Ok guys and gals this started last night. 60* night with last few days in the 100s. After I started the disco and it sat for 10-15 while packing up to leave my buddies a top end noise began it was a tic tic tic tic that increased with engine speed at P N and D just did oil change several days ago and started using only rotella 15/40. Car was not over heating temp was nominal but cab heater was on cause the woman was cold. After 10 mins driving the tic dissipated and went away. Now I didn't have an oil pressure light come on and I know the sensor is good, I replaced it not to long ago. So question is what could it be? Isolated it to the passenger side and seems dominant right under the valve cover. Worn rocker, rod, tappet? How can I differentiate between them? I need to snug up my valve covers I know but oil level is good, so should I rip off that valve cover and inspect? And if so what should I look for? I have never R/R these parts before except in passing while doing heads.
Thanks all, Steven and Ashley
98 disco 199xxx miles.

 

Valve train noise can come from lots of things, including starving for oil (gunked up passages). With new valve cover gasket on hand you can remove suspect cover and exam things. You can even run engine with cover off and press on various components with a stick to see if sound changes.

When you remove be sure that small washers in valve cover gasket don't fall out and into the motor... Follow RAVE exactly, re-assemble of the valve train the wrong way blocks oil passages.

Pages attached from RAVE. Pix of what you may find, if really gunky then the bottom end will look the same, like the oil pickup.

If on the right side of the motor, when you are doing this the heater core will be disconnected, so plan on some coolant refill and air purging. Also good time to reverse flush the heater core.

Also pix of cut away of valve train on a D2, this is the rare "low rider" chrome version, with rapid swap coil wire configuration (once you put a firewall behind it things change)....

 

Thanks buzz great pics for reference! Hopefully since I'm away from the ER this morning till thurs I can rip it off and inspect it. Thanks for the info.

 

With those miles, I wouldn't worry about it.
Even with less miles I wouldn't worry about it.
But then again, I don't worry about much if anything.
Worrying is a waste of my time.

 

Well checked the other day and oil ended up being low so I threw in some Lucas I had to blend with the rotella and it quieted right down. Need to find and fix this oil leak, think it's valve covers that need tightening and a cooler hose that gets wet a day after being cleaned. So no valve issues yet thank god just my absent mind not checking oil first. I'll get to the bottom of this leak. Still looking for local radiator shop with a decent price for rodding.

 

Cooler hose has an O ring inside that might be bad. And the whole hose can be dry-rotted poop as well, had to replace mine. When doing this consider an oil pressure test as well. And according to Murphy's Law section 345.0981(a) - a slight increase in viscosity is rewarded by a faster leak. Would check daily (more frequently while on a long trip) until you are sure it is resolved. The rad shop I found was in the part of town out by the agriculture community, he did bus, tractors, and off road heavy equipment (that's his boat payment). Rover rad is a teacup to these guys.

 

Yea think I found one guy works on rvs, boats,quads and hot rods. Gonna call for a price. And that cooler hose looks like it's rotted out most cooler hoses and o rings will be replaced when I drop rad for service either scrap yard parts or new. Saw some yard cooler lines that looked pretty good. But will have to order o rings From AB.