Ok, this is performance related thats why its here
I want to know what would cause my car to jump timing?
Story, I havent been running no more than 10lbs of boost lately.. I drive the car last Friday for only 20 mins bring it home, parked it.. Go to start the car up at midnight and I hear this grinding\rubbing noise.. Im like dammmit.. Try again and still does the same thing..
Anyway, long story short Im in the process right now, take off my timing cover and see my damn chain has SLACK in it.. All the shoes are in, BUT the plunger that pushes on the lower shoe is halway inside of its housing(btw, I have 2.4) How in the heck did the plunger disengage itsself? I first thought the noise was a lifter, or valve spring until I saw this.. So im out in the garage right now about to pop my plunger back up so it makes contact with that shoe again to see if it tightens up and Ill turn the engine by hand to see if it makes that grinding noise again.. Im 99% sure this is my problem..
Is the 2.4 timing THAT weak that it cant handle boost like that? I know alot of us are boosted, but damn..
Thanks for any input on preventing this from happening again.. I think im going to buy a new timing set so I can get a new plunger.
Sorry for the rant.
~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD
AUTOMATIC!!
328 HP
306 TQ
isn't timing chain slack a common thing in 2.4s?
My car may run 18s, but I can do your taxes in 10 seconds flat.
JBO lube - they would never have enough in stock and we'd never see RodimusPrime again
only time ive had that happen was when i reused the tensioner, which design do you have, the 2 piece one where the shoe and tensioner is seprate, or the on where the shoe and tensioner is all one piece?, ive been told the 2 piece is the better design... but i would say buy you a new tensioner, also did you disengage the piston in the tensioner when you built your motor?
R.I.P. Brian Klocke, you will never be forgotten
Fixed it!! I engaged the plunger again and I then turned the crank by and and no more noise
Wheww I thought I was going to have to take my cams and all that apart.. So, tomorrow im going to get a new plunger and replace this one I have on the car now.
Brandon, I have the kind where the shoe and tensioner is seperate.
Also since we installed the motor in my car I have had my timing stuff on and off about 5 times now.. And yes I remember the last time we did this we fully engaged the plunger(trd cavfire) helped me time it and it ran fine until boost lol..
I guess its faulty now since its been taken off so many times for various reasons.
Thanks for your guy's input.
~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD
AUTOMATIC!!
328 HP
306 TQ
I think you need to pull the head off. yes the tensioner is your problem, but you could have bent a valve while trying to start the car. Well first did you check to see where the timing marks are? Is everything in the correct spot? If so then you are probably ok, if not you could have problems.
FU Tuning
John no the car is not timed anymore,and it wasnt timed when I first took the timing cover off because the teeth jumped the chain.. So, you think i need to check the valves huh? Could I pull my manifold off and look into the intake ports and see that way? Or do I need to check the bottom of the valves?
~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD AUTOMATIC!!
328 HP
306 TQ
You can see if they all close by looking in the ports. Sucks to hear about that happening. I've seen the same issue, but its usually with the 1 piece tensioner design (my '95 had that happen, as well as Chris's GTZ)
Keep us updated on what you find!
SPD RCR Z -
'02 Z24 420whp
SLO GOAT -
'04 GTO 305whp
W41 BOI -
'78 Buick Opel Isuzu W41 Swap
Yup, gotta bent valve ladies and Gents!! Sucks to see that when I pulled my intake mani off.. I guess it happend when I tried to start the car after it jumped timing
Ill keep this updated when I pull the head with pics and stuff..
~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD
AUTOMATIC!!
328 HP
306 TQ
Btw, can COMETIC Headgaskets be re-used? They better be lol
~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD AUTOMATIC!!
328 HP
306 TQ
yes they can..
Built&Boosted moar
04 Cavalier Turbo r.i.p my baby
2nd place 2009 GM tuner bash qwick 8--holla
sucks man....i'm free next weekend if you need help tearin it down or reassembling..whatever point you're sitting at...i'd like to make sure everything is set this time around, i need this car following me to the bbq!!!
Sweet..
Paul thanks for comming down and helpin out the other day.. Ill definately let ya know what point im at by this weekend..
~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD AUTOMATIC!!
328 HP
306 TQ
SweetnessGT wrote:Wow man that's a shoddy spell of luck right there.
Get 'er all fixed and put back together! I hope you didn't knick the piston too hard...
-Chris-
thats what I'm worried about, i'd hate to see his nice new pistons nicked
Call me up homie and I'll be over helpin out!!
2000 Camaro V6.
| SLP Loudmouth | CAI Intake | HID's |
Mat ive been tearin it apart all week, each day I do a bit at a time because I dont wanna get stressed out and throw a cam at the garage wall or anything
.. By Friday I should have the head off to see how many valves I need to order
~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD
AUTOMATIC!!
328 HP
306 TQ
And hopefully no pistons.....
Wrench Monkey wrote:And hopefully no pistons.....
Exactly..
Btw, what should I be looking for on the pistons to see if their too damaged to re-use?
~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD
AUTOMATIC!!
328 HP
306 TQ
good luck man! sorry to hear about that but she will be up and running in no time!
WHITECAVY wrote:Wrench Monkey wrote:And hopefully no pistons.....
Exactly..
Btw, what should I be looking for on the pistons to see if their too damaged to re-use?
Any indents from the valves, knicks anything like that.
If the piston is scratched you *could* polish it out. But i would play it safe with the pistons. Any sharp edges or knicks willl make it that much easier for your car to detonate under boost. What happens is a hotspot is created on any uneven surfaces making it possible to detonate.
^^Thanks Wrench, wish me luck.. We shall see..
~2014 New Z under the knife, same heart different body~
______________________
WHITECAVY no more
2012 numbers - 4SPD
AUTOMATIC!!
328 HP
306 TQ
small dents will be fine, but like Monkey said, polish them the best you can. If they are out towards the edge of the piston, make sure your rings spin freely yet.
SPD RCR Z -
'02 Z24 420whp
SLO GOAT -
'04 GTO 305whp
W41 BOI -
'78 Buick Opel Isuzu W41 Swap