How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Shimell Your Own Question
Shimell, Nissan and ASE Master technician
Category: Nissan
Satisfied Customers: 363
Experience:  18 years with Nissan. Nissan and ASE master technician with advanced ASE certification.
Type Your Nissan Question Here...
Shimell is online now
A new question is answered every 9 seconds

I have an 04 Sentra 1.8 QG18DE engine and had to

This answer was rated:

I have an ''04 Sentra 1.8 QG18DE engine and had to replace the head gasket due to leaking coolant into #3 and #2 cylinders. I am now replacing the timing chain and trying to rotate the crank by hand with the chain installed, but it will only rotate about 1/2 of a turn in either direction until it reaches a hard, solid metallic stop. The exhaust, intake and crankshaft will rotate freely each on its own, but not when joined together by the chain. I think I have all the timing marks lined up with the correct links on the chain at top dead center on the compression stroke, but I did not mark them before disassembly. I also did not advance the variable valve timing sprocket on the intake cam (don''t have a compressor to produce the 40 PSI needed). Should the crank be able to freely rotate with both cams linked with the timing chain? Can anyone help? Thanks in advance, John.

your timing chain is out of time. you are hitting the valves.

here is a diagram for the timing chain setup.

you align the colored mar on the chain with the alignment mark on the pulley as show in the diagrams.


Shimell and 4 other Nissan Specialists are ready to help you
Customer: replied 9 years ago.
Reply to Shimell's Post: What about my taking off the intake sprocket without advancing the variable value timing? Did I wreck it? I'm I going to need to purchace a new one or might it just be ok? Will I have to reassemble and just see how (if)it runs?
Thanks for your help so far!

you need to re assemble it in the correct time, then see if it is ok then.

dont wory too much about the timing advance thing. just make sure you line up the marks where they are sopposed to be on the sprocket.

DO NOT take apart the sprocket. you can take it off the camshaft, but DO NOT take it apart.

make sure your colored marks on the chain match the spots on the gears.

carefully read this diagram.graphic
Customer: replied 9 years ago.
Reply to Shimell's Post: Thanks so much for all your help, it was very useful.