1500 mi. on lifters, now a tick...new info HELP!

**red mistress** · 11-28-2007, 02:41 PM

Lifters

when you adjusted did you go extra 1/4, 1/2 or 3/4 turn?

were hydraulic lifters pumped up? Meaning engine was pre-lubed with screwdriver spinning in the dizzy hole?

easy to pop valve cover off and crank engine to listen which ones are loose.

If you don't want oil all over the place, follow manual sequence for adjusting all.

**TLF** · 11-28-2007, 03:48 PM

Originally posted by red mistress

when you adjusted did you go extra 1/4, 1/2 or 3/4 turn?

were hydraulic lifters pumped up? Meaning engine was pre-lubed with screwdriver spinning in the dizzy hole?

easy to pop valve cover off and crank engine to listen which ones are loose.

If you don't want oil all over the place, follow manual sequence for adjusting all.

I'm not sure I understand what you're asking me about the extra 1/4, 1/2, or 3/4 turn adjustment.

I did remove the left valve cover and there sure isn't anything loose in there. I ran it with the cover off and sort of think I narrowed it down to cyl. #1, not sure which valve. I think maybe I'll have a peek at the right side before I do anything else.

**AMX factor** · 11-28-2007, 04:08 PM

The tick could be several things besides a lifter. Slightly bent pushrod, spring bad, rocker arm cracked or bent, crack in exhaust manifold ticks like a lifter also. I just don't see the lifter going bad so quickly.

**Crazy_Jeepman** · 11-28-2007, 04:09 PM

There is no rocker adjustment on an AMC motor, you torque the rockers to 19 FT LBS and that is it.
I have never had good luck replacing just the lifters on a high mileage motor, it usually turned out to be a bandaid fix at best.
There are several things I would be looking at now at this point
#1 is what kind of oil pressure do you have.
#2 check for bent pushrods
#3 The suspect lifter: measure the rocker travel with a dial indicator, and compare it with a rocker where the lifter is not making any noise. This will tell you if you have worn down the lifter and/or the cam lobe.
#4 check that relaxed valve heights are the same

**Kris** · 11-28-2007, 05:18 PM

Exhaust leak.

Dont assume the worst. Check your manifolds.

k.

**TLF** · 11-28-2007, 06:30 PM

Get this s**t. Got done tinkering with it for the evening and was moving it from shop to garage (daily driver at the moment). While in the driveway I was trying to study the noise a little better, revving it a little and what have you. Thought I'd power brake it a little to see if the noise changed any, perhaps pointing me more toward an exhaust leak, then what? Driveshaft breaks. Not a pleasant noise, but at least I was in the driveway and not on the highway. Further inspection revealed that someone had done some sort of "fixing" on it in the past. It looked like a round window had been cut out of it and then welded back in. Sweet.

**Mahamotorworks** · 11-28-2007, 06:43 PM

Originally posted by TLF

Driveshaft breaks. Not a pleasant noise, but at least I was in the driveway and not on the highway.

True.

Now you have more time to fond out what is going on.

MAHA

**red mistress** · 11-28-2007, 06:43 PM

roller rockers

I thought the engine was built with roller rockers. oops..... Glad the shaft fell out on drive. When I was 17 was rolling along fast in my 73 Bronco and rear shaft let go (thankfully) at diff. Bent exhaust and floor.

**TLF** · 12-04-2007, 04:54 PM

OK, driveshaft issue is handled but I'm still exploring my tick which has gotten worse yet. Here's the condensed version of what I know: It's cyl #1, most likely exhaust valve. As of today it has new rockers, pivots, and a bridge (and of course the new lifters a few months ago). Relaxed valve spring height is the same for both valves and as the cyl. next door. Intake/exhaust pushrods are the same length, but when seated on the lifters, the intake pushrod sticks out of the head about 1/16th further than the exhaust pushrod. Here's the part I don't like. When installing the rockers, exhaust lifter preload is essentially zero. This makes me think that either my new lifter already has excessive wear on the bottom, or that cam lobe is badly worn, or both.

Anybody got any input/suggestions? Please!?! Tell me I've overlooked something simple.

**byson1** · 12-05-2007, 07:31 AM

Get a cheap dial indicator and measure the lift on the rockers as you turn the motor over by hand. This will tell you if a cam lobe is going/gone flat. Another way I have checked unknown rocker/lifter noises is to simply start the motor up with he valve cover off and visually look at the movement. Depending on you oil pressure this can be a little messy. My best educated guess based on what you've said is a lobe going flat. It's become a little more common now days since the most "new" oil formulas don't contain some of the crucial additives needed for flat tappet lifters.

**gojeepin** · 12-05-2007, 07:57 AM

i fear the worst for you,i had a crane cam rep tell me years ago that installing new lifters on an old cam will cause the cam to go flat,on the other hand i have seen a few people do it without trouble

**hutchman** · 12-05-2007, 08:49 AM

From what you describe, it certainly sounds like a flat cam. I thinks this is fairly common when replacing lifters. I had a new Trans Am have a cam go flat back in 1979. The dealership replaced the cam and lifter/lifters unde warranty and I took the car home. Less than thirty miles later the engine had seized and had spun 3 rod bearings and a main bearing.

Lesson learned: When a cam goes flat, you shouldn't just replace the cam and lifters. The metal from the cam has to go somewhere and Murphy says it will go to the place that will do the most damage. You will need to completely overhaul the engine.......ouch!

**TLF** · 12-05-2007, 09:27 AM

Yeah, I've got a bad feeling about the cam. The thing that kind of confuses me though is that it runs great and has tons of power for a stock motor. Seems like if the cam is going I should notice some other ill effects... We'll see. Thanks for your thoughts everyone.

**hutchman** · 12-05-2007, 09:47 AM

The Trans Am that I had with the flat cam started back firing through the carburator under load. It was obvious something was wrong.

byson1 makes a good point on oils.......the newest API rated oils may not provide adequate lubrication for older flat tappet cam designs. There are many articles on the internet concerning this issue. We could get into an oil discussion, but that would be a whole different topic.

1500 mi. on lifters, now a tick...new info HELP!