Timing chain replacement, can't turn crankshaft
#1
Timing chain replacement, can't turn crankshaft
I've got a 2001 1500 5.2L, 180K miles.
I've been working to replace my head gaskets and figured while I was at it, I would replace my timing chain (along with several other parts) as well.
I've got the heads off, along with everything needed to get to the timing chain.
Before removing the timing chain cover, I put the #1 cyl at TDC, as recommended by the Haynes book. When I removed the cover, I noticed that the timing marks on the cam and crank sprockets weren't aligned over top of each other. The mark on the crank was straight up 12:00 as expected, but the cam's mark was sitting at about 1:00.
Did a little research, and it looks like #6 is actually at TDC when the timing marks are in that position. So, I put the crank bolt back in and started turning the crank. When the mark on the cam sprocket got to about 5:00, the crank stopped turning for me. It won't budge. I haven't applied any force to try to move it past this point, and didn't think it should be necessary to do so since it was turning freely before.
How bad is this? Could the misaligned timing marks have something to do with this (i.e, would bad timing prevent the crank from turning?). Before I started the project, the truck was very drivable, just burning some coolant and idling rough (failed compression test on #1 cylinder, which started me down the head gasket path).
I can get the crank's timing mark back to 12:00. Should I do that and then remove whatever is needed to turn the cam freely (is that possible?), put the cam's timing mark in the correct position, tighten everything back up, and trying turning the crank again?
Or is it time to pull the engine and turn it over to a pro?
Thanks.
I've been working to replace my head gaskets and figured while I was at it, I would replace my timing chain (along with several other parts) as well.
I've got the heads off, along with everything needed to get to the timing chain.
Before removing the timing chain cover, I put the #1 cyl at TDC, as recommended by the Haynes book. When I removed the cover, I noticed that the timing marks on the cam and crank sprockets weren't aligned over top of each other. The mark on the crank was straight up 12:00 as expected, but the cam's mark was sitting at about 1:00.
Did a little research, and it looks like #6 is actually at TDC when the timing marks are in that position. So, I put the crank bolt back in and started turning the crank. When the mark on the cam sprocket got to about 5:00, the crank stopped turning for me. It won't budge. I haven't applied any force to try to move it past this point, and didn't think it should be necessary to do so since it was turning freely before.
How bad is this? Could the misaligned timing marks have something to do with this (i.e, would bad timing prevent the crank from turning?). Before I started the project, the truck was very drivable, just burning some coolant and idling rough (failed compression test on #1 cylinder, which started me down the head gasket path).
I can get the crank's timing mark back to 12:00. Should I do that and then remove whatever is needed to turn the cam freely (is that possible?), put the cam's timing mark in the correct position, tighten everything back up, and trying turning the crank again?
Or is it time to pull the engine and turn it over to a pro?
Thanks.
#2
#3
just curious when the crank is at 12 and the cam is at 1', whats the rotor in the dizzy point at? if its true TDC the rotor would be pointing towards #1. im not so sure you lookin at it on the wrong stroke. it will cycle twice before its on the compression stroke and at the real TDC. hopefully you understood that. if you cant get it to turn over by hand, hook the power back up and bump the ignition to get it over for ya. tiny bumps so you can get close to where you want it to be. then hopefully you can fine tune the marks by hand. just a thought.
#4
#5
#6
#7
@ Ham Bone: It's a replacement chain. Had it replaced about 100K ago.
I've applied a little more force than when it's turning easily. I haven't really leaned into it; wanted to play it safe until I learned more about possible causes. That being said, when it stops, it's pretty solid. It doesn't feel (to me) like something where just a little more force might free it.
I've attached a pic (https://dodgeforum.com/forum/attachm...1&d=1418657010) of the timing marks. It's not a straight-on view, but looking at it now, I don't know if the cam mark is as far away from 12 as I first thought.
Getting the timing marks lined up over top of each other is the goal now, but I'm not sure how to get there without being able to turn the crank.
I've applied a little more force than when it's turning easily. I haven't really leaned into it; wanted to play it safe until I learned more about possible causes. That being said, when it stops, it's pretty solid. It doesn't feel (to me) like something where just a little more force might free it.
I've attached a pic (https://dodgeforum.com/forum/attachm...1&d=1418657010) of the timing marks. It's not a straight-on view, but looking at it now, I don't know if the cam mark is as far away from 12 as I first thought.
Getting the timing marks lined up over top of each other is the goal now, but I'm not sure how to get there without being able to turn the crank.
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#8
looks like whoever did it was half a link off, not sure how this would play out since the timing is set by the computer, maybe it was within range for it to compensate. i would just go ahead and line it up how you have it and put the new crank on first and then do the chain and cam, and why is it at 12* on the cam? thought it was always 12 and 6. either way when you put it back on can you just make the cam dot at 6 or is it a balancing thing? all i know is when i did mine it was 12 and 6 likes all others i have ever seen. if the gear isnt balanced a certain way i would put it at 6, just personal pref.
#9
For the most part, when doing timing chain and gears, most folks don't move the distributor at all. (or, remove it for that matter) Having the dots at 12 and 6 make them easier to line up, but, that's about it. (and it puts number 6 in firing position....) Why they do it that way, is beyond me...
Don't use the crank bolt to turn the crank. Good way to break the bolt, then you REALLY have problems. I use a crescent wrench on the crank snout, and lock it against the woodruff key for the balancer to turn the engine. Works great, and no danger of breaking anything. (except a knuckle or two, if you don't have the crescent wrench tight enough..... keep that in mind. )
With the heads off, the engine should turn pretty freely. If it doesn't, you need to find out WHY. Do it now, while it is mostly disassembled already, rather than waiting till you have it put back together, and discover you get to take it back apart. May have to drop the pan, and see if anything under there is binding up.....
Don't use the crank bolt to turn the crank. Good way to break the bolt, then you REALLY have problems. I use a crescent wrench on the crank snout, and lock it against the woodruff key for the balancer to turn the engine. Works great, and no danger of breaking anything. (except a knuckle or two, if you don't have the crescent wrench tight enough..... keep that in mind. )
With the heads off, the engine should turn pretty freely. If it doesn't, you need to find out WHY. Do it now, while it is mostly disassembled already, rather than waiting till you have it put back together, and discover you get to take it back apart. May have to drop the pan, and see if anything under there is binding up.....
#10
looks like whoever did it was half a link off, not sure how this would play out since the timing is set by the computer, maybe it was within range for it to compensate. i would just go ahead and line it up how you have it and put the new crank on first and then do the chain and cam, and why is it at 12* on the cam? thought it was always 12 and 6. either way when you put it back on can you just make the cam dot at 6 or is it a balancing thing? all i know is when i did mine it was 12 and 6 likes all others i have ever seen. if the gear isnt balanced a certain way i would put it at 6, just personal pref.
Cam timing and ignition timing are two different things, and our motors are external balanced...But it does look a tooth off, and it should turn freely.
Time to find out why it's not.
Last edited by Adobedude; 12-15-2014 at 06:08 PM.