compression test on 5.7 hemi
#2
#4
Did they do 2 tests or ran through it just once? You'd be surprised how much the numbers can change. Also, since the dealer is doing it, what was the problem you were having for them to do it in the first place? Have they done a leak down test to check the valves?
Those numbers aren't too far apart but are lower than they should be. A leak down test would be more helpful than a standard compression test.
#5
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Did they do 2 tests or ran through it just once? You'd be surprised how much the numbers can change. Also, since the dealer is doing it, what was the problem you were having for them to do it in the first place? Have they done a leak down test to check the valves?
Those numbers aren't too far apart but are lower than they should be. A leak down test would be more helpful than a standard compression test.
Those numbers aren't too far apart but are lower than they should be. A leak down test would be more helpful than a standard compression test.
Thanks...
https://dodgeforum.com/forum/3rd-gen...th-07-ram.html
#6
#7
Did they actually pull the heads to look at the valves and seats???
Sounds to me you need to run some heavy concentrate of Lucas Injector Fuel Stabilizer. I'm willing to bet you've got a bunch of carbon build up on your seat in that cylinder and it's giving a low or rather false reading. I hope so for your sake anyways. The sound of clacking tells me maybe your valves are sticking. Pour some Marvel Mystery oil in your crankcase for a few hundred miles and add some Lucas Injector cleaner to your tank. Run the entire tank and have your compression check & leak down test re-done. I would also say maybe the coil pack for that cylinder is bad or there is a bad ground. Change the plugs too.
http://store.summitracing.com/partdetail.asp?autofilter=1∂=LUC-10003-1&N=700+115&autoview=sku
http://cgi.ebay.com/MARVEL-MYSTERY-L...2em118Q2el1247
Sounds to me you need to run some heavy concentrate of Lucas Injector Fuel Stabilizer. I'm willing to bet you've got a bunch of carbon build up on your seat in that cylinder and it's giving a low or rather false reading. I hope so for your sake anyways. The sound of clacking tells me maybe your valves are sticking. Pour some Marvel Mystery oil in your crankcase for a few hundred miles and add some Lucas Injector cleaner to your tank. Run the entire tank and have your compression check & leak down test re-done. I would also say maybe the coil pack for that cylinder is bad or there is a bad ground. Change the plugs too.
http://store.summitracing.com/partdetail.asp?autofilter=1∂=LUC-10003-1&N=700+115&autoview=sku
http://cgi.ebay.com/MARVEL-MYSTERY-L...2em118Q2el1247
Last edited by dirtydog; 04-15-2009 at 11:15 PM.
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#8
#10
Just beware of that Marvel Mystery Oil. I had a V8 once with only 140k on it and added some in the crankcase. It broke loose all that carbon buildup and it drained to the oil galley in the block and pluged the drain holes to the pan so the pump pumped all the oil to the top of the motor and none was getting back to the bottom. In the end I ended up with a bad knock with 2 spun main bearings and one destroyed crank.
On a side note, I agree with how Dirty said to do the compression test but when you are getting a big difference in numbers arent you also supposed to add a small amount of oil on the combustion chamber and then do the test again to help seal the rings and check for gap (blow-by) issues?
On a side note, I agree with how Dirty said to do the compression test but when you are getting a big difference in numbers arent you also supposed to add a small amount of oil on the combustion chamber and then do the test again to help seal the rings and check for gap (blow-by) issues?