Update... Engine flush, oil light, and vacuum leak!

[elwesso]

Got my engine flush done..... I am not really very happy by what it did, I can only see a minor difference in cleanliness... I guess it was mostly just stains (From the oil breaking down and bonding to the aluminum), and not really hurting anything... Moreover, the oil light duration time at cold startup is only a little different... Still about the same....

I guess that means some other things are gonna have to happen, like an oil pump replacement?? I hear its not too hard, just remove the front cover, and its a few bolts from there.... Not something Im looking foreward to, but I guess I'll do it if thats what is need be.....

Im running valvoline durablend 5w30 as per advice of Fred....

Next, I got my idle problem fixed.... Apparently I dont know how to adjust the IAC. Got it all taken care of now, idles nicely at 650rpm.... I had to screw it in all the way, and then screw it back out to get the idle good.....

[qship96]

Wes,have you had your oil pressure read at idle? might want to get it read before you replace the pump,as these rarely go bad.oil light may be coming on due to restricted oil passages in the engine,even though the pump may be fine.Have you considered trying a ester based oil,such as Redline,many have stated this oil does a much better job of cleaning than others.I run it in my q for the quality of it,and it has kept my internals spotless at 127,000 miles on my q.try surfing BOBISTHEOILGUY.COM for great info on oils and search for AUTO RX,a sludge cleaner many at the site swear by!

[elwesso]

That autoRX stuff looks too "infomercial-ey".... Id need to hear more about the stuff from people here..... Doesnt sound bad, but Id think the bilstein flush should have taken care of that.....

[qship96]

That autoRX stuff looks too "infomercial-ey".... Id need to hear more about the stuff from people here..... Doesnt sound bad, but Id think the bilstein flush should have taken care of that.....

I to,am leary of "additives",but out of all of them,this one seems to be the only one recommended on that site,they have some real good discussions there,kinda similar to this board,not alot of "kidde talk" like many sites.maybe Fred will chime in when he returns,he is a poster on that board and seems to follow the threads there.

[DAEDALUS]

Definitely don't replace the pump if it delivers 14psi or more when hot--won't do any good. Restricted passages would only increase oil pressure *at the sender*, as the oil has fewer/smaller outlets. When you removed your valve covers how did you cam lobes look? Did you remove any of the bearing caps and take a look under them? Visual appearance of bearings tells a lot.

[elwesso]

You tell me.....

http://www.nissaninfiniticlub....overs

I didnt remove anything while I was in there.... I am going to recover my passenger side here in a while..

[Q45tech]

A machine flush won't fix 5-10 years of abuse, maybe 100 flushes will clean it up but the damage [bearing clearances] were HOGGED OUT years ago when the oil broke down and reduced its lubrication properties.

I don't understand why people are so resistive to making some simple oil pressure measurements.........takes an hour including driving on and off lift.

[elwesso]

Problem is I have no idea how to do that nor do I know anyone that would do that for mne, at a reasonable price......

[qship96]

Wes,you must be upset with all the bad news regarding your engine sludge condition.look at the bright side,the acceleration is still great,who knows how many tens of thousands of miles of driving pleasure you will still get out of it! I have seen worse scenerios,where pristine autos get wrecked or stolen--------just maintain it,and Enjoy it while you got it!

[elwesso]

Thats the idea.... Im just gonna keep truckin until she dies, then I can drop a pristine engine and transmission into it... Or make it a NICO quality parts Q.....

[DAEDALUS]

Wes, if you're curious about the pressure, check around at the local auto stores. Seems you should be able to rent or borrow a gauge and a sender socket. The sender is admittedly in a tough place to reach, but much easier (and cheaper) than replacing the oil pump. It's on the driver's side of the engine, above the crossmember and near the oil filter. There's a small harness going to the sender. What makes it tough is that the sender is right next to the exhaust header. Nothing like slowly shredding the back of your hand on sheet metal while trying to thread the darn adapter in.

[elwesso]

Shredding my hand on sheet metal.... Its not something im not already used to....

i'll check up at my shop next time I go, I would assume they have one... If not, im sure the independent I use for most of my stuff would be able to do it.....

Just out of curosity, what will this tell me... I know its gonna tell oil pressure, but what is it gonna tell me to fix... If it delivers 14psi at idle, then that means something is clogged......

[Q45tech]

Your thoughts appear confused.

When your light comes on it means that the pressure is below 3 psi and there is no back pressure because the clearances in the crank or other bearings are too wide. Or the oil has drained back from the heads and you have yet to fill the oil passages at startup.The damage is that it is only going up to 4,5,6 7 psi not 14 psi minimum.

My 261,000 mile engine still is at 15 psi worst case after a few hours at 80 mph in Summer heat when allowed to immediately drop to idle. At 4,000 miles on Mobil 1 10w30 it is up to 17 psi [reflecting the dirt and viscosity [thickening of even synthetic oils].

You select your oil viscosity by making a oil pressure graph......the only scientific way

Graph the oil pressure at idle vs the coolant temp [from a Consult] in 1 minute increments from a cool to hot idle.........be sure to use a new filter and new oil as this is the worst case for pressure.

The pressure will start around 25-30 psi [depending on oil temperature] and fall progressively to no more than 14 psi at 650 rpm with 190F oil temperature.

Starting with Really cold oil and the warm up rpm [1500] can see 40-50 psi.

With oil lights coming and staying on more than 1 second good idea to cut open an examine the oil filter after each change......weigh the amount of copper [from bearing] - should see none with a magnifying glass on the unfolded filter element.

When you find any copper [other metals that you can see] death is imminent.

[elwesso]

I just had a couple thoughts....

1. Could the oil pressure sender be bad?? I would think that if I was seeing less than 3psi oil pressure I would hear some rocker cover noise or something else bad.... None of which I hear, it sounds just like it always has (without the oil light on)...

2. it didnt start doing the oil light until after I did the valve cover.... Do you see any correlation there, I inspected the heads to make sure nothing fell down in there, but I suppose I would rule it completely out....

[Q45tech]

Still resisting measuring the pressure, I see...........oil senders leak all the time but they never fail to work correctly. If anything the spring weakens and they turn off at a lower pressure.

[elwesso]

Alright.... I'll do an oil pressure check....

I need to know what to get.... What size adapters, etc... It doesnt look hard, something I could do here at home..... FSM doesnt help that much in determining which one i need (except its the kent more number).... I would probably go any buy a gauge that I could use myself....

Would it be a decent idea to install a gauge instead of the sender unit so i could monitor it in the cabin as well??

[DAEDALUS]

Not a bad thing, but you would have to run a line out, around and up to the cabin. And that line would have to be made to withstand engine compartment environments for a lengthy amount of time. Remember, you're right next to the exhaust manifold. Seems the risks of puncturing the line outweigh the benefit. I'm pretty sure I used my generic O2 sockets on the oil sender. They're probably 22mm or maybe 19mm.

[90Q45blue]

I would think that if I was seeing less than 3psi oil pressure I would hear some rocker cover noise or something else bad....

This is probably a dumb question but, what does a rocker cover noise indicate?

Nick

[elwesso]

Oil starvation...

[PalmerWMD]

For what its worth:Wes' engine sounded normal,when I heard it at idle, compared to other Q's.

Fred..

[elwesso]

Just another interesting tidbit...

Its been sitting for 2 days in the garage (which is about 40ish) and I fired it up and the light was only on for like 1 second...

[90Q45blue]

FYI, I just had my oil pressure send unit replaced and the part was super cheap...like under $50 or something.

Nick

[elwesso]

Was that including labor???

IF its like $20 or so, Ill give Joe a call!