I just reread your post. I have all be gaskets EXCEPT manifold..... Hmmm I hope your right��
Engine knock on 700 vmax
- Thread starter boutin73
- Start date
I just reread your post. I have all be gaskets EXCEPT manifold..... Hmmm I hope your right��
s10mike
Member
What's MrSled think? I'm no expert. Just stating with the easy stuff here. It does sound bad, very loud
s10mike
Member
Or MurderYamaha....whatcha think?
Vincent
New member
Oh man! It does sound like a bad lifter!
Vincent
New member
You'll need to pull the head and all 3 cylinders and see what you ve got.
Almost sounds like a bad rod bearing, hard to tell though, i would pull the head as well.
I pulled the head. All looked good. I'll probably have to pull the jugs... Really didn't want to have to but I'm at a loss and I don't want it to get worse!
I would pull the head and jugs to be sure of rod bearings..
Stonebridge
New member
Have a similar sound on my buddys venture 600. When I move the primary back and forth by hand i can hear a little rattle coming from THE crank. It was stored for years by an old man before he bought it and only has 1890 kilometers on it. I fear a bearing on the crank has gained some rust on it from sitting. Will pop the mag side tomorrow and see if some screw on the recoil is loose transferring the sound before I take out the crank.
I wouldn't yet.
Once head, carbs, airbox, exhaust and exhaust manifold are out of the way, cylinders come off with 4 nuts per cylinder.
Not sure of your level of expertise, but this is easy to do.
Should rule out a horribly leaky exhaust manifold gasket first.
I see a lot of smoke around the motor there..gotta be leaking from somewhere.
Once head, carbs, airbox, exhaust and exhaust manifold are out of the way, cylinders come off with 4 nuts per cylinder.
Not sure of your level of expertise, but this is easy to do.
Should rule out a horribly leaky exhaust manifold gasket first.
I see a lot of smoke around the motor there..gotta be leaking from somewhere.
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s10mike
Member
If it's from the bottom end, it's gotta be the loudest rod bearing I've ever heard. It's sooo damn loud, I would bet on manifold gaskets
Yeah really don't want to pull it if I don't have to but I was thinking about the advantages of cleaning up the belly if it were out. I'm very mechanical so that's no issue. I have the repair manual as well but it doesn't get too specific on teardown. I plan to check the manifold for any leaks before I do anything. It doesn't sound like a leaky exhaust to me but I have had three people suggest it so I'm definitely going to check that next. The smoke you see was coolant I spilled on the manifold when I popped off the head. Thanks!
Yes it is loud! That's why I am so nervous. It runs great but it's my first sled in 20 years so I wasn't sure if that was normal or not. Unfortunately it's not
s10mike
Member
If you pull your engine, it's a good time to give your wire harness a good look over for rub through
Okay so... I checked the exhaust manifold, no leaks. I pulled the head and jugs. I don't know if this is THE problem or just A problem. Severe scoring on the right cylinder and piston skirt. This piston doesn't seem any looser than the rest but I'm not sure what the tolerances are yet. New rod, piston, pin and needle bearing??
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Vincent
New member
That doesn't look good....
So while I am waiting on parts to come in I have another question. There appears to be two head gaskets on each jug. I saw another post that mentioned a similar thing. The gasket set I purchased I am sure does not have two for each jug. I assumed somebody else had been in there before me and double stacked them but now it sounds like there may have been a reason. Anybody have any insight on that?
stock is 3 layer, somebody probably did the thin head gasket mod to it in the past, very common.
I run 1 layer in mine.
Need good fuel though.
I run 1 layer in mine.
Need good fuel though.
Yeah it was one of your old posts that I saw the discussion about multiple gaskets and poor fuel. I'll see what comes in the kit. What is the advantage to running less than the three if that's original?