timing a 400ex??

[stalefish_132]

ok i did the head gasket on my EX and put it all back together and timed it to what i thought was right and it would turn over and sort of fire but not run, so i retarded it one tooth on the cam sprocket after seeing that it was out a tooth wiht all the marks lined up so i did that and doubble checked everything and it did the same thing:mad:
with it at TDC lined up with the "T" mark and all the cam lobes facing down and the marks on the sprocket in line with the head and then i put the tensioner on and it goes out or somthing:confused: i'm not dumb i've done a heap of 2 strokes and this is my 3rd fourstroke, first EX job andi have a book and i read it thought about 3 times and still cant quite get it right:grr:
any help would be great!

sry for the long post and spelling errors:blah:

[DAVE14]

sounds like youre doin the right things but are you lining up the marks in the inspection hole at tdc on the side of engine you must be on the right stroke with that right & the stuff youre doin on top it should be dead on I had no problems the last time mine was apart& thats what I did

[Ralph]

its the timing. Make sure that when the tdc mark is aligned that all the cam lobes are loose. No tension on them

[AirGuitarMaster]

maybe your on the wrong stroke

[ww228king]

did you lose the decompression dowel and spring under the cam.....my bro's did that for two days untill it dawned on us that it had fell out

[ww228king]

does it sounds just like this? ...woooow woooow pow!.....woooow woooow pow!......look under the cam and it should be a dowel sticking out like at a 45 degree angle....if there is just a hole then you have lost something

[DAVE14]

I never considered the decompression assembly i dropped a stage 3 hotcam on top of mine so the decomp wasnt necessary

[stalefish_132]

i know i put the little de-comp pin in and i'm sure its still in there.
its realy pissing me off right now, like i've done everythnig the book says and made sure thge piston is at TDC and set the cam with all the lobes facing down with the cam gear marks lined up with the head and then install the cam tensioner and turn it over by hand and its out:confused: my dad has built lots on engines and i've done few myself but nothing as confusing as this:mad: :grr:

[DAVE14]

well it sounds like a bit of a pain but ( tdc )through the side inspection hole will have the marks line up to get tdc with the piston up otherwise you arent on the right stroke but the piston could still b e up but on the wrong stroke & if the stock cam & decomp valve is in there with everything lined up on top should fire right up

[94F450SD]

try this.line up all your timing marks.grab the chain and put the side without the tensioner on the cam gear and adjust it or however it is doneyou want the side ofthe chain that doesnt have the tensioner tight.the tensioner will tighten up the other side on its own.

to make it a little less confusing.i dont have my book here so i dont know what side of the chain the tensioner is on.

so looking at the engine and the tensioner is on the left side you want to get the timing marks lined up and put some pressure on the chain to make sure it is on the crank gear.now put some tension on the right side of the chain and put it on the cam gear.now do whatever the book says to adjust the chain tensioner.crank it over and check the marks.if you do it the opposite way from how i just described the timing marks will always be "off" cuz when the tensioner tightens the chain it takesthe slack out of the right side of the chain.

[ww228king]

decompression shouldnt be in.......if you put a cam in without the decompression part on the camshaft then you suppose to remove the pin and spring also....if not then all it is gonna do is fall down in your motor and get hung up in your timming chain..

[stalefish_132]

Originally posted by ww228king
did you lose the decompression dowel and spring under the cam.....my bro's did that for two days untill it dawned on us that it had fell out

ok you called it! i forgot to put the little spring under the dowel. thanks for the replys

[ww228king]

no problem bro.....give it hell...have fun