Oil pump gear one tooth off from factory...wtf?
Oil pump gear one tooth off from factory. Plus 64k engine teardown pics!!!
Edit: Found out what caused the problem. Added more pics.
Just as the title says, we found my oil pump gear was off one tooth, as we were doing my 60k service. This engine has not been touched from the factory, so this mistake would of been made at the factory. The engine has 63k on it and runs like a top. Never had an issue, that would point to this.
My question is, has anybody documented this before? I think it's awfully sloppy to have the oil pump gear off one tooth, set by the factory. This means that the balance shafts were out of phase. I NEVER noticed any weird vibrations or noises and never had a problem with oil pressure. Ron took pics of this, so i'll have him send them to me to share with you guys.
And to preempt the obvious questions: The old timing belt had no slack, the tensioner was perfectly fine and all pulleys were in good shape.
Sidenote and kinda OT: We took the head off to swap in some FP beehive springs and ARP headstuds and the cylinder walls look amazing. Still has strong crosshatching with NO cylinder wall scaring and very little side load wear. I was kind of amazed by this, as this engine has been beat on for 63k. The cylinder walls are a perfect brown color and really look great! Pistons looked perfect as well(i.e. zero pitting) I'm pretty happy with the results of my tuning. Seems my method has held up well, through 63k worth of racing, dynoing, launches, street pulls and LOTS of tuning through lots of different setups.
The pics i'm posting up were taken with my phone. They don't do it justice, as you can't really make out the cross hatchings and wear. We're going to take better pics to document. I'll post them up when i get them.
Just as the title says, we found my oil pump gear was off one tooth, as we were doing my 60k service. This engine has not been touched from the factory, so this mistake would of been made at the factory. The engine has 63k on it and runs like a top. Never had an issue, that would point to this.
My question is, has anybody documented this before? I think it's awfully sloppy to have the oil pump gear off one tooth, set by the factory. This means that the balance shafts were out of phase. I NEVER noticed any weird vibrations or noises and never had a problem with oil pressure. Ron took pics of this, so i'll have him send them to me to share with you guys.
And to preempt the obvious questions: The old timing belt had no slack, the tensioner was perfectly fine and all pulleys were in good shape.
Sidenote and kinda OT: We took the head off to swap in some FP beehive springs and ARP headstuds and the cylinder walls look amazing. Still has strong crosshatching with NO cylinder wall scaring and very little side load wear. I was kind of amazed by this, as this engine has been beat on for 63k. The cylinder walls are a perfect brown color and really look great! Pistons looked perfect as well(i.e. zero pitting) I'm pretty happy with the results of my tuning. Seems my method has held up well, through 63k worth of racing, dynoing, launches, street pulls and LOTS of tuning through lots of different setups.
The pics i'm posting up were taken with my phone. They don't do it justice, as you can't really make out the cross hatchings and wear. We're going to take better pics to document. I'll post them up when i get them.
Last edited by iTune; Apr 11, 2010 at 02:16 PM.
I think i figured out what happend. This issue must of happend when i swapped in my new cams, 3 years ago. Everything seems to be fine, so i hope no damage was done. The balance shafts would of been slightly out of phase(only one tooth), so i doubt any harm was done.
lol...true. I'm a tuner not a mechanic...lol. We were in a serious rush as the car had to go back on the dyno asap. I should of QCed the install, but didn't. I trusted the tech's word and went on my way. Bad move. Although, nothing was damaged. So, we're OK this time.
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Update w/ pics
Took some more pics, after Ron cleaned everything up. There is literally ZERO pitting of any kind or any other signs of pre-ignition or a major detonation event on the piston crowns. You can really see the cross hatching in these pics too. The head looked perfect as well. Keep in mind; this stock engine has 64k HARD miles on it. It's been through a lot.
Enjoy!
~Cary
Enjoy!
~Cary
Last edited by iTune; Apr 9, 2010 at 05:27 PM.
Your tensioner might be going bad, or a pulley bearing ****ting the bed. Have you done your 60k service?
Oh yeah, it was off 1 tooth for sure. Are you sure you didn't have the oil drive gear 180 out of phase? This is easy to do, if you aren't careful. When the drive gear is 180* out of phase, your balance belts are too....which will cause bad vibrations. One tooth off for me, was not noticeable at all. It was like this for almost three years.
i was 1 tooth off on mine , unless it was 180 off plus 1 tooth cause i could spin the belt around 3 times and it would go all the normal place but just 1 tooth off where it should of been
Thanks man! I was proud! It just goes to show, semi-aggressive boost levels(with-in the margin of safety) and a conservative tune will still make power yet will prolong engine durability. The methods i use, were taught to me by one of the best in the world. They have proven time and time again, that if you leave a little power on the table, the engine will last a lot longer.
I'm still a firm believer in NOT tuning on the ragged edge. This engine is just more proof of this belief.
Of course, another thing you must take into account is maintenance and what kind of fluids you use. This engine had it's oil changed every 3000 miles(on the dot) during normal use. Changed after every race day and after long days on the dyno. During street tuning, the oil gets changed after 1500 miles. This goes a long way, as you DON'T want blow-by and extreme heat to destroy the oil's capability of doing it's job. There wasn't a drop of sludge buildup in the motor, nor was there any brownish buildup at all. The head was spotless and looked brand new.
I'm still a firm believer in NOT tuning on the ragged edge. This engine is just more proof of this belief.
Of course, another thing you must take into account is maintenance and what kind of fluids you use. This engine had it's oil changed every 3000 miles(on the dot) during normal use. Changed after every race day and after long days on the dyno. During street tuning, the oil gets changed after 1500 miles. This goes a long way, as you DON'T want blow-by and extreme heat to destroy the oil's capability of doing it's job. There wasn't a drop of sludge buildup in the motor, nor was there any brownish buildup at all. The head was spotless and looked brand new.