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1.9 modified rockers problems!

rah575554eg

rah575554eg

New member
Ok last weekend I install 1.9 modified rockers on stock springs, stock pushrods and stock lifters. I used new comp cam reuse bolts and tighten them to 11ft/lbs and 90* after the first click. I went to start it up and it was ticking pretty loud so I shut off and didn't run it again. I was told to check lifter preload and I measured around .158 so I was maxxing out on the lifters. So I switched back to the stock rockers and now when I went to start it up it idles ruff and backfires. I don't know what to do or whats causing it. My mods are basic ported blower and lim with mps 3.4", headers, cai, 160 stat, overkill pcm and tr8 plugs. Please help!
 




no loctite.

Clean the holes with q-tips, soak up all the oil in there. Then apply something like this: ZZ Performance

312_1.jpg


apply that to the bolt then torque to 23-25 ft lbs.

No extra 90*.
 
so you think that If I torque the stock rocker arms down to 25ft/lbs they would be fine? The ruff idle and backfire will go away?
 
rough idle and backfire might be something unrelated to the rockers, but the stockers should be fine with the comp or ARP bolts torqued to 25 ft lbs.
 
If your missing and backfiring it is for sure probably from the rockers...think about it Matt. Why wouldn't it? If the rockers are loose the valve isn't opening when it is supposed to or closing at the right time...

And yes, Loctite. It has been used on plenty of cars here...don't worry...there is nothing wrong with it.

Never had any issues...most of the time even if you do clean the holes your still going to have issues with the TTY or Comp bolts backing out. Use a dab of loctite and you won't have to worry about em.
 


Okay I did clean the holes out with q tips and used loctite red high strengh. I read the torque specs on the 11ft/lbs and 90*. They sure felt tight. I wonder if the pushrods got bent with the 1.9s.
 
You did it wrong....

torque to 25 ft lbs.

take the rods out and roll them on something flat and clean, you'll quickly be able to tell if they're true or not.
 
On the Crane Cams website it says if you have excessive lifter preload the engine will experiance backfire. I haven't checked the preload with the stock rockers but I must have excessive lifter preload now.
 


matt5112 said:
twenty-five (25) foot-pounds.
Click to expand...

quoted for truth. Pay attention to what people are telling you. 25ft-lbs. And no 90 degree rotation. The extra rotation is for torque to yield bolts.

Also, how long did you let the car run for once you changed to the 1.9's. Alot of times the lifters loose pressure and just have to pump back up so they'll cause all sorts of noise for a couple minutes.
 
Yes, mine ticked for half a minute or so. The backfiring is likely some mixed up wires (eg. incorrect firing order)
 
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