WahooSteeler Posted October 4, 2018 Share Posted October 4, 2018 My truck has always had a small drip since I got it several years ago but it was not much of a concern since I only used it for weekend trash runs, yard work, when it snowed, and an occasional trip out to a friend's hunting camp. I typically drove it only @3k miles a year. Fast forward to now and it is essentially my son's daily driver for at least the next couple of years until I give him my car and get a new DD for myself. With daily use and occasional highway trips of at least 30+ miles, I want to eliminate the oil leak(s). On the highway, with more leakage due to high rpms and hot thinned out oil hitting the exhaust pipe, it looks like I'm driving a crop-duster with the amount of smoke billowing from under the truck. Embarrassing to say the least LOL. So, one by one recently I have had the following done: 1) valve cover gasket, 2) oil filter adapter with new O-rings, 3) rear main seal. I can't say I was surprised the leak continued after the new valve cover gasket or even the oil filter adapter. Even though I am only the second owner, I assumed the rear main seal had never been done and was the likely cause, being a Jeep of course. I was a bit disheartened when I picked it up today from the RMS being replaced and the leak remains. The owner of the shop that did the work was off today, so I did not have a chance to talk to him about it. I have known him a long time and trust what he says. The tech that worked on it drives a 93 XJ. That does not guarantee he is an ace at working on Jeeps or if he's ever done a RMS, but based on the relationship I have with the owner I trust he would not have put this guy on the job if he didn't know what he is doing and I know he's been a wrench for many years. So the question is where to look next? I have an idea what the replies will be saying, but I'm hoping it's not "that" (trying not to jinx myself by avoiding saying anything specific LOL) and that my education continues with other possible causes that are easier and less expensive repairs than "that". My plans have always been to keep the truck for a looong time, so I have put a lot of money in to it the past year to make it a reliable and a safe DD for my son. But it's starting to wear me down, or I should say, wear out my wallet! Unfortunately I don't have the time, proper tools or necessary skills to do hard-core wrenching like a RMS, so repairs like that are an expensive and direct hit to my bank account! Link to comment Share on other sites More sharing options...
kryptronic Posted October 4, 2018 Share Posted October 4, 2018 I had an oil leak on my 95 YJ for years until I broke the engine down for a semi-rebuild and realized the PO didn't install a gasket when replacing the distributor. I realized that a couple days after I replaced the RMS, which was probably just fine as the YJ only has 36K original miles on it. Could be anywhere - any surface that uses a gasket (head gasket, valve cover gasket, oil pan gasket, distributor gasket, dipstick, etc.). What side of the vehicle is the leak on? Is the oil only showing up on the lower half of the block? The back only? When re-gasketing, be sure to follow torque specs. For example, the valve cover bolts require 55 in/lbs of torque and I've found on some Jeeps them torqued down to 15-20 ft/lbs causing leaks. Something may be torqued to the wrong spec causing issues. Have you cleaned the engine to remove all the grit/grime/grease to more easily trace the leak? When I get a new Jeep, the first thing I do is detail the engine so I can start seeing the problems. Remember that when oil leaks, when you're driving it will spray/spread from the top to the bottom and from the front to the back because of wind/motion. So look top->down and front->back to try and pinpoint the source. Good luck. Link to comment Share on other sites More sharing options...
WahooSteeler Posted October 5, 2018 Author Share Posted October 5, 2018 Krypto, it hits the ground about dead center at the back of the block. Understood on running downhill, hence why I started with the valve cover and moved my way down oil filter adapter and then RMS. Just had a new oil pan gasket put on with the RMS job. Link to comment Share on other sites More sharing options...
kryptronic Posted October 5, 2018 Share Posted October 5, 2018 2 hours ago, WahooSteeler said: Krypto, it hits the ground about dead center at the back of the block. Understood on running downhill, hence why I started with the valve cover and moved my way down oil filter adapter and then RMS. Just had a new oil pan gasket put on with the RMS job. The drips always show up on the driveway at the back of the engine. Look from the top down and from the front to the back. What has oil on it? Find what does and what doesn't, and inbetween is your problem. You can probably rule out the gaskets and seals you've already changed, so how does that distributor gasket look? Link to comment Share on other sites More sharing options...
WahooSteeler Posted October 5, 2018 Author Share Posted October 5, 2018 10 minutes ago, kryptronic said: The drips always show up on the driveway at the back of the engine. Look from the top down and from the front to the back. What has oil on it? Find what does and what doesn't, and inbetween is your problem. You can probably rule out the gaskets and seals you've already changed, so how does that distributor gasket look? Not trying to be a smartazz, but "What side of the vehicle is the leak on? Is the oil only showing up on the lower half of the block? The back only?", you asked so I answered. As I said in the OP, the truck has had a steady drip for years, it has 220k miles. This is not new, the entire block has a coating of oil and grease buildup from all these years. I have been hesitant to put any substantial water/soap or degreaser on the engine until I got some other things buttoned up, but that is a step I need to take now. Never thought of the distributor gasket, worth a look. My fear, of course, is the head gasket and that being another very labor intensive $$$ repair. Link to comment Share on other sites More sharing options...
kryptronic Posted October 5, 2018 Share Posted October 5, 2018 I'd recommend cleaning it off so you can see where it's coming from. Gently with degreaser, water and sponge. Mind the electrical connections. Everything in the engine compartment is designed to get wet. Once it's clean, the source of the leak should become quite clear. Link to comment Share on other sites More sharing options...
Dzimm Posted October 5, 2018 Share Posted October 5, 2018 1 hour ago, kryptronic said: I'd recommend cleaning it off so you can see where it's coming from. Gently with degreaser, water and sponge. Mind the electrical connections. Everything in the engine compartment is designed to get wet. Once it's clean, the source of the leak should become quite clear. Just like kryptronic says, watch the electronics the best you can from direct water spray and scrub the engine down good. I use Simple Green since its cheap and can safely be poured in your yard or driveway, and just put it in a squirt bottle or water bottle with a hole in the lid. Link to comment Share on other sites More sharing options...
WahooSteeler Posted October 5, 2018 Author Share Posted October 5, 2018 I don't have any of the symptoms of a blown head gasket, with the exception of lately I've had high temps on highway use or when I'm also running A/C. Normal stop and go w/out AC on temps are fine. But I digress. So if it's the dizzy gasket, that will be the most expensive dizzy gasket repair job ever.........when added together with my RMS replacement cost. But I'll still be happy the leak is fixed and I'm sure it was only a matter of time on the RMS. At least that's what I'm telling myself. Link to comment Share on other sites More sharing options...
Manche757 Posted October 5, 2018 Share Posted October 5, 2018 Wahoo you have done a lot. Are you sure you do not have transmission fluid leak? If it leaks onto some of the exhaust system, it can produce a crazy amount of smoke like there is a fire. Link to comment Share on other sites More sharing options...
Wounded_Fighter Posted October 5, 2018 Share Posted October 5, 2018 Valve cover PCV valves and oil Filler cap. The Filler cap leaks slightly at high rpm with a good gasket on mine, I mean... It's a TIGHT fit cap... have to push it on really good. Link to comment Share on other sites More sharing options...
cruiser54 Posted October 5, 2018 Share Posted October 5, 2018 Some of you guys have seen this numerous times. Some never. You don't need a mechanic to diagnose this. I’d be looking up ABOVE first, and VERIFYING the source of the oil leak YOURSELF. Everybody, who doesn’t own or have to pay for or perform your vehicle repairs, loves to poke their noggin UNDER the Jeep and come out bearing the false bad news that your RMS is leaking. Many mechanics, friends, and good old Uncle Bob seem to enjoy telling you it’s the rear main seal. Has a catastrophic ring to it, doesn’t it? A simple leak at the back of the valve cover or other source could produce the same symptoms. You don’t need to be a mechanic to figure this out. If you have good eyesight and a dim flashlight, you’re good to go on your own. Don’t jump on the RMS/oil pan gasket bandwagon right off the bat. Almost any oil leak on your 4.0 is gonna drip from the RMS area for two simple reasons: First off, the engine sits nose-up and any oil will run back to the RMS area. Secondly, the RMS area is also the lowest point on the engine. Simple physics and the old plumber’s adage apply here: “Crap flows downhill”. Valve cover gasket, oil pressure sending unit, oil filter adapter seals and distributor gasket, in that order, have to be eliminated as possibilities first. Revised 1-31-2016 Link to comment Share on other sites More sharing options...
mjeff87 Posted October 5, 2018 Share Posted October 5, 2018 ^^^great post Cruiser Leaks don't leak up, they leak down (that darned gravity thing LOL). Try to find the highest point you can that has oil on it and clean it off, see if it rewets itself. Better yet, as suggested, clean the whole engine (just watch the TPS and other assorted naughty electrical bits) and let it dry. Whatever is leaking should become obvious after that. How does the right side of your block look, especially where the head meets the block in the lifter galley area? That's a potential leak site, technically a head gasket issue but not lethal since there's no coolant or combustion pressure in that area. Link to comment Share on other sites More sharing options...
WahooSteeler Posted October 5, 2018 Author Share Posted October 5, 2018 52 minutes ago, mjeff87 said: ^^^great post Cruiser Leaks don't leak up, they leak down (that darned gravity thing LOL). Try to find the highest point you can that has oil on it and clean it off, see if it rewets itself. Better yet, as suggested, clean the whole engine (just watch the TPS and other assorted naughty electrical bits) and let it dry. Whatever is leaking should become obvious after that. How does the right side of your block look, especially where the head meets the block in the lifter galley area? That's a potential leak site, technically a head gasket issue but not lethal since there's no coolant or combustion pressure in that area. Jeff, followed Cruiser's logical advice of starting up high and working down when I started replacing gaskets and seals. Like I said above, I've been hesitant to clean the engine under the theory if oil is getting OUT somewhere, water and cleaners can get IN, but it's time to get it cleaned and just be patient with doing it carefully so I can identify the true source. My entire block has a couple millimeter thick coating of grease from all the years so it is probably hard to determine if that's the source. As of now my plan this weekend is to clean it the best I can and probably pro-actively replace the dizzy gasket since I can do that on my own. What about getting it steam cleaned to really get it good in all the tight and hard to reach areas? Link to comment Share on other sites More sharing options...
mjeff87 Posted October 5, 2018 Share Posted October 5, 2018 You have a local quarter-operated u-do-'em car wash way up there in the mountains?? I'd drive it there, soak the whole thing down with simple green and let it sit as long as you can without drawing attention to yourself, then blast it all off. Take a can of WD-40 in case you get the dizzy cap or wires too wet (happened to mine once.....once). Drive it home to dry it off, then you can do some finish/final cleaning with a rag and some brushes in your driveway. Link to comment Share on other sites More sharing options...
WahooSteeler Posted October 7, 2018 Author Share Posted October 7, 2018 Got at least a good layer of grease off the block today, valve cover and around the pan and bellhousing. Laid under the truck for a good while and then took this video that, I believe, confirms the source was and still is the RMS unless there is something else in that area I am unaware of. I observed the dizzy base and oil filter adapter for several minutes two or three different times while the truck remained idling for @30mins. Valve cover stayed clean and at least where I could see where the head meets the block I didn't see anything fresh. But I need to clean the rear of the block better and observe again just to be sure. I also observed a very very minor drip at the left front corner of the pan, not sure if the tech under or over tightened it when reinstalling from the RMS job. I could see where he did a good job of cleaning the bottom of the block and they used a Felpro gasket. But, it'll be going back this week to get the RMS redone! I had just wiped clean the bell-housing before I started the video. The drip from the RMS happens about every 30 seconds, but of course that's while sitting at idle. RMS_Leak_Oct_18.mp4 Link to comment Share on other sites More sharing options...
bluenotenick Posted October 7, 2018 Share Posted October 7, 2018 That "oil" looks watery, but the video was tough to stream...Not yet sold on the RMS. More cleaning in this area. Link to comment Share on other sites More sharing options...
WahooSteeler Posted October 7, 2018 Author Share Posted October 7, 2018 19 minutes ago, bluenotenick said: That "oil" looks watery, but the video was tough to stream...Not yet sold on the RMS. More cleaning in this area. You can literally see a drip come from the crank. The oil is brand new, like 10 miles on it, hence the lighter color IMO. Link to comment Share on other sites More sharing options...
MJCARENA Posted October 7, 2018 Share Posted October 7, 2018 Maybe the mechanic put the seal in facing the wrong way. Easy to do if you don't pay attention. Link to comment Share on other sites More sharing options...
bluenotenick Posted October 7, 2018 Share Posted October 7, 2018 1 hour ago, WahooSteeler said: You can literally see a drip come from the crank. The oil is brand new, like 10 miles on it, hence the lighter color IMO. Yeah you're right... on a second look it is fresh oil mixed with outside dirt. But there are still other things that resolve their drip at this spot. The back of my valve cover dripped all the way down to this same spot. Link to comment Share on other sites More sharing options...
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