OK I'm working on a 68 FE 390 2 bbl backed by a C6 Mileage around 140,000 ? I pulled out of a field and am Getting her up and running. I have a noisy lifter , and have Ran some sea foam through her ETC It doesn't have the adjustable rockers, and I'm Considering installing them,.i know through a bit Of research that there is a difference in ratio . Between to 2. Set ups.would I use my existing push rods or do I Use one from a adjustable set up ? Also I may have bad lifter ? Is it OK to just replace the lifters With old cam. Thanks. Robb H
You would have to change the cam, lifters, pushrods and the rockers. Not a huge deal but does start to add up. IMHO I would keep the Hydraulic rockers and just change the cam, lifters and pushrods. This would save about $400-$500.
Before you tear into it, give it a good flush. Seafoam won't cut the mustard IMO, try 4 quarts of 10W30 and a quart of ATF. Run it for at least a 1/2 hour after it's reached full temp, then drain and change; at this point I'd swap to 20W40 oil. You should also check your oil pressure, if the pump is worn that can do it also.
You can use factory adjustable rocker arms with your stock cam & lifters, you would need the pushrods for adjustable rockers, as the non adjustable rockers use pushrods with balls on either end, while the adjustables use a ball on the bottom, with a cup on top, which works with the ball on the adjusting screw. However, if you do have a bad lifter, adjusting it won`t fix it. That said, its not uncommon for high milage FEs (or poorly maintained ones) to wear the ball ends of the pushrods badly enough to cause valvetrain noise.If I was you, my first step would be to remove the rocker shafts and pushrods, and take a close look. If the pushrod balls are round and smooth, they are probably OK, but worn pushrod balls usually take on a teardrop shape, often with a "nipple" at the end, if so, the pushrods are junk. New or good used pushrods may well cure the noise. Also look at the rocker arms, if the valve tips are noticably pitted, they should be replaced. If the tips look OK, slide the rockers over against the springs, and look at the shafts. If they are fairly smooth, great, but if they have large, rough grooves, no good. Keep track of the rocker shaft bolts, 1 on each bank is longer than the rest, and needs to stay in the proper position. The rocker stand mounting surface on each head will have 3 flat pads, and 1 with a countersunk hole. The longer bolt goes into the countersunk hole, that is how oil gets up to the rocker assemblies.
I agree with Rory428,but you can replace a lifter with a new one on a used cam,but never put used lifters with a new cam, if you decide to replace it,be carefull of what you buy,the market is flooded cheap offshore junk.stick with a trusted name brand.
If you can't get it flushed out I would just replace the noisy on as suggested. We used to have to replace noisy lifters on FE's under warranty all the time way back when. Except for the 4 corner lifters it's a pretty easy repair. Corner ones you have to fish them around a bit. Still a whole lot easier than replacing it w/an adjustable set up.
No you don't. The factory adjustable rockers (which are getting to be a little scarce) will work Fine with his stock cam and lifters. The only change other than the rockers is the pushrods, the ends are different. Have done this more than a few times including the 416" FE in my F150 right now. I would put a restrictor in the heads where the oil feeds the rockers though. These motors flow way too much oil to the rockers and the drain back in the heads is not very good. This keeps more oil at the crank and cam. The easiest way is a Holley Main jet, .040" to .080" in the feed hole under the rocker stand. One per head. Just slip it in, and the rocker pedestal holds it in place.
The main jet in the feed hole is a great idea. Also if you are going to tear into the motor, I would put hard seats on the exhaust.
Are you sure it's lifter noise? FE motors are notorious for knocking out the bushings on the top end of the connecting rod (wrist pin end). I thought I had a bad lifter on my wife's S code convertible Mustang but it turned out to be 2 connecting rods.
My 352 had a wrong bolt in a rocker shaft support when I bought it. Bolt was juat a little too long and bottomed out before it got tight.Every time the pushrods pushed on the rockers the support would raise a couple of thousanths and then bang back down. Sounded JUST like a bad lifter! I was pulling the rocker shafts to start changing out some lifters when I found it....
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