JustEmptyEveryPocket Posted July 5, 2020 Share Posted July 5, 2020 I made some silly decisions and agreed to help a friend do some repairs. Long story short, I'm working with an 01 WJ 4.0L block with no head currently installed. Its out of the vehicle on a stand. I want to install the distributor (in place of the funky coil pack distributor thingy - no idea what its called -) since its easy to access out of the truck. And I'm lost on how to time it properly. I know normally you find TDC by watching the harmonic balancer and feeling for pressure from the #1 cylinder sparkplug hole. However, since I don't have the head on, how can I tell between compression stroke and exhaust stroke on #1? Most likely I am being dumb and overlooking something easy. Let me know how you would do this. Thanks in advance. Link to comment Share on other sites More sharing options...
Ωhm Posted July 5, 2020 Share Posted July 5, 2020 You need to know where the CAM timing is at. When CRANK/CAM timing marks are aligned, what position are the valves at for CYL#1? I'm not even sure if the CRANK/CAM timing marks are set for CYL#1. Link to comment Share on other sites More sharing options...
JustEmptyEveryPocket Posted July 5, 2020 Author Share Posted July 5, 2020 1 hour ago, Ωhm said: what position are the valves at for CYL#1 I can't know valve locations since the head is currently off of it. Unless I am missing something? Link to comment Share on other sites More sharing options...
Dzimm Posted July 5, 2020 Share Posted July 5, 2020 You have a 50/50 shot by just guessing. Otherwise stick the pushrods for cylinder one on the lifters and watch their position. Down will be valve closed, up will be valve opened. You could use a cardboard box to give them support if you have to as they may be too top-heavy to stand on their own, or have your buddy lightly keep them upright while letting them move up and down. For cylinder one the front pushrod is the exhaust valve and rear rod is intake. Turn it over and watch the rods move, when the cylinder is moving down the intake rod is also up, this will tell you the next time the piston moves up will be your compression stroke and thus be TDC at the top. Link to comment Share on other sites More sharing options...
Eagle Posted July 5, 2020 Share Posted July 5, 2020 2 hours ago, JustEmptyEveryPocket said: I can't know valve locations since the head is currently off of it. Unless I am missing something? Timing chain sprocket can only go on the crankshaft one way, and the sprocket is marked for aligning the chain to the cam sprocket. You're doing a 4.0L, so the cam is in the block even if the head is off. Look at the valve lifters. On the compression stroke, both will be down -- on the exhaust stoke, one will be up. Link to comment Share on other sites More sharing options...
JustEmptyEveryPocket Posted July 6, 2020 Author Share Posted July 6, 2020 On 7/4/2020 at 11:12 PM, Dzimm said: Otherwise stick the pushrods for cylinder one on the lifters and watch their position This is the super basic thing I was missing. Thank you very much. I made my best guess at timing and installed the distributor. At my working speed I will know if I made the right call in a few months when I try to start it Link to comment Share on other sites More sharing options...
Dzimm Posted July 6, 2020 Share Posted July 6, 2020 1 minute ago, JustEmptyEveryPocket said: This is the super basic thing I was missing. Thank you very much. I made my best guess at timing and installed the distributor. At my working speed I will know if I made the right call in a few months when I try to start it No problem, that's what we are here for! Hope everything works for ya, but from experience I'll say there will likely be something not working when you go to start it. Just the way it goes. Link to comment Share on other sites More sharing options...
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