HELP GUYS! VERY odd mechanical 3.5 swap problem!
10-25-2006, 03:37 PM
#1
HELP GUYS! VERY odd mechanical 3.5 swap problem!
Hey guys...I posted a thread recently, saying that my engine began whining (more loudly as the engine was/is revved). I drove the car for 1,500 miles w/o incident/noise and then, suddenly, the noise began appearing. It was/is clearly a mechanical metal-on-metal sound and it became louder each day.
Anyway, I finally decided to take the car to a local import-specialist to have them check it out. By the time I arrived, it was really, really loud. BTW, I should say that I had eliminated any exterior causes (belt tensioner, alt, ps pump, A/C comp, etc.) prior to bringing it to them.
Update: they pulled the outer timing cover off today and found that THE CHAIN TENSIONER FOR THE SECONDARY (CAM) CHAIN ON THE FRONT BANK HAD BEEN GROUND DOWN, THROUGH THE PLASTIC COATING, TO BARE METAL!!!). This was the metal-on-metal sound I'd been hearing. It got worse as the plastic coating began wearing off. Everything in the timing area (aside from this) looks great...NOT oil-starved or anything.
A little background...I used the 3.0 timing gear (WITH THE 3.5 SECONDARY TENSIONERS...ANOTHER ORG'ER SAID IT WOULD BE FINE TO DO SO), 3.0 upper and lower oil pans. Lastly, CAM ADAPTERS FROM STEPHENMAX WERE USED.
Obviously, I need a new tensioner, BUT I'm/we're trying to discern what, exactly, caused this to happen so that it doesn't happen again. The rear bank looks absolutely perfect, BTW.
Any ideas, fellas? Thx in advance. Steve.
Anyway, I finally decided to take the car to a local import-specialist to have them check it out. By the time I arrived, it was really, really loud. BTW, I should say that I had eliminated any exterior causes (belt tensioner, alt, ps pump, A/C comp, etc.) prior to bringing it to them.
Update: they pulled the outer timing cover off today and found that THE CHAIN TENSIONER FOR THE SECONDARY (CAM) CHAIN ON THE FRONT BANK HAD BEEN GROUND DOWN, THROUGH THE PLASTIC COATING, TO BARE METAL!!!). This was the metal-on-metal sound I'd been hearing. It got worse as the plastic coating began wearing off. Everything in the timing area (aside from this) looks great...NOT oil-starved or anything.
A little background...I used the 3.0 timing gear (WITH THE 3.5 SECONDARY TENSIONERS...ANOTHER ORG'ER SAID IT WOULD BE FINE TO DO SO), 3.0 upper and lower oil pans. Lastly, CAM ADAPTERS FROM STEPHENMAX WERE USED.
Obviously, I need a new tensioner, BUT I'm/we're trying to discern what, exactly, caused this to happen so that it doesn't happen again. The rear bank looks absolutely perfect, BTW.
Any ideas, fellas? Thx in advance. Steve.
10-25-2006, 08:35 PM
#2
The only thing I can think of is that the tensioner was somehow not getting oil. I've been running the 3.5 tensioners for over 6k miles now, and everything is fine. Every 3.5 swap has used the 3.5 tensioners IIRC.
10-25-2006, 08:47 PM
#3
Originally Posted by GoalieKeg
Every 3.5 swap has used the 3.5 tensioners IIRC.
As for your problem, I would buy all new equipment and reinstall it.
10-25-2006, 10:33 PM
#4
Originally Posted by Stabone
Probably true, although I broke one of the plastic pieces so I put one of the 3.0's plungers in place and works great.
As for your problem, I would buy all new equipment and reinstall it.
As for your problem, I would buy all new equipment and reinstall it.
10-26-2006, 06:28 AM
#5
Originally Posted by GoalieKeg
The only thing I can think of is that the tensioner was somehow not getting oil. I've been running the 3.5 tensioners for over 6k miles now, and everything is fine. Every 3.5 swap has used the 3.5 tensioners IIRC.
10-26-2006, 07:53 AM
#6
If the tensioner was starved of oil, wouldn't that mean that there would be a lack of tension? How would accelerated wear be caused by less tension??
BTW, I used the 3.5 2ndary tensioners for my swap, and never had any problems .
BTW, I used the 3.5 2ndary tensioners for my swap, and never had any problems .
10-26-2006, 07:56 AM
#7
Another update, guys. The shop called and said they'd removed the secondary chain tensioner and the piston part of it that slides up and down was damaged (as was the plastic coated guide on top). Everything else in the case looks perfect. They can't tell, at this point, what caused this as the other tensioner appears to be just fine. HOW IS THE OIL PRESSURE TO THESE TWO TENSIONERS CONTROLLED? The mechanic was wondering if it's controlled by the VTC solenoids (which, of course, aren't being used). SHOULD I REPLACE BOTH 3.5 TENSIONERS WITH 3.0 TENSIONERS OR ???. What else should we be sure to look for? They are going to be checking this thread (and possibly posting on my behalf) later today. Thx much for the responses. Steve.
10-26-2006, 07:56 AM
#8
EDIT: How was it damaged? If there was a lack of oil getting to it I can see how the piston would be damaged.
The VTC's wouldn't have anything to do with it since you are still using the 3.0 timing cases.
The oil pressure from what I understand is built up from the oil pump and is transferred to the tensioner in passages through the cylinder head.
The VTC's wouldn't have anything to do with it since you are still using the 3.0 timing cases.
The oil pressure from what I understand is built up from the oil pump and is transferred to the tensioner in passages through the cylinder head.
10-26-2006, 08:31 AM
#9
How was it damaged? I/we have no idea. I've never had the block or heads apart...only the upper/lower oil pans and timing assembly. In addition, I followed the FSM re: RTV sealant applications precisely. Now, with that said, I should mention that I, like many others, have experienced cold-startup clatter since day one. The clatter ALWAYS goes away (as does the oil light) within 1 second and warm-startup is just fine. Some say this noise is normal and others say they don't experience it at all. I'm at a loss and I don't want them to reassemble anything b4 I've/we've taken all necessary steps to prevent this from happening again.
10-26-2006, 08:42 AM
#10
^ I think part of that cold start chatter is because oil feels thicker when cold and might take a second longer for it to start flowing. I can see how synthetic oil might not have this problem. But then again, I don't know if the guys not having this problem are using synthetic or not. Personally I used regular 5w30, and did experience the slight clatter at startup but like yours it went away within a second.
10-26-2006, 09:53 AM
#11
Yeah...it hasn't mattered which oil (or filter, for that matter) I've used (currently Mobil 1)...I've always heard the exact same clatter. Anyway, what would be the best way to check the flow of oil to the tensioner(s)?
10-26-2006, 11:24 AM
#12
Strange. I guess I'm one of the few that does not have this clatter issue. I have absolutely no noise on startup, and I use 10w-30 dino oil. Even with colder temps in the morning I have not seen any change.
10-26-2006, 02:02 PM
#13
It seems to me that the tensioner was installed incorrectly it could have been crooked that's all it takes and you might think it's installed right but the spring/piston is not seated correctly. It's not common but really easy to get one of those springs/piston stuck. I think in this case since your mechanic noticed no oil interference. That would
be my assumption, their's not much going on with a tensioner it just rides up and down from a preloaded spring. Take one more look at that tensioner and see why it failed. Other than that reinstall with new parts cross fingers and start her up.
Another suggeston make sure all the tensioners work properly with oil. Sometimes especially after a timing cover removal and installation you must pay close attention to the oil passage ways. Sometimes you may not notice some debris from rtv metal shavings etc. could clog up some critical areas and cause damage to the piston. Remember that piston moves pretty fast . If you look at the tensioner their's a small hole that allows oil to run through the upper portion of the head. I normally run a shop air making sure all debris are clear.
Good Luck
be my assumption, their's not much going on with a tensioner it just rides up and down from a preloaded spring. Take one more look at that tensioner and see why it failed. Other than that reinstall with new parts cross fingers and start her up.
Another suggeston make sure all the tensioners work properly with oil. Sometimes especially after a timing cover removal and installation you must pay close attention to the oil passage ways. Sometimes you may not notice some debris from rtv metal shavings etc. could clog up some critical areas and cause damage to the piston. Remember that piston moves pretty fast . If you look at the tensioner their's a small hole that allows oil to run through the upper portion of the head. I normally run a shop air making sure all debris are clear.
Good Luck
10-26-2006, 02:14 PM
#14
Originally Posted by Nismo3112
If the tensioner was starved of oil, wouldn't that mean that there would be a lack of tension? How would accelerated wear be caused by less tension??
BTW, I used the 3.5 2ndary tensioners for my swap, and never had any problems .
BTW, I used the 3.5 2ndary tensioners for my swap, and never had any problems .
Easy, because these tensioners are constantly riding on the chain depending on the engine load the tensioners with oil or no oil is going to provide a load even in the down position. Like in this case as rev increased noise increased >(chain tightens up)
10-26-2006, 03:18 PM
#15
Another update. The shop called me. They're replacing the tensioner and the secondary chain (just in case). They pulled off the VTC solenoid assembly as well and have discovered no blockages, etc. They're going to give me a 12 mo./12K mile warranty on the parts and labor, which is great (as I'm certain the problem would reappear by then if it ever does at all). I guess we'll see. I really can't think of anything else they should look at as they said everything looks like new inside.
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