350x engine rebuild questions

[Jonpin]

Im going to be rebuilding 2 350x engines ,is there any thing i should realy know befor i start doing this ,one im just doing a top end on the other im changing out the center cases on "thats the one im kinda scared of" i did a top end rebuild on my 200e wasnt bad at all but i want to make sure its right the first time .any pistons i should look to buy i was looking at the wiesco ones on ebay ,i still dont know what the bore size is yet so i cant buy the pistons yet ,how do i know if the timeing chain should be replaced ,any way to know if the valves are seated good ,ill be changing the valve seals as well "any tips on how to do that" i do have the manuel to" how do i know if the oil pump is worth a poop . sorry theres alot of questions but im very scared of messing something up .

[SWIGIN]

as far as the oil pump, they are over looked most of the time.

open it up and see if its tore up on the inside. 3 little screws is all it takes to open one up.

as far as the motor, its no different then any other motor. lap the valves and check with liquid or a even a flash light to see if they seal.

[Texas 200x]

If your spending the money time and effort to rebuild the motor, just put in a new oil pump. That way you won't have to worry about it. The oil pump is one of the MOST important things in your engine. As SWIGIN said you can look at the inside. Any kind of roughness or grooves is wear. You lose a little pressure out of the those grooves and eventually it will drop to low.

[Blown 331]

So oil pumps are known 350X problems? I'm not even sure where it is located and can I check it without pulling the engine apart? Like if I want to check mine right now with the bike completely together.

[SWIGIN]

all old 4 strokes need the pumps looked at IMO.

its under the clutch cover

[Dirtcrasher]

Yes yes yes!! I got a brandy new one for 45$....

Gotta get the fresh oil up there!!

I think the 350X pump is discontinued now though?? But I thought there was one you could modify to work like the 300EX or something??

[WIkid500]

Dirtcrasher where did you get your pump from? I want to get a new one or rebuild the one in my 200x when I do my engine work.