| Author | Message | ||
     Northernyankee |
When doing my valve check last week I had a pitted Front Intake Cam. So the new Cam arrived today, I have gone through the FSM and the process doesn't look too bad to replace the Cam, but I was wondering if anybody has any tips or trick to make the process go easier. Any pointer or insight would be appreciated. Rob | ||
| Boogiman1981 |
Here did you order cam from? | ||
| Northernyankee |
I ordered it from Surdyke HD...they had the best price that I could find. | ||
| Northernyankee |
Man, I need to vent...lol. For anybody replacing a camshaft make sure the crank is locked at TDC of the compression stroke and not the exhaust stroke. Check, double check and triple check. I was doing the replacement today and it's really not that bad, but I made 2 mistakes luckily the second one saved me a bunch of headaches that would have occurred from the first one. Long story short I locked the crank at TDC of the Exhaust stroke and the only reason I realized it was because when I reinstalled the camshaft assembly I didn't have one of the intake followers in seated right and it caused me to have to pull the assembly back out and when I went to put the engine back at TDC I realized it was 180 degrees out of phase. Man small mistakes make things take way longer then planned. Glad I got my rant out...lol. | ||
| Pmjolly |
Wow. That could have really sucked if you tried to start it. | ||
| Nillaice |
why would that have really sucked? it is my understanding that these rotax engines are not 'interference motors' ... as far as the piston and valve train is concerned, the spark timing is 'wrong'. so i'm gonna say that it would run (like crap) on the front cylinder and the raw air/fuel mixture would be burning and backfiring out the rear header | ||
| Pmjolly |
I apologize. I probably shouldn't have said that. I had a Yamaha one time that had the cam timing so far off it was sucking in the exhaust and backfiring out the carb. Your post made me think of that. | ||
| Northernyankee |
I actually did have it at the compression TDC...it had been such a long day that I just wasn't thinking right. I just need more sleep...lol | ||
| Nillaice |
Pmjolly, sorry. i wasn't trying to come off sounding like a jerk. i agree that trying to start the bike with the rear valves 180 out would not have been a good thing. i just don't know why it would have been such sucky thing. you have nothing to apologise about. northernyankee, get some rest and then look at section 3.6 in the Service manual. if this helps any- i noted that when one cylinder is at TDC on the compression stroke; the other set of valves should have the match mark at about the 8 o'clock position (if the jug were vertical) | ||
| Zac4mac |
Pmjolly - I had a Yamaha 650 twin that I advanced one tooth on the cam chain. Ran like a bat outta hell but sometimes would blow one of the carbs out of the rubber boot when trying to kick over. Zack (Message edited by zac4mac on March 12, 2012) |
