NEED TIPS

So i knew my xj had a problem with sludge in the head. this was not my fault because i have only owned the car for 2 years. so when i pulled the valve cover i was shocked to see how much built up there was. I got pulled out the wet vac and removed ALL of this build up. I have purchased a new valve cover gasket and cleaned out the valve cover also. My question is does anyone have any tips for when i am putting everything back together that i should know before its to late?


Thanks in advance for any replies
-Ian

you might want to pull the oil pan and make sure the pick up screen is free and clear. while you have it off you can de sludge the bottom of the oil pan. mike

1. Start using a quality diesel oil like Shell Rotella: http://www.shell.com/home/Framework.../iwgen/products/triple_protection_detail.html

2. Service the CCV system.

3. x99j has good advice, but I would run the diesel oil for awhile first.

4. Always include your BASICS in every thread--year, engine, etc.

Frequent oil changes will help reduce sludge.

Do you know the history of oil changes on this engine?

Sorry about the lack of info. I got it all taken care of today. I have a 1996 XJ with the 4.0 I dont know the history of the engine but when i pulled that valve cover yesterday I found out more than i wanted to know. Thank you again for all the info guys it is greatly appreciated.

-Ian

XJ_holmes said:

Sorry about the lack of info. I got it all taken care of today. I have a 1996 XJ with the 4.0 I dont know the history of the engine but when i pulled that valve cover yesterday I found out more than i wanted to know. Thank you again for all the info guys it is greatly appreciated.

-Ian

Click to expand...

One other thing to check is to make sure the correct (if any) thermostat is installed so that the engine reaches normal operating temperature. Stant SuperStat Premium 195 degree.

joe_peters said:

1. Start using a quality diesel oil like Shell Rotella: http://www.shell.com/home/Framework.../iwgen/products/triple_protection_detail.html

2. Service the CCV system.

3. x99j has good advice, but I would run the diesel oil for awhile first.

4. Always include your BASICS in every thread--year, engine, etc.

Click to expand...

Hey joe, didnt you recommend something to add to the oil to clean out sludge? I swear you recommended some type of solvent to be added to the oil a couple miles before you change the oil.

Do NOT buy CCV valves/ gaskets from the dealer, you will get raped. I just bought front and rear valves from rockauto and they were easily 1/4 of the price. Pretty sure MOPAR just re-badges dorman parts anyways.

I have added one quart of ATF to engines in the past and run the engine for about 15-20 minutes at idle, not under a load, then drain and change the filter and fresh oil.

Lately, unless there is a suspect stuck lifter, I just let nature take its course with the diesel oils.

There are commercial engine flushes out there, Seafoam being one of the most popular.

I drained a quart of oil and added a quart of ATF and let it run at idle for about 20 minutes. I also have replaced the thermostat before when i replaced my water pump so i am sure i have the correct one in. after the ATF was in i used a diesel grade motor oil like you guys mentioned. About the CCV valves i found out after about 2 hours on the phone that i was better off by not going to the dealer for them. they wanted insane prices for the stuff and mine wasn't even broken so that did not need to be replaced.
Once again thank you guys for all the info, it was very much appreciated and i think i just added another 100k to my engine.

-Ian

Unless something is broken/missing you don't need to buy anything.

CCV consists of a filtered fresh air intake from the air filter box to the front grommet on the valve cover. The rear grommet on the valve cover has a metered orifice in it with a vacuum line attached that runs to a port on the intake manifold. You just need to make sure that the orifice in the rear grommet, the vacuum line to the manifold, and the port in the manifold are open. Drill bit or stiff piece of wire to poke through the orifice and port, and try blowing through the vacuum line.

Even if you needed to replace the grommets and such just go to NAPA--they may list it as PCV stuff, but what the heck can you expect from counter monkeys.

So the valve cover is back on oil has been changed and everything is looking up but i still have a problem with my oil pressure gauge. I have read alot about this problem I am having but no ones seems to be the same as mine and I am not quite sure what to do and was hoping you guys could once again save the day.

First i have replaced the oil pressure sensor that threads in twice and i know i have to correct one in there but when i turn my car on the gauge reads way above 80 it actually goes all the way to the screw on the gauge face. then when i turn my car off but have the power on it sits still above 80 just not as far.

I think something is wrong with the gauge itself and I dont know if it is possible to take apart my dash and replace just this oil pressure gauge. That is the one option I have come up with but I dont know if it is possible. My second option is to ditch the oil pressure sensor and replace it with a mechanical oil pressure guage and mount it where ever i please in the car.

So my question is what tips can anyone give? Has anyone had this problem? and what do you recommend I do?

Thanks for all the help
-Ian

First, you should check the oil pressure with a mechanical gauge for peace of mind.

Double check the wire on the sender.

The 96 is kind of a b*stard year and I don't have the FSM for 96.

95 and earlier if you remove the wire from the sending unit, then key ON, the gauge should peg high--exactly what you are seeing. Then, if you use a jumper wire and ground the wire to the body/engine, the gauge should read peg low. This would indicate that the gauge is working and the sending unit is the issue.

Now, I don't know the "proper" test for the 96, so maybe someone else with the FSM for 96--Kastein, you out there--will chime in.

1996-
Ign switch on for test, engine OFF. (!!!Ign off after test!!!)
-If tests OK then sender is suspect next.
-------------
Oil - wire at sender- Disconnected Instrument Panel Gauge goes to high end of scale.
Connect wire to ground with jumper - Gauge goes to low end of scale.

(Note: the sensor is real easy to mess up during oil filter change, or work in the area. Also readings change as high miles common. )

----------
1996 Coolant Gauge Sender- At rear of cyl. head.
Same type test= Disconnected- low end of scale, Grounded - high end of scale.

(Note: Sender is to gauge ONLY. Front sender at thermostat is to PCM ONLY.) ( Changed in 1997 to front, only one)

Only tighten to snug as they break easy. No thread sealer - grounds thru threads.

Just a thought-

The sludge. If everything seems normal otherwise, and no strange noises. Run that diesel oil and some highway miles, say 1 hour or more at a time. Best way, as hot fresh oil cleans great. Check dipstick often and change it, while hot, when it gets dark. As it gets cleaner that will take more miles per change.
The detergent in oil starts strong and gets weaker the longer it is run, Too long for the conditions and it starts leaving the sludge behind, which builds up.
Change it immediately, while hot, after at least a 20 minute running.
Mostly short trips of 10 minutes running or less IS SEVERE SERVICE.
The 'Fast Flushes' run the risk of too much gunk, too fast and clogging filter, lifters etc.

As I see it --JMHO, YMMV.

Good Luck,
Orange

thanks again for all the info it was a great help I got all the sludge cleared out ended up installing a mechanical oil pressure guage and it is running great.

thanks,
-Ian

In case "service the CCV system" slipped by, make sure that you look carefully at the vacuum line inside and out. It tends to clog with sludge, especially at the elbows.

before i put the valve cover I made sure that the ccv was clear and once i put it on and turned the engine over i could feel it blowing air out so im sure its clear of anything. I spent 3 days cleaning out all the sludge from the head and valve cover so if I missed anything I would be very surprised!

-Ian

you might just want to go ahead and replace the grommets and both CCV's. it will literally cost you like 10 bucks. The grommets can dry out and leak.

I just replaced them on my 2000 and the grommets crumbled to bits, and the CCV's shattered. might want to considered taking the cover back off to do this.