Engine Knocking after fresh oil
#61
After taking the cover off and looking at the green fluid on top I noticed two shades of green kinda swirled together. The coolant in the reservoir is red, in the radiator is green. Texted the PO and he says he added coolant just before he sold it to me. He knew it had a coolant leak and neglected to tell me... Oh well.
Now that you have the valve cover off, you can do this simple test:
Videos are a wonderful resource.
#62
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Year: 94
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No worries about not running the engine for awhile. I have a seperate vehicle as my DD. i never wanted to run the engine once it started knocking. That's why the videos so short, just thought a 30second video might help diagnose it more than 30seconds of running could hurt it.
#63
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Hey bud, just getting caught up again on your thread here. Hard to tell from the pics(4am pics, lol), but I watched the vid. As some others have stated, it sounds like top end noise, "rocker slap".
This can be caused by a collapsed lifter, bent pushrods, damaged/loose rocker, etc. Wiggle each rocker, some will be super tight(valve in open pos), some will have slight wiggle(closed), but none should be very loose. Check em all, bump the motor with the starter, check them again. Keep doing this till they've all gone through open/closed cycle.
If this doesn't yield an "AH HA!" moment, watch it in action. Being in an apartment, you don't want to run the motor with the cover off, this will make a pretty good mess. Pull the plugs(to eliminate compression), unplug the coil, and have a friend crank the engine while you watch the rockers. Pulling the plugs will allow the engine to free spin, letting the starter turn the engine fast enough to build oil pressure.
They should all cycle evenly, and you should see oil pumping from the small hole on each rocker.
You very likely have a head gasket in your future, but the good news is if that noise isn't bottom end, you probably have a saveable engine there.
This can be caused by a collapsed lifter, bent pushrods, damaged/loose rocker, etc. Wiggle each rocker, some will be super tight(valve in open pos), some will have slight wiggle(closed), but none should be very loose. Check em all, bump the motor with the starter, check them again. Keep doing this till they've all gone through open/closed cycle.
If this doesn't yield an "AH HA!" moment, watch it in action. Being in an apartment, you don't want to run the motor with the cover off, this will make a pretty good mess. Pull the plugs(to eliminate compression), unplug the coil, and have a friend crank the engine while you watch the rockers. Pulling the plugs will allow the engine to free spin, letting the starter turn the engine fast enough to build oil pressure.
They should all cycle evenly, and you should see oil pumping from the small hole on each rocker.
You very likely have a head gasket in your future, but the good news is if that noise isn't bottom end, you probably have a saveable engine there.
#64
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Year: 94
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The red could be rust or orange Dexcool antifreeze. I don't know about the newer improvements to antifreeze but its not recommended to mix the two. The green on the rocker I would say is antifreeze but you added lucas oil?
Now that you have the valve cover off, you can do this simple test:
Failed lifter - YouTube
Videos are a wonderful resource.
Now that you have the valve cover off, you can do this simple test:
Failed lifter - YouTube
Videos are a wonderful resource.
I know they make some coolants now that say "Will work with any color" hopefully thats what was chosen or I probably have a new radiator in my future too...
#66
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Yep 4am, and after another 4am pit stop at the XJ I learned the lifters don't have any play. So I'm guessing they're alright. This Sunday I'm gonna drop the oil pan and look for metal. Hopefully finding slim to none, but at this point... It's looking like the rods.
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Lol, I applaud your diligence. 4AM. I remember before I had a garage, I would get to my works shop building at 430 to time to run any electric, brakes, etc. Once my boss came in early at 6 while I was there stringing Christmas lights. He had to have known I wasn't right in the head bwahahahahaha
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out of curiosity, how does your oil pressure look? it seems odd that the lucas stayed in the rockers, even for only running 20 or 30 minutes.
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#71
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You can also take a sample of the oil and send it to blackstone labs for $25.00. That will tell you for sure if there are high levels of metals and coolant in your oil. The test kits are free. As for what filters to use, I would only use the recommended filters, I see a lot people recommending filters here without considering the specs for bypass rating, etc. I'm not talking about the WIX 51515, it is a suitable alternative but I have seen some recommended that are not.
Last edited by 9krpmrx8; 08-14-2015 at 04:08 PM. Reason: Spelling
#72
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Year: 94
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You can also take a sample of the oil and send it to blackstone labs for $25.00. That will tell you for sure if there are high levels of metals and coolant in your oil. The test kits are free. As for what filters to use, I would only use the recommended filters, I see a lot people recommending filters here without considering the specs for bypass rating, etc. I'm not talking about the WIX 51515, it is a suitable alternative but I have seen some recommended that are not.
*still hoping I can fix the knock though
Just nice to have a plan B
#74
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Year: 94
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Just wanted to say thanks to everyone.
One of the rods was loose. Hoped over to autozone picked up a new rod bearing, unfortunately I had to buy 6 not just 1. New bearing and some tightening down, no more knock.
I know I should have inspected/polished crank yada yada yada to ensure the bearing doesn't fail. But I've decided to get that $400 engine I mentioned before and start rebuilding it. Maybe even turning it into a stroker then dropping that in.
Jeep is ready to go and actualy went for a 2hr drive earlier just for kicks.
Thanks again to everyone that helped. [=
One of the rods was loose. Hoped over to autozone picked up a new rod bearing, unfortunately I had to buy 6 not just 1. New bearing and some tightening down, no more knock.
I know I should have inspected/polished crank yada yada yada to ensure the bearing doesn't fail. But I've decided to get that $400 engine I mentioned before and start rebuilding it. Maybe even turning it into a stroker then dropping that in.
Jeep is ready to go and actualy went for a 2hr drive earlier just for kicks.
Thanks again to everyone that helped. [=
#75
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Good to know. You could have run the engine at idle with the valve cover off for a few seconds and you might have noticed that. I had a rod that had come out from under the rocker and had a similar issue.
Kind of surprised people told you to change the oil filter. No filter is going to make that kind of difference. There's a lot of FRAM bashing on the internet but all companies that have been around change over time from good to bad to good etc. We all change our oil now more frequently than was ever done in the past and most of us always put a new filter in each time. Unless you're racing that Cherokee, or extrem off-roading, I can't see it making too much of a difference especially on an old vehicle.
I usually use a Wix oil filter, FRAM air filter, with the Champion plugs. Some people say Champions are only good in lawnmowers. Nuff said!
Kind of surprised people told you to change the oil filter. No filter is going to make that kind of difference. There's a lot of FRAM bashing on the internet but all companies that have been around change over time from good to bad to good etc. We all change our oil now more frequently than was ever done in the past and most of us always put a new filter in each time. Unless you're racing that Cherokee, or extrem off-roading, I can't see it making too much of a difference especially on an old vehicle.
I usually use a Wix oil filter, FRAM air filter, with the Champion plugs. Some people say Champions are only good in lawnmowers. Nuff said!