Rebuilt engine. when started again car ticks. timing marks aligned correctly, timing light shows 20 deg. what gives?

https://www.onlymanuals.com/hyundai/other_model/hyundai_diesel_engine_d4ea_workshop_manual_pdf

No, you don't need to remove the pully.

Here's how you set the timing:

You will need a timing light and a 1/2 inch or 13mm wrench.

1. Take a rag and clean the timing marks on the pulley and the timing cover. If you have any white out type correction fluid, you can also paint the marks white, to make them easier to see.

2. Start the engine and run until it is warm... about 5 minutes (the upper radiator hose will be warm).

3. Shut off the engine and find the timing connector, a grey plastic plug in the wiring harness near the distributor. Unplug the timing connector.

4. Loosen (but do not remove) the nut holding the distributor to the engine.

5. Connect your timing light. The magnetic pickup goes on the number 1 plug wire (number one is the front cylinder in your engine) and the other two leads connect to the battery, red on positive, black on negative.

6. Start the engine and point the timing light at the timing marks on the timing cover. You should be able to see the mark on the pulley as well. Gently rotate the distributor until the timing mark on the pully aligns with the 10 degree BTDC (before top dead center) mark. You might want to scribe a mark on your distributor before you start so that if you accidentally move the distributor too far and the engine dies, you can put it back where it was in order to restart the engine.

Once you have the timing set to 10 deg BTDC, shut the engine off, retighten the distributor nut and reconnect the timing connector.

remember 1 thing..dont confuse cam timing with ignition timing also if the belt or chain has alignment dots or marks on it ..it can be put on backwards and still line up marks correctly but but in a different position making the cam timming off i have done it and seen it done before like an old chevy when you put timming gear set on you line up the 2 dots alot of people think that is tdc and they set up ignition and go to start it and get pops and bangs well thats because the the install dots are actully 180 degrees out from tdc so you remove the distributor and turn it 180 deg. and now she starts right up i think you have 1 of these cams a tooth off or your using marks incorectly or belt or chain is backwards making dots align in different postion appearing correct

If you need further help, I’m available over the phone at https://www.6ya.com/expert/lee_9bf2e1a3cef596dc

Sounds like the timing is off or something wasn't synch'd up correctly during the rebuild. Check the timing and make sure the vacuum lines are connected correctly, especially the vacuum advance which advances your timing when the engine RPM's are increased. Start your timing at 5 degrees before top dead center, the 5 mark on your timing marks, this is the most common baseline setting for timing. If you have to set it advanced beyond 10 degree or retarded beyond 0 then your timing chain was not aligned correctly between the Pistons and the Valves or cam shaft.

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1. Remove the engine front cover. For additional information, refer to Engine Front Cover in this section.

1. Remove the crankshaft sensor ring from the crankshaft.

1. Rotate the crankshaft until the timing mark on the RH camshaft sprocket is approximately at the 11 o'clock position and the timing mark on the LH camshaft sprocket is approximately at the 12 o'clock position.

1. Using the special tool, position the crankshaft as shown.
   

1. Install the special tool.

1. NOTE: LH shown; RH similar.
   Remove the two bolts, the timing chain tensioner and tensioner arm.

1. Remove the LH and RH timing chains and the crankshaft sprockets.
   
   • Remove the special tool from the crankshaft.
   • Remove the timing chains from the camshaft sprockets.
   • Remove the right and left timing chains and the crankshaft sprocket from the crankshaft.

1. CAUTION: The bolts are different lengths and must be returned to their original location.
   NOTE: LH shown; RH similar.
   Remove the bolts and the timing chain guides.

Installation

1. CAUTION: Timing chain procedures must be followed exactly or damage to valves and pistons will result.
   CAUTION: Do not compress the ratchet assembly. This will damage the ratchet assembly.
   Compress the tensioner plunger, using an edge of a vise.

1. Using a small screwdriver or pick, push back and hold the ratchet mechanism.

1. While holding the ratchet mechanism, push the ratchet arm back into the tensioner housing.

1. Install a paper clip into the hole in the tensioner housing to hold the ratchet assembly and plunger in during installation.

1. Remove the tensioner from the vise.

1. NOTE: There are 61 links in the timing chain.
   If the copper links are not visible, mark two links on one end and one link on the other end, and use as timing marks.

1. Install the timing chain guides.

1. Using the special tool, verify correct crankshaft position.
   • Remove the special tool.

1. NOTE: Crankshaft sprockets are identical. They can only be installed one way. Refer to the following illustration for correct crankshaft sprocket installation.
   If removed, install LH and RH crankshaft sprockets.

1. Install the LH timing chain onto the crankshaft sprocket, aligning the one copper (marked) link on the timing chain with the slot on the crankshaft sprocket.

1. Position the LH timing chain on the camshaft sprocket with the two copper (marked) chain links and the camshaft sprocket timing mark aligned.

1. Position the RH (outer) timing chain on the crankshaft sprocket, aligning the copper (marked) link with the timing mark on the sprocket.

1. Position the RH timing chain on the camshaft sprocket. Make sure the two copper (marked) links align with the camshaft sprocket timing mark.

1. NOTE: LH shown; RH similar.
   Position the tensioner arms and tensioners, and install the bolts.

1. Remove the tensioner retaining clip.

1. As a post-check, verify correct alignment of all timing marks.

1. Remove the special tool.

1. Position the crankshaft sensor ring on the crankshaft.

1. Install the engine front cover. For additional information, refer to Engine Front Cover in this section.

Assuming the engine was re-assembled correctly with the all timing marks properly aligned, and the number 1 piston at top dead center in relation to the timing marks on the crankshaft, camshaft, and counterbalncing shaft, the computer sets the timing.
These are great engines, but they can be fun to work on, if you know what I mean.

A factory service manual would help, but I'm assuming that if you had one, you probably wouldn't be on this site.

To set the timing, you need to first perform the obvious: remove the accessory drive belts, cam pulley covers, and engine fan and hub. Next you'll need to rotate the engine by hand until the timing marks on the camshaft sprockets and crankshaft are aligned with their corresponding stationary marks. The 0 degree mark on the lower timing belt cover is the timing mark for the crankshaft pulley. There is a mark (small, vertical formed indentation) for the left camshaft pulley on the backing plate behind the pulley near the 1 o` clock position. The same mark exists for the right camshaft pulley only it is on the backing plate near the 8 o`clock position (making it difficult to see). With the crankshaft placed at the zero mark, you can observed where the timing discrepancy exists.

(TIP: Once the right camshaft timing is properly lined up, etch an additional mark on the pulley's face and the backing plate at the 12 o`clock position. This will make it easier to align the pulley for furture adjustments and repairs)

To set the timing correctly, move the crankshaft pulley to 12 deg. BTDC. Being careful to not disturb the position of the crankshaft once it has been moved to that position, remove the crankshaft pulley, lower timing belt cover, timing belt tensioner, and timing belt. Compress the timing belt tensioner and if the original ring pin isn't available to retain the tensioner a small allen wrench can be used to achieve the same results. Line up both camshaft marks and reinstall the timing belt and timing belt tensioner (do not remove the timing belt tensioner tool used to maintain the tensioner piston in a compressed position). When installing the timing belt, be sure to allow the least amount of slack to exisit between the left camshaft pulley and the crankshaft sprocket, but without moving the pulleys.

Next, remove the timing belt tensioner piston retention tool and mount the lower timing belt cover and crankshaft pulley (without fully installing them). Rotate the crankshaft pulley to the 0 deg. mark. If done correctly, moving the crankshaft pulley from 12 deg. BTDC to 0 deg. will remove all remaining slack from the timing belt assembly and the camshaft pulleys and crankshaft pulleys will be lined up with their corresponding marks. Once proper timing has been achieved, install all removed parts.

(Another TIP: I hope it's not necessary, but in case it is, I'll remind you that proper torque of all bolts are necessary as this is an all aluminum engine. Stripping out bolts holes due to over-tightening bolts occurs very easily and become very annoying to deal with [e.g. alternator belts not being able to be tightened completely and constantly squealing every few days, etc.])

Vacuum leaks. Check all hoses and intake bolts. Leaking EGR or plugged PCV valve. Air filter plugged. Leaking head gasket. Worn timing chain. Camshaft lobes worn. Valves burned or leaking. Fuel idle control system or sensor. Good luck!

The ECU will be fine with a engine rebuild but the 4JX takes a bit longer to start if all the injector oil paths are empty - can be up to 5 or 6 mins of 20 second cranking bursts.
Also if you rebuilt due to diesel in the oil from bad injectors the control valve for the injector oil pressure may be faulty so it wont start.

old timing belt stretched

you only hand turn twice

get number one cyl up on compression stroke both vales closed piston to top of stroke

put the cam with the tooth out to align marks

try again

unless you are 180 deg out should be right