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Odd? knocking noise louder with good oil change

S

studmuffin

NAXJA Forum User
Location
El paso TX
Hey guys,

Well this is a bit odd, My PO did not change the oil too often so i decided to do a really good one. first i flushed the motor with motor flush, then i added five quarts of 10w40 and one bottle of lucas Synthetic, But what i find odd is that i use to have a knocking noise before but now i have a louder one after this change at idle,
was this too good of an oil change or Wat? lol
any info would help
 
when i bought my xj the po ahd not changed the oil regularly either and it was black and nasty, after changing it i ended up replacing the rad and crank bearings because of a knock, come to find out the po ahd used a mix of 80/90 to get the knock to go away which was a rod bearing knock, can u look in the valve cover and see if there is a lot of buildup? may ahve broke it loose and stopped up a oil passage, knock on top or bottom? does it go away after idle? alot of the 4.0 had a piston slap in them, if the oil pressure is good then let it be or try another flush, or try a hicker oil like 15/40, did u use synthetic oil? if so might try regular oil, is the filter dirty, after a flush i think u should cahnge the filter at least after a couple hundred miles good luck
 
dinorl007 said:
when i bought my xj the po ahd not changed the oil regularly either and it was black and nasty, after changing it i ended up replacing the rad and crank bearings because of a knock, come to find out the po ahd used a mix of 80/90 to get the knock to go away which was a rod bearing knock, can u look in the valve cover and see if there is a lot of buildup? may ahve broke it loose and stopped up a oil passage, knock on top or bottom? does it go away after idle? alot of the 4.0 had a piston slap in them, if the oil pressure is good then let it be or try another flush, or try a hicker oil like 15/40, did u use synthetic oil? if so might try regular oil, is the filter dirty, after a flush i think u should cahnge the filter at least after a couple hundred miles good luck
Click to expand...
well the oil pressure looks ok, either that or its broken, lol. but no i used regular oil just used that lucas sythetic and changed the filter too, and yeah during idling it knocks mostly in the beginning.:bawl:
 
dinorl007 said:
when i bought my xj the po ahd not changed the oil regularly either and it was black and nasty, after changing it i ended up replacing the rad and crank bearings because of a knock, come to find out the po ahd used a mix of 80/90 to get the knock to go away which was a rod bearing knock, can u look in the valve cover and see if there is a lot of buildup? may ahve broke it loose and stopped up a oil passage, knock on top or bottom? does it go away after idle? alot of the 4.0 had a piston slap in them, if the oil pressure is good then let it be or try another flush, or try a hicker oil like 15/40, did u use synthetic oil? if so might try regular oil, is the filter dirty, after a flush i think u should cahnge the filter at least after a couple hundred miles good luck
Click to expand...

Agreed he probably used a gear oil to hide the knock. It's probably toast to be honest.
 
robert2008 said:
Agreed he probably used a gear oil to hide the knock. It's probably toast to be honest.
Click to expand...
well not entirely sure because i did two oil changes before this one when i got the jeep so this started barely this time, i jus hope its not too bad of a problem, should i take it to a mechanic, lol...
 
I know when I decided to change oil to the Shell Rotella Synthetic 5w40, the Mobil-301 filter, and one of those tubes of Engine Treatment for 6 cylinder (don't remember the brand) I would have a real loud tick at start-up that would quickly fade away for a short while but after time I think the cleaner that knocked the gunk loose eventually ate through it and gave me back my oil pressure. I didn't know only 20-30lbs was bad at the time.

You could just try a few more flushes with cleaner and such. I've changed my oil about 4 times. Each time I run Seafoam through it and I still get synthetic oil to come out like it was straight dyno oil. I know that when I look through the fill port in my valve cover I am seeing shiny clean rocker arms now so I'm getting close to clean. Sometimes it just takes alot of time. Dropping your oil pan and cleaning all the gunk that has deposited at the bottom could help speed things up as well.
 
Fastdemise said:
I know when I decided to change oil to the Shell Rotella Synthetic 5w40, the Mobil-301 filter, and one of those tubes of Engine Treatment for 6 cylinder (don't remember the brand) I would have a real loud tick at start-up that would quickly fade away for a short while but after time I think the cleaner that knocked the gunk loose eventually ate through it and gave me back my oil pressure. I didn't know only 20-30lbs was bad at the time.

You could just try a few more flushes with cleaner and such. I've changed my oil about 4 times. Each time I run Seafoam through it and I still get synthetic oil to come out like it was straight dyno oil. I know that when I look through the fill port in my valve cover I am seeing shiny clean rocker arms now so I'm getting close to clean. Sometimes it just takes alot of time. Dropping your oil pan and cleaning all the gunk that has deposited at the bottom could help speed things up as well.
Click to expand...
Yeah i just checked my oil pressure and it is rather low, dont remember if it ever worked though since i only had it for three montha but i dont wanna risk it, do you suggest i just keep flushing it and flushing it, i think ill jus get wal mart brand and change it every couple of weeks cuz it gets expensive getting good oil, lol, and well finally after three changes ill put good high mialage oil and the lucas. what type of oil and how thick do you recommend i should use?
 
10w30 for normal driving. There are conversations all about the right oil for the temperature the vehicle runs in. Thicker for hotter and thinner for colder. I was a little mad when I ran the engine treatment stuff through cuz after about 500 miles the oil was already black and I had just spent good money on the synthetic stuff. Oh well. Just right before you change it dump some seafoam in the oil and idle it for about 10mins then let the engine cool and drain it. Should help remove even more buildup. But like some have experienced if you remove too much carbon there is a chance you'll start to consume oil. Since it was the carbon that was holding the seal. Ive done it a few times and have not experienced such misfortune.
 
Last edited:
Fastdemise said:
10w30 for normal driving. There are conversations all about the right oil for the temperature the vehicle runs in. Thicker for hotter and thinner for colder. I was a little mad when I ran the engine treatment stuff through cuz after about 500 miles the oil was already black and I had just spent good money on the synthetic stuff. Oh well. Just right before you change it dump some seafoam in the oil and idle it for about 10mins then let the engine cool and drain it. Should help remove even more buildup. But like some have experienced if you remove too much carbon there is a chance you'll start to consume oil. Since it was the carbon that was holding the seal. Ive done it a few times and have not experienced such misfortune.
Click to expand...
so i can put seafoam in the oil, from what i heard its not good in the oil, only in the brake booster and in the gas. wow how much should i put, should i flush it again.
 
you are putting seafoam in the oil only right before you change it. Do no drive with it in the oil because it's like paint thinner(not really) and it destroys the protective/lubrcating properties of the oil.
 
I did the flush & change routine about 3 times with my old '88 Renix, then it started to tick. So I pulled the valve cover and re torqued the rockers. The difference was night and day, the tick went away and I could rev a little higher before I got the valve floatin noise. Also you could take and drain your oil and leave the plug out. Then pour a fresh quart in and see how long it take to get back down to the plug. When I did the valve cover a bunch of carbon/sludge was built up around the oil return passages. If the oil isn't getting back down to the pan it will cause the mains to go dry and cause a knock and low oil pressure. Also check and see if you have oil in the air box.
Well hope this helps good luck. :)
 
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