Car won't start after mods
Thread Starter
Navigator
Joined: Nov 2005
Posts: 9
Likes: 0
From: East Troy Wisconsin
Car won't start after mods
I've exhausted the search feature and cant find what I'm looking for so I turn to the experts in the crowd.
I just installed, new Heads, Cam, camgears, headers, cat-back and after all of this the car will not start. It turns over and pops on 7 of the cyl but not enough to keep it going. The #3 cyl exhaust manifold is still room temperature but it should at least run, or stumble or something. Anyway I have double and triple checked the usual, the rotor points between 1 and 8 on the dist. cap I'm at top dead center when I should be, like I said it even pops on most of the cylinders and the pipes are getting warm it just wont start. Any help would be greatly appriciated. Thanks
I just installed, new Heads, Cam, camgears, headers, cat-back and after all of this the car will not start. It turns over and pops on 7 of the cyl but not enough to keep it going. The #3 cyl exhaust manifold is still room temperature but it should at least run, or stumble or something. Anyway I have double and triple checked the usual, the rotor points between 1 and 8 on the dist. cap I'm at top dead center when I should be, like I said it even pops on most of the cylinders and the pipes are getting warm it just wont start. Any help would be greatly appriciated. Thanks
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
I agree with Pete... but even an undegreed cam would allow it to run, no matter how poorly.
Also, do you try to manipulate timing during startup?
do you have fuel? have you tested the spark?
Also, do you try to manipulate timing during startup?
do you have fuel? have you tested the spark?
Racer
Joined: May 2006
Posts: 286
Likes: 0
From: Alpine California
I've been doing this for twenty or more years, I've been careful as heck, and I've STILL gotten one or two in 180 out! Don't know how, don't know why, but it still happens once in a while when visually bringing a new motor up to top dead center! Try resetting top dead center (assuming you didn't already do this), watching for the #1 Intake valve to open then close so you know your on the compression stroke, then bring the motor around till the timing marks line up
(you didn't change the ballancer or timing cover, did you?), and re-stab the dist. This should get you where you want to be.
Le Mans Master
Joined: May 2005
Posts: 7,362
Likes: 2,281
From: Central Maryland
Originally Posted by Blownfuel1
I've been doing this for twenty or more years, I've been careful as heck, and I've STILL gotten one or two in 180 out! Don't know how, don't know why, but it still happens once in a while when visually bringing a new motor up to top dead center! Try resetting top dead center (assuming you didn't already do this), watching for the #1 Intake valve to open then close so you know your on the compression stroke, then bring the motor around till the timing marks line up
(you didn't change the ballancer or timing cover, did you?), and re-stab the dist. This should get you where you want to be.
Be well,
SJW
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Team Owner
Joined: May 2006
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From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
After you have checked out the TIMING as stated above and determine the timing is correct,
How about the adjustments to your rocker arm's?
What did you set them at when you put it back together?(If timing is correct, it almost sounds as if you have them to tight leaving a vavle or valves hanging open, not allowing it to fire and run)
I would check the adjustment just to be sure, most will set the rocker's at a 1/2 to 3/4 turn at TDC(with both valves closed) most do not go with a full turn. Perhaps someone will comment on this more!
Hope this helps, Let us know what you find out. So others can learn and benefit!
Thanks,Matt
How about the adjustments to your rocker arm's?
What did you set them at when you put it back together?(If timing is correct, it almost sounds as if you have them to tight leaving a vavle or valves hanging open, not allowing it to fire and run)
I would check the adjustment just to be sure, most will set the rocker's at a 1/2 to 3/4 turn at TDC(with both valves closed) most do not go with a full turn. Perhaps someone will comment on this more!
Hope this helps, Let us know what you find out. So others can learn and benefit!
Thanks,Matt
Thread Starter
Navigator
Joined: Nov 2005
Posts: 9
Likes: 0
From: East Troy Wisconsin
After you have checked out the TIMING as stated above and determine the timing is correct,
How about the adjustments to your rocker arm's?
What did you set them at when you put it back together?(If timing is correct, it almost sounds as if you have them to tight leaving a vavle or valves hanging open, not allowing it to fire and run)
I would check the adjustment just to be sure, most will set the rocker's at a 1/2 to 3/4 turn at TDC(with both valves closed) most do not go with a full turn. Perhaps someone will comment on this more!
Ok I made sure I only used 1/2 of a turn on the rockers, I read posts on this before and was sure the valves were closed when I did this.
I installed the cam with the dots because the degree kit I have, the wheel was too big to fit around the cross member.
I have spark I checked that, the one thing that is wierd is the fact that the #3 header does not get warm, while all the others do. they pop but just wont fire over. I also don't have the tube from the cat connected to the unit by the A/C, and I dont have the EGR pipe to the exhaust manifold connected yet.
How about the adjustments to your rocker arm's?
What did you set them at when you put it back together?(If timing is correct, it almost sounds as if you have them to tight leaving a vavle or valves hanging open, not allowing it to fire and run)
I would check the adjustment just to be sure, most will set the rocker's at a 1/2 to 3/4 turn at TDC(with both valves closed) most do not go with a full turn. Perhaps someone will comment on this more!
Ok I made sure I only used 1/2 of a turn on the rockers, I read posts on this before and was sure the valves were closed when I did this.
I installed the cam with the dots because the degree kit I have, the wheel was too big to fit around the cross member.
I have spark I checked that, the one thing that is wierd is the fact that the #3 header does not get warm, while all the others do. they pop but just wont fire over. I also don't have the tube from the cat connected to the unit by the A/C, and I dont have the EGR pipe to the exhaust manifold connected yet.
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
it sounds like a timing problem...if the valves are set close, but not to tight.And 
don't know how many times in the past 40 plus years I've got the dist. off. I'd start by verifying #1 at TDC,valves closed, then make sure the rotor is pointing to #1, BTW, being off could be the cause #3 isn't getting warm.