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Re: 4.7 engine problem need help!
[Re: BigTerry]
#953349
03/19/11 11:40 AM
03/19/11 11:40 AM
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Joined: Jan 2003
Posts: 515
Bolingbrook, IL
HemiRunner
super street
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super street
Joined: Jan 2003
Posts: 515
Bolingbrook, IL
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Yes, that is a common problem on the 4.7's. they spit the rocker due to the lifter failing. Not a bad idea to replace all the lifters while you're in there. You will also need to check the lifter bore in the head as they sometimes break when the lifter fails & it spits the rocker. If this happens, it's time for a new head. There is a trick to replace them without pulling the cams & timing chains all the way out. Find the tighteneing sequence for the cam hold downs & a little at a time loosen them in the reverse order just enough to get the rocker/followers out or just off the lifter to replace the lifter. When all done make sure everything is lined up & carefully snug the cam hold downs back down in sequence & then follow the torque steps.
Blown & Injected, need I say more?
71 Road Runner
04 Dodge Ram 2500 4x4 CTD
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Re: 4.7 engine problem need help!
[Re: HemiRunner]
#953350
03/19/11 03:07 PM
03/19/11 03:07 PM
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Joined: Sep 2004
Posts: 6,906
IL, Aurora
ademon
master
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master
Joined: Sep 2004
Posts: 6,906
IL, Aurora
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Quote:
Yes, that is a common problem on the 4.7's. they spit the rocker due to the lifter failing. Not a bad idea to replace all the lifters while you're in there. You will also need to check the lifter bore in the head as they sometimes break when the lifter fails & it spits the rocker. If this happens, it's time for a new head. There is a trick to replace them without pulling the cams & timing chains all the way out. Find the tighteneing sequence for the cam hold downs & a little at a time loosen them in the reverse order just enough to get the rocker/followers out or just off the lifter to replace the lifter. When all done make sure everything is lined up & carefully snug the cam hold downs back down in sequence & then follow the torque steps.
At what milage are they failing? is it oil related?
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Re: 4.7 engine problem need help!
[Re: ademon]
#953351
03/19/11 05:15 PM
03/19/11 05:15 PM
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Joined: Jan 2003
Posts: 515
Bolingbrook, IL
HemiRunner
super street
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super street
Joined: Jan 2003
Posts: 515
Bolingbrook, IL
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I have seen them in the 50,000 to over 100,000 range, so it's not a specific mileage to look for. All the ones I have done are due to internal lifter failure & it has been anything from them colapsing to seizing up. The new lifters seem to be better, but only time will tell.
Blown & Injected, need I say more?
71 Road Runner
04 Dodge Ram 2500 4x4 CTD
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Re: 4.7 engine problem need help!
[Re: BigTerry]
#953356
03/20/11 10:14 AM
03/20/11 10:14 AM
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Joined: Aug 2010
Posts: 146
33950
67Monaco
member
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member
Joined: Aug 2010
Posts: 146
33950
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Yep, the 4.7 doesn't like heat. I lost a lower radiator hose driving home one night two blocks from the house. The temps went up, the heads warped enough to leak. $450 for the head work and polishing the cams. Gaskets, chains and other misc items were about another $400. Not too hard of a job overall just takes time is all.
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Re: 4.7 engine problem need help!
[Re: 67Monaco]
#953357
03/20/11 12:14 PM
03/20/11 12:14 PM
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Joined: Jan 2003
Posts: 515
Bolingbrook, IL
HemiRunner
super street
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super street
Joined: Jan 2003
Posts: 515
Bolingbrook, IL
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Another issue that plagues the 3.7 & 4.7 is carbon build up on the exhaust valves. Carbon builds up & hangs the valve open & spits the rocker. Pros & Cons of the 3.7 4.7. Pros Mopar engine, sort of. Cons Carbon build up on ex valve - spits rocker Ex seats fall out - spits rocker Lifter colapses/seizes - can break head, spits rocker Sensitive to overheating - warps head  what ya gonna do?
Blown & Injected, need I say more?
71 Road Runner
04 Dodge Ram 2500 4x4 CTD
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Re: 4.7 engine problem need help!
[Re: HemiRunner]
#953359
03/20/11 12:29 PM
03/20/11 12:29 PM
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Joined: Dec 2005
Posts: 341
New Jersey
U_Code_Cuda
enthusiast
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enthusiast
Joined: Dec 2005
Posts: 341
New Jersey
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WOW!! all these cons on the 4.7 and my 2000 Grand Cherokee has 233,000 with no engine or trans problems....  Any suggested maintenance to keep her alive longer
1970 R/T Challenger 4-speed
1971 Demon 340 3-speed
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Re: 4.7 engine problem need help!
[Re: U_Code_Cuda]
#953363
03/20/11 03:05 PM
03/20/11 03:05 PM
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Joined: Aug 2010
Posts: 146
33950
67Monaco
member
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member
Joined: Aug 2010
Posts: 146
33950
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Well the problem with mine wasn't bacuse of the quality of the engine it was the result of a faulty clamp on the lower hose. Other than that this engine has been perfect. I just replaced the chains while I had it apart since the 130K replacement was coming up. Other than that it's been running smooth as silk.
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