blowin oil

[unclebird]

:confused: 4.2 blowin oil out of pcv gromet. 129k miles. No real changes yet, other than mc2100. @ start I have pressure, then after temp. goes up pressure drops to 0 psi. I'm guessing oil is going up,and not coming down until it sits long enough. I've had the valve cover off twice, and didnt see anything obvious. Why isn't it coming out of the other end of the valve cover into breather?

[Doc Holiday13]

Actually its your CCV and you are getting blowby(I think thats the name of it), but basically you have a degraded oil seal on one or more of your pistons. SO you basically need an engine rebuild to fix the problem

[unclebird]

thx doc, not the answer i wanted to hear though, oh well. Would a compression check verify that? It just started doing it recently, real bad.

[Doc Holiday13]

Normally I would say yes, but don't waste your money on a comp. test. Ask any competent mechanic and he'll probably tell you the same thing. Especially since you said you already pulled the valve cover and it wasn't crazy clogged with sludge.

Sounds like its time for engine swap!!! :laughing: :grinpimp:

[unclebird]

why do i have pressure at start and then lose it after warm up? Why isnt it blowing out into my breather? You are probably right, i just dont want to believe it! hoping for a cheaper answer! Ill start hunting for another pwr. plant i guess. Think about it and tell me if you come up with something else. thx again.

[Fozzy_Bear]

Normally I would say yes, but don't waste your money on a comp. test. Ask any competent mechanic
...
Sounds like its time for engine swap!!! :laughing: :grinpimp:

Yeah, 0 oil pressure = excuse for more cubes :D

[Robert]

why do i have pressure at start and then lose it after warm up? Why isnt it blowing out into my breather? You are probably right, i just dont want to believe it! hoping for a cheaper answer! Ill start hunting for another pwr. plant i guess. Think about it and tell me if you come up with something else. thx again.


You have pressure at start up because the engine and the oil are cold. This makes the oil thicker and more resistant to flow. When the engine parts warm up, they expand, opening up the oil clearences at the bearings.

With your engine warmed up the oil flows easier, and can not fill the excessively worn bearings.
When my 4.2L went out, it also lost oil pressure. I swapped in a new set of bearings on the crank shaft and new oil pump. No good, still no pressure. I pulled it out, tore it apart for a full rebuild. Found the camshaft bearings just wasted.

[unclebird]

if i decide to rebuild what do i need to up grade while its out? daily driver, i keep hearing about the 4.0 head swap,hei and mc2100... what else? might as well do it right. i'm like e-body else i want pwr, gas mileage, and inexpensive. new short block?

[Doc Holiday13]

If you don't want to go too extreme just find a 4.0 HO to drop in istead of rebuilding. IF you want power drop a 5.0 from a mustang. Diesel swaps are pretty sweet too!!

[unclebird]

how tough to go 4.0 HO? is that fuel inj.? tons o wires? tranny mount ups? motor mounts? I was htinking 4.2 just for ease. With hei,2100 and 4.0 head thats close to 200hp isnt it? And almost 20 mpg from what I ve read here. I m just more fam. with carbs., scared of change! ME BRAD ME LIKE JEEP

[rockwells]

Ford 5.0's are cheap and everywhere. i got a 289 out of a junkyard for 250 bucks, and got a np435 tranny and a np205 t-case for 200 bucks. i bought a heavy duty 6 cyl radiator and shortened the rear driveshaft. all for under a grand. i can smoke my 42 inch swampers.

[Robert]

The 4.0L swap is not hard. It will bolt up to your existing transmission and frame mounts. Yes it is fuel injected. The wiring is not too difficult. Have to wire up a fuel pump, and splice into the power wires from the key switch. Little more than that, but it is more intimidating than actually doing it.
Doing a 5.0L swap would require a new bellhousing (possibly new tranny), engine mounts, exhaust, etc.. The wiring is really not much different than the 4.0L swap.

I would highly recommend doing one of these swaps instead of rebuilding your 4.2L, but that depends on your budget, time frame and desires.

[unclebird]

Ask any chick I've ever dated, well maybe not,dated, I like cheap and easy! I will probably stay with the 4.2, keep my mc 2100, go with the tfi or hei and the 4.0 head and then start tackleing some of the other things on the to do list. I loved the acronym I saw on here the other day JEEP, Just empty every pocket. How true, how true!

[geberhard]

K, do a search for blowbly before starting to get in the get a new engine bandwagon. The 4.2 Is a decent engine, even though not the best. There is something you can try adding to your oil that can minimize blowby. I am trying to remember the name, you can buy from any pasrt store, and someone posted the info here on how to do it. It will work somewhat, and get you by if what you are looking for is a cheap and easy solution. I say it is worth a shot before tearing stuff down. I had some blowby and it almost went away after I cleaned up the sludge and did the trick.

I will try searching but look around, it is a common trick. darn, what is the name of the fluid to add to the oil?

Darn!

[Go_Vols]

Ford 5.0's are cheap and everywhere. i got a 289 out of a junkyard for 250 bucks, and got a np435 tranny and a np205 t-case for 200 bucks. i bought a heavy duty 6 cyl radiator and shortened the rear driveshaft. all for under a grand. i can smoke my 42 inch swampers.

Need pics of this :flipoff2:

[unclebird]

This is my 5th CJ,3rd with a 258. they all leak oil. Usually from v-cover or rear main. I did flush the motor with kero. I wonder if that freed up some sludge? What is the cycle of oil through the motor? Where can I look for cloggs? Whats the best way to free them up and flush them out woth out just moving it and creating a time bomb? Im just not convinced its blow by yet. Its hard to type with your fingers crossed!!! I m still hoping for an easy fix. Do you think the oil additive will solve the drop in oil press?

[Robert]

This is my 5th CJ,3rd with a 258. they all leak oil. Usually from v-cover or rear main. I did flush the motor with kero. I wonder if that freed up some sludge? What is the cycle of oil through the motor? Where can I look for cloggs? Whats the best way to free them up and flush them out woth out just moving it and creating a time bomb? Im just not convinced its blow by yet. Its hard to type with your fingers crossed!!! I m still hoping for an easy fix. Do you think the oil additive will solve the drop in oil press?

Oil additive is not going to put metal back on the bearings. Neither is using a heavier oil. Worn bearings and/or oil pump are going to be you main reasons for low oil pressure.
On every 258 I have ever owned or worked on, the oil pressure sensor is mounted on the main oil galley, just behind the distributor. Oil comes out of the pump, through the filter, and into the main oil galley. If you have sludge that is so bad that the main oil galley is clogged, ITS TIME FOR REBUILD.

[unclebird]

:nuke: :mad3: Sounds like the tribe has voted my old motor off the island. I've never had a jeep with a v-8,hard top,manual combo,all my v-8's were autos, some rag tops,some hard tops never that combo. After listening to everyone on this site, I dont htink I want a v-8.Not enough HP gain in a 304,more effort than I want to put into a 350 or 302. Sounds like the 4.2 done right or the 4.0 gets the votes. Out of curiosity, has anyone done a 3.8 turbo GN motor or something along those lines, if so I'd love to hear about it!!!

[geberhard]

If you are doing a fuel injection swap, go Mustang or GM vortec. If you want the cheapest approach and bolt on, replace the 4.2 with another 4.2 :) It still is a sucky engine compared to most, even if you add a fuel injected kit. Ah, I think the name of the thing to add is "Alemite" or something like that. No, it will not cure all things, but may help and at $5 is a cheap try compared to an engine swap ;)

Gui

[unclebird]

I want it right...and cheap! I know an add. will not FIX it, I m just cant decide which way to go. I m swaying towards fresh 4.2 :nuke:

[geberhard]

fresh 4.2 expect to pay at least a grand :) rebuild will cost at least that much. I would recommend upgrading while you are at it :) Go fuel injection, you will be happy :)

[unclebird]

Pics of what?

[CJ-Jeeper]

Pics of what?

I would guess he's talking to the guy he quoted- smoking 42's with a junkyard 289

[meangreen]

I had the same problem with mine, when I tore the engine down I found a nice hole in two of my pistons, I just scraped that engine and bought a junkyard special and bolted it in. So far the best $100 I've spent on my jeep. 50,000 and still going!

[unclebird]

:fj: How fast to do a 4.2-4.2 swap? Just how gooda mekanik 'er ya boy?

[Chato]

I had a 1976 CJ5 with a 232 which is basically the same engine you have. When I started getting blowby I put a new PCV valve on it. You can get these at any parts store and it doesn't even have to be for a Jeep. I think mine was supposed to be for a GM something or other. After that it started fouling the spark plugs so I changed to Campion N 21 plugs and continued using it for 2 more years before it started losing power. These are cheap fixes and if they don't work then you fix it.

[unclebird]

:shaking: :( Why would plugs change any thing?? The pcv or ccv still rattles and pulls hard at idle, thats why I dont understand the oil blowing by that grommet. Why isn't it blowing into the breather? That should be a path of least resistance if the pcv valve were malfunctioning at hwy speeds or under torque? I'm still not convinced the problem is rings or cam bearings. Maybe its just wishful thinking on my part. Could i tbe a timing issue? I set the timing by ear/feel when I put on the mc2100. Knocked a little under load, so I ret. it till it did'nt do that. I'm getting 15 mpg+.Where do I look to see the oil return from the valve springs (valve cover off). I still think that may be the problem after I flushed it w/ kero? :confused: :nuke:

[Drifter]

I've gotta resurect this thread ....

I've got a mystery that sounds similar to your issue. I left my 258 happily idling unattended for probably 30mins (I got distracted). When I returned it was still idling along just like normal, but the ground was covered with oil, and 0 oil pressure. I just it off. Looked around, checked oil pressure guage line, checked oil filter. The top of the engine and firewall were covered with oil. The PCV was about 1/4 of the way out of the hole and covered with oil also. So ... put 3 quarts of oil :confused: back in the motor and fired it up. 70psi pressure cold, 30 psi warm, no knock, or rattles, runs perfect and no oil coming out anywhere :shaking: Pulled the PCV, no blow by, lots of vacuum. PCV hooked up, good vacuum through the breather. I'm completely stumped. The head was decked, ported and polished less than 1,000 miles ago. New high vol. oil pump was installed at the same time. My excavator's theory had something to do with it being cold (15 deg.) out, and moisture stopping the PCV, but that didn't make a whole lot of sense. I've spent alot of time around engines and never seen anything like this. I hope I don't have to wait for it to do it againg to find out what the issue is. Any ideas would be appreciated.

Thanks,

Don

[HybridPOS]

You have a new PCV? Is it stuck? You have it going the correct way?

[Rattlecan]

pull the valve cover off and check for sludge. Has your rig been sitting for a while?

Same problem with my 258. Had build up that I couldn't see. Pulled the valve cover off - brought it to a buddy's shop - stuck it in the dip tank and sludge began to seep out... After I stuck the VC back on it has been fine.

I don't care what anyone else here says - Check cylinder compression. It is worth the $$$ to head a potential domino effect off early. Collapsed ring can be fixed easier than a scored cylinder wall because you kept driving it.