davpig
Newbie
First, I ride my rx1 today. I push on the accelerator and at the same moment I heard PAWWW! After that, the engine run on 3cyl and I lost a bit of oil (not much!) from the air carburator hose... The engine does not slam. I checked the spark plug and all is ok... The cylinder 2 don't draw air from the airbox... So, probably a piston is blown or a valve is burned. So my question, is it possible I have a oil leaking because a valve is burned?!?!?
Thank you!
Thank you!
MNBlizzard
Expert
Oil out the carburetor??? Not fuel? Right away I suspected dirty carbs, but the oil is throwing me...
do a compression/leak down test of that cylinder.... I put my money on hole in piston, whats the spark plug look like???
davpig
Newbie
the spark plug on the cylinder who have problem look like the 3 other... it doesnt have oil on it and doesnt have gaz not burned on it...
Len Todd
TY 4 Stroke God
I like to rule out all the common stuff first.
Have you checked the wiring to the coil? Did you test the coil? When was the last time you cleaned the carbs? Are you using fresh fuel? Have you pulled the carb and looked for a problem inside it? Have you drained the oil and ran it through a cloth looking for metal?
The compression check will tell you if you burned a hole in the piston. If there is a hole in the piston, then one has to ask "why?," which brings you right back to the carb cleaning, etc.
Have you checked the wiring to the coil? Did you test the coil? When was the last time you cleaned the carbs? Are you using fresh fuel? Have you pulled the carb and looked for a problem inside it? Have you drained the oil and ran it through a cloth looking for metal?
The compression check will tell you if you burned a hole in the piston. If there is a hole in the piston, then one has to ask "why?," which brings you right back to the carb cleaning, etc.
davpig said:
Well I have blown 2 of them and they don't make any noise other than a burp and then start running rough untill all the oil is gone and then the remaining cylinders burn the rod bearings. My last one threw 2 rods and still ran. If your plug is out use a screw driver in the cylinder and hit the starter to see if 1st the piston is moving up and down.
dropped valves could allow oil to enter through from the head past the guides hole in a piston could allow the crank case pressure to push oil up from below and out through the valve. Pressure test won't give you the whole story bcause a broke or stuck valve and a hole in a piston will leave you with no compression. I have seen more than 10 of htese with bad valves and at least that many with thrown rods.
davpig
Newbie
I will open it next week to see what happens... I hope this is a valve... Thank you for your help all!!!
So why are the valves/pistions/rods ect failing yamadog??
just like anything else nothing is perfect. These motors are not as bullet proof as we want to think. I can probably get my hands on more than 10 that failed locally. Both of mine were so catastrofic it's hard to put a finger on the cause.
One was stock 03 with 6,000ish miles. I change the filters 2 times a season and oil both times using only Yama lube. Never overreved the motor. 2nd was a 06 Apex motor rebuilt with 900 miles on it because it cam out of a totalled sled and sat in the salvage yard with no air box. I had it built by Pat Hauck and we put a stroker cam in it to 1100 cc's. I put 3000+ miles on it in 2 months and it blew. Threw 2 rods with a hole the size of an orange in the block.
One was stock 03 with 6,000ish miles. I change the filters 2 times a season and oil both times using only Yama lube. Never overreved the motor. 2nd was a 06 Apex motor rebuilt with 900 miles on it because it cam out of a totalled sled and sat in the salvage yard with no air box. I had it built by Pat Hauck and we put a stroker cam in it to 1100 cc's. I put 3000+ miles on it in 2 months and it blew. Threw 2 rods with a hole the size of an orange in the block.
