curious... did you find anything out?

 

Me too, find anything out?

 

I asked him about this. He said oil got into the coolant but coolant didn't get into the oil.

I'll try some thicker oil. I need to change the oil but was thinking of trying something thicker than 5W30.

 

I've run Rotella 15w40 in my 5.9 for 260,000 miles now - and it still holds good oil pressure and doesn't burn oil... and in my 500 horse 383 boat engine as well. Can't beat it for the price. ...and my engine builder swears by that and mobile 1 and a couple others...

I seem to remember having a similar problem to yours but in my truck (ram 1500) regarding low oil pressure at idle... and the fix was a new sending unit if I remember right (it's been10 years ago)

 

I use mobile 1 20-50 and 15-50 in my wrangler foe 15 years

my trans van with the 5.9 magnum I use 10-30 mobile 1 but I have a huge 1997 viper oil cooler up front


try 10-30 or 15-40 first, it’s cheaper than cam bearings!!

 

Someone had already replaced the sending unit. Not only that but the old one was laying on top of the air cleaner and I thought perhaps some of the rattle may have been caused by that.

I know this is NOT the fix but I unplugged the connector in the meantime because the check guage light and the "dinger" would kick on when I'd come to a stop light and irritate me. Best I can remember the engine has 40 PSI of oil pressure at idle when the engine is cold, and the needle runs over the halfway mark going down the road. I think on average most engines have a pressure relief valve on the oil pump that blow off at 60 PSI.

It seems if the oil pressure falls below 30 PSI, the guage immediately falls to zero and the check guage light kicks on. So the least pressure the gauge will read is 30 PSI.

I had a similar incident with a Fiat 131 I used to own. It didn't have a guage but just a low pressure light. I believe it kicks on below 5 or 7 PSI. The light would kick on at idle when the engine reached normal operating temperature. I rigged up a mechanical guage and it had around 10 to 15 PSI at idle. I just replaced the light switch and it fixed the problem. Unless the sending unit the guy installed is bad. I seem to be seeing more and more faulty parts straight out of the box these days from these chain auto part stores. I'll rig up a tee with a mechanical guage and see what's going on.

Usually the first thing I do when I get a "new" vehicle is change all the fluids since I have no record on the vehicle. The oil doesn't look all that dirty but I have no idea what kind of oil is in it or how long it's been in there. I have noticed on cold mornings (in the 30s or below) the engine is much more quieter before it reaches normal operating temperature. After that is when I hear the diesel noise after letting off the throttle. Also the noise seems to start at part throttle above 50 mph.

Looks to me like if the cam bearings were worn, the engine would make this rattle either all the time or get worse as the RPMs increase.

I've got a couple of gallons of Shell Rotella 15W40. That's what my Fiat 124 Spider calls for. Well not actually diesel engine oil, just the weight. That's the only type of oil I can find "off the shelf anyway" in that weight for this engine.

Any of you guys ever use this stuff called Engine Restore? The guy below does all these weird experiments usually on junk push-mowers and claims it worked on his Ford tractor. I've watches several of his videos and he seems credible. He's also disproven allot of these snake oil products that claim to work.


Then he did a follow up video after a year:


So far I've put 200 miles on this van and it's not consuming any oil but thought I'd give it a shot just to see if it has any effect. I would say the engine has plenty of power and it does fine around town but it falls flat on it's face once I read 50 mph trying to get up to 70 mph on the interstate. The V6 just doesn't have as much ***** as my 350 Chevy van.

 

No surprises there... I’d probably just leave the mechanical gauge connected and drive the heck out of it for now... you’ve got plenty of oil pressure at idle to keep everything lubed... go with a bigger engine later if the engine craps out and you keep it, maybe pick up a 5.2 or 5.9...

if you need more pull and have 3.55 gears in it, might put 4.10s in it or look for a van rear end with them already in it to swap out...

 

OK so today I changed the oil. First thing I did after draining the oil out of the pan and removing the filter was put the plug back in and filled the oil pan with 5 quarts of gasoline and let it sit while as I was rigging up my mechanical guage and tee.
After about 30 minutes I drained the gas out of the oil pan. Not allot of sludge came out with the gasoline.

So I installed a new filter and some Shell Rotella 15W40 engine oil and that Engine Restore stuff.

I let the engine idle for quite some time, rounded up some garbage my wife had thrown out back, drove it around the block, etc. I realize the readings off the dash guage you have to take with a grain of salt but when the engine was cold it seemed to match the mechanical gauge (~ 50 lbs). Since this guage I am using goes to 160 lbs, it may not be that accurate below 10 PSI. These two photos were taken after the engine had been running for around 30 minutes.





So I thought that was taken care of. I drove 8 miles to work and when I came to a red light, the dash dinged at me and the dashboard said "check gauges". Once again the oil pressure guage was reading zero. Took off from a red light and the guage shoots back up to the mark in the above photo.

When I pulled into the parking lot, the guage went to zero again but after revving the engine up a bit the guage shoots back up to the above mark and stays there.

Since it's dark and I was on my way to work, I didn't have a chance to pull the doghouse off to see what the mechanical guage says when the dashboard guage goes to zero.

What do I think? I think the dashboard guage is messed up. When hot, the guage in the dash does not match the mechanical guage so I believe for whatever reason the guage cannot read anything below 30 PSI. Just goes to zero.

Also I realize in 1994, Jeep was a carryover from the AMC/Renault days but I bought that thing new and no matter what the engine temperature or RPM was, the oil pressure guage always read 50 PSI no matter what. They may have well just put a low oil pressure light in the dash if the guage just read a consistent 50 PSI.

 

The Magnum engines are known for weak oil pumps...

 

Yup, I hate when I’m right about this problem, I have dealt with this a few times over the years,

well, you can try to change the dash gauge but that’s not the problem

cam bearings have too much clearance,

this will NOT cause any extra valve train noise, it will only bleed out too much oil at idle when oil is very hot

instead of doing all the work to pull the camshaft ( take the whole front end apart including ac condenser) work the puller and installer to replace the cam bearings and try to line up the holes in the bearings to the holes in the block ..........just replace the engine with a good salvage yard one or pull your engine and have it rebuilt

if you get everything taken off to replace cam bearings , you don’t have that much more to pull the engine

I have tried everything you could think of to avoid the inevitable, thicker oil,high volume oil pump etc.

if you get the cam out, shine a light inside and the cam bearings will be black or dark color

as I said it’s a cool looking van, I would invest in getting it running right



viperdave