Hey everyone, I just picked up a pretty clean 2004 Disco II Trail edition with 122,000 miles. PO think it needs an oil pump as it recently started ticking. It has been sitting for about 6 months since this happened. I actually bought this for an LS swap candidate, but I'd like to see if this motor in fact needs an oil pump. I'd like to get it running and drive as is for a while until all of my swap parts have been accumulated.

Here is what I know so far.

Oil pressure test:

Cold idle: 50psi
Cold 2k rpm: 54psi
Hot idle: 16-18psi
Hot 2k rpm: 45-50psi

This makes me think the oil pump is fine. When I start the truck cold first thing in the AM, it sounds great. No tick or anything. After 1 to maybe 2 minutes, I start the hear the tick. I put my autoenginuity scanner on it and the ticking started right at 142 degrees. I understand the slipped liner tick, but believe that usually happens at a higher temperature range. I also listened to my stethoscope and the tick seem to be coming from the front passenger side valve cover. Drivers side seems nice and quiet. I'm not familiar with rocker arm failures, but I'm leaning towards them as maybe the reason. The confusing part to me is that it starts after 1 to 2 minutes when cold and remains when the engine is up to temp. Am I correct in thinking that its probably something in the valve train?

Side note, I'm currently flushing the coolant and replacing the thermostat as it seems to be running a little warm (217 degrees) when up to temp at idle.

Thanks in advance
Sean

 

Rocker issues do pop up from time to time. Another thing to consider is that it may be an exhaust leak on that bank as well

 

Oil pressure looks fine, likely not a broken oil pump or walked cam bearing causing rocker arm tick. It could be upper end tick, but that is actually kinda rare. We have had a member who lost a hardened pad off of one of his rockers. I guess it is worth a shot to pull the valve covers and rockers and see if you notice anything. Make sure when it comes apart that the rocker shafts were installed correctly with the holes facing down and that he oil feed holes in the rocker towers are not blocked with sludge. Good luck!

 

I have that tick after warm up. The interesting thing is: After an engine flush + oil change the tick is gone. I flush with Liqui Moly Engine Flush as directed, one and a half bottle, put in synthetic blend (10W40) and ticking is gone. At least for a while. After about 2,000 Miles or so it comes back. The older the oil the more persistent the ticking gets. Then after flush and oil change it is gone again. I suspect a slipped liner and carbon build up creating more friction. I see small black dots in the drained oil, which dissolve when I squeeze them with my finger tip. Otherwise the engine has no problems, runs smooth, no codes.

Maybe the PO was a bit negligent with oil changes. These engines need them frequently, about every 2,000 miles. Try several thorough oil changes with flush and see if things improve.

 

Haven't I been reading on here that 2003/2004 4.6 engines don't get slipping liners... I would lean toward vacuum leak or thin oil. No reason to run 10w in California or Texas. No good reason to run synthetic either in such an old flat tappet engine. Try 15w40 Rotella.

 

Ok, I think my next order of business will be to do an engine flush. Once that is done I'll refill with 15w40 and a wix filter. If it's still ticking after that, I'll go ahead and remove the valve covers and inspect those components.

 

Found this on another post. The tick referenced here starts right where mine does (140 degrees). Thinking I may need to pin some sleeves on the passenger side. If this is it, it would explain why it starts after a minute or two and not right off the bat.

 

Check the Oil Separator passenger side valve cover, mine was pretty much solidly clogged and I would get a tick every now and then, did the PCV mod the tick is gone.

 

I don't understand this argument. At operating temperature the viscosity between 10W40 and 15W40 or even 5W40 (what the manufacturer recommends) is negligible. It makes only a difference when cold, but that is actually bad when using a ticker oil.




I had tried 15w40 Rotella T5 diesel oil before for almost two years. PO used 5W40. The only difference I could notice was a slightly lower engine noise when not at operating temperature. It didn't do anything to the ticking nor did it reduce the amount of oil leaking (although some claim thicker oil would help). After doing some research I went back to a lighter (gasoline) engine oil for several reasons. Catalytic converters, breakdown temperature, cleaning additives. I don't say that diesel oil will lead to catastrophic failure, but there are better engine oils for the D2 for sure.

 

My takeaway from reading in endless posts here: People tried everything: oil pump, bearings, lifters and last but not least pinning the liners. The thing that helped in most cases was pinning.