I need some help diagnosing an engine noise. My best guess is it’s a bad lifter, but I’m not an expert mechanic, and don’t know how to make a definite determination. Things are getting to the point where turning up the radio volume just isn’t helping any more. I just bought the jeep last year - It’s a stock 1994, 4.0 liter, AW4, daily driver in otherwise in good condition.
I’ve searched around here and learned a lot of good info about malfunctioning lifters, but I can’t tell for sure if that’s really what I have. Things have gotten really bad today, so a repair is imminent. I'd say that it's important to know exactly what's up before attempting to tear the top off the motor to replace the lifters (which I don’t know how to do, and I’m not looking forward to at all).
Bad noise #1 is a LOUD rough chattery click. It begins the second the engine starts, and only lasts for a moment. It will tick intensely eight or nine times in the space of 1.5 seconds, and then stop abruptly.
Bad noise #2 begins after the engine has run for only a minute; a second ticking noise fades in. This one is less noisy, a more gentle, sharp tapping that goes on for about five minutes, and then just stops suddenly after things have warmed up a bit.
Both of these happen on cold starts, especially in the winter. To fix this, I’ve tried some oil treatments. The last five oil changes have all been around 1500 - 2000 miles apart. Each of which I’ve added to the oil, with no success:
1- March: ATF added to Mobil-1
2- April: Seafoam/ Mobil-1
3- June: Auto-RX
4- July: Plain Castrol 10w30 - rinse phase for the Auto-rx,
5- Today: back to Mobil-1 5w30
NOW TODAY - things have become really bad. I put new oil in it this morning, and noise #2 started and did not go away. I drove it for a few hours and it stayed for the entire trip. It will fade in for a minute or two, then suddenly cut out, then fade back in again a minute later. I’m getting worried that things may be getting serious, and I can no longer put off doing an actual repair.
My Questions:
Thanks
:eyes:
I’ve searched around here and learned a lot of good info about malfunctioning lifters, but I can’t tell for sure if that’s really what I have. Things have gotten really bad today, so a repair is imminent. I'd say that it's important to know exactly what's up before attempting to tear the top off the motor to replace the lifters (which I don’t know how to do, and I’m not looking forward to at all).
Not long after I purchased the jeep, two engine noises started popping up:
Bad noise #1 is a LOUD rough chattery click. It begins the second the engine starts, and only lasts for a moment. It will tick intensely eight or nine times in the space of 1.5 seconds, and then stop abruptly.
Bad noise #2 begins after the engine has run for only a minute; a second ticking noise fades in. This one is less noisy, a more gentle, sharp tapping that goes on for about five minutes, and then just stops suddenly after things have warmed up a bit.
Both of these happen on cold starts, especially in the winter. To fix this, I’ve tried some oil treatments. The last five oil changes have all been around 1500 - 2000 miles apart. Each of which I’ve added to the oil, with no success:
1- March: ATF added to Mobil-1
2- April: Seafoam/ Mobil-1
3- June: Auto-RX
4- July: Plain Castrol 10w30 - rinse phase for the Auto-rx,
5- Today: back to Mobil-1 5w30
NOW TODAY - things have become really bad. I put new oil in it this morning, and noise #2 started and did not go away. I drove it for a few hours and it stayed for the entire trip. It will fade in for a minute or two, then suddenly cut out, then fade back in again a minute later. I’m getting worried that things may be getting serious, and I can no longer put off doing an actual repair.
My Questions:
- How can I determine EXACTLY what is causing the noise? (is it a lifter, or how can I tell if it’s something else?)
- If it is the lifter, how many miles can I drive before it starts to damage the engine? (Does a sticky lifter hurt the cam? Does a collapsed lifter cause lack of oil damage to the rockers?)
- Is there any other cure available without taking the engine apart?
Thanks
:eyes: