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Corkster
Dodge Dakota
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2/05/2004
21:18:43
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 Subject: 4.7 Bent Valve
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Hello all,
I have a 2000 Dakota SLT 4x4 Club cab with a 4.7. About a year ago I ordered the H.O. cams and had a friend of mine who runs a garage install them for me (I paid him to do it). Well, when he was test driving it after the install, the cam on the passengers side failed. The pin that fits into timing chain sprocket had snapped off and caused the cam to slip and throw the timing way off. Needless to say, the truck quit and wouldn't start. After they figured out what happened, they ordered a new cam, put it in and everything ran fine until a couple of weeks ago. Driving to work one day a couple of weeks ago, I heard a loud clunk from the engine compartment and it started running really crappy and vibrating really bad when I gave it gas. I took it in the shop, and the error code it was throwing said no fire (Bad miss) in cylinder 2. Once they took the valve cover (Camshaft cover actually) off, they noticed that the valve in cylinder 2 was bent and rocker arm was just laying there next to the valve. It just happens that the bent valve was on the same side that the bad camshaft was on. I was wondering if anyone else has run into anything like this, or if anyone has ever had a valve / rocker arm problem with a 4.7 engine ?? I tend to think it all goes back to the camshaft problem last year.
Thanks for any insight you might have !!!
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R/TBlues
Dodge Dakota
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2/05/2004
21:46:42
|  RE: 4.7 Bent Valve
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It maybe related. How many miles have you put on the engine since the cam swap? It sounds like the valve seized in the guide. The rocker arms usually bend/break before the valve stem. This really sounds bizzar. That's the one thing that's nice about a push rod engine. If something goes bad in the valve train the push rods will usually bend. When you dissasemble the engine, check the valve spring. It sounds like the valve floated and hit the piston and that bent the stem. The bent stem would have siezed in the valve guide and that would cause the rocker to break. It sounds like this maybe something for everyone that has done the HO cam swap to look into. Maybe the HO cam uses stiffer springs? Has anyone checked to see if the Jeep HO engine uses the same valve springs as the Dodge engine?
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Kowalski
Dodge Dakota
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2/07/2004
10:16:30
|  RE: 4.7 Bent Valve
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The HO cams will work fine with the stock valve springs; only hotter cams than that need different springs. Both of your problems were likely due to improper installation. I'll bet the valve was bent by being forced during the installation, then eventually failed. Cylinder 2 is on the passenger side, and I noticed while doing mine that the cam would fit in place in an improper orientation on that side, but bind when you go to rotate it into position to tighten. He probably forced it, then figured it out and re-oriented correctly. Pin failure will occur if not using the factory tool, or a workable alternative - some have held things tight putting a wrench on the crank bolt instead. I have a plow frame in the way and held the cams securely with a large pair of waterpump pliers while a friend torqued the cam gear bolt. If you stress the pins at this stage, they fail like yours did. Your mechanic did a lousy job. Another tip for anyone doing this mod - zip tie the chains to the gears.
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R/TBlues
Dodge Dakota
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2/07/2004
10:55:25
| RE: 4.7 Bent Valve
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Kowalski,
I agree with your diagnosis. But, the guy talked like this cam swap was over a year ago. That's why I asked how many miles was on the engine. Since the guy never answered my question about the mileage we don't know if it has 30,000 miles since the cam swap or 300. The fewer miles it has on the cam swap the more likey your correct. If it has 30,000 or more miles on it, I would tend to think something else went wrong. Even then, it is probably a istallation issue. A bent valve would seize very soon. The longer a bent runs without seizing the less likely it will ever seize.
He did say he heard a large clunk under the hood while he was driving. That would suggest that the valve slapped the piston.
CORKSTER!
This is your thread. How many miles have you put on the engine since the cam swap?
Kowalski
I think half these threads are bogus. This guy probably doesn't even own a 4.7L Dodge. Just someone else coming on here trying to stir something up. Wouldn't you be checking your thread if you had his problem?
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Corkster
Dodge Dakota
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2/07/2004
13:20:00
| RE: 4.7 Bent Valve
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Sorry for the slow reply back. And thanks for the responses. I've put about 11k miles on the truck since the cam swap. One thing I did notice was since that time was a light pinging sound coming from that side of the truck. Never really thought much of it since the truck ran fine and didn't have any other symptons. I also agree with you that the first cam failure was due to improper installation. I also purchased the tool to keep the cam chain tight an in position and they used that during the install. I even printed off the Mopar installation instructions for installing the cams and gave to them to make sure they did it right, but to no avail. The same shop is fixing the valve. I think I have them convinced it was their fault to begin with, but just wanted some other opinions. I appriciate the feedback !!!
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R/TBlues
Dodge Dakota
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2/07/2004
14:37:58
| RE: 4.7 Bent Valve
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Wow!! A shop that admits being at fault?? Some shop owner out there actually has some integrity? BLOW ME AWAY!
That's cool. I'm sorry for the last negative post I made. I was getting very frustrated by you not coming back and answering your replies. I was beginning to think that maybe you were actually a Chevy owner trying to get us Dodge "Nuts" going at each other. Some of us are a little high strung.
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Corkster
Dodge Dakota
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2/07/2004
18:52:01
| RE: 4.7 Bent Valve
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Even though they admit they more than likely caused the problem, I'm not getting away totally free. They are going to eat the labor costs, but I still have to pickup the costs for parts (New vavle, rocker are, machine shop costs). Still I'm not expecting a really big bill !!! I was wondering if any other 4.7 owners out there have had any internal problems with their 4.7 engines along the lines of mine, and if anyone else has had any problems with the H.O. cams. Thanks !!!
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xplikt
GenIII
2/08/2004
00:39:32
| RE: 4.7 Bent Valve
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The valves, rockers, and coils are pretty cheap if I remember right...well, when you need to buy one set anyway.
-Mike
http://www.dodgetruckworld.com/xplikt/
2002 2WD RC SLT 4.7L 5spd 4.56 LSD
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Kowalski
Dodge Dakota
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2/08/2004
09:47:09
| RE: 4.7 Bent Valve
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All of the problems I've heard about seem to have to do with improper installation. A search of the archives will show just about any way possible to screw this up. I would suggest to anyone doing this, that is a worthwhile read; and you should have no problems once you know what to watch out for.
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Corkster
Dodge Dakota
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2/13/2004
19:42:58
|  RE: 4.7 Bent Valve
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Well, thought I would update everyone. Got my truck back yesterday. So far so good. The engine is much quieter than it has been since before the install of the H.O. Cams. After driving it for a couple of days now, I actually think that rocker arm / vavle on cyl #2 might not have been 100% right for quite a while. Maybe it's just me, but it seems much quieter and much more responsive than it had been, like maybe the valve wasn't quite seating (or not opening or closing all the way) all along. I'll give an update again after I drive it for a week and the computer gets itself readjusted again.
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The Don
Dodge Dakota
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2/14/2004
16:17:09
| RE: 4.7 Bent Valve
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Over the summer I tried to install HO cams on my 4.7. I say tried because without me knowing the engine rotated just a little bit(who needs a spanner wrench anyway???) To make a long story short I bent a couple valves. I didnt know that however and I just blamed the cams for the crappy running and engine codes. Well$3000 later I have new stock heads and still no HO cams : (
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TexasTodd
Dodge Dakota
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2/14/2004
16:32:11
| RE: 4.7 Bent Valve
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Don, and others,
Shade tree mechanics advice. If you make sure all the marks line up after your done, before the valve covers go back on, it saves alot of headaches. I usually rotate the engine to see if it binds, before I crank it.
With that being said, my friend and I did mine and his truck on the same day. Even after looking real good, on the second install, one of his rockers had come off. Ran bad but no real damage. We put everything back together, he took it to the shop under warranty, told them he just started it, and it ran bad, which wasn't a lie, and they fixed it for free, under DC's warranty.
So, even being careful, we weren't immune. My truck was first and no probs, his second, and like I mentioned. Good thing it was nothing major.
We used a homemade wedge (some don't use any), and I think I remember zip tying the sprocket to the chain, on each side.
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The Don
Dodge Dakota
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2/14/2004
21:22:37
| RE: 4.7 Bent Valve
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Todd..I thought that I had check the marks on the sprockets to make sure they were aligned, I could have sworn they were. I guess I was wrong..
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TexasTodd
Dodge Dakota
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2/14/2004
21:55:03
| RE: 4.7 Bent Valve
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Don,
If you still have the cams, it might be worth trying again, having someone help is nice for two minds going at it. the gains are worth it, if you still have the cams, it cost next to nothing to install them. Same gaskets, etc.
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Corkster
Dodge Dakota
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2/14/2004
21:55:53
| RE: 4.7 Bent Valve
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All... Thanks for all the responses. I'm glad to hear I'm not the only one to have a rocker arm / valve problem after installing the cams. On my install they even used the wedge tool, but still a rocker arm wasn't seated right and the valve ended up bent once the rocker arm fell off. I guess I should be thankful since no internal damage to the engine. I did get to see the engine with the head off which was kind of cool. The mechanic (a good friend of mine)was really impressed with how easy the engine was to work on. He said he didn't have to force anything putting it back together. It just all went back together nice and easy. Also, I use Mobil 1 oil and he commented how clean everything was inside the engine. Good luck to everyone out there installing the H.O. cams !!!
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The Don
Dodge Dakota
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2/15/2004
16:57:51
| RE: 4.7 Bent Valve
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I do still have the cams I think I will try again...just waiting for the weather to get warm again up here.
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DakUSA
DakotaEnthusiast
3/01/2004
10:43:38
| RE: 4.7 Bent Valve
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Well I will ad to this. I was going to do the HO swap and started the trear down only to find that cams in the box wee the wrong ones. So we put the stock one back in and put it all back together only for the pin to brake and jump time. When it did them it bent 2 valves on the drivers side. I have it all tore down now waiting on my head to get here tomarrow. Found a complete rebuilt head in dallas for 300.00 and I now have the right cams for I/ll be trying to put it all back together tomarrow.
Chris Lambert
Dakota USA
01 Graphite QC -- 4.7 Auto, Hotchkis, GTS Functional RamAir Hood, F&B 70mm TB, SpinTech True Dual Exhaust, Bed Rug, Leer 700, 18X9 Alt Wheels, SS Grilles, SS Bumper, Custon Leather seats, NR Auto gauges, Kenwood CD, 350 amp, JL 10" sub in console, DVD, Billit AC knobs
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TexasTodd
Dodge Dakota
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3/01/2004
12:40:10
| RE: 4.7 Bent Valve
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You sure they were the wrong cams? They do look different on one end. I know it's about impossible to see the lobe difference, but the ends, although work fine, do look different.
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Kowalski
Dodge Dakota
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3/01/2004
16:15:57
| RE: 4.7 Bent Valve
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It seems its not uncommon for them to screw up and send two of the same cams - don't know if that's what happened to Chris but they did it to me and I've heard of it with others. Cams for right and left in the 4.7 should be different lengths - if the same, one is wrong.
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DakUSA
DakotaEnthusiast
3/02/2004
10:04:32
| RE: 4.7 Bent Valve
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yea mine were the same. They send me one HO left and one non HO left. New cams should be here today along with the new head. Waiting on the special tool to home the chain and the head gaskets. I hope to have it running by tomarow night. Found a rebuilt head online at www.headsonly.com for 300.00 ready to install with a warenty. Comes with everything from cams down.
Chris Lambert
Dakota USA
01 Graphite QC -- 4.7 Auto, Hotchkis, GTS Functional RamAir Hood, F&B 70mm TB, SpinTech True Dual Exhaust, Bed Rug, Leer 700, 18X9 Alt Wheels, SS Grilles, SS Bumper, Custon Leather seats, NR Auto gauges, Kenwood CD, 350 amp, JL 10" sub in console, DVD, Billit AC knobs
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Kowalski
Dodge Dakota
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3/02/2004
15:46:20
| RE: 4.7 Bent Valve
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Sounds like a good deal - thanks for the link.
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