Ok gents. Heres my issues.
I hear the ticking, especially when it the motor is cold.
4.0, 148,000 miles.
Cold oil pressure- 60-80
after it warms up- 20 idle, 30-40 hgwy speeds, sometimes drops to slightly below 20 at idle when warm
Temp- rarely ever reaches 210, only on the warmest days on the interstate, usually stays at the notch between 100-210 (150?) as soon as I get off the interstate, drops down to this notch.
Was blowing white smoke after idling at red lights for extended periods, none while driving or accelerating, only when taking off after idling, and then only when warmed up to the "normal" temperature that she likes to run at.
ticking is still there, but barely noticable once warmed up..
I know its alot of issues, I think they are probably interconnected, but Id like to hear your opinions.
motors gettin warn. that ticking is a valve malfunctioning. Find what cylinder it is and see if it is replaceable or not. Also with the white smoke your getting blowby and firing oil in a cylinder. Pull the plugs and see which has oil residue on it. If that plug is the same that has the bad valve you may get a cheap and easy fix.
Check your oil to see if you got some chocolate milk in there from water mixing with the oil. You should be able to see it on the dipstick. If you are unsure after looking there then do an oil change. White smoke is usually water. Water means blown head gasket or cracked head. That can definitely affect oil pressure.
Normally if you have a head gasket leak you will have bubbles in the coolant when running and high temps not cool temps, but not always. Your oil pressure is not that bad? Are you for sure the gauge is even correct(on coolant temp and oil pressure) The gauges on a YJ were the most unreliable part of the system. I had to do some sensor replacement, ground wire cleaning, and instrament panel trace cleaning to get my to work properly. Hook up a mechanical gauge to check oil pressure(its not that far out though) and use a IR thermometer to check the temp of the block temp(it should be a little lower than actual water temp)
If you actually have low temps then the most likely culprit is your thermostat. It is stuck/rusted open. If you haven't changed your coolant in the last 300000 miles then it a good time to replace the thermostat, flush the block and change the coolant. Low operating temps or short trips will produce the white smoke(water vapor) as the moisture in the air going through the engine is not super heated to a fine/invisible steam but a low temp/thick visible steam. Check for a head gasket though as listed above and also smell the exhaust, it shouldn't smell sweet, if it does it has antifreeze in it.
As far as the ticking? I thought all AMC designed/based engines tick?
i know my 2.5 ticks when i first start it until it warms up but that because it has a leaking manifold gasket. not sure if that could be the ticking your hearing on the 4.0 or not but i know i have heard it on alot of different engines and sounds the same.
Well It does have a semi sweet smell to it, but when I check the oil, there is no water in it (I thought head gasket first) and when I check the water, the coolant level in the overflow bottle never seems to move. I pulled the dipstick on it, but havent seen the chocolate milk effect yet, but the A/f i put in the resoivoir a couple weeks ago does have a brown tint to it... Hmmm. Time for a head rebuild/gasket job and engine flush me thinks??? Might as well swap out the lifters with some new ones while Im at it. That might also explain where my oil is going hahaha...
I think your making mountains out of molehills at this point. Feel around your manifold gasket and feel for leaks. Fix them if so. Some had gaskets, some didn't, use a felpro gasket either way. Also look for missing/broken manifold bolts or even a cracked manifold.
Flush the block, change the coolant, and change the thermostat, easy jobs. Brown coolant probably means that the coolants anti corrosion properties are exhausted and your block is rusting. Rusting causes the thermostat to stick open. Stuck thermostats causes low temps and low temps can cause the white smoke.
Start simple, don't go tearing into the head just yet.
As far as using oil, bad lifters won't cause that. Jeeps are notorious for leaking around the valve cover. Is yours? I may look like a little, but it can be a significant amount. Other causes can be a bad rear seal, worn rings, or worn valve guides, but not bad lifters.
Also a good way to free a stuck lifter is to run a quart of ATF in the engine for several hundred miles before you change the oil. ATF is 30 weight oil with lots of detergents to clean things out.
Ill flush the coolant when I get back. Im out to sea for a bit. Ill take the time and dump some atf in the engine as well, and swap the T-stat for a new one. It would be nice if this fixed the issues. I know the valve cover gasket needs changing, as the oil gremlin likes to take a oil crap on the side of my block quite often. Anyone know what size the o-ring on the dipstick tube is? Its always leaking a bit as well. The only thing Im actually truly worried about is the P.O. didnt do oil changes often, and I found a small amount of metal particles in the oil.