Smoke at start up, valve guides or piston rings?
02-05-2011, 06:48 AM
#31
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Year: 1996 two-door SE
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Engine: 4.0
I was able to get the valve cover pulled today. What a mess. Gunk between the valves going almost to the top of the pushrods, especially around #5, #6 and #1. I expected it to be a bit dirty due to the mileage but this is ridiculous. I had even run seafoam through the crankcase, into the vacuum lines and through the tank and it is still disgusting.
I don't get why people don't take better care of their vehicles.
I don't get why people don't take better care of their vehicles.
It's possible that the oil return passages may be partially clogged from the sludge. Excess oil sitting on top of the cylinder head could be finding its way down the valve guides into the combustion chambers. I'd manually clean away the sludge up there as best as you can. We used to use a straightened metal coat hanger to open up oil return passages on the old Chevy V8s. I wouldn't recommend using chemical solvents in an attempt to clean the sludge from the engine. Dispersed sludge can clog your oil pick-up tube screen.
02-05-2011, 04:18 PM
#32
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No updates because nothing new to report. I don't have the money for the seals and gaskets I need to do the work, oh and the CCV hose that got broken when I took off the valve cover too. 
I should have all the parts next week though, so hopefully I will have everything fixed soon.
Anyway, I'm pretty sure what you're saying regarding the valve guides is occurring. It is only happening in #6 and only from one side of the plug, which indicates only one valve is leaking oil down into the cylinder. I'm going to replace the valve seals and valve cover gasket. I'm 99% sure the small amount of oil I was finding under the tranny pan was coming from the back of the valve cover. Since I've removed it the oil has stopped dripping onto the ground.
That's good news, as I really didn't feel like replacing the RMS anytime soon.
I did get some pictures of the mess inside so lemme get those posted. Also got a pic of the hose I broke, I want to make sure I buy the correct replacement so I'll post a couple pics of that too.
I was going to clear out as much of the crud as I could by hand, and then use some brake cleaner to get whatever is left. Now I'm paranoid about blocking my oil pick-up screen. What would be the best way to clean this up?
Thanks!
I should have all the parts next week though, so hopefully I will have everything fixed soon.Anyway, I'm pretty sure what you're saying regarding the valve guides is occurring. It is only happening in #6 and only from one side of the plug, which indicates only one valve is leaking oil down into the cylinder. I'm going to replace the valve seals and valve cover gasket. I'm 99% sure the small amount of oil I was finding under the tranny pan was coming from the back of the valve cover. Since I've removed it the oil has stopped dripping onto the ground.
That's good news, as I really didn't feel like replacing the RMS anytime soon.I did get some pictures of the mess inside so lemme get those posted. Also got a pic of the hose I broke, I want to make sure I buy the correct replacement so I'll post a couple pics of that too.
I was going to clear out as much of the crud as I could by hand, and then use some brake cleaner to get whatever is left. Now I'm paranoid about blocking my oil pick-up screen. What would be the best way to clean this up?
Thanks!
Sorry for this late response. Can you update us on your work to cure your oil consumption problem?
It's possible that the oil return passages may be partially clogged from the sludge. Excess oil sitting on top of the cylinder head could be finding its way down the valve guides into the combustion chambers. I'd manually clean away the sludge up there as best as you can. We used to use a straightened metal coat hanger to open up oil return passages on the old Chevy V8s. I wouldn't recommend using chemical solvents in an attempt to clean the sludge from the engine. Dispersed sludge can clog your oil pick-up tube screen.
It's possible that the oil return passages may be partially clogged from the sludge. Excess oil sitting on top of the cylinder head could be finding its way down the valve guides into the combustion chambers. I'd manually clean away the sludge up there as best as you can. We used to use a straightened metal coat hanger to open up oil return passages on the old Chevy V8s. I wouldn't recommend using chemical solvents in an attempt to clean the sludge from the engine. Dispersed sludge can clog your oil pick-up tube screen.
Last edited by Superhero; 02-05-2011 at 04:26 PM.
02-05-2011, 04:20 PM
#34
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Year: 1992
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The last one is the engine build date code. I've tried looking it up but haven't been able to decipher it. The one site I found with an explanation of the code doesn't seem to apply to the tag on my engine.
02-06-2011, 07:11 AM
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Year: 1996 two-door SE
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I must confess that it's been 25 years since I worked as an automobile technician and photographs may be deceiving; however, in my opinion, neither the spark plug fouling nor the sludge formation appears severe. Most often, oil fouled plugs are black and oily. Your rocker arms and springs look fairly clean. I do see in the photographs a little sludge on the cylinder head itself, but I've seen problem accumulation that looked like a layer of black mud coating every part and causing a pint or more of liquid oil to pool on top of the head because of clogged return passages.
Having said that, valve stem seals may still be warranted, but there's one question that everyone failed to ask. What color is the smoke when you first start the engine? White, blue-gray, or black?
As far as cleaning is concerned, I'd leave the sludge alone, and you don't have to worry about a clogged pick up screen with that little of accumulation.
Having said that, valve stem seals may still be warranted, but there's one question that everyone failed to ask. What color is the smoke when you first start the engine? White, blue-gray, or black?
As far as cleaning is concerned, I'd leave the sludge alone, and you don't have to worry about a clogged pick up screen with that little of accumulation.
Last edited by 96tudor; 02-06-2011 at 08:18 AM.
02-06-2011, 02:24 PM
#36
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Well, I've never worked as an automobile tech at all, so you've got me trumped there. I only thought mine was extra dirty because none of the engines I've pulled apart, even with the same miles, has even been half as bad. Admittedly, my experience is limited to a handful of engines, so I could easily have an inaccurate idea of what a dirty engine really is. I'll go with your experience and be glad my engine is not as disgusting as I thought. 
I did clean the fouled plug a bit before I posted that pic. It was quite a bit worse than it looks. It was also mostly just fouled on the one side. If I knew which valve that side was under I'd know which valve seal is leaking. Since I don't, and since I've got the top off anyway, I might as well just replace all the seals.
As far as the sludge goes, I'll just wipe things out with a rag and call it a day then.
The smoke is mostly white, maybe a little bit blue-gray. It definitely wasn't black. I don't think the head gasket is leaking. My oil doesn't have any water or coolant in it that I can see, and the coolant is still full, so I don't think that's going anywhere.
That leak coming from somewhere around the back of the engine has returned. Poop! I was hoping it was just the valve cover gasket since it was rotting away but apparently it is not. It's so weird how my Jeep just starts and stops leaking at what seems like random times. Time to clean up around the RMS and see if that's where it is coming from. I gotta replace the oil pan eventually so it won't be such a big deal if I gotta do the RMS. It'll give me a chance to really check out the lower part of my engine and see what shape it's in anyway.
Thanks for your observations and advice.
I did clean the fouled plug a bit before I posted that pic. It was quite a bit worse than it looks. It was also mostly just fouled on the one side. If I knew which valve that side was under I'd know which valve seal is leaking. Since I don't, and since I've got the top off anyway, I might as well just replace all the seals.
As far as the sludge goes, I'll just wipe things out with a rag and call it a day then.
The smoke is mostly white, maybe a little bit blue-gray. It definitely wasn't black. I don't think the head gasket is leaking. My oil doesn't have any water or coolant in it that I can see, and the coolant is still full, so I don't think that's going anywhere.
That leak coming from somewhere around the back of the engine has returned. Poop! I was hoping it was just the valve cover gasket since it was rotting away but apparently it is not. It's so weird how my Jeep just starts and stops leaking at what seems like random times. Time to clean up around the RMS and see if that's where it is coming from. I gotta replace the oil pan eventually so it won't be such a big deal if I gotta do the RMS. It'll give me a chance to really check out the lower part of my engine and see what shape it's in anyway.
Thanks for your observations and advice.
I must confess that it's been 25 years since I worked as an automobile technician and photographs may be deceiving; however, in my opinion, neither the spark plug fouling nor the sludge formation appears severe. Most often, oil fouled plugs are black and oily. Your rocker arms and springs look fairly clean. I do see in the photographs a little sludge on the cylinder head itself, but I've seen problem accumulation that looked like a layer of black mud coating every part and causing a pint or more of liquid oil to pool on top of the head because of clogged return passages.
Having said that, valve stem seals may still be warranted, but there's one question that everyone failed to ask. What color is the smoke when you first start the engine? White, blue-gray, or black?
As far as cleaning is concerned, I'd leave the sludge alone, and you don't have to worry about a clogged pick up screen with that little of accumulation.
Having said that, valve stem seals may still be warranted, but there's one question that everyone failed to ask. What color is the smoke when you first start the engine? White, blue-gray, or black?
As far as cleaning is concerned, I'd leave the sludge alone, and you don't have to worry about a clogged pick up screen with that little of accumulation.
02-07-2011, 08:55 AM
#37
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I just hope nothing that I've written has led you astray. As you have already mentioned, white smoke can indicate coolant (for example, head gasket or a crack), blue can indicate oil (e.g., valve stem seals or oil control rings), and black can indicate fuel (e.g., leaking injector). Good luck, and keep us informed.
02-07-2011, 05:15 PM
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02-07-2011, 08:29 PM
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I must confess that it's been 25 years since I worked as an automobile technician and photographs may be deceiving; however, in my opinion, neither the spark plug fouling nor the sludge formation appears severe. Most often, oil fouled plugs are black and oily. Your rocker arms and springs look fairly clean. I do see in the photographs a little sludge on the cylinder head itself, but I've seen problem accumulation that looked like a layer of black mud coating every part and causing a pint or more of liquid oil to pool on top of the head because of clogged return passages.
Having said that, valve stem seals may still be warranted, but there's one question that everyone failed to ask. What color is the smoke when you first start the engine? White, blue-gray, or black?
As far as cleaning is concerned, I'd leave the sludge alone, and you don't have to worry about a clogged pick up screen with that little of accumulation.
Having said that, valve stem seals may still be warranted, but there's one question that everyone failed to ask. What color is the smoke when you first start the engine? White, blue-gray, or black?
As far as cleaning is concerned, I'd leave the sludge alone, and you don't have to worry about a clogged pick up screen with that little of accumulation.
02-08-2011, 06:27 PM
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I started pulling rocker arms today and I couldn't get a single valve spring retainer to come off. At all. Any ideas here? Also, a part of my cooling system broke when I tried to move a hose. Old, brittle plastic sucks, especially when it throws coolant all over the place. On top of all this it is extremely windy today so various bits kept getting blown into my engine. It also managed to blow chunks of carbon built up between the valve springs down into the pushrod tubes. Argh. I decided to call it a day before things got more frustrating.
I was also surprised to find a bit of metal floating around in there. Take a look at the pic. Can you guess what it is? Now I know why #6 is leaking oil into the cylinder from the top - the metal is a piece of what was the valve seal for what I'm pretty sure is the exhaust valve on #6 (not sure though, haven't pulled the rocker arms or anything that far back yet). I gotta find the rest of it if it isn't still attached to the seal. I also gotta figure out what could have destroyed the seal so badly in the first place before I put everything back together or all this work is a waste of time.
On a good note - so far all the pushrods I have pulled are showing very little wear (look virtually brand new except for the coat of sludge) and are all in fantastic shape. Same goes for the fulcrums, and there is normal/light wear where the rocker arms rub the top of the valve stem (tappet? I don't remember what it is called). The springs also feel good. Hopefully all the valve guides are solid too.
Interestingly, I think I figured out some unsolved dents in the Jeep. When I got it the doors had been beaten up pretty badly. The rest of the body is in great shape, but the doors are bad. I am pretty sure a woman owned the Jeep because there is a hole in the carpet where a high heel would go when driving (just under gas pedal). My wife has worn the exact same hole from heels in several vehicles. To test this she put some heels on, sat in the driver's seat and confirmed that indeed the hole (and the subsequent minor rust where the hole is, from the heel also wearing the paint off, which I sanded and sprayed some primer over to prevent rust) was caused by high heels. Also, covering the hole, probably to prevent further damage to the actual metal, was a Smirnoff Ice, Watermelon bottle cap. My wife's heel rested on top of it perfectly. I think it is more likely a woman's type of drink than a mans. Also, I found on one of the doors where someone had scratched in "suck my dick *****", and all the dents look like someone kicked the doors. In fact, all the dents are only where someone could easily kick. So I figure a pissed off boyfriend beat the **** out of the doors on the Jeep. Of course, all this could be totally wrong, but I feel pretty comfortable with my Sherlock Holmes style conclusion.
Well, looks like I'll need to replace most of the coolant lines and fittings. I suspect as I try to fix the broken part other pieces are going to snap. Might as well do it all. If I had the money I'd pull the whole engine and stroke it and replace everything under the hood too. I know lots of people have the "if it ain't broke don't fix it" approach, but forget that. I belong more to the school of "if one part is breaking that means other parts probably will too - let's just replace everything with brand new stuff and avoid a bunch of headaches and work down the road". Of course, this school of thought also requires a fair amount of money on hand...
I was also surprised to find a bit of metal floating around in there. Take a look at the pic. Can you guess what it is? Now I know why #6 is leaking oil into the cylinder from the top - the metal is a piece of what was the valve seal for what I'm pretty sure is the exhaust valve on #6 (not sure though, haven't pulled the rocker arms or anything that far back yet). I gotta find the rest of it if it isn't still attached to the seal. I also gotta figure out what could have destroyed the seal so badly in the first place before I put everything back together or all this work is a waste of time.
On a good note - so far all the pushrods I have pulled are showing very little wear (look virtually brand new except for the coat of sludge) and are all in fantastic shape. Same goes for the fulcrums, and there is normal/light wear where the rocker arms rub the top of the valve stem (tappet? I don't remember what it is called). The springs also feel good. Hopefully all the valve guides are solid too.
Interestingly, I think I figured out some unsolved dents in the Jeep. When I got it the doors had been beaten up pretty badly. The rest of the body is in great shape, but the doors are bad. I am pretty sure a woman owned the Jeep because there is a hole in the carpet where a high heel would go when driving (just under gas pedal). My wife has worn the exact same hole from heels in several vehicles. To test this she put some heels on, sat in the driver's seat and confirmed that indeed the hole (and the subsequent minor rust where the hole is, from the heel also wearing the paint off, which I sanded and sprayed some primer over to prevent rust) was caused by high heels. Also, covering the hole, probably to prevent further damage to the actual metal, was a Smirnoff Ice, Watermelon bottle cap. My wife's heel rested on top of it perfectly. I think it is more likely a woman's type of drink than a mans. Also, I found on one of the doors where someone had scratched in "suck my dick *****", and all the dents look like someone kicked the doors. In fact, all the dents are only where someone could easily kick. So I figure a pissed off boyfriend beat the **** out of the doors on the Jeep. Of course, all this could be totally wrong, but I feel pretty comfortable with my Sherlock Holmes style conclusion.
Well, looks like I'll need to replace most of the coolant lines and fittings. I suspect as I try to fix the broken part other pieces are going to snap. Might as well do it all. If I had the money I'd pull the whole engine and stroke it and replace everything under the hood too. I know lots of people have the "if it ain't broke don't fix it" approach, but forget that. I belong more to the school of "if one part is breaking that means other parts probably will too - let's just replace everything with brand new stuff and avoid a bunch of headaches and work down the road". Of course, this school of thought also requires a fair amount of money on hand...
Last edited by Superhero; 02-08-2011 at 06:31 PM.
02-08-2011, 06:29 PM
#43
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Here are the pics. The first two are of the broken piece of metal that goes around valve stem seals. I haven't actually gotten to the broken seal yet, but I'm hoping the remaining bits of metal are still attached so I don't have to try to find them before they get into a bearing or something. The last is the broken coolant thingie.
02-08-2011, 06:37 PM
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Here are the pics. The first two are of the broken piece of metal that goes around valve stem seals. I haven't actually gotten to the broken seal yet, but I'm hoping the remaining bits of metal are still attached so I don't have to try to find them before they get into a bearing or something. The last is the broken coolant thingie.
02-08-2011, 06:47 PM
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Nope, that metal is part of a band that goes around the valve seal. It helps the rubber to keep its shape. Gimme a sec I'll post a pic of a new one. Somehow that piece of metal snapped, and I really hope I can figure out why. I don't think some burrs on the valve stem would have caused that kind of failure.
Heater control valve smeater control valve! Thanks! Maybe it was ready to go. That might explain why my heater has been lacking a little bit lately... Now to buy a replacement.
Heater control valve smeater control valve! Thanks!
Maybe it was ready to go. That might explain why my heater has been lacking a little bit lately... Now to buy a replacement.