In my opinion if you have lifter noise (and you are sure it is), mileage is over 100,000, and you are going to rip off the top of the engine and remove the lifters. why would you not just replace them. Really 10 bucks each is a small price to prevent possibility of re-occurrence.

Document ID# 49760
1997 Pontiac Bonneville

Valve Lifter Noise Diagnosis

<A href="http://127.0.0.1:9001/servlets/BlobShtml?ShtmlFile=49760&evc=sm&pubid=43&cellId=4 1865&mspsdsubkey=330#tab1-46408">Momentary Noise On Engine Startup

Step
Action
Value(*)
Yes
No
DEFINITION: Valve train noise disappears after 1 to 2 minutes
1
This condition is normal. Oil drains from the lifters which hold the valves open when the engine is not running. The valve lifter needs a few seconds to fill with oil after you start the engine.
Did you allow the valve lifters to fill?
--
No correction is needed
--
<A href="http://127.0.0.1:9001/servlets/BlobShtml?ShtmlFile=49760&evc=sm&pubid=43&cellId=4 1865&mspsdsubkey=330#tab1-46409">Intermittent Noise on Idle Only

Step
Action
Value(*)
Yes
No
DEFINITION: Intermittent noisy on idle only, disappears when engine speed increases
1

1. [*]

Are the lifters dirty? Are the lifters damaged?
--
Go to Step 2
System OK
2
Replace the valve lifter. Refer to Valve Lifter Replacement
--
--
--
<A href="http://127.0.0.1:9001/servlets/BlobShtml?ShtmlFile=49760&evc=sm&pubid=43&cellId=4 1865&mspsdsubkey=330#tab1-46475">Noise at Slow Idle

Step
Action
Value(*)
Yes
No
DEFINITION: Noisy at slow idle or with hot oil; quiet at higher engine speeds or with cold oil
1
Inspect the valve lifter for high lay down rate.
Does the valve lifter have a high leakdown rate?
--
Replace the faulty valve lifter
No correction is needed
<A href="http://127.0.0.1:9001/servlets/BlobShtml?ShtmlFile=49760&evc=sm&pubid=43&cellId=4 1865&mspsdsubkey=330#tab1-46476">Lifter Noise at High Vehicle Speeds

Step
Action
Value(*)
Yes
No
DEFINITION: Valve lifters noisy at high vehicle speeds, quiet at low speeds
1
Check for a high engine oil level. An oil level above the FULL mark allows the crankshaft counterweights to churn the engine oil into foam. When foam is pumped into the valve lifters, the valve lifters become noisy since a solid column of oil ensures proper operation.
Is the engine oil level too high?
--
Drain the engine oil to the proper level
Go to Step 2
2
Check for a low engine oil level. Oil level below the ADD mark allows the oil pump to pump air at high speeds. This causes noisy valve lifters.
Is the engine oil level too low?
--
Add engine oil as required
Go to Step 3
3
Check the oil pan.
Is the oil pan bent against the oil pump pickup?
--
Repair as required
Go to Step 4
4
Check the oil pump screen.
Is the oil pump screen bent or loose?
--
Repair as required
System OK
<A href="http://127.0.0.1:9001/servlets/BlobShtml?ShtmlFile=49760&evc=sm&pubid=43&cellId=4 1865&mspsdsubkey=330#tab1-46477">Noise at Idle, Becomes Louder at High Engine Speed

Step
Action
Value(*)
Yes
No
DEFINITION: Noisy at idle, becoming louder as engine speed increases to 1500 RPM
1
This noise is not connected with lifter malfunction. The noise becomes noticeable in the vehicle at 10 to 15 mph L (Low) range, or 30 to 35 mph D (Drive) range. The noise is described as a "ticking" sound. At slow idle, the sound may be entirely gone or appear as a light ticking noise in one more valves. This noise is caused by one or more of the following:

• Badly worn or scuffed valve tip and rocker arm pad.
• Excessive valve stem-to-guide clearance.
• Excessive valve seat runout.
• Off-square valve spring.
• Excessive valve face runout.

Are any components damaged or worn excessively?
--
Repair as necessary
Go to Step 2
2
The noise may be an off-square valve spring. You can eliminate this noise by rotating the valve spring and valve.

1. [*]

The valve spring should not be more than a 1.6 mm (1/16 in) off-square.
Is the valve spring off-square?
--
Replace valve spring
System OK
<A href="http://127.0.0.1:9001/servlets/BlobShtml?ShtmlFile=49760&evc=sm&pubid=43&cellId=4 1865&mspsdsubkey=330#tab1-46479">Valve Noise Regardless of Engine Speed

Step
Action
Value(*)
Yes
No
DEFINITION: Valve lifter noise louder as engine speed increase hot or cold engine.
1

1. [*]
2. [*]

Is the valve pushrod upper end ball worn?
--
Replace the valve pushrod and valve rocker arm
Go to Step 2
2
Check for a bent valve pushrod.
Is the valve pushrod bent?
--
Replace the valve pushrod
Go to Step 3
3
Check the lubrication system feed to the valve pushrod and check to see if the valve pushrod is properly lubricated.
Is the valve pushrod and feed system properly lubricated?
--
Go to Step 4
Replace the valve pushrod and valve rocker arm
4
Check for a loose or damaged valve rocker arm.
Is the valve rocker arm loose or damaged?
--
Replace the valve rocker arm
Go to Step 5
5
If you do not need to replace the valve pushrod or the valve rocker arm, this indicates trouble in the valve lifter or camshaft.
Is the camshaft worn or damaged?
--
Replace the camshaft and valve lifters
Replace the valve lifter(*) as necessary

Document ID# 49760
1997 Pontiac Bonneville

Because there are 12 of them, so that'* $120 plus shipping. That'* a tough pill to swallow when you consider you're already replacing the LIM gaskets by going down that far ($30), and the pushrods as well ($20). If you can inspect them and verify they're all in good condition, there should be no need to replace them.

As for the lack of tools and experience, I did the job with a $20 cheap set of tools and a haynes manual the first time. Took me about 4 hours. Now I can pull the LIM and put it back in an hour or less. Its not a very big job. It doesn't require a lot of experience, just overcoming the fear of what you don't know. Just keep track of which bolts go where (egg carton, ziploc bags) if you're really concerned with it.

If you lived nearby, I'd help you do it. I'm in the southwest Chicago suburbs. Its not a very big deal at all. If you want, I can post the steps on here.

Because of the cost involved, I'm going to have to slowly buy everything one piece at a time. Now I'm looking at pushrods, that ported LIM, and metal LIM gaskets for sure. Lifters, too, if any are still noisy after cleaning. Looks like I've got a long-term project on my hands.

Time to start planning things out. Looking forward to this rebuild/upgrade. Maybe I'll learn something.

Someone has lifters brand new in the box for the 3800 for sale somewhere don't they? I remember seeing a set.

For sale section. I was interested in them as well until he mentioned that 3800 lifters rarely just flat out fail, and that he'* never seen one fail. I've gotten many more reports of worn pushrods causing problems and ticking noises. Fortunately those are cheap.

IIRC he was asking $90 for them.

BTW, when you order everything, RockAuto.com is your friend. Don't forget to do a quick google search for the latest 5% discount code. They always have one available.

Just thought of something that might make this easier. In 1500 miles, I have to do this job myself. If you'd like, I can take pictures along the way and post them so you know what to expect.

The most I've done (without Bill'* help) under the hood is change the spark plugs. Pictures would be great. At least it would let me identify broken parts.

I'll get you pictures of the steps you'll need to take from start to finish.