manifolds are good. Also, the reason for the oil pump change is because the oil pressure completely falls off after about 10 minutes of running and the engine is hot. Although, that is why I was running 20w50....as that oil seemed to hold decent oil pressure. I am hoping (as the Jeep mechanic told me) that the oil pressure will be fixed with the new oil pump.
'89 Jeep Wranger 6 cyl
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Originally Posted By: BigJohn
Also, the reason for the oil pump change is because the oil pressure completely falls off after about 10 minutes of running and the engine is hot. Although, that is why I was running 20w50....as that oil seemed to hold decent oil pressure. I am hoping (as the Jeep mechanic told me) that the oil pressure will be fixed with the new oil pump.
99% of the low oil pressure problems are from worn bearings. Since it's a sludge monster and you had to clean the pan out with a spoon I would suspect worn bearings.
Don't forget the cam bearings too.
Also, the reason for the oil pump change is because the oil pressure completely falls off after about 10 minutes of running and the engine is hot. Although, that is why I was running 20w50....as that oil seemed to hold decent oil pressure. I am hoping (as the Jeep mechanic told me) that the oil pressure will be fixed with the new oil pump.
99% of the low oil pressure problems are from worn bearings. Since it's a sludge monster and you had to clean the pan out with a spoon I would suspect worn bearings.
Don't forget the cam bearings too.
Jeep oil pumps have about 150K +/- lifespan, which you have exceeded (based on experience with Jeeps, friends, + clubs). I think you'll be fine with the new pump. On my '92 Wrangler trail rig (2.5L), I Tee'd a mechanical gauge in with the factory one. There is a difference. In the very least, hook up only the mechanical gauge and see what the pressure is after 10 minutes of driving. Jeep factory oil pressure gauges aren't the best.
I would also try running a tank of 93 gas to help that knock if it persists after the oil pump install. Carbed 258's don't distribute fuel as evenly as EFI, so cylinder 1 + 6 may run leaner than ther others. That BBD carb probably doesn't help matters, but if it runs OK, then leave it. I really wish I had video of my friends Jeep. As the 93 gas displaced the old fuel in the float bowl, you could hear the knock go away. It was truly amazing.
Regarding your filter, I forgot the 258's used the metric one (A Fram PH3985 equivalent) and not a FL300.
BTW, while you're in there, you might as well replace the rear main. It' cheap and easy. I also highly recommend the Felpro one-piece rubberized oil pan gasket. It has the torque rings at each bolt hole. It's awesome. I have done about 8-9 rear main seals on 258's, 4.0L's, and my 2.5L. Not one leak a drop of oil. This gasket alone cuts your repair time.
Let us know how you make out. Good luck.
*We need a Jeep wave icon*
I would also try running a tank of 93 gas to help that knock if it persists after the oil pump install. Carbed 258's don't distribute fuel as evenly as EFI, so cylinder 1 + 6 may run leaner than ther others. That BBD carb probably doesn't help matters, but if it runs OK, then leave it. I really wish I had video of my friends Jeep. As the 93 gas displaced the old fuel in the float bowl, you could hear the knock go away. It was truly amazing.
Regarding your filter, I forgot the 258's used the metric one (A Fram PH3985 equivalent) and not a FL300.
BTW, while you're in there, you might as well replace the rear main. It' cheap and easy. I also highly recommend the Felpro one-piece rubberized oil pan gasket. It has the torque rings at each bolt hole. It's awesome. I have done about 8-9 rear main seals on 258's, 4.0L's, and my 2.5L. Not one leak a drop of oil. This gasket alone cuts your repair time.
Let us know how you make out. Good luck.
Once you're done with your repairs, I would change the oil to a 5W-30 and run Marvel Mystery Oil as per their directions for 1000 miles and change it out along with the filter. OR You could do an A-Rx clean rinse.
Frank D
Frank D
Originally Posted By: Zaedock
I would also try running a tank of 93 gas to help that knock if it persists after the oil pump install. Carbed 258's don't distribute fuel as evenly as EFI, so cylinder 1 + 6 may run leaner than ther others. That BBD carb probably doesn't help matters, but if it runs OK, then leave it. I really wish I had video of my friends Jeep. As the 93 gas displaced the old fuel in the float bowl, you could hear the knock go away. It was truly amazing.
Unfortunately, my son filled up with gas just before this job, so we will have to wait a week or so before we can add the 93....but I am definitely doing that.
Also, I suppose I should have sprung for the one piece gasket, but it was about $30 and I got the cork/rubber combo for $11. Since there were two of us working on the gasket, I think we got it positioned perfectly.....hopefully no leaks.
Unfortunately, we hadn't prepared to do any other work on the Jeep over the holiday weekend, so we weren't prepared to do the rear main and anything else...... Maybe next time. Hopefully, this will help the oil pressure issue and solve the knocking!!!!
I would also try running a tank of 93 gas to help that knock if it persists after the oil pump install. Carbed 258's don't distribute fuel as evenly as EFI, so cylinder 1 + 6 may run leaner than ther others. That BBD carb probably doesn't help matters, but if it runs OK, then leave it. I really wish I had video of my friends Jeep. As the 93 gas displaced the old fuel in the float bowl, you could hear the knock go away. It was truly amazing.
Unfortunately, my son filled up with gas just before this job, so we will have to wait a week or so before we can add the 93....but I am definitely doing that.
Also, I suppose I should have sprung for the one piece gasket, but it was about $30 and I got the cork/rubber combo for $11. Since there were two of us working on the gasket, I think we got it positioned perfectly.....hopefully no leaks.
Unfortunately, we hadn't prepared to do any other work on the Jeep over the holiday weekend, so we weren't prepared to do the rear main and anything else...... Maybe next time. Hopefully, this will help the oil pressure issue and solve the knocking!!!!
Look what viscosities recommended for these blocks back in the '73 by AMC... After some contemplation of corresponding temp. ranges for 5w 20 and 20w 20 viscosities, 20w 50 doesn't look OK below 32°F and 10w s doesn't look OK below 0°F.
http://www.oldcarmanualproject.com/manuals/AMC/1973/Service/Part1/A-B/browser.htm
If we assume the above data is applicable, while the 0w 20 isn't out of question, 5w 40 or some 5w 50 is the best viscosities until the pump is fixed.
http://www.oldcarmanualproject.com/manuals/AMC/1973/Service/Part1/A-B/browser.htm
If we assume the above data is applicable, while the 0w 20 isn't out of question, 5w 40 or some 5w 50 is the best viscosities until the pump is fixed.
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Originally Posted By: BigJohn
Originally Posted By: Gary Allan
....Most of the problems with 4.0/4.2 are typically valve noise ..
Need some more advice on this noise..... The engine sounds like a diesel engine when the RPM's are at idle to about 2500, and then it disappears as the engine is reved. Also, the oil pressure gauge reads a high level until the engine heats up and then the oil pressure dips.
A local Jeep mechanic told my son that the first fix would be a new oil pump....hence our 'shade treeing' this weekend.
What do you think?
The problem, if you call it that, is that you don't get to adjust the preload on the lifters. It's fixed by the bridged rockers. Not that this is a problem in itself, but it relies on on the lifters falling into some uniform variable of manufacture and durability in use. You also can't change them out like you can on the 2.5 without pulling the head.
The engine doesn't typically have the Niagara Falls oil flow to the lifters/top end.. like (something like) a SBC. That's why (my speculation) when the neglect takes hold ..the lifters are the first evidence the problems. You may or may not have had enough pressure/flow to the lifters. If they all were clacking at cold start ..and continued to make noise until warm ..then it's a varnish deal where the flow isn't right until the oil is thin enough. Now if a few clack cold ..and all make noise at hot idle ..then it is probably an oil pressure problem that can be solved with a pump. You'll still probably be plagued with the cold start noise until you clean them up.
Originally Posted By: Gary Allan
....Most of the problems with 4.0/4.2 are typically valve noise ..
Need some more advice on this noise..... The engine sounds like a diesel engine when the RPM's are at idle to about 2500, and then it disappears as the engine is reved. Also, the oil pressure gauge reads a high level until the engine heats up and then the oil pressure dips.
A local Jeep mechanic told my son that the first fix would be a new oil pump....hence our 'shade treeing' this weekend.
What do you think?
The problem, if you call it that, is that you don't get to adjust the preload on the lifters. It's fixed by the bridged rockers. Not that this is a problem in itself, but it relies on on the lifters falling into some uniform variable of manufacture and durability in use. You also can't change them out like you can on the 2.5 without pulling the head.
The engine doesn't typically have the Niagara Falls oil flow to the lifters/top end.. like (something like) a SBC. That's why (my speculation) when the neglect takes hold ..the lifters are the first evidence the problems. You may or may not have had enough pressure/flow to the lifters. If they all were clacking at cold start ..and continued to make noise until warm ..then it's a varnish deal where the flow isn't right until the oil is thin enough. Now if a few clack cold ..and all make noise at hot idle ..then it is probably an oil pressure problem that can be solved with a pump. You'll still probably be plagued with the cold start noise until you clean them up.
Finished the oil pump job this evening and...oh my goodness....what an improvement. Not only is the oil pressure constant and strong, but the knock at idle has disappeared. Unfortunately, there is still a knock somewhere between 2k and 2.5k RPM's, although it isn't nearly as loud.
Here is what we poured in the engine:
1 quart Rislone
4 quarts of 5w20 dino (only had 4 quarts)
1 quart of 5w30 dino
We also poured 4 oz's of Marvel Mystery Oil in the gas tank, hoping to clean things up in the fuel system as well.
Here is what we poured in the engine:
1 quart Rislone
4 quarts of 5w20 dino (only had 4 quarts)
1 quart of 5w30 dino
We also poured 4 oz's of Marvel Mystery Oil in the gas tank, hoping to clean things up in the fuel system as well.
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When you get the chance, check the timing chain slack. Just turn the engine by hand until the distributor rotor moves, then turn it the other way until it moves again. I think you're allowed 12 degrees of slack measured at the crank (iirc).
Good luck!
Good luck!
Originally Posted By: BigJohn
Finished the oil pump job this evening and...oh my goodness....what an improvement. Not only is the oil pressure constant and strong, but the knock at idle has disappeared. Unfortunately, there is still a knock somewhere between 2k and 2.5k RPM's, although it isn't nearly as loud.
Here is what we poured in the engine:
1 quart Rislone
4 quarts of 5w20 dino (only had 4 quarts)
1 quart of 5w30 dino
We also poured 4 oz's of Marvel Mystery Oil in the gas tank, hoping to clean things up in the fuel system as well.
That's great news! I'm glad the pump worked out. When I installed the latest 2.5L into my YJ, I used a Melling high volume pump. On a hot day, I have 40psi at "odd angles"
That 5W20 will work fine for winter (what brand did you use?). My concern was fuel dillution with the BBD, but at 15+/- *F, it'll be like 90 weight gear oil 'til it warms up anyway.
I've always like MMO and that should help clean up your intake valves. If/when your BBD carb dies, check into a Motorcraft 2bbl swap. Many guys up here run them and they work well and are much cheaper than an EFI swap.
Happy Trails!
Finished the oil pump job this evening and...oh my goodness....what an improvement. Not only is the oil pressure constant and strong, but the knock at idle has disappeared. Unfortunately, there is still a knock somewhere between 2k and 2.5k RPM's, although it isn't nearly as loud.
Here is what we poured in the engine:
1 quart Rislone
4 quarts of 5w20 dino (only had 4 quarts)
1 quart of 5w30 dino
We also poured 4 oz's of Marvel Mystery Oil in the gas tank, hoping to clean things up in the fuel system as well.
That's great news! I'm glad the pump worked out. When I installed the latest 2.5L into my YJ, I used a Melling high volume pump. On a hot day, I have 40psi at "odd angles"
That 5W20 will work fine for winter (what brand did you use?). My concern was fuel dillution with the BBD, but at 15+/- *F, it'll be like 90 weight gear oil 'til it warms up anyway.
I've always like MMO and that should help clean up your intake valves. If/when your BBD carb dies, check into a Motorcraft 2bbl swap. Many guys up here run them and they work well and are much cheaper than an EFI swap.
Happy Trails!
Originally Posted By: BigJohn
We also poured 4 oz's of Marvel Mystery Oil in the gas tank, hoping to clean things up in the fuel system as well.
Glad to hear you had some improvement. With regard to MMO in the gas. Here is what works best, according to my experiences and speaking with someone at Turtle Wax about it. Get a good FI cleaner and run a tankful through it first. Then treat with MMO at a rate of 4 oz/10 gallons of fuel. The MMO will work a lot better after you treat the engine with a FI cleaner.
At your next OC you might consider adding a qt of MMO and running it for 1000 miles and dump it. Or run A-Rx as directed. I'm pretty sure there's going to be a lot more gunk in that engine, and with the new pump I would suggest removing it slowly.
JMO,
Frank D
We also poured 4 oz's of Marvel Mystery Oil in the gas tank, hoping to clean things up in the fuel system as well.
Glad to hear you had some improvement. With regard to MMO in the gas. Here is what works best, according to my experiences and speaking with someone at Turtle Wax about it. Get a good FI cleaner and run a tankful through it first. Then treat with MMO at a rate of 4 oz/10 gallons of fuel. The MMO will work a lot better after you treat the engine with a FI cleaner.
At your next OC you might consider adding a qt of MMO and running it for 1000 miles and dump it. Or run A-Rx as directed. I'm pretty sure there's going to be a lot more gunk in that engine, and with the new pump I would suggest removing it slowly.
JMO,
Frank D
Originally Posted By: BigJohn
Originally Posted By: Gary Allan
....Most of the problems with 4.0/4.2 are typically valve noise ..
Need some more advice on this noise..... The engine sounds like a diesel engine when the RPM's are at idle to about 2500, and then it disappears as the engine is reved. Also, the oil pressure gauge reads a high level until the engine heats up and then the oil pressure dips.
A local Jeep mechanic told my son that the first fix would be a new oil pump....hence our 'shade treeing' this weekend.
What do you think?
In my '93, with 243k miles, this worked repeatedly and I never completely figured out why, but made night and day difference...
Put whatever oil you want. I tried maxlife, rotella, rotella T, whatever. Then add 1/2 qt syntec 5-20. Cut the lifter noise in half every time.
Having cleaned 1/2" of sludge from the top end of a 4.0L, I can tell you with confidence that NO OIL WILL clean up severe accumulated sludge, and that includes the run of the mill otc cleaners [censored] well. Tried it, cleaned it, own the t-shirt. Didn't try ARX.
M
Originally Posted By: Gary Allan
....Most of the problems with 4.0/4.2 are typically valve noise ..
Need some more advice on this noise..... The engine sounds like a diesel engine when the RPM's are at idle to about 2500, and then it disappears as the engine is reved. Also, the oil pressure gauge reads a high level until the engine heats up and then the oil pressure dips.
A local Jeep mechanic told my son that the first fix would be a new oil pump....hence our 'shade treeing' this weekend.
What do you think?
In my '93, with 243k miles, this worked repeatedly and I never completely figured out why, but made night and day difference...
Put whatever oil you want. I tried maxlife, rotella, rotella T, whatever. Then add 1/2 qt syntec 5-20. Cut the lifter noise in half every time.
Having cleaned 1/2" of sludge from the top end of a 4.0L, I can tell you with confidence that NO OIL WILL clean up severe accumulated sludge, and that includes the run of the mill otc cleaners [censored] well. Tried it, cleaned it, own the t-shirt. Didn't try ARX.
M
We are going to closely monitor the oil that is in the engine currently. If it goes "black" in a hurry, then we are going to change it at that time....one week, two weeks, a month....three months....who knows.
I also like Rotella 5w40 Synthetic...but unsure at this time. I have some oil on the garage shelf that needs to be used, so that will probably be the next two fills.
I also like Rotella 5w40 Synthetic...but unsure at this time. I have some oil on the garage shelf that needs to be used, so that will probably be the next two fills.
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BigJohn:
Just change the filter. If you're going to be doing multiple oil changes in a very short time, the expense in wasted motor oil over shadows something like Auto-Rx. You've already got a bona fide sludge condition ..and while solvent like flushes are inviting, the wasted oil that you're going to add up due to the limited time that you can leave them in the sump ..well..it just makes the cost of the stuff more sensible.
In any event, if you go with something like RTS or whatever, get your money's worth out of it and just change a $2-$3 filter every so often. I'd cut one open to see what's in it.
You'll be going through gallons of oil in a very short time if I read the leanings that I'm seeing here.
Just change the filter. If you're going to be doing multiple oil changes in a very short time, the expense in wasted motor oil over shadows something like Auto-Rx. You've already got a bona fide sludge condition ..and while solvent like flushes are inviting, the wasted oil that you're going to add up due to the limited time that you can leave them in the sump ..well..it just makes the cost of the stuff more sensible.
In any event, if you go with something like RTS or whatever, get your money's worth out of it and just change a $2-$3 filter every so often. I'd cut one open to see what's in it.
You'll be going through gallons of oil in a very short time if I read the leanings that I'm seeing here.
Good tip on the high octane gas to reduce the knocking. My son has reported that the knocking has all but disappeared.
By the way, we are starting our second week on the current oil fill.....and I think we will change this coming weekend.
Everything seems to working very well.
By the way, great tip on just changing the oil filter, we will do that in the next few days. I will also cut open the filter to see what is inside. Cheers!!!
By the way, we are starting our second week on the current oil fill.....and I think we will change this coming weekend.
Everything seems to working very well.
By the way, great tip on just changing the oil filter, we will do that in the next few days. I will also cut open the filter to see what is inside. Cheers!!!
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