trouble-shot without a leak down test.
Dan
What do you like to see for % leak, whats average? And when would you repair, just when it goes up or you have a number?
Polaris historically was 5%. That is where I believe max should be on a 2 stroke..