What would your Engine do if it was Badly Sludged

[JCCADILLACMOBILE]

.. Or how would you know? Would there be "Signs?"

Im wondering if my 1985 Jaguar XJ6 4.2L Inline-6 is a "Known Sludger," OR if having the Oil in there for More than a year (Which i added SeaFoam to 15 miles before Oil and Filter change, the same oil that "Only" got 40Psi Hot, unknown Viscosity, all that good stuff) Contributed to "A Lot of Slludge."

I have the Recommended 10W-40 in there, as ive talked to other Jaguar owners, and alo i couldnt exactly find my favorite 20W-50, as actually the Jaguar seems to be made for the 20W-50 in all but Winter... nevertheless, 50 seems to be this car's High Number. Now, even with the 10W-40 (2 Qts 5W-30, 4 Qts. 10W-40, 2 Qts 20W-50, yes it takes 8 Quarts) .. I see Oil Pressure of 60-65 Psi on Start Up (It never goes above 65 Psi because Jaguar has a "Relief Pressure" of 65Psi.. However, after about 10 minutes, it STARTS to have closer to 40 PSI when Hot, THEN goes back up to 60-65 Psi wihile driving.

Ive never let it run for "An Hour or two" driving it normally or on Highway, due to Alternator Issue at this time.

However.. People here have said that "65PSI is a good Pressure" for while Driving. if so, then thats good.. They also say that it takes 20-30 Minutes for the Engine to Fully warm up, so perhaps its not fully warmed...

But is ANY of this an indication that i might have a nice amount of SLUDGE int he Engine? The Engine SEEMS to run well, and SeaFoam and others are in my Fuel, to clean Gum and Varnish there (Old Gas, more than a year old, then i RAN OUT, had to add 5 fgallons, now im cleaning and adding, happy it works.. Runs pretty well too!)

.. But is "Oil Pressure" an Indicator of Sludge, OR How would i know if my Engine is dealing with Sludge?

It SEEMS to run well.. but nevertheless, i am wondering how one would know if Sludge is there, as im just speculating, guessing, and using SeaFoam, IF Sludge if helping sela something i dont know about. (Not a Drip of a Leak so far and i want to keep it that way.)

Thanks! Thats Post 3, for today ill post Tomorrow.. - Thanks All!

 

[willix]

If the sludge crystalizes inside valve covers & other internal parts can flake off & clog oil passages causing oil starvation to moving parts. The sludge it self I believe would just mix with the oil and flow. The problem is when it builds up on parts, hardens & chunks off. Yesterday you posted a thread indicating electrical issues and You really need to have a healthy charging system to have any sort of faith in the dash gauge ballpark accuracy, all gauges.

 

[brandini]

I know it seems counter-intuitive, but have you run lower weights? If the relief valve is opening at low rpm it's just wasted flow. Also, do you have any idea what oil temps are running?

 

[meangreen01]

http://www.ridgid.com/Tools/SeeSnake-micro

Through the drain plug, fill hole, intake, etc...

 

[Michael_P]

MMO. Several applications starting with a very low dose and gradually work up. Short OCI's.

 

[ZZman]

Low oil pressure could be a sign.

Tearing apart your oil filter and seeing alot of gunk in the filter pleats could be a sign.

Your engine dying could be a sign. (parts failing due to sludge)

Engine making loud noises could be a sign.

You might try a Jaguar Forum and see if any owners report any issues with that engine.

The best way to get an idea is to pull a valve cover and look around.

 

[ProStreetCamaro]

When our fords sludged up what would happen is the loose sludge in the pan would randomly be picked up into the pickup screen and oil pressure would suddenly drop to 0 and the lifters would start tapping. Pull over and shut it off for a few minutes and it would fall back down and we could drive again for a while till it sucked it up again. Dropping the pan and cleaning everything out and installing a new pickup screen would get us another 10 to 20K till it would happen again.

 

[willix]

Old Jaguars are quite a challenge to say the least. Many have given up and added a SBC conversion and done away with the 99% of the nightmare. The SBC conversion is common in those cars.

 

[askani79705]

Rotella 5w40 seems to keep the sludge at bay and it's real reasonably priced

 

[Audi Junkie]

Biodiesel.

 

[tgmiller77]

I also have an 85 xj6, I run Maxlife 20w-50 and the engine loves it. Don't run thin oil and change it every 3000 miles and these engines will run forever.
Your oil pressure readings are good, but one thing you should look for is the tappet hold down kit installed on the exhaust side of the tappet guides. Take a flashlight and check through the oil filler and if you don't see a little bar holding the guides down do it soon! They cause lots of damage when they work themselves loose. Start at jag-lovers.org.
Greg

 

[Steve S]

If you are asking how to tell if you have sludge in your engine. Remove the valve cover and see how it loks . A wee bit of sludge doesn't matter when there is enough to clog the oil pump pickup screen or clog the oil returns in the cyl head there will be serious problems . Sludge usually accumulates first in the non pressurized areas in the engines.

 

[Win]

The XK Jaguar engine ( as all Jaguar engines are ) is durable - it's probably possible to sludge one, but I've never heard of it.

The only issue I've ever heard of is the need for the stakedown kit as referred to above. It's unlikely that your engine would not have this, but you should check to make sure.

Thick oil for Jags seems to be the mantra, that just won't go away. It won't hurt them, but lighter oils were specified by Jaguar. My V12, which comes from the same era as the later XK engines, allows for 10w-30 for normal climatic conditions, so 10w-30, or 5w-40 is what I normally run in it, depending on what I have on hand. Jaguar even allows for 5w-20 in cold temperature operations.

I would avoid 10w-40 like the plaque, and use either a 5w-40, or 15w-40 if you want to use a 40 weight.

 

[Nickdfresh]

Doesn't a sludged engine quickly blacken the oil?