im running a t3/t4 50 trim on 8 psi on a stock d16y7 w/ crome chipped ecu. i was driving around and everything was going great until i saw that my oil pressure was running low on my gauge, like around 5psi and below.

i drove back home to check it out and came to find that i had barely any oil in the motor. i heard knocking when running during low r's (2-3k), but it doesn't knock when its idling. some guys told me id probably have to replace my rod bearings, some told me the crank may be f*cked..

what are some other possible symptoms? what else may have been damaged ? any suggestions on how much boost can a daily driven stock y7 handle? where should my oil pressure be at? what would i need in order to fix this problem? any other suggestions?

id appreciate the help


Modified by ek_bape at 8:53 AM 5/16/2007

 

At higher RPM's does the knocking get louder and faster? Its hard to say since your saying at idle you can't hear it. hmmm maybe a sound clip would help determine your problem!

 

Dont run the motor at all until you figured out the problem. If you caught it early enough, you wont have any major damage. Pull the oil pan and look for metal shavings, that will tell you if you have bearing issues.

 

Best thing is to change the rod bearings. Or if possible rebuild the block. But dont drive it. It will break a hole in the block.

 

Once it had knocked already the bearings are probably spun.......

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mighty137 &raquo;</TD></TR><TR><TD CLASS="quote">Once it had knocked already the bearings are probably spun.......</TD></TR></TABLE>

Great Observation(sarcastic voice)! But there saying if its knocking don't continue to drive it and really do some serious damage when the rod gives and go's through his block OR he will expletive the crankshaft up. If he catches it in time he could hope to simply swap bearings and be good to go.


Modified by SD_Lurker at 11:37 AM 5/16/2007

 

absolutely not true. there is a point where you can have bearing damage but its not bad enough to spin in the tunnel.

 

the knocking gets louder at higher rpms. i haven't drove it since the problem occurred and will not until we find out whats wrong. but i did however, see metal shavings mixed in the oil when i looked at the dipstick. anything else i should be aware of?


Modified by ek_bape at 8:52 AM 5/16/2007

 

Knocking will sometimes go away during idle once the motor is warm. But if you rev it at all, you'll hear that non-consistent hammer-on-hickory sound.

Be aware that your pump may be screwed from the oil shavings. Anything smaller than the pickup's screen will go through the oil pump gear, only being caught in the oil filter after the pump.

One thing I've noticed on Y7's is that their crank isn't crossdrilled. Only one side of the journal gets oil, which spreads around the journal. Meaning the death cycle on Y7's is faster than you'd expect.

You'll also want to inspect the mains. The user here K_motor sold me a bad Y7 block that not only had 3 spun rod bearings, but 2 *mains* were spun. It seems impossible, but somehow he did it, then sold it to me w/o saying a thing.

 

hope u know any thing about machnics. You can start pulling the head off and dont mind putting the oil pan back on. When u take it apart u will be able to spin the crank and u can push down on the pistons one of them will move the one or 2 that move thats ur problem. Just get new oem rod bearings and take one rod out and replace it one by one. OR find some one that can do it for u. I have d15 and the 2# piston rod bearing is bad might use it to build a all motor 15 later it allso nocks and wont start over when it was in the car.

 

we figured it was piston #2 that was knocking but im ordering a new set of rod bearings and mains from a machine shop sometime this week. hopefully this will fix it for now until i can afford another single cam.


Modified by ek_bape at 5:45 PM 5/16/2007

 

make sure u get the oem size not the thicker size bearings If you crank is stock.

 

borrow some slicks, put a couple gallons of c16 in it, crank the boost to like 16 and go for a hail mary 11 sec pass.

 

my buddy told me the bearings could possibly be welded to the pistons? im hoping the new bearings will do the job until i can get another block. i also ordered a set of arp head studs to go along with the setup. anyone have any good reviews on those?

 

i have seen y8's with less than 100k for like $400, those head studs are worth like 100 right? I think you are taking the wrong approach to this.

 

i haven't made any purchases yet, but the motor is getting ripped apart as we speak. i wonder how long it would run after we get it fixed.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by oneludesol &raquo;</TD></TR><TR><TD CLASS="quote">borrow some slicks, put a couple gallons of c16 in it, crank the boost to like 16 and go for a hail mary 11 sec pass.</TD></TR></TABLE>

I think this is your best shot.

The bearing is spun, motor is trash. Get another one and cut your losses.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ek_bape &raquo;</TD></TR><TR><TD CLASS="quote">my buddy told me the bearings could possibly be welded to the pistons? im hoping the new bearings will do the job until i can get another block. i also ordered a set of arp head studs to go along with the setup. anyone have any good reviews on those?</TD></TR></TABLE>I pretty sure this could never ever ever happen.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tony1 &raquo;</TD></TR><TR><TD CLASS="quote">

I think this is your best shot.

The bearing is spun, motor is trash. Get another one and cut your losses.</TD></TR></TABLE>

I think he should boost atleast 20lbs to make it worth it...the 60ft should be nuts if it hooks.....

 

hahah yea i was thinking about it but i think this ban aid fix just might hold up till i get another block.

 

Dont give up, only spun main bearings will trash your block. Over the years Ive spun 1 rod bearing and trashed another rod bearing (didnt get bad enough to spin) on the same motor. I was able rebuild it each time. Most likely you'll need a new crank, possibly a new rod. Good luck.

 

great observation! u rock muckman.

 

Yeah, I just did the EXACT SAME THING to my motor (and I've learned that engines run much better when they've got oil in them ) What can I say- I'm an idiot. But yeah, when mine spun that bearing, I could see that it screwed-up my crank, but I didn't think it was that bad (I guess you only see what you want to, or DON'T want to). So I tried rubbing it out with some emery paper and installed some new bearings. So I drove it 10 or so miles away from my house to start breaking it in- and sure enough, my crank was worse that I thought, and it chewed through that bearing by the time I got back to my house. So I've learned that when working on your car, Murphy's law is always there to bite you on the ***, and as bad as you think it is, its probably worse. I've had to pull my motor, buy a new crank, and this has been more of a headache than I had ever anticipated. Don't try and find the easy

 

Yeah, I just did the EXACT SAME THING to my motor (and I've learned that engines run much better when they've got oil in them ) What can I say- I'm an idiot. But yeah, when mine spun that bearing, I could see that it screwed-up my crank, but I didn't think it was that bad (I guess you only see what you want to, or DON'T want to). So I tried rubbing it out with some emery paper and installed some new bearings. So I drove it 10 or so miles away from my house to start breaking it in- and sure enough, my crank was worse that I thought, and it chewed through that bearing by the time I got back to my house. So I've learned that when working on your car, Murphy's law is always there to bite you on the ***, and as bad as you think it is, its probably worse. I've had to pull my motor, buy a new crank, and this has been more of a headache than I had ever anticipated. Don't try and go with the easy way out, because that will NOT fix your problem.

 

well we found out that the mains were ok but bearings 2 and 3 were fried. we came to the conclusion that it IS fixable. a new bearing set will run a good $60 at the local machine shop and i also just picked up a stock rebalanced crank for $70. it should be good to go soon.