Timing belt job on a VVT car, now rattle on start up
#81
Ben, have you tried a brand new actuator from Mazda, or just continued to put used ones in it?
As I understand it, inside the actuator there is a spring-loaded pin which locks the actuator in place at start-up. Oil pressure then builds, fills the actuator, and un-locks the actuator once it's got enough oil pressure to operate. My assumption is that the pin is not locking the actuator, which means it's free to flop around until oil pressure builds up.
Acamas has this issue, I've had two used actuators in it so far. I've never had this issue with any other VVT motor (and I've been through a few). I currently have a brand new actuator on the shelf for it but I haven't gotten around to swapping it.
As I understand it, inside the actuator there is a spring-loaded pin which locks the actuator in place at start-up. Oil pressure then builds, fills the actuator, and un-locks the actuator once it's got enough oil pressure to operate. My assumption is that the pin is not locking the actuator, which means it's free to flop around until oil pressure builds up.
Acamas has this issue, I've had two used actuators in it so far. I've never had this issue with any other VVT motor (and I've been through a few). I currently have a brand new actuator on the shelf for it but I haven't gotten around to swapping it.
#83
The only parallel i can draw from experiences with other motors is that some years (early) KLs had some weird wave washer on the back intake (i think) cam, to help align the friction gears. Turns out it's really not necessary, it was replaced with a solid unit in later runs, but the early ones wear out, lose tension, and then rattle and sound shitty. Doesn't cause problems, just noise. Kindof sounds like this, but doesn't go away. (And the VVT noise is louder, slightly more rattle-y) Example here:
#85
I ran into this problem when I replaced my timing belt last year. I was getting a nice rattle at startup for just a few seconds. I remembered that I also had to install my spare valve cover when reassembling everything (including the oil control valve/solenoid that was already installed on it).
Doing some quick troubleshooting I started by swapping out the oil control valve with the one from my original valve cover. Turns out this was causing the rattle. I'm guessing that the seals in the valve may have dried out or slightly deteriorated while mounted to my spare valve cover that sat unused for a couple years.
Doing some quick troubleshooting I started by swapping out the oil control valve with the one from my original valve cover. Turns out this was causing the rattle. I'm guessing that the seals in the valve may have dried out or slightly deteriorated while mounted to my spare valve cover that sat unused for a couple years.
#88
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Swapped my oil control valve last night before going home. No rattle on startup last night. It did rattle briefly this morning, but it didn't rattle 3hrs later when I went to lunch. Not conclusive yet, but potentially promising.
#100
Hey gang,
My camshaft seals are leaking a bit, car seems to surge from 4K rpm and I've been getting P0012 ( "A" Camshaft Position - Timing Over-Retarded), which my research pointed to either dirty oil or VVT issue. I plan on doing oil change, cam seals, valve cover gasket, sparks and a few other items on NB2 soon and wanted to make sure I don't undo the wrong bolts and find myself is a similar predicament. Can anyone confirm which bolts I need NOT touch in order to keep actuator in one piece and not cause this headache?
I take it I need to remove the 3 Torx to expose the camshaft bolt, but NOT touch those 4 bolts around the main bolt holding it to the cam itself? Just unto the main one in the center and remove actuator as a single item?
My camshaft seals are leaking a bit, car seems to surge from 4K rpm and I've been getting P0012 ( "A" Camshaft Position - Timing Over-Retarded), which my research pointed to either dirty oil or VVT issue. I plan on doing oil change, cam seals, valve cover gasket, sparks and a few other items on NB2 soon and wanted to make sure I don't undo the wrong bolts and find myself is a similar predicament. Can anyone confirm which bolts I need NOT touch in order to keep actuator in one piece and not cause this headache?
I take it I need to remove the 3 Torx to expose the camshaft bolt, but NOT touch those 4 bolts around the main bolt holding it to the cam itself? Just unto the main one in the center and remove actuator as a single item?