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TheDonNonn
Dodge Dakota
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6/23/2003
00:59:22
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 Subject: just my luck....
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Well I finally got around to putting in my HO cams this weekend. Installation went alright, no big surprises(thanks to all the posts on here).
But get this..when I started the truck afterward it ran real rough, but I thought it was just getting used to the new cams. It did smooth out a bit, so we let it sit a while idling and then we took it for a ride to break them in. After stopping off and getting food a check engine light came on. I checked the code, and it said cylinder one misfire.
Now, I know we installed everything right, sprokets lined up and all. Driving down the road its fine, however idling in drive its real shaky and sounds and feels like it wants to stall. So anyway we check the coil and injector and plug on cylnder one, all was fine. Randomly we thought to check compression, to make sure the valve was closing right. Aparently its not, because its only putting out about 50 psi, compared to the others that are 150 psi...
So what the hell is goin on here?? If the cam was off it would run bad all the time right? And all the cylnders in that bank would misfire wouldnt they?? Could the cam be bad??
Any thoughts?
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Chris
Dodge Dakota
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6/23/2003
08:21:10
|  RE: just my luck....
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Sounds like when you put the cam in you knocked one of the rockers off it's pedestal, I did this on my install last summer (one of the first to do it) and luckily I noticed it before i installed it... time to pull the cover and check this out.
Chris
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ScottE
Dodge Dakota
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6/23/2003
08:51:04
| RE: just my luck....
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Ditto - my money would be on a misplaced rocker. I did this on my cam install, got the same symptoms, and before I got the engine shut down, the offending rocker was poking out through my valve cover! New rocker, about $30. New magnesium valve cover - $150. Pull the cover and check the rockers!
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TheDonNonn
Dodge Dakota
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6/23/2003
09:00:08
| RE: just my luck....
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One more thing...on the way to work this morning I could defenetly hear a "tick tick tick". The rocker being off was my guess too...thats probably what it is.
Thanks guys
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TheDonNonn
Dodge Dakota
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6/24/2003
18:52:33
| RE: just my luck....
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Bad news...i pulled the cam and the rockers are all fine...they were sitting in place like they should be. I dont know what to do now. The cylinder has little compression but the springs seem to be functioning the way they should be.
Whats the chance of the cam actually being bad?
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ScottE
Dodge Dakota
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6/24/2003
20:30:38
| RE: just my luck....
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Some things to check out:
1 - Did you check the lifters as well as the rocker arms? Unlikely, but a piece of trash may be binding one up.
2 - Cam sensor - you don't say what year your truck is, but I do remember seeing a TSB regarding a washer/spacer being needed to stop the sensor tip from striking the cam "wheel".
3 - Cracked plastic plug "boot", or a damaged wire, allowing a short to ground on the offending cylinder - this would align with the misfire code.
These are all that come to mind for me. And of course, yes, the cam could be bad - could pull it again (practice practice practice) and have a machine shop check it out. But I'd check the other items first. Good luck!
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TheDonNonn
Dodge Dakota
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6/24/2003
23:41:28
| RE: just my luck....
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Scott...I checked all that. The plug wires are alright, as are the injector wires. Its a 2000..I'm not sure about the cam position sensor TSB..but i dont think that would have to do with not having much compression in cyln. #1.
We put it back together the second time after taking it out and checking everything over again...it started up a little rough but seemed to smooth out with driving, and the ticking was still there, but it ran much better than the first time. It actually seemed to run on all 8 cylinders..Then the check light came on once again, and it began to run like crap once again.
The only things we can seem to notice being wrong are the fact of not much compression in the cylinder and that ticking. Almost sounds like valve noise????? How can that be??
No one else has had this touble with HO cams?
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dcxer
Dodge Dakota
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6/25/2003
00:40:55
|  RE: just my luck....
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Hi,did you check the cam timing (C/L)with a degree wheel at installation? What side of the engine has low cranking comp? Tip! Always install the rockers after the cam is installed. Check the rt side cam timing.
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TECH
Dodge Dakota
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6/25/2003
01:23:06
| RE: just my luck....
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I'm not familiar with this engine, although I have one myself, but it's possible that you bolted down the cam, when the crank was not in the correct place, or the cam for that matter. Is it possible that you forced a valve down onto a piston during install? Like I said, I'm not familiar with this engine, so I can't be of much help. I'll probably do the cams in mine at a later date though.
Do a cylinder leakdown test to find the cause of low compression. If you hear a leak at the intake, it's an intake valve, the tailpipe would be an exhaust valve, and the oil fill cap would be piston/head problem.
I don't see the cam being bad unless a lobe just wasn't there-unlikely that it would be warped/bent, but you never know.
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TheDonNonn
Dodge Dakota
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6/25/2003
07:39:09
| RE: just my luck....
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Its the left side that has the problem, in cylinder 1. I think the cam timing degree is right on, and if it wasnt the other cylinders on that side would be effected too (?)
TECH-The ticking comes REAL loudly through the exhaust, I suppose it doesnt help that I have a slight exhaust leak, but all it does is make the tick even louder. I couldn't have pushed the valves open (in cylinder 1, anyway) because the engine was set at TDC.
So if that ticking is coming from the exhaust valve, how could that have happened?
Would it be bad to swap out the HO cam and put the stock one back in only on that side to see if the ticking goes away and if my compression comes back? Or would that mess up the computer?
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TECH
Dodge Dakota
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6/25/2003
08:07:34
| RE: just my luck....
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If you change out only one cam, it'll run, but it'll probably run worse, but the ticking might go away, IF it is in fact a cam problem.
The best way to know for SURE if you have a valve messed up is to do a leakdown test. That puts the affected cylinder on TDC compression, fills the chamber with compressed air via the spark plug hole, and measures the amount of leakage leaving the cylinder. As I described in my first post, is the way you located where the air is leaving the combustion chamber. It should be below 20% leakage, probably a lot less actually. Compare the readings to other cylinders to get a baseline.
Good Luck.
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dcxer
Dodge Dakota
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6/25/2003
12:49:19
| RE: just my luck....
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I agree a leak down is in order.Once again you need to check the cam centerline with a degree wheel.Do not trust your eyeballs.You didn't mention a vacuum reading at idle.What does it have? Easy to bend a valve if the engine was turned over when it was out of time.Also you might want to check the valve springs.They break without notice at times.Hope this helps...
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TheDonNonn
Dodge Dakota
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6/25/2003
23:08:06
| RE: just my luck....
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The valve springs looked to be alright...I really doubt the engine was out of time the first time I started it, nothing moved during installation. The only way it could've been out of time is with a bad cam.
I dont know what the vacuum is at idle, and I may try the leak down test. Either way I'm diving back in tommorrow.
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TheDonNonn
Dodge Dakota
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6/30/2003
12:42:35
| RE: just my luck....
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If anyone is interested here is an update:
I swaped out the cams back for the stock ones, and it runs like it always used now. Except that the ticking is still slightly there, and checking the compression cylinder #1 has 120 psi now, before (with the HO cam) it only had 90. But it runs and drives down the road just like it used to...
I dont really know what to do right now but I emailed the company I bought them from and told them my story. I know its bad to assume but it seems like that cam is not right, and it did some damage to my truck because it never used to tick, and I'm sure it had the correct amount of compression before the install...
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gps_jetskier
Dodge Dakota
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6/30/2003
12:53:19
| RE: just my luck....
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Keep me informed. Curious to see how you make out. Like I said. Mine ran rough at first, but after resetting it seems to be fine....so far....8-). Wish I could help ya. I don't have alot of experience with this motor, but the swap seemed to go pretty well.
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RobertG
Dodge Dakota
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6/30/2003
12:53:46
| RE: just my luck....
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Check the valve lash adjusters & valvesprings. The leakdown test will tell you if its intake, exhaust valve, or rings.
I'm not trying to be mean, but most of the time when a cam swap goes bad, its the fault of the mechanic or parts selection, not the parts themselves. Keep us posted!
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TheDonNonn
Dodge Dakota
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6/30/2003
14:15:16
| RE: just my luck....
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Robert I totally understand what you are saying, which is why I double checked everything a few times. Human error is far greater than machine error(as in when they made the part).
But I just sent it back to them to check it out, I'll let you know what happens.
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