|
Broken Balance Shaft Belt
So I thought I’d share a story with you, EvoM. Saturday night I was in Orlando (about 4 hours from where I live in Tallahassee) visiting some friends. I was driving my IX hard for a bit, did a launch, and then cooled down by driving to Taco Bell for that $5 cravings deal... lol well lo and behold I pull into the parking lot and notice I have an engine light. Luckily I had my laptop on me and pulled the code with evoscan: P0011 “Variable Valve Timing System” Of course, I Immediately run to the Internet looking for an answer or similar problems. What this lovely forum pointed me towards was possibly a jumped tooth or some sort of issue with the timing belt/cam gears/etc. I cleared the code, but it came back on when I restarted the car. The car, however, idled fine and was drivable, though It was incredibly sluggish above 3500 rpms and boost would come on super slow. After a couple little max-boost test pulls I decided the car was most definitely not right and this was a serious issue that I needed to get fixed ASAP. I headed to my GFs house to spend the night, then left the next day for Tally. Went 70-75 the whole way and hit only 2psi the entire trip (Incredibly I got 24mpgs lol) I get home, relax, and rest. Yesterday I took the car to get looked at because messing with the timing is certainly not something I wanted to do myself, especially not having a garage or many tools at my current residence. Not to mention the car is my DD and I can’t afford to Uber everywhere. Today they finally got around to looking at it... and well I’ll just let the pics speak for themselves.... https://cimg8.ibsrv.net/gimg/www.evo...bc4f0e1a7.jpeg https://cimg9.ibsrv.net/gimg/www.evo...45320d752.jpeg https://cimg0.ibsrv.net/gimg/www.evo...b24eb73e9.jpeg |
As you can see, my balance shaft belt was OBLITERATED. In fact, there was another chunk on the other side of the timing tensioner and it marred the oil pump pulley. Astonishingly, though, it managed to explode and not damage any of the timing components in a catastrophic manner!! I found this incredible and I am very lucky. That would have been it for my motor if it had destroyed that belt. anyways, thought I’d share my great fortune. Should have it back on Th/Fr, so I won’t be able to confirm if all is truly well until then. I’m going to follow up with a compression test, but I doubt any harm could have been done considering the timing was spot on and the components were still functional. My only worry is with oil pressure though... Doesn’t the balance shaft belt have some part to play in that system? Not sure, maybe someone can chime in on that |
Originally Posted by captiveis1
(Post 11803726)
Doesn’t the balance shaft belt have some part to play in that system? Not sure, maybe someone can chime in on that[/left]
Not sure why that happened. Looks like you have an aftermarket timing belt? Was the BS belts changed as well? https://cimg9.ibsrv.net/gimg/www.evo...1ba62171bc.jpg |
I’m not sure, all I can say is that the BS belt was a POS lol
Im having them replace a lot of parts in there so I can sleep easy lol -Serpentine Belt -Timing Belt -BS Belt -BS Tensioner -Timing Tensioner -Oil Pump Pulley -Timing Pulley -Lower Timing Cover hopefully she will run better than ever when it’s all done! |
How many miles on the clock?
|
Do your self a favor and don't bother putting another balance shaft belt in. skip to 7:45 to see my advice on the rear shaft.
|
Originally Posted by captiveis1
(Post 11803726)
Doesn’t the balance shaft belt have some part to play in that system? Not sure, maybe someone can chime in on that[/left]
You got lucky once, i would not bother putting that rear balance shaft belt in again if you remove the front shaft as well. |
Originally Posted by MinusPrevious
(Post 11803732)
How many miles on the clock?
|
Originally Posted by DontStopMe
(Post 11803734)
Not the rear balance shaft. Only the front shaft drives the oil pump and that shaft is ran directly off the timing belt.
You got lucky once, i would not bother putting that rear balance shaft in again. |
This generally happens when someone neglects to change the BS belt when doing a tbelt service. Be sure they replace the hydraulic tbelt tensioner too, not just the pulley.
|
You don't need to delete it. Just don't put the belt on, no harm in it. I ran my car like that for a while, no issues, just a hair more vibration.
|
Originally Posted by DontStopMe
(Post 11803734)
Not the rear balance shaft. Only the front shaft drives the oil pump and that shaft is ran directly off the timing belt.
You got lucky once, i would not bother putting that rear balance shaft in again. Are the two Balance Shafts working together to reduce vibrations for the same RPM range or different ? Example , rear shaft reduces vibrations only “A” rpm range and front reduces for “B” rpm range. Not where both are working together for the same range... So if removing just that rear balance shaft will that allow more , less or non vibrations felt compared to removing both front and rear ? Thanks for your Boosted Film videos, I like the VLOG’s and howto’s you made/share with us. |
There's always someone who swims upstream. I recently did my 120K timing belt service and went without the balance shaft belt. I didn't like how the engine responded to this change and put a belt back on. It was loud at higher rpms.
Yes, the balance shafts work together and at the same rpms. They're used in an attempt to correct what is called a second order vibration that all inline fours have. I'm not saying I understand this but the explanation is that the pistons going down undergo a different acceleration than the pistons going up. My experience is that the balance shaft belt, having no tensioner, can be pretty loose after 60K of use and I am now in the habit of going in and retensioning this belt after 30K. |
Originally Posted by captiveis1
(Post 11803741)
Yeah, I played with the idea and read a couple threads on why to/how to delete it... but it just wasn’t feasible for me at the moment. I needed the car ASAP and couldn’t wait for extra parts to come in to complete the delete. In the future when I build the motor though, I will definitely be removing it
Originally Posted by barneyb
(Post 11803758)
There's always someone who swims upstream. I recently did my 120K timing belt service and went without the balance shaft belt. I didn't like how the engine responded to this change and put a belt back on. It was loud at higher rpms.
Originally Posted by barneyb
(Post 11803758)
My experience is that the balance shaft belt, having no tensioner, can be pretty loose after 60K of use and I am now in the habit of going in and retensioning this belt after 30K.
|
Originally Posted by barneyb
(Post 11803758)
There's always someone who swims upstream. I recently did my 120K timing belt service and went without the balance shaft belt. I didn't like how the engine responded to this change and put a belt back on. It was loud at higher rpms.
Yes, the balance shafts work together and at the same rpms. They're used in an attempt to correct what is called a second order vibration that all inline fours have. I'm not saying I understand this but the explanation is that the pistons going down undergo a different acceleration than the pistons going up. My experience is that the balance shaft belt, having no tensioner, can be pretty loose after 60K of use and I am now in the habit of going in and retensioning this belt after 30K. I would be concerned about the fretting damage that is likely occurring. If youre sensing vibration running w/no BS's, imagine the fretting damage that is occurring :crap: If youve built a hard core race engine that has a short lifespan, I would say OK & leave off the BS's. But if youre trying to maximize your engine life or have a built motor & want it to last, consider leaving the shafts in |
| All times are GMT -7. The time now is 10:39 AM. |
© 2024 MH Sub I, LLC dba Internet Brands