sludge found now have engine knock
- Thread starter jrc2905
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Open the upper intake manifold and hand clean as much out as possible. Seal it back up and do an Auto-Rx. Or if your really handy can do a carb clean soak which will get rid of most of whats on it while soaking(you need a bucket filled with carb clean and soak the part in it).
Using a heavy 10 minute cleaning agent won't do you good since you will flush a lot of it at once maybe doing more harm than good.
My Jeep with 200k and very wild OCI changes(on time with me, rarely on time with my brother driving it) and now i have been doing the maintenance with the slow and steady method as it was pretty wicked in there(no sludge I could see but not the cleanest engine on the planet).
Using a heavy 10 minute cleaning agent won't do you good since you will flush a lot of it at once maybe doing more harm than good.
My Jeep with 200k and very wild OCI changes(on time with me, rarely on time with my brother driving it) and now i have been doing the maintenance with the slow and steady method as it was pretty wicked in there(no sludge I could see but not the cleanest engine on the planet).
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Originally Posted By: jrc2905
I bought a 1999 Nissan sentra with 120,000 miles. After owning the car for a while a noticed an engine knock on start up and when I am on the highway stepping and letting off the gas. I thought it was the timing chain so I took the valve cover off to look at it. What I found was that all non moving parts had a quarter inch of black hard crusty crud on it. It looks like it was a sludge problem at some point. I tried an engine cleaning treatment with no results. I am thinking the engine needs to be rebuilt but it passed emission testing no problem. Could it be the oil pump gone bad, any ideas?
Find a good low mileage used engine asap. Been a tech on them for a long time. If you're hearing a knock and it's sludged cut your losses now. Those engines are plentiful used and a low-mileage unit will run you about $500-650. It was not seviced at all to sludge like that. Those engines do not have sludging issues unless they are ignored. The reason it knocks worse at startup is because the rods&mains are worn and the lack of oil pressue leaves way too much clearance between the crank&bearings. Once the pressue builds it fills in the excessive clearance somewhat and it quiets down. It will before long knock on startup and the lock tabs on the bearings will not be sufficient to hold the bearings in place any longer and then the little man with the hammer will begin to find his way out the side of your engine block. There's nothing in a bottle going to fix her now. It's going to take those green leafy things in your back pocket(and alot of them)to fix her right now. I wish I had her at my shop. I want to go to Mexico for a month.
I bought a 1999 Nissan sentra with 120,000 miles. After owning the car for a while a noticed an engine knock on start up and when I am on the highway stepping and letting off the gas. I thought it was the timing chain so I took the valve cover off to look at it. What I found was that all non moving parts had a quarter inch of black hard crusty crud on it. It looks like it was a sludge problem at some point. I tried an engine cleaning treatment with no results. I am thinking the engine needs to be rebuilt but it passed emission testing no problem. Could it be the oil pump gone bad, any ideas?
Find a good low mileage used engine asap. Been a tech on them for a long time. If you're hearing a knock and it's sludged cut your losses now. Those engines are plentiful used and a low-mileage unit will run you about $500-650. It was not seviced at all to sludge like that. Those engines do not have sludging issues unless they are ignored. The reason it knocks worse at startup is because the rods&mains are worn and the lack of oil pressue leaves way too much clearance between the crank&bearings. Once the pressue builds it fills in the excessive clearance somewhat and it quiets down. It will before long knock on startup and the lock tabs on the bearings will not be sufficient to hold the bearings in place any longer and then the little man with the hammer will begin to find his way out the side of your engine block. There's nothing in a bottle going to fix her now. It's going to take those green leafy things in your back pocket(and alot of them)to fix her right now. I wish I had her at my shop. I want to go to Mexico for a month.
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