Front aftermarket bumper opinions

[Pete M]

51 minutes ago, Bugout 1 said:

Leesburg Georgia. 

 

Now the MJ is spitting oil into the air box. 🤬

I had seen a little oil in it so last weekend I replaced all the vacuum lines, the valve cover gasket and did the valve cover mod that I saw on here. My oil pressure has been a little high so I purchased a new oil pump and screen and was going to change all that out this weekend.  Guess I'll start a repair thread on that. Could the oil pressure be causing this or something else? The only thing I did not replace was the ccv check valve on the back of the valve cover. 

 

if it's a 4.0, there's no check valve in a CCV system, just a tube and elbow.  the 2.5 has a PCV with the valve.  if you haven't cleaned out the little line running to the valve cover, it might very well be plugged and the cause of the gasses going out the big hose (which is supposed to be fresh air coming in to the valve cover)

[ghetdjc320]

Have you tried running some seafoam through the oil? 

[JZLAJeep]

1 hour ago, Bugout 1 said:

I purchased a new oil pump and screen and was going to change all that out this weekend.  

You must be a lot faster than we are. Replacing the oil pump was an all weekend job by itself. Dropping the front axle to get the oil pan off (and then scrubbing and repainting the outside of the oil pan) was a lot of work. 

[Bugout 1]

1 hour ago, Pete M said:

 

if it's a 4.0, there's no check valve in a CCV system, just a tube and elbow.  the 2.5 has a PCV with the valve.  if you haven't cleaned out the little line running to the valve cover, it might very well be plugged and the cause of the gasses going out the big hose (which is supposed to be fresh air coming in to the valve cover)

Iv replaced all the vacuum lines and cleaned out the valve cover and breather vent tubes and did the mod to them that required cutting a 1/2" off and drilling a hole. 

On the back intake (closest to the firewall) isn't that a check valve the elbow goes into? 

 

I haven't tried seafoam yet. 

[Bugout 1]

[Pete M]

shouldn't be a valve inside, just a plain open elbow. 

 

blowby (gasses escaping past the rings) is super common on the 4.0s.  mine was so bad that I added a catch can between the valve cover and air filter to collect the oil. 

[Bugout 1]

Would high oil pressure be a contributing factor? or high revving? 

It also started last night to rev high upon start up but then dies down to normal. I know that could be a vacuum leak, TPS or AIC  - but could high revving be causing more oil to go into the air box? 

 

I'm going to check the blow by here shortly. Someone suggested loosing the crank case oil fill cap and seeing how much pressure is escaping. 

[Pete M]

oil pressure is irrelevant, as it's the air pressure inside the valve cover that pushes the tiny oil droplets out the tubes.  high revving will make the blow by worse simply by having more bangs per cylinder per second and churning up the oil in the valve cover so more drops can escape with the fumes. 

 

all engines have some blowby, but the little tube is supposed to be sufficient for sucking all the nasty fumes out and putting it back into the intake manifold so it can be burned in the cylinders.  in the end it's more annoyance that it's getting into the air filter than anything else.  comes with old engines, but it's not a death knell or anything.   

[Bugout 1]

1 minute ago, Pete M said:

oil pressure is irrelevant, as it's the air pressure inside the valve cover that pushes the tiny oil droplets out the tubes.  high revving will make the blow by worse simply by having more bangs per cylinder per second and churning up the oil in the valve cover so more drops can escape with the fumes. 

 

all engines have some blowby, but the little tube is supposed to be sufficient for sucking all the nasty fumes out and putting it back into the intake manifold so it can be burned in the cylinders.  in the end it's more annoyance that it's getting into the air filter than anything else.  comes with old engines, but it's not a death knell or anything.   

Certainly annoying because now its leaving large oil spots in the driveway.  

[Pete M]

1 minute ago, Bugout 1 said:

Certainly annoying because now its leaving large oil spots in the driveway.  

 

that's likely something else.  the oil from blowby should be ending up in the air filter.  but there are plenty of seals on an engine that can leak.    back of the valve cover, oil pan, oil filter adapter, etc. 

[Bugout 1]

1 hour ago, Pete M said:

 

that's likely something else.  the oil from blowby should be ending up in the air filter.  but there are plenty of seals on an engine that can leak.    back of the valve cover, oil pan, oil filter adapter, etc. 

It's coming from the air box. It accumulates in the bottom and drains / drips out slowly. 

[Pete M]

oh wow.  that's pretty bad.  I would run a compression test to see how the engine is doing.   but assuming it otherwise runs ok, after that I'd probably add an inline catch can and keep driving.   

[pizzaman09]

I had this issue on my 88 Comanche in a central Kansas Pizza Hut parking lot.  After a find lunch we walked out and found a 2 ft puddle of oil under the truck that originated.from the air box.

 

I went to the nearest parts store, purchased a PCV valve for a 4.0L, a rubber grommet for the valve cover and a new air filter.  I replaced all three items and it didn't put another drop of oil on the air filter for the following 2000 mile drive home.  

 

That truck had a PCV in it with some random rubber hose going to the air box port instead of the factory right angle hose setup.  I suspect the part I got at the parts store was a later 4.0L part.  

[Bugout 1]

So last night I checked all the new vacuum lines and the one in the back (closest to the firewall) was not clear even though it was brand new. I blasted air through it and it cleared up. Maybe it will be better now. 

She runs great, no smoke, no fouled plugs, so I'm gonna assume the compression is ok. I do have a compression gauge I may try later. 

[ghetdjc320]

On 10/20/2023 at 4:48 AM, Bugout 1 said:

I will say, every one of those that I’ve opened had a little metal “diaphragm” gasket looking thing near the base that clogs rather easily. 

[Bugout 1]

I think the issue is gone or at least lessened. Just drove an hour to the hunting land and back, no oil but...... I think iv decided to sell her and spend my time investing in the LJ.  I put the MJ up for sale before and then changed my mind so we'll see.

[Joe Dirt]

Quite a few ppl like mine but i have no idea what brand it is. Came with my xj parts truck.