Rebuild, not repeat...spun rod bearing
#1
Rebuild, not repeat...spun rod bearing
Oh **** **** **** no no no ahhhggggg ****!!!
Maybe you've been there, maybe you lead a perfect life and haven't. I clearly don't.
I'll try to include all the info I know about what lead to the bearing crush because I see guys getting flamed for not providing info. If you don't want to read all this **** then just look at the shinny pics and speculate away. Or don't.
I am hoping you experienced guys can lead me to the answer so I don't repeat. Thank you in advance.
First the gratuitous pride shot: '02 VVT motor stock internals, BRP kit stock pulleys 8 PSI max, TRDIC, RB header & exhaust, stock ECU, 91 octane.
This all started because the shitty Mazda water pump had a failed bearing at 80k. I tore down the front of the engine and replaced the WP,TB, and seals. While I had it apart I installed a snazzy 5X Racing timing wheel and set it to factory.
Well I fucked up the crank seal install. So because I had left off all the covers I just set the crank @ TDC and clamped the belt to the cam pulleys and pulled the stuff off the crank snout so I wouldn't have to worry about the VC and gasket. I had to do this 3 times After a combo of JB weld and a Redi Sleeve the seal stop gushing. So I put it back together and eyeballed the timing wheel to ~ factory timing. (I had marked the HB for the extremes and center of the wheel's movement)
I went for a fast as hell drive. The car was screaming good and my hard on was enormous. At about 100 miles I got a FLASHING CEL I limped it into a station and checked the oil, let it cool etc. then cruised it to the nearest town with a O'Rielly's and borrowed their scanner ( cool guy there who used to race sports cars at Hallett with his dad) which showed P0012-intake cam too retarded; and P0300-random misfire
I cleared the codes and cruised the car the ~75 miles home with no issues other than the CEL was back within 5 miles.
I pulled it into the garage and checked the timing I honestly don't recall where it was as I received some crappy news and had a few beers that evening.
Next morning I Advanced the wheel about half it's travel and checked timing which showed the left mark @ ~ 5* BTDC 'that's wieird' i thought and proceeded to advance the wheel the remainder of it's +- 6* travel and as I was tightening the HB bolts snapped on off. **** again.
I had family coming later that morning and wanted the car running to show it off. **** you...like you've never done it. So after checking timing again and it being now ~8* BTDC I went for a drive.
I did hear a new racket from the motor and KNEW I should just limp it home but my pride and frustration got the best of me and I revved it to 7k and the #1 rod bearing punished me hard.
As I was pulling the motor apart I found the TB to be loose but had not jumped any teeth.
Question: With 1/2-3/4" play in TB between the wheels can the timing vary without jumping a tooth? And if so would this cause the codes and possible detonation?
All crank journals have some amount of grooving, it is worse at #1 main and progressively better at #5. Did the missing 5.9 gram bolt head throw the crank snout out of balance and cause the high RPM destruction?
OR; Did the crap from the (timing) destroyed rod bearing ooze thru the oil galleys and scour the other journals?
OR; has there been an oiling issue for some time undetected without a proper gauge?
OR; something else? Fresh Mobile1 BTW
PS Vlad (18PSI) is sending me a good crank and rods (of which I plan to use one)
Thanks Vlad!
Maybe you've been there, maybe you lead a perfect life and haven't. I clearly don't.
I'll try to include all the info I know about what lead to the bearing crush because I see guys getting flamed for not providing info. If you don't want to read all this **** then just look at the shinny pics and speculate away. Or don't.
I am hoping you experienced guys can lead me to the answer so I don't repeat. Thank you in advance.
First the gratuitous pride shot: '02 VVT motor stock internals, BRP kit stock pulleys 8 PSI max, TRDIC, RB header & exhaust, stock ECU, 91 octane.
This all started because the shitty Mazda water pump had a failed bearing at 80k. I tore down the front of the engine and replaced the WP,TB, and seals. While I had it apart I installed a snazzy 5X Racing timing wheel and set it to factory.
Well I fucked up the crank seal install. So because I had left off all the covers I just set the crank @ TDC and clamped the belt to the cam pulleys and pulled the stuff off the crank snout so I wouldn't have to worry about the VC and gasket. I had to do this 3 times After a combo of JB weld and a Redi Sleeve the seal stop gushing. So I put it back together and eyeballed the timing wheel to ~ factory timing. (I had marked the HB for the extremes and center of the wheel's movement)
I went for a fast as hell drive. The car was screaming good and my hard on was enormous. At about 100 miles I got a FLASHING CEL I limped it into a station and checked the oil, let it cool etc. then cruised it to the nearest town with a O'Rielly's and borrowed their scanner ( cool guy there who used to race sports cars at Hallett with his dad) which showed P0012-intake cam too retarded; and P0300-random misfire
I cleared the codes and cruised the car the ~75 miles home with no issues other than the CEL was back within 5 miles.
I pulled it into the garage and checked the timing I honestly don't recall where it was as I received some crappy news and had a few beers that evening.
Next morning I Advanced the wheel about half it's travel and checked timing which showed the left mark @ ~ 5* BTDC 'that's wieird' i thought and proceeded to advance the wheel the remainder of it's +- 6* travel and as I was tightening the HB bolts snapped on off. **** again.
I had family coming later that morning and wanted the car running to show it off. **** you...like you've never done it. So after checking timing again and it being now ~8* BTDC I went for a drive.
I did hear a new racket from the motor and KNEW I should just limp it home but my pride and frustration got the best of me and I revved it to 7k and the #1 rod bearing punished me hard.
As I was pulling the motor apart I found the TB to be loose but had not jumped any teeth.
Question: With 1/2-3/4" play in TB between the wheels can the timing vary without jumping a tooth? And if so would this cause the codes and possible detonation?
All crank journals have some amount of grooving, it is worse at #1 main and progressively better at #5. Did the missing 5.9 gram bolt head throw the crank snout out of balance and cause the high RPM destruction?
OR; Did the crap from the (timing) destroyed rod bearing ooze thru the oil galleys and scour the other journals?
OR; has there been an oiling issue for some time undetected without a proper gauge?
OR; something else? Fresh Mobile1 BTW
PS Vlad (18PSI) is sending me a good crank and rods (of which I plan to use one)
Thanks Vlad!
#2
Good start and documentation/pictures.
I honestly don't know what to tell you, its kind of a weird situation. There appears to be scuffing/scoring on your piston skirts and cyl walls, I'd inspect that really closely if I were you. I'd feel really uncomfortable re-using those pistons.
I hope the crank/rods/pump I sent you help out, but I am afraid you might need a full build. Lets hope I'm wrong.
I honestly don't know what to tell you, its kind of a weird situation. There appears to be scuffing/scoring on your piston skirts and cyl walls, I'd inspect that really closely if I were you. I'd feel really uncomfortable re-using those pistons.
I hope the crank/rods/pump I sent you help out, but I am afraid you might need a full build. Lets hope I'm wrong.
#5
There appears to be scuffing/scoring on your piston skirts and cyl walls, I'd inspect that really closely if I were you. I'd feel really uncomfortable re-using those pistons.
I hope the crank/rods/pump I sent you help out, but I am afraid you might need a full build. Lets hope I'm wrong.
I hope the crank/rods/pump I sent you help out, but I am afraid you might need a full build. Lets hope I'm wrong.
THIS is a problem though!!!! E cam bearing with metal shavings presumably from the smashed rod bearing.
I cam bearing...I think the surfaces look ok but I'm not looking forward to pulling the head apart for a solvent bath. I have no idea what I'm doing with this OHC set up.
What say you?
#10
And yes definitely do new rings and hone at a minimum.
#13
So... Oil takes a lot longer to get warm than water - 5 min may not be long enough to warm the oil depending on the local environment (air temp & car speed).
Other factors that may contribute are: using an oil cooler adapter without a thermostat, restrictions due to too small diameter oil cooler lines, too small of an oil cooler, thick oil... (thick oil is likely not an issue here with 5W30)
I suspect the failure scenario goes something like:
- Oil in the pan is cool and thick (ish)
- Oil pump attempts to push oil through - oil cooler adapter, possibly restrictive oil cooler line, cooler, another oil cooler line, oil cooler adapter, then on to the oil filter, and finally to the engine.
- If the resistance at the oil pump is too high going through all the above plumbing, the pressure relief valve located at the pump will open (partly) and dump oil back into the pan. In this scenario, the engine oil volume may be reduced (but may still be high enough pressure at the oil sensor to not be seen as an issue on the NB gauge).
Net effect is borderline oil pressure to keep all the bearings happy. It may be fine on idle or low load but not high RPM or high load or both.
The issue is at high RPM, oil is thrown off the bearings (especially crank) faster than fresh oil arrives. This can lead to oil starvation even though there is lots of oil in the pan, the pump is working fine, etc.
My guess on the cause of failure is too eager a right foot / too much RPM...
#14
Oh and I see oil cooler block in one of the pictures. Does that oil cooler have some sort of a thermostat? If it doesn't even 10-15 minutes might not be enough to warm up the oil. That is most likely your problem. Repeated pulls on the engine over time with cold oil. On a race track it might take 3-4 laps on a cold engine to get the oil temperature up to what the water temperature is. That's 8-10miles of harder driving. Not stop and go around town.
Reading your profile, it says S/C and Nitrous. Was the nitrous used on this run? What are you running as far as management???
#17
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No thermal control on the oil cooler? Ouch.
You probably trashed everything in the VVT mechanism when you filled it full of bearing shards. If you have metal in the cam bearings I would hazard a guess that you probably have metal in the VVT parts as well. Is the little plastic oil filter screen still in place inside the oil control valve?
Your oil cooler is probably also full of metal. Toss it and buy a thermostatically controlled oil cooler kit from someone like Trackspeed. I'm not sure I would be willing to trust the old cooler to actually get clean at this point. The Mocal thermostat used in the TSE kit is pretty much universally accepted by most folks.
You probably trashed everything in the VVT mechanism when you filled it full of bearing shards. If you have metal in the cam bearings I would hazard a guess that you probably have metal in the VVT parts as well. Is the little plastic oil filter screen still in place inside the oil control valve?
Your oil cooler is probably also full of metal. Toss it and buy a thermostatically controlled oil cooler kit from someone like Trackspeed. I'm not sure I would be willing to trust the old cooler to actually get clean at this point. The Mocal thermostat used in the TSE kit is pretty much universally accepted by most folks.
#20
Are you guys serious with the oil temp thing? A trip around the block will heat the oil enough to make it uncomfortable to pull the drain plug and have it on your hand. After 5 min of driving the oil would be very uncomfortable on your hand like putting it under the kitchen faucet turned to hot.
I almost never run my car for 5 minutes before flogging it at an autocross. Never had an oiling issue.
I almost never run my car for 5 minutes before flogging it at an autocross. Never had an oiling issue.