Timing Chain Tensioner
03-10-2019, 03:26 PM
#22
New Member
Join Date: 03-09-2019
Location: Florida
Posts: 29
I've got the belt and I just ordered a new tensioner. The belt has been changed before but the tensioner is original so it is probably due anyway. I've run in to enough things that don't really make sense and since we are not talking about a major operation or a lot of money, I'll change them out and see if it works. I've learned that I can pull the valve cover off now in about 20 minutes so I see no excuse for anyone trying to change the timing chain tensioner without pulling the cover to insure that it has extended, as well as checking the guides for wear and damage. I appreciate all of the help and when the tensioner comes in and I get it installed, I will post the results.
Thanks to all that offered help.
Thanks to all that offered help.
03-18-2019, 07:17 AM
#24
New Member
Join Date: 03-09-2019
Location: Florida
Posts: 29
I changed out the serpentine belt and installed a new tensioner for it. Not a fun job but no special tools were needed. I used a standard 3/8" breaker bar and a ratchet strap to hold the tensioner while I put the serpentine belt on. It made no difference to the start-up rattling. I did pull of the inspection cover and the other chain is tight.
I listened again to the sound while the wife started the engine this morning. It sounds like valve clatter at the top of the engine for just a second or two and then it stops. To me it has a stronger sound than perhaps a loose chain would have. As the picture showed, and my physical inspection verified, the chain is not loose and the guides do not appear to be worn. As mentioned, I had also changed the timing chain tensioner.
This is the VVT engine. Is there anything in the valve train that is unique to this engine that could cause a cold start-up rattle after only 51,000 miles?
My next trial is to possible start the engine with the valve cover off to get a visual inspection on start up. Not sure how much oil would fly around.
I should add that right after the noise was verified, I shut the engine down. A minute or two later I tried starting the engine again cold and no rattle. I am guessing it is something that rattles when the lubricating oil drains out of the area.
According to the one source, Chevrolet is recommending that their mechanics replace the cam phasers and then clean or replace the actuators. This is fine for a dealership where the mechanic can just throw parts at a problem until the noise goes away. For me, following those GM recommendations would cost me $300 in parts plus lost time for my labor. My thinking right now is that noise in the cam phaser can only cause wear in the cam phaser itself. Maybe I would be just as well off ignoring the noise until it affects the driveability of the HHR. Any comments, pro or con, with just ignoring the noise issue until the engine stumbles?
From the TSB:
Condition/Concern:
In rare instances a technician may comment they hear a short, sharp rattle noise from the front of the engine on start up.
Recommendation/Instructions:
If the noise is from the front accessory drive area, inspect the engine belt. We have seen concerns with engine belts causing a loud ticking type noise. If found, verify power steering pulley outer edge is aligned flush with shaft and repair as needed. If pulley alignment is correct replace the engine belt.
If the noise is still present and is very short and sharp in duration (2-5 seconds) This may be an issue with the cam phasers not parking properly. Once the noise is verified as the phasers, they must be replaced. If the cam phasers are replaced, remove the CMP actuator solenoids to inspect for debris. If debris is found clean and inspect for torn or loose screens and replace if necessary.
Note: If debris is found in the solenoids and phasers change the oil and filter before returning to service, in some instances it may be necessary to change the oil/filter multiple times with a test drive in between each. The filter and solenoids can be inspected afterwards to ensure no additional debris is present.
Here is the quote from the TSB:
I listened again to the sound while the wife started the engine this morning. It sounds like valve clatter at the top of the engine for just a second or two and then it stops. To me it has a stronger sound than perhaps a loose chain would have. As the picture showed, and my physical inspection verified, the chain is not loose and the guides do not appear to be worn. As mentioned, I had also changed the timing chain tensioner.
This is the VVT engine. Is there anything in the valve train that is unique to this engine that could cause a cold start-up rattle after only 51,000 miles?
My next trial is to possible start the engine with the valve cover off to get a visual inspection on start up. Not sure how much oil would fly around.
I should add that right after the noise was verified, I shut the engine down. A minute or two later I tried starting the engine again cold and no rattle. I am guessing it is something that rattles when the lubricating oil drains out of the area.
According to the one source, Chevrolet is recommending that their mechanics replace the cam phasers and then clean or replace the actuators. This is fine for a dealership where the mechanic can just throw parts at a problem until the noise goes away. For me, following those GM recommendations would cost me $300 in parts plus lost time for my labor. My thinking right now is that noise in the cam phaser can only cause wear in the cam phaser itself. Maybe I would be just as well off ignoring the noise until it affects the driveability of the HHR. Any comments, pro or con, with just ignoring the noise issue until the engine stumbles?
From the TSB:
Condition/Concern:
In rare instances a technician may comment they hear a short, sharp rattle noise from the front of the engine on start up.
Recommendation/Instructions:
If the noise is from the front accessory drive area, inspect the engine belt. We have seen concerns with engine belts causing a loud ticking type noise. If found, verify power steering pulley outer edge is aligned flush with shaft and repair as needed. If pulley alignment is correct replace the engine belt.
If the noise is still present and is very short and sharp in duration (2-5 seconds) This may be an issue with the cam phasers not parking properly. Once the noise is verified as the phasers, they must be replaced. If the cam phasers are replaced, remove the CMP actuator solenoids to inspect for debris. If debris is found clean and inspect for torn or loose screens and replace if necessary.
Note: If debris is found in the solenoids and phasers change the oil and filter before returning to service, in some instances it may be necessary to change the oil/filter multiple times with a test drive in between each. The filter and solenoids can be inspected afterwards to ensure no additional debris is present.
Here is the quote from the TSB:
Last edited by rgatijnet; 03-18-2019 at 09:22 AM.
03-18-2019, 09:29 AM
#25
Administrator
Join Date: 10-13-2011
Location: Welland,Ont Canada
Posts: 36,455
If it is the cam phasers, $300.00?
https://zzperformance.com/products/cam-phasers
Id go this route. Leaving it and ignoring the noise is never a good idea!
While you have your hands oily install one of these,
https://zzperformance.com/search?q=guide+bolt
https://zzperformance.com/products/cam-phasers
Id go this route. Leaving it and ignoring the noise is never a good idea!
While you have your hands oily install one of these,
https://zzperformance.com/search?q=guide+bolt
03-18-2019, 09:45 AM
#26
New Member
Join Date: 03-09-2019
Location: Florida
Posts: 29
The $300 is for both the cam phasers and the actuators. Actually it will probably be more for the parts if I go with ACDelco at about $109 each for the phasers and $35 each for the actuators plus tax and shipping.
I do agree that ignoring a noise is never a good idea. I also do all of my own work on my private airplane and nothing gets your attention quicker than a strange noise. The difference is that I have to deal with gravity in the plane vrs a minor inconvenience with the HHR. I hate throwing parts at a problem until it goes away but there doesn't seem to be a way to determine which one or if both cam phasers is bad. Maybe there is a way but at a dealership, it saves time(and money) to just replace the part, charge the customer, and move on to the next project. Replacing the bolt seems like a good idea.
I do agree that ignoring a noise is never a good idea. I also do all of my own work on my private airplane and nothing gets your attention quicker than a strange noise. The difference is that I have to deal with gravity in the plane vrs a minor inconvenience with the HHR. I hate throwing parts at a problem until it goes away but there doesn't seem to be a way to determine which one or if both cam phasers is bad. Maybe there is a way but at a dealership, it saves time(and money) to just replace the part, charge the customer, and move on to the next project. Replacing the bolt seems like a good idea.
03-18-2019, 10:47 AM
#29
Administrator
Join Date: 10-13-2011
Location: Welland,Ont Canada
Posts: 36,455
Perhaps it’s just enough to make noise until oil pressure builds .
If you or the PO had the timing chain changed , is it plausible a bolt wasn’t torqued correctly
I do recall a member who had a noise at start up.
I remember it was the Crankshaft bolt was loose.
Now, that could be the source , but I think the cam phaser should be able to test them, like take off the timing chain, and try moving them gently, are either one making a similar noise, feel loose? Maybe those camshaft bolts aren’t torqued correctly either?
If you or the PO had the timing chain changed , is it plausible a bolt wasn’t torqued correctly
I do recall a member who had a noise at start up.
I remember it was the Crankshaft bolt was loose.
Now, that could be the source , but I think the cam phaser should be able to test them, like take off the timing chain, and try moving them gently, are either one making a similar noise, feel loose? Maybe those camshaft bolts aren’t torqued correctly either?
03-18-2019, 11:01 AM
#30
New Member
Join Date: 03-09-2019
Location: Florida
Posts: 29
When I opened the engine, that was the first time it have ever been opened. I guess it is always possible that a bolt was not torqued properly at the factory on both the crank and cams. . Timing change, as well as all internal parts are original with 51,000 miles and I just recently changed the timing chain tensioner. The one I took out was the new style with no apparent problems.