timing problems ka24de. had it running, upper chain skipping links? wtf

[seattlebmxs13]

hey guys, searched but couldnt really find anything about this.

onto my problem.

my 91 240 was leaking oil and i had turbo plans for it so i figured i would tear it down and do new gaskets and seals, piston rings, head studs, and i threw in some brian crower v2 cams in. Im pretty confident i have the cams installed correctly ( swapped intake and exhaust and such)

my problem is this. my upper timing chain appears to be skipping links? but when it does my cams stay where they should the chains just not lined up where it was.

i had the engine running nice and strong one time, this was just after i had replaced the upper timing chain tensioner.

fired right up, throttle was responsive, everything was great. f***in awesome except i was getting the timing rattle. i figured it would be good to just get a new chain, i removed the upper guides as well.

so i turn it off and it wont fire up again! wtf. i pull off the valve cover and the chain looks like its skipped a couple links, i credit this to a loose chain and go get another one.

so i get one, put it in and fire it up the next day. i can already tell its not running quite right, the idle sounds weak and when i gave it gas it would just bog the engine like it wanted to die.

so i pulled off the cover and sure enough, yup the chain jumped a good 4 or 5 links. the cams were still in the right place though!

so i figured since the tensioner was mainly oil pressure run i would hold it under oil and prime it by pumping the air out. didnt work.

so now i have no idea what to do, i did notice that when i turned the crank over twice by hand the cams turned once each which seems normal to me but the timing links would not be in the same place each time. is this normal? am i just retarded? i'm really clueless for what to do next.

someone please help me!

[Valiant240sx]

im having the same problem i just installed all new seals, tensioner, guide and chain, got everything right where it was supposed to be and pow it jumped time by 3 links, so got another new chain and it does it again >.<.

ill let ya know if i find anything out.

[seattlebmxs13]

well kinda good to know i'm not alone.

sucks doesnt it?

seems like somone would know something...
Modified by seattlebmxs13 at 2:38 PM 9/16/2009

[youngun21a]

Are you guys talking about the chain marks..cause those don't line up always..and also don't think there is enough room for the chain to jump and if the cams stay the same...unless i'm wrong...and if it did jump think u would have more trouble than just not starting....could just be the dizzy not bolt right or of a tooth...

[seattlebmxs13]

im pretty sure its not the distributor, ive spent plenty of time messing with that. its got a new cap and rotor too. that wouldnt explain why it runs sometimes on the initial startup anyways.

someone out there please help! i really dont want to take this to a shop.

[seattlebmxs13]

bump. need help

[2ndnissan]

Try removing the oil pump and moving that shaft a tooth or two . I changed my chain on a sohc and it ran but no real power. I had tried to adjust the distributor first and it just would not turn far enough to make a difference. After moving the drive gear and changing the position ,it worked fine. Just a thought. ...

[seattlebmxs13]

hmm thats a single cam tho. i dont know, i think i;m gonna have to take the entire front cover off to f*** with all the timing bulls***. awesome.

anyone else know anything?

[seattlebmxs13]

hmm guess ill check some other forums then...

[fender-startocaster]

I'm having the same problem. I know the timing marks only line up evry few turns. Crank it by hand a few times and you will see. Still can't get the car to turn on

[royalscew]

I'm also having a similar problem with upper timing chain on 1997 Nissan Altima (KA24DE). Put car together after head overhaul, new tensioners, resealed lower timing cover, etc. Car started fine and ran great for about 2 minutes then died with horrible racket. Checked upper timing chain and it jumped one tooth on both camshaft gears. Both tensioners are brand new. Perhaps tensioner was oil starved and retracted in bore? Can't figure out what to do, just hoping that valves weren't bent and will try again with another new tensioner. If I push the top tensioner back in its bore, I notice that sometimes it gets stuck that way. I think it may be a bad tensioner (damn you, Autozone..)

Anyone have any other ideas? Anyone know if this engine will bend the valves if the chain is off one tooth? I know it is an interference engine, but how far off does the chain have to be for the valves to hit? I will try to re-time it and run a compression check. With the current off-one-tooth timing, I get the following cold engine compression numbers:

#1 - 130 PSI#2 - 125 PSI#3 - 90 PSI#4- 115 PSI

Not sure if this indicates that #3 hit the valves or not, but I am suspecting that may be the case since all the numbers should be the same for an inline 4 no matter how far off the timing is, no?

[OutToWinPAHC]

Did you guys replace these tired old chains? Did you also use the FSM for setting clearences and checking side slack.

And stop bumping, this is not online help for comcast, someone eill eventually chime in and help if they can.

[OutToWinPAHC]

hmm guess ill check some other forums then...

BTW you postd in 240 general discussion, not technical, or engine specific technical. Moving to KA.

[royalscew]

Look, go piss up a tree. No one has answered the previous questions in over a month, so I thought it was valid to bring this up again. I have a serious issue with a Nissan Altima, and this just happens to be, a Nissan FORUM!! I am so completely off base by posting here! I must be an idiot or something..

Did not replace the chains since was told that they last a long time. Car has 120k miles on it so double roller chain should be fine with this many miles. Valve clearance and cam endplay are NOT the problem! I took pictures of the timing gears and chain before starting the car and compared current timing to the pictures. The chain definitely skipped a tooth on both cam gears, it is plainly clear from the pictures. The only cause is the tensioner failing, since car was originally timed correctly.

[Razi]

The timing chain "dots" don't line up all the time.When I put my chain on, aligned them and everything, and manually rotated my crank, the dots did not line up the 2nd or 3rd or 4th, etc... time around.

[OutToWinPAHC]

Nice reply, let see if I cant make it your last post here.