| LOST JEEPS http://www.lostjeeps.com/forum/phpBB3/ |
|
| timing belt questions http://www.lostjeeps.com/forum/phpBB3/viewtopic.php?f=5&t=62798 |
Page 1 of 1 |
| Author: | marksjeeps [ Sat Sep 24, 2011 1:18 pm ] |
| Post subject: | timing belt questions |
Hello crd owners. Mark here with some questions about a timnig belt change. My camm gears won't line up to thier respected areas, as described in the various timing belt posting I've been following. My crd runs just fine and gets great fuel mileage, so I don't believe the belt has jumped any teeth. I've even highlight the cam and fuel pump tabs so as to not miss them as I rotate the engine. Does anyone suppose that someone has had the belt changed before, removed the cam gears and placed them incorrectly? Don't the cam gears have a key slot so there is only one position for them to seat? Any info is appreciated, Mark - 2005 crd/stock 120k miles. |
|
| Author: | papaindigo [ Sat Sep 24, 2011 2:07 pm ] |
| Post subject: | Re: timing belt questions |
I'm not quite sure what you are saying? I think what you are saying is the marks on the cam gears do not both line up at the same time with the adjacent marks on the rear cover when you rotate the engine, correct? If so I offer the following, subject to input from those more experienced than me. 1) there is no woodruff key associated with either cam gear; 2) the cams are apparently held in place on a tapered shaft by properly torqued cam gear retaining nuts; 3) given items 1 and 2 it is possible someone removed the cam gears (the only reason I know of is to replace the water pump) and reinstalled them without paying any attention to the marks BUT for that to be done without messing up the TB and destroying the engine the cams and flywheel would have to have been pinned in place. Given your question I am assuming you are not the 1st owner hence my first and strongest suggestion is to go back to the previous owner/mechanic and ask if the TB/water pump service was done. If you can confirm it was done than you can double check belt position by rotating the engine and seeing if you can install the 2 cam pins and the flywheel pin all at once (NOTE don't be fooled by the fuel pump mark as it only lines up on like every 3rd engine rotation - but the ideal line up would be the 3 pins in place with the fuel pump mark lined up). If that works out the cams were installed during service without paying attention to the marks and you will have to decide whether or not to pull them and reinstall. IMPORTANT if you cannot confirm that a TB/water pump service was done then I'd be inclined to consider a factory screw-up (unlikely but not impossible) and IMMEDIATELY operate on the assumption that you have a TB that needs replacement like now; in which case I'd do the service and reinstall the cams with things lined up as noted above. The latter may seem extreme but absent confirmation that you have a new TB best assume you don't as belts are cheap while rockers are not. You might PM/email Sir Sam and geordi both of whom are experienced with TB installs although geordi has not done the water pump. |
|
| Author: | Sir Sam [ Sat Sep 24, 2011 4:44 pm ] |
| Post subject: | Re: timing belt questions |
marksjeeps wrote: Hello crd owners. Mark here with some questions about a timnig belt change. My camm gears won't line up to thier respected areas, as described in the various timing belt posting I've been following. My crd runs just fine and gets great fuel mileage, so I don't believe the belt has jumped any teeth. I've even highlight the cam and fuel pump tabs so as to not miss them as I rotate the engine. Does anyone suppose that someone has had the belt changed before, removed the cam gears and placed them incorrectly? Don't the cam gears have a key slot so there is only one position for them to seat? Any info is appreciated, Mark - 2005 crd/stock 120k miles. Not quite sure what you are saying about "line up to thier respected areas" The marks on the cam gears do not correspond to anything in particular, in fact the orientation of the marks varies from vehicle to vehicle. There is no woodriff key that sets the cams to the cam gears. The only thing that times the cams is the cam locking pins that are inserted through the intake. The cam gear locking tool then times the cams relative to each other. |
|
| Author: | WolverineFW [ Sun Sep 25, 2011 2:57 pm ] |
| Post subject: | Re: timing belt questions |
Not quite following either. If you are doing your timing belt, you should be making your own marks on the engine and line everything back up with those. Don't trust what has been placed there earlier. |
|
| Author: | warp2diesel [ Sun Sep 25, 2011 8:38 pm ] |
| Post subject: | Re: timing belt questions |
There are several posts on how to change out a timing belt, Sir Sam has one method and has done it. Follow the procedure and you should be OK. The Why and Historical perspective: Due to the very precise orientation of the cam shafts and the slight varying in length of timing belts, block deck height, exact location of idler pulley mounting points,or cam bore holes in cylinder head, the camshafts are not keyed to the drive cogs. Instead, they use a tapered shaft on the cams with a tapered hole in the drive cogs, then the crank and cam shafts get placed in the exact location with the locking pins. VW uses a different method that works for locking the cam since day one with their diesel engines (pre TDI & TDI), but use the same tapered shaft and tapered hole type arrangement to get the cam timing correct. Before this solution was thought up, companies like Mercedes used off set keys to get the valve timing correct. |
|
| Author: | marksjeeps [ Mon Sep 26, 2011 1:04 pm ] |
| Post subject: | Re: timing belt questions |
Thinks to everyones info. Locating the the fly wheel position helped. The pin that goes in was what I was not doing. When inserted, I was able to place the cam pins in. The only thing is the bolt that holds the timing belt tensioner in place has come out when I was loosening it. It seems that a heli coil is whats used. Don't know if that's factory, but it will have to be fixed obviously. Thanks, Mark |
|
| Page 1 of 1 | All times are UTC - 5 hours [ DST ] |
| Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group http://www.phpbb.com/ |
|