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Lou P.
Lou P., ASE Certified Technician
Category: Car
Satisfied Customers: 4605
Experience:  I Have knowledge in almost all car lines and can help with general questions and more!!!!!
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I am replacing the timing chain tensioner bolt in a 2004 ecotec.

Customer Question

I am replacing the timing chain tensioner bolt in a 2004 ecotec. I have recieved an updated part number and am unsure as to the procedure to load the tensioner after it is installed...I know you could hit the head of the old style to load it, but do you do this to the new style as well? the part # XXXXX XXXXX
Submitted: 7 years ago.
Category: Car
Expert:  Lou P. replied 7 years ago.
you do not need to load the new tensioner you just need to screw it in. the tensioner head should be bottomed out. the procedure for loading is only done when your reusing the old tensioner and have replaced all rails and chain and gears.
Customer: replied 7 years ago.
so after I install the new one how do I get it to release tension on the chain?
Expert:  Lou P. replied 7 years ago.
well let me ask you why are you replaceing this and do you have any other components removed form the engine??
Customer: replied 7 years ago.
due to timing chain noise and no other parts are off the engine..I had removed the valve cover and replaced the guide between the cams due to it having failed now i need to know about the bolt...i have removed the old one and want to install the new one..I just received some info from GM and want to see if you have the same ideas or something else to add about how to release the bolt to put tension back on the chain.
Expert:  Lou P. replied 7 years ago.
ok i have done one of these what happens is the chain wears down the gears and rails so since you have the valve cover off you can see if it puts enough tension on the guide whne installed. what will happen is if it does not put tension on the new guide when installed your going to have to replace the rest of the peices. i bought a kit from autozone that had both rails, cam and crank gear, chain, and tensioner and unless all those were installed i could not get the tensioner to keep tension. so try just installing it as it is and see if it takes up slack in the chains.
Customer: replied 7 years ago.
Thanks...not really what I was asking for help with..I will have to get back to you in a bit..I will try the GM fix and see if that works.
Expert:  Lou P. replied 7 years ago.
well what im trying to tell you is that you dont need to do any setting of the new tensioner if all other parts are ok. what is it you are hearing from gm??
Expert:  Lou P. replied 7 years ago.

here's the process for priming the tensioner:

24. If the timing chain tensioner is not in the compressed state, perform the following steps:

24.1. Remove the piston assembly from the body of the timing chain tensioner by pulling it out.
24.2. Install the J 45027-2 (2) into a vise.
24.3. Install the notch end of the piston assembly into the J 45027-2 (2).
24.4. Using the J 45027-1 (1), turn the ratchet cylinder into the piston.
25. Inspect the bore of the tensioner body for dirt, debris, and damage. If any damage appears, replace the tensioner. Clean dirt or debris out with a lint free cloth.
26. Install the compressed piston assembly back into the timing chain tensioner body until it stops at the bottom of the bore. Do not compress the piston assembly against the bottom of the bore. If the piston assembly is compressed against the bottom of the bore, it will activate the tensioner, which will then need to be reset again.
27. At this point the tensioner should measure approximately 72 mm (2.83 inch) (a) from end to end. If the tensioner does not read 72 mm (2.83 inch) (a) from end to end repeat steps 16.1 and 16.4.


this is what i found .