gohawks

I took my 1988 4runner 3.0 into a respected mechanic today (35 years experience with imports).

Upon initially listening to it before I left he said it was not a bearing, but would check into it further.

He calls me at 4:30 today with a run down of testing:

1) Warmed engine to 192 degrees and used stethascope to pinpoint noise. He pinpointed it to driver's side front of block.

2) Drained and collected oil. Went through oil drain with scope/camera and inspected crank and rod journals. No obvious blueing or excessively heated areas according to report.

3) Tested oil sample and found no metals, heavy or suspended (it should be noted I changed my oil 200 miles ago)

4) Removed spark plugs and inspected cylinder walls with camera. No visual groves or marks from wrist pin (NOTE FACTORY CROSS HATCHING STILL PREVELANT)

5) with plugs out & rotating engine with wrench a noise is heard at oil pump area when crankshaft is rotated back and forth, possible worn oil pump gears.

6) Tested oil pressure at 187 degrees with 10w-30 oil
Idle pressure = 7.4 psi
2000 rpm = 32.2 psi
3000 rpm = 36 psi

all fall within factory specs. Noting that pressure at 3000 rpm is at bottom of spec.

His diagnosis is excessive clearance in oil pump. He says he has seen this before and that he doesn't see it as being a problem at this time. He recommends keeping an eye on the pressure gauge. He has seen this in a 4Runner one other time and it was misdiagnosed by another Toyota dealership as a main bearing. He also recommended I switch to a heavier oil (20w-50) in the summer and 10w-40 in the winter. He told me to stop using Pennzoil (I know the Pennzoil reputation I just followed what the PO had been using) and to switch to something like Castrol with a higher GLI rating??

3 hours of labor @ $78 + $7.00 shop fee + tax = $257.87 :pat:

Estimate to replace oil pump = 10hrs labor = $780 + $158 for pump = $938.03

One question I have is would it have been helpful to pull plug wires to see if he could isolate the noise to one cylinder? If he pulled them one at a time through all 6 and it didn't knock then it would have ruled out bearings for sure? Am I wrong?

callmej75

I'm all about this thread...I got the same noise.

gohawks

Short of dropping the oil pan to check all the clearances I don't know what else I can do to diagnose......and my wallet is light enough after today.

Saint_Berzerker

heck, you can get a new engine for around a 1000.00, lol....without labor of course

gohawks

Where can you get a "new" engine for $1000?

I think orient is up to $2300 (shipping included)

I see a couple of ebay ones for $1500 or so, then add in shipping, and who knows what the quality is like, just because it has been remanufactured doesn't necessarily mean it is reliable.

I think a $1000 "new" engine is a myth in terms of the 3.0

Add the fact that there is no way I can install myself. Alldata R&R for the 3.0 is something like 16 hour as well

Elvota

I am by no means an expert, but it does seem this mechanic was really thorough, so I might put some weight into his diagnosis.

That said, you might research what it takes to change out the timing belt on this engine. It's not so hard if you have a standard set of metric tools and some attention to detail.

The relation between these two tasks is that you have to remove the belt to change out the oil pump. So, new belt... easy enough to put on a new oil pump. Should save you some considerable labor and maybe parts cost as well, depending on mark up.

If you are not up to the wrenching, you should inquire as to how much a new belt would be if the mechanic does the oil pump repair. It makes sense to change it with the work you are doing. May look at replacing the water pump as well.

My 2 cents.

DirtCheap

He probably meant a used engine in running condition. Their is no place that I, am aware of that sells them for that price. Be careful buying a used engine, you could buy someone's elses problems.

gohawks

Thank you for your reply Elvota, I'm looking for some confirmation on this to make me feel a bit better.

The problem with changing out the oil pump is dropping the pan. According to alldata.com you must drop the differential to drop the oil pan. This adds considerable labor to the job. Some say you can undo the motor mounts and jack up the engine to get the pan off, but this mechanic would go by what alldata tells him. You are correct with the timing belt correlation though.

Elvota

Yeah, you do have to drop the pan... although you might be able to sneak it out without dropping the diff/ lifting engine.

With my SAS it's not a problem. Maybe an excuse for a SAS.

gohawks

I just went to my other mechanic. He said looking at the journals through the camera was a waste of time and money and that you wouldn't see anything. He insists that the noise originates from the back of the motor.

sigh. I don't know what to do at this point. She runs fine, just that slight noise is so worriesome.

callmej75

Mine has been knocking for the last 3-4 months. I was told by my brother-in-law that it sounded exactly like a wristpin. I am inclined to believe him because the noise hasn't changed pitch any. He just told me to use 20-50 oil and it will quieten it down and prolong the life til you do get the money to get it fixed. Sounds like your first mechanic was telling you the same thing that my brother in law said to do. I just live with mine...if it blows...then looks like i'm down a few months til I get another motor swapped out...and I'll be damned it if will be another 3.0!

gohawks

Mine is my daily driver, and I rely on it for work and some occasional camping trips so I would like it to be as reliable as possible.

In fact I am/was going to take it on a big trip this summer out West. I would hate to get stranded in the middle of western Nebraska with a blown motor. I just want to have SOME degree of security before I take off on something like that.

gohawks

I know the last mechanic told me he inspected my oil, but I seriously doubt he did any sort of real detailed analysis.

I think I'm going to collect my own sample and pay the $20 for my own piece of mind.

This should be able to give me an idea of bearing wear correct?

callmej75

Mine is my DD too...so I feel your pain.

snap-on

Like i said man, i never thought it was bearing noise.

oil pump is a good canadate.

Im one for just drive it till it gets worse. Either the noise will get louder, or when your changing oil ever 3k miles you notice a lot of forign material in it (bearing material)....

either way assuming you have oil pressure (like he said watch the gauge) then i dought the motor is going to up and seize up or otherwise on you just all-of-a-sudden.

gohawks

Snap-on,

I was actually hoping to hear that from you. Thanks.

Quakefire

Make sure the motor is good and warm before you collect the sample, it will drag more of the crap out, and a camera would be a wase of time as the bearings and important parts of the crank are covered up by things like main caps and such. The other thing you should do is cut apart your oil filter and look at what its been catching.

Radyota

I was just going to say that about the filter! Yes, the oil pan CAN be dropped without removing the diff. I personally did it once using the loosen motormount/jack up engine technique, and also removed the steering stabilizer. I did it to check out an engine knock on the front driver side of a 214,000 mile engine. I plastiguaged the #2 rod bearing and it had .002" clearance (within spec.). Engine had low oil pressure, but still adequate. The cause of the knock was a leaking/cracked exhaust valve. The rod journal/bearing still looked good after so many miles, so that's why I believe the bottom end of this engine is strong! Hope this gives you some insight, and good luck!

gohawks

Are there any engine noise experts who want to take a shot at diagnosis over the phone for me on my dime? I would appreciate it and it may give me some serious piece of mind, which would be priceless at the moment. PM me please.

brandontrek

i would like to hear it cause mine has been making a new noise lately in addition to the 3.0 tick....no loss in power but a new noise...and only when i hold the throttle at a certain pressure...about 1/3 of the way down at 2000-2500rpm...