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2001 Impreza 2.5rs coupe
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Discussion Starter · #1 · (Edited)
Little bit of lead in...

Spun a bearing. Had machine work done by reputable shop that does a lot of subies. Had custom pistons made that at 11.2:1 pistons are ceramic and moly coated.

I assembeled it with full oem gasket set and new oil pump.
I didnt prime the oil pump because i didnt know that i could but i filled the oil filter with oil. Assembly lube was used generously(clevite) and brad penn break in oil used.

First start went great. No problems immedately got oil psi. Let it warm up all was well so i went to bed (it was 2am). The next day i drove it 3 miles to meijer came out started it and it sounded funny. I pulled out of the spot, it lurched and the oil light came on. I killed it immedately and towed it home. Pulled the oil pump and the relief valve is stuck open. I pulled it apart, deburred everything put back together with assy lube (in gears too) started and all was well.

Drove around, no problems. Went to drive an hour away and after 20min on the highway stopped for 7/11. Came out. Started and no oil psi. My friend hit the pump while i started it nd we got pressure. Drove back home, pulled the pump and again relief valve stuck open.

Decided to put my old pump back on( it never had problems). Thuroughly cleaned it and lubed. Didnt check clearances though. Started it and had good oil pressure after aprox 1.5 seconds. Drove 10miles to the store then back and no problems. Next morning drove my roommate to work and again it took 1.5seconds to get psi. I didnt think much of it just thought oil pump might be out of tolerance and will need to be replaced.

Started driving to another place an hour away and while on the highway it started sounding tickey so we pulled over and as we did it sounded clackey and died.

Towed home. Checked timing. Its good. Pulled the motor, drained the oil. Its a bit sparkely but idk how much is too much during break in.

Rotated the motor by hand and theres no noise or binding. Hooked the starter to it and spun it w/o plugs and valve covers. Everything looks and sounds normal. Im at a loss.

My roommate thinks spark knock and there was a misfire code and i think a knock code but im not possitive.

Here is a link to pics of the oil, plugs and a video of it turning. Please, any advice would be greatly appreciated.

2012-01-10_15-48-46_289 - Minus.com

Video of it turning with the starter
 

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2001 Impreza 2.5rs coupe
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Discussion Starter · #2 ·
Pistk. To valve clearance was checked and all bearing tolerances were checked during assembly. Its all good.

The plugs are new denso platnum twin tips. Idk if its too hot for them or something like that. Im not very good at reading plugs. I have put close to 100 miles of breakin on the motor thusfar.
 

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overdeveloped beater
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How many oil changes have you done in this 100miles? If none or just one, that may be (part of) the issue. There could've been an issue with post machine-work cleaning, or assembly issues.

I only run a fresh build for about a few minutes then get that oil and filter out of there. I will then run it for a few miles or 30-60minutes and change the oil and filter again. The 3rd oil change comes about a week later....if the filters come out clean I will change it one more time at 500 miles and go to the normal 3500-5000 mile interval.
 

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95/99 Brighton STi
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were/are you running 93 octane fuel?

I'm not sure running your old oil pump was a good idea also. All it takes is one flake of old bearing material to destroy another bearing.
 

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Discussion Starter · #5 ·
100 miles is the first oil change.

Im confident there arent any old bits of bearing in the old oil pump, I cleaned it obnoxiously.

I had a full tank of midgrade ( i think 91 ) and I was worried about that but it started fine so I ran it and over that 100 miles I added octane booster and stopped twice to top it up with 93 so i could bring the octane rating up.
 

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Discussion Starter · #7 ·
Ok good to know. The impression I had gotten was the assembly lube and a good breakin oil was good for the first 3-500. Ill take that in to consideration the next time around.

Any ideas on the plugs or the possible spark knock?







 

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overdeveloped beater
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If they are just 100 miles old, I'd say they were too hot of a plug. If they've got a few thousand on, they look just about right. Nice chocolate color with no deposits or odd discoloration.
 

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Green 97 OBS
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Do you have an oil pressure gauge? I had this exact problem and it destroyed my bearings. I didn't get the idiot light until the damage had been more than done.

http://www.rs25.com/forums/f13/t160...uild-engine-suddenly-has-no-oil-pressure.html

http://www.rs25.com/forums/f13/t160921-engine-noise-vid-clip.html

The idiot light comes on at 2 psi so if it came on while you were driving, you have no idea how low the pressure got until that point unless you had an oil pressure gauge. I fear for your bottom end.
 

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Green 97 OBS
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Have you tried to start it since you replaced the oil pump? If it got "clacky" as you said, you are done, might as well tear the engine down now. I don't want to be a downer but I unfortunately know that just having it stick once will pretty much ruin the bearings. Even after i fixed the oil pump, and started her up again, the light didn't come on but the engine sounded very loud (at the time I had an open downpipe). I took it to get the downpipe fixed and it was clear to me that the engine was toast.

The oil pressure was extremely low before I decided that a teardown was eminent, at operating temps, the psi sat at about 4 psi @ idle. You can see the light flicker when it idled way down.

Keep in mind, I limped this around the neighborhood. It never was tuned, was running so rich that the spark plugs got shorted by fuel several times, running the engine only on 2 cylinders. I never was able to even drive normally let alone romp on it. It ran for 2 hours from first start to teardown. If you were driving anywhere with it under any load, I expect you're looking at similar damage.

 

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Discussion Starter · #15 ·
dammit this isnt sounding good. The only things that are still giving me hope is my oil didnt look like i had spun a bearing...at least i dont think so.

Also why would it make crazy noise while running and not do it while being turned by the starter? is it because of lack of combustion to push things back and forth harder?
 

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Discussion Starter · #17 · (Edited)
Does this look like oil with 100 miles on it after a rebuild or like oil with a spun bearing?





This one (below) is the only one with significantly large pieces IMHO (bottom right)

 

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Mine never spun bearings, it looked like engine sludge that was slightly metalic. And it also was magnetic from the crank material. Put a magnet in your oil pan like i did and let it sit for a couple hours. If it comes out fuzzy, you have crank material in the oil. I wore out my main bearings, not the rods so it didn't sound like rod knock. That's also why there wasn't 'chunks' of bearing in my oil.


Mine never made noise while being turned over, I primed it many times to make sure there was oil. It was my crank bouncing around in the main journals, and it didn't make a ton of noise until it was running because there was not much force on the crank until combustion occurs and because the engine isn't turning fast enough.
 

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Discussion Starter · #19 ·
Is it just me or is it total bullSh!t that a BRAND NEW OEM oil pump would relief valve issues like this. I'm returning mine and ordered another one from local dealership.

Word of warning...stay away from aftermarket oil pumps. I ordered one from S&G import parts (local parts store) assuming it would be OEM or OEM reman and went to pick it up this morning. It was made by rock oil pumps and it was a POS.

The castings looked sloppy and there was massive play in the gears. I could stick my fingers in the center drive portion and move the gears up and down aprox 1mm and side to side 2-3mm. I told them i didnt want it and ordered one from Hodges subaru.
 
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