How does this system work
Looking for information regarding the VVT phasers, we have a new short block and reman heads, New chains, guides, and tensioner's , this has a rattle cold start, like lifters or timing chain, leaning towards timing chain, seems louder in the front cover This has a subaru oil filter. No codes drive nicely. I read that the cam phasers can possibly cause this type of noise. The description was a little un clear, I'm not sure if they are to be locked with engine off. Or are they supose to be unlocked? That is, the cams can be rotated a little without the sprockets moving.
Any other suggestions are appreciated
Refer to TSB 02-157-14R, and pay close attention to page 16. It refers to the importance of preloading the timing chain tensioners during assembly. Not performing this step can cause exactly the symptoms you've mentioned.
Great tip! I just checked STIS to see if the service manual had the same instructions. It didn't. Gotta check for TSBs I guess. Subaru actually has some really great service information, but it's not always found the service manual. A lot of times you'll only find what you need in the Technician Reference Booklets and TSBs.
Thanks for that heads up. I try to look for tsb's when I do any timing chain work. I would have seen this tsb, concerning engine oil comsumption, and I would have looked past it.
I agree with Leo about preloading the tensioners. These chains will rattle unless you got that extra click out of the tensioners after pulling the grenade pin.
I'm not 100% sure about your exact engine, but most of the Subaru VVT sprockets I've played with have a spring-loaded lock pin that prevents movement until oil pressure releases it. That said, it looks like Leo probably solved your issue.
The tsb mentioned doesn't come up in Alldata, it states it was superceded, the superceded one isn't available, what I did last night was manually activated the solenoids I can hear them click, then I started the engine and activated them a few times. This morning there was no noise. Did it the tensioner get the extra click or the phaser was sticking? I'll keep trying the cold start to verify…
Hi Fred, Here's a copy from STIS. Although I did see it in Alldata as well (see screen cap).