car won't start after replacing upper chain tensioner

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skwertle
Posts: 162
Joined: Wed Jul 24, 2002 4:31 am

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Ok i replaced my upper chain tensioner and now for some reason my car will not start.

the motor turns, i get gas and spark, but the engine will not start.

when i initially took of the tensioner and put in a new one. i forgot to turn the crankbolt to TDC on piston one, nor did i line up the distributor correctly. And tried to start the engine. It didn't start cuz timing was really off.

so I took off the distributor and set the engine to TDC on piston one, put the distributor in the correct way and it still won't start.

So, now i took off the front cover (just the upper part) to get a good look at my upper chain to see if it skip teeth but the markings on the chain are gone. i see 2 darker links and one brighter link on the chain. are thoughs the marks? if so they are still in the correct spot.

the only thing i can see out of place is that at TDC the camshaft marking on one of the cams isn't orientated the exact same direction as the picture in the FSM. but if the chain is aligned correctly how can it be off?

does anybody have any idea what's goin on? does anybody know the number of links between the 2 camshaft markings and idler sprocket?

help


skwertle
Posts: 162
Joined: Wed Jul 24, 2002 4:31 am

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also forgot to mention that in order to get the timing right i had to put i the distributor a little bit offset from where the FSM says to align it.

so what does that mean?

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rudeboy
Posts: 139
Joined: Tue Sep 10, 2002 2:21 pm
Car: cars

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that means your cam timing is off...you need to pull off the front cover and re-alighn your crank and cam timing...then set the dist....pain in the as but do it right this time so you dont have to do it again...there is another trick. but it's a cheat. i'll just advise you to get it all correct.actually...now that i think of it..you can get you bottom end to TDC, the if you had to re-arrange you cams to get em correct.it could(key word-could) save you time.but since you did all that and have no compression...i say give it a good run through, replace your crank seal and enjoy...i hate that job

skwertle
Posts: 162
Joined: Wed Jul 24, 2002 4:31 am

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great i will do that but the markings on my chain are gone.

Anybody here know the number of links?

yellow_jacket
Posts: 1355
Joined: Mon Jan 13, 2003 4:43 pm
Car: 95 240sx

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did you try rotating the distributor 180 degrees?

Get your cam timing correct first of course.

skwertle
Posts: 162
Joined: Wed Jul 24, 2002 4:31 am

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yellow_jacket wrote:did you try rotating the distributor 180 degrees?

Get your cam timing correct first of course.


Actually that way way too much. but to answer your question yes. I had to rotate it about 2 teeth, say 30 degrees, to the right for the timing to match up. (checked with timing light.) but still doesn't run.

skwertle
Posts: 162
Joined: Wed Jul 24, 2002 4:31 am

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Ok. so i'm gonna take the whole front end and all the chains off but since i really can't see all the markings does anybody know how to align them without markings (number of links)?

Like i said before i can see the bright silver marking but none of the others.

alex7542
Posts: 120
Joined: Thu Nov 20, 2003 11:00 am
Car: Racing and high horsepower

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Hey skwetleI jsut finish doing the timing in my 240. You shouldnt have to take the bottom chain off. And between the two camshafts there is 6 links not including the marking links.And between the timing mark on the bottom chain with the intake cam is 9 links. i have a ka24de from a 92 i dont know if the marks are different because of the cams.

And when u had the timign completly bad make sure u did not bend any valves when u tried to start it. it happend to me

and this is how you set in on my motor.The timing mark on the crank is on the bottom a little to the left the intake came is up (the little timing mark) its like straight up. and the exhaust came is to the right at about 45 degress. Make sure u put pistion number one on tdc. and the intake and exaust in compression.

if you have any questions jsut ask

skwertle
Posts: 162
Joined: Wed Jul 24, 2002 4:31 am

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alex7542 wrote:And between the two camshafts there is 6 links not including the marking links.And between the timing mark on the bottom chain with the intake cam is 9 links.


Dude that was exactly the info i needed thanks alot. But goin by what u said everything is correct so i prolly did bend a valve. guess i'm goin to have to have a look and see.

Thanks for the help everybody.

alex7542
Posts: 120
Joined: Thu Nov 20, 2003 11:00 am
Car: Racing and high horsepower

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NO PROBLEM

yellow_jacket
Posts: 1355
Joined: Mon Jan 13, 2003 4:43 pm
Car: 95 240sx

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If you have the distributor 180 degrees off the timing light will fire on the correct mark on the crank, but it will be firing on the wrong stroke still. Or, if you don't feel like pulling the distributor to do it, change plug wires 1 &4 and 2&3.

alex7542
Posts: 120
Joined: Thu Nov 20, 2003 11:00 am
Car: Racing and high horsepower

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hey Yellow JacketYour right about the thing of switching the wires. but when ur doing timing do it right. dont do it a fixed way. best thing is for you to take it off again and put it in the right sequence not changing the wires.

yellow_jacket
Posts: 1355
Joined: Mon Jan 13, 2003 4:43 pm
Car: 95 240sx

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I would have to agree with you on that. I just couldn't think of how to explain it to him so he would understand. I had tried to get him to do it earlier but he didn't grasp what I meant.

neekap
Posts: 33
Joined: Tue Jan 06, 2004 4:00 pm

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actually, ive run into a similar problem with my cam timing. what is the best way to get the upper timing chain off, and also, how do you check if a valve has been bent?

yellow_jacket
Posts: 1355
Joined: Mon Jan 13, 2003 4:43 pm
Car: 95 240sx

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For a 91 you can take the front cover off and take the upper chain off pretty easily. A bent valve will show up as low compression on a compression check

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rudeboy
Posts: 139
Joined: Tue Sep 10, 2002 2:21 pm
Car: cars

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yep. once is all said and done and you are sure all the componets are timed, the do a compression check.nice to know type thing.

even on a cold motor. if it dosent start and you atleast have 150+psi th3en you know the problem is in another area....

i mixed up fuel lines on a motor swap and spent an hour checking everthing else...but once i knew i had compression, it seriously narrowed the hunt


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