oil pressure

[mikeE72]

hi im 15 and farely new to trucks though i am a very good dirtbike mechanic.on my 88 2.9l ranger my oil light came on as i was playing in the mud provided by the three inches of rain we got on saturday. i was wonderin if someone could take me through the steps of testing the oil pressure. also where is the sending unit for the oil pressre check light. thanks

 

[Psychopete]

hi im 15 and farely new to trucks though i am a very good dirtbike mechanic.on my 88 2.9l ranger my oil light came on as i was playing in the mud provided by the three inches of rain we got on saturday. i was wonderin if someone could take me through the steps of testing the oil pressure. also where is the sending unit for the oil pressre check light. thanks

That is a oil level indicator light. There's is usually an oil pressure gauge in your dash cluster, but is usually not close to accurate.

On my '88, when it read no pressure on the gauge, it really didn't have much pressure at all. I had cracked a head, drove, and eventually ate up the bearings until hardly any more oil was getting to the lifters.

The oil level indicator is on the side of the oil pan, though I am not too fimilar with the circuit since I've never had an issue with it (not sure if mine even works ).

A mechanical oil pressure gauge should have the fittings to hook it up to the stock sender. The stock sender is on the drivers side of the engine, more towards the front. Mine was sort of cylinder shape that tapered in with a single wire that attached to it on the end. You might be able to find the sensor wire and follow it to it.

Pete

 

[AllanD]

The "Check oil" light isn't pressure it's level.

there's a sensor in the drivers side of the oil pan.

AD

 

[mikeE72]

on the 88 rangers there are two oil related lights one is a check oil light"low level light" the other is a oil can with a drip coming out of it since the other one is a low level light and since there is no pressure guage on 88s this must be the pressure light. i know the low oil is in the pan and i found the pressure sender in the block toward the front of the engine on the drivers side but know i cant figure out how to get it out so i can pressure check my motor. i tried an adjustable but there is no room to turn one. ive heard of a socket with the same number and shaped sides as the sender but i dont know where to get one.

 

[mikeE72]

the whole reason i was going through this was because after i brought the truck in from playing in the mud the normal tick that it had had increased dramaticaly an the thing sounded like a diesel. after checking the oil level i noticed the oil looked veyr clean and i began wondering if the owner before me changed the oil with a detergent oil breaking up the preexisting sludge in the motor and causing it to circulate and plug something up.when i drained the oil however it was totaly different than what appeared on the dipstick. so i threw some new oil in it and a new filter and the dieseling sound was decreased to a slight tap. now its much better than before but i did two more oil changes with little to know affect on the tapping. should i just run the truck as it is and accept that its getting older or is there something else i can do. also the tap seams loudest at about 1200 to 1500 rpm. and if i do keep running it like this will it hurt it or just be a little noisy

 

[Big Jim M]

Lets forget a "tapping" sound and talk clicking or knocking. Knocking is a definiate "thud" that repeats itself. "clicking" is a top end sound that repeats itself..
Knocking is a BAD sound that indicates unusual wear on the bearings in the lower end of the engine. CLICKING is usually a valve sound that can be caused by any one of several worn parts having to do with opening one or more valves.
If the engine KNOCKS shut her down! If the engine CLICKS (which I think your tapping sound is) one can use a substitute EAR to listen closely to the engine and find which valve it is that clicks. Repair parts are easily aquired and installed for most valve clicks in most engines. Most engines can have their valve covers removed and the rocker arm adjusted, or a longer pushrod installed or even a new rocker arm to stop the clicking. There are exceptions however. Some engines require extensive removal of intakes or even heads to repair the click.
Big Jim

 

[mikeE72]

thanks jim yes it has a clicking sound at idle and above but the pitch of the sound seems to change and get deeper at 1200 to 1500 rpm.but it i think it turns back into the clicking after that. i cant tell even with hose where its coming from specifically but it is coming from the drivers side head

 

[holyford86]

on the 88 rangers there are two oil related lights one is a check oil light"low level light" the other is a oil can with a drip coming out of it since the other one is a low level light and since there is no pressure guage on 88s this must be the pressure light. i know the low oil is in the pan and i found the pressure sender in the block toward the front of the engine on the drivers side but know i cant figure out how to get it out so i can pressure check my motor. i tried an adjustable but there is no room to turn one. ive heard of a socket with the same number and shaped sides as the sender but i dont know where to get one.

Snap on sells a socket for that but be prepared to pay out the ass for it

 

[mikeE72]

now i havent checked the oil pressure yet because i dont have on of those sockets but lets say i dont have enough oil pressure. where should i start i have had suggestions of the oil pump and screen but in the haynes manual you have to lift the whole engine to drop the oil pan, is there an easier way to do this. also took it out for a drive on road for the first time and the tick or nock seems louder when your decelerating with your foot off the gas. and it got louder as we neared and passed 2000 rpm

 

[Big Jim M]

Mike low oil pressure is a rare happening in a modern engine. If the pressure were low ALL of the valves would be clattering and screaming at the same time.
If what you have is a noise coming from the piston, rod, or crankshaft you will soon need another engine.
If the noise is coming from a valve related problem you need to find out which valve and what the repair for your engine is to make it shut up.
Checking the oil pressure would, most likely, only tell you that there is PLENTY of pressure.
Big JIm

 

[mikeE72]

i have no idea where the soubd is coming from because so many different people have such different ideas. i think its coming from the top end but at about 1500rpm the sound changes and people told me its from the bottom end. i think most of the noise is coming from the topend though. plus if i had adaquet pressure why would my oil pressure light be on. and i dont think its a faulty sennsor because when i first run it amediately after changing the oil it will flicker and go off but then come back on. ill update you after i check the oil pressure which like you said jim may not prove anything but it will be one thing checked off the list of idease local mechanics gave me and may point me in the right direction. and jim i think all of the valves are chattering because i couldnt pinpoint where the noise was coming from at all. thanks for the advice

 

[MAKG]

Actually, below-spec oil pressure is common on 2.9Ls due to a known design problem with oiling cam bearings. It can stay that way for a long time; it's not seriously low. 2.9Ls are also notorious for developing several different ticks. People seem always to blame lifters (and sometimes, they do stick internally, leading to air gaps in the valvetrain). But injectors tick as well, and the tubular fuel rail design seems to support waveguide amplification, at least sometimes. This is largely benign, just annoying.

Oil pressure spec is 40-60 PSI at 2000 RPM, fully warmed, but if you're seeing over 5 PSI at idle, you're probably OK. NEVER measure cold oil pressure; it is always far higher.

And here is what I think is really going on. YOU'RE LUGGING THE ENGINE and it's detonating. Anyone who powers a 2.9L at 1500 RPM needs to be forced to bore the block with their fingernails.

And FYI, 2.9Ls have adjustible valves, but they can't be adjusted correctly (with the engine running) because they are at the tips of the rockers instead of on the pivots like SBCs. Use it to tighten up nonzero lash, but DON'T overdo it. A loose valve taps a bit. A tight valve leaks and burns very rapidly (especially on the exhaust side).

 

[mikeE72]

i tested the oil pressure today and though i tested it cold with straight 30 wt oil and the front of the truck slightly elavated (just wondering if these things could throw off the test) the highest reading we got at 2000 rpm was 8 psi though i didnt run it for very long also there was sludge on the pressure sensor when i took it out.

 

[Big Jim M]

Houston...we have a problem! With cold 30W in it you should have a reading of 40 or better..
Big JIm

 

[mikeE72]

thats what i thought. so now that i know it has hardly any oil pressure where do i go from here. i discused it with my dad and we were thinking a new oil pump and screen. though a few people talked about the cam bearings.
happy 4th
going to go blow something up