Aaron92SE

iTrader: (128)

I need an exact measurement of how tall the old VTC spring is. The more measurements I can get from different used springs, the better.

The new VTC spring in the rebuild kit should be taller and stiffer than the old spring. When I rebuilt my VTCs a couple years ago, the ticking returned within 1,000 miles. The spring in the rebuild kit was the same height and stiffness as the springs that came out of my car.

I am about to order a new VTC rebuild kit and I want to make sure the new kit has a taller spring this time.

Thanks!

Cliff Clavin

iTrader: (11)

where are you ordering the kit from and how much is it?

my local dealership is a bunch of retards.

Jeff92se

iTrader: (82)

You clean the oil gallies too? As I think inadequate oil supply/pressure might cause the dreaded tick also.

Aaron92SE

iTrader: (128)

The TSB says I have to remove the heads in order to clean them. But no, I didn't clean them. This time, I will try my best to clean them without removing the heads.

You got any tips?

Cliff Clavin, Courtesy is where I got my last kit. But I am reluctant to order from them again since they keep messing up my order. I have changed to Dave Burnette at Southpoint Nissan. I think the kit is around $25 each. You need two of them.

Anybody got an old VTC spring laying around that they can measure for me?

Michael

iTrader: (21)

remember when you brought this up that I told you the springs on the rebuild kit I put on PA's car were exactly like the ones that came out. I thought it was strange too because Mike had mentioned how his were taller and stiffer.

His car still isnt ticking (well last I saw it anyway) after 2 years so I dont think its the spring that is the problem but maybe something you did or the oil galleys are restricted.

BTW the kit I put on my current car were longer and stiffer.

My theory (and I mentioned this last time you brought it up as well) is that those are old springs and the post 94 springs are the ones that are longer and stiffer.

xx-Marshall-xx

iTrader: (15)

South Point Nissan DOES sell VTC rebuild kits
but he quoted me $29.50 for them lol

but im definitely going to order them

Dave told me
"The parts number isnt in the system, so when you have a new guy he has no idea what your talking about"
^ everyone i try to talk to does this to me

Matt93SE

iTrader: (44)

Aaron,
I've got a set of VTCs in the garage that I was going to send in and have them keyed to make my cams adjustable. once they came back, I was going to rebuild them w/ new springs.

you want me to pull one apart and measure the spring?

Matt93SE

iTrader: (44)

that's cheap. I paid $35 each for them about 4 years ago and they've been sitting in my garage until June this year.

MrGone

iTrader: (30)

MyGreenMax94 has my old ones, he'll probably be by soon.


From what I remember there really wasn't much of a difference between 143k/165k mile springs vs new ones. I didn't really do much in the way of accurately measuring them but doing a simple side by side comparison, I would have been hard pressed to guess which ones were used vs. new if I didn't know any better (aside from the oil and small indications of use)

Check for grooves on the base of the VTC assembly. I also wish they included new oil rings inside the kit.

I was thinking about what would happen if you were to weld the spring to each side of the assembly but aside from being next to impossible to do (and undo), it would also change the forces on the spring and a whole other can of worms. Then I thought about what if you were to tack the spring to the base because the spring does move around a bit (you'll probably notice some wear, probably even some grooves)

Indexing the spring is a freebie, it may make the difference between 1000 miles and 200,000 miles, or it may not make a difference at all (depends how much the spring rotates/twists inside the assembly). When I say indexing I am referring to installing the spring against the direction the base and middle section rotate when the VTC advances.

I think making a small spacer to put on the base could be promising. Again it's going back to the wear I noticed on the base (I can only assume there is some wear in the inside part of the middle section but it's difficult to tell because of the design). A spacer would also increase the spring rate (unless it is thick enough to replace lost material from wear). I would be cautious about changing the spring rate, it's playing with fire. (FWIW I think it could stand to be increased slightly but have not done the math to support it).

I haven't ruled out the possibility of the middle section of the VTC contributing to the problem. The noise occurs when the middle section slams into the cap (hence the caps breaking on some cars...awsm66 has good luck finding these cars lol). The middle section is is not a solid piece like the base, cap, and outer housing, it rotates ever so slightly. Since I have not disassembled one yet I cannot be certain that it does not contribute to the problem. Ultimately the reason the middle section snaps back is the spring is unable to counter the forces between the rotation of the camshaft and the valve train.

MrGone

iTrader: (30)

Also consider that metal at engine operating temperatures has different characteristics than at room temp.

You guys who have ever had VTC noise will probably notice that when the engine is cold the VTCs perform as they should but once it warms up clack clack clack (on ungrounded cars with intermittent noise that is. It all depends on the condition of the springs/VTCs and other factors (*cough* oil)).


I'm interested in how rebuilt assemblies are holding up for other people:
How many total miles on the engine?
How many miles did you have on the factory VTC springs before they made noise?
How many miles do you have on the new springs?
Have they made any noise since you rebuilt them?
etc.

I'm curious if Nissan improved the spring in the rebuild kits or if it's the same as new and essentially a consumable. It would be nice if they did improve the spring to make it more resistant to fatigue.

(If the springs are improved, which I don't believe they are, maybe you somehow got new old stock, but in that case they couldn't be the rebuild kits. Besides factory springs lasted longer than 1000miles. My money is on either your assemblies are worn out (lowering the spring rate) or you got used springs (maybe an employee switched them, maybe someone returned them and the parts guys were none the wiser, etc).

Aaron92SE

iTrader: (128)

If it's not any trouble, then yeah, I like a measurement of exactly how tall they are.

But like Mike said, his weren't taller and they worked fine. That's why I don't want you to go through too much trouble measuring the spring for me. If you aren't ready to do the VTC rebuild on those sprockets, then don't worry about it.

Thanks for your help. It's SLIGHTLY possible that I got a bad spring. 1K is a new one. I bet you could imagine how mad I was when I heard my motor tick only a couple weeks later!

I am going to try to order another one from Courtesy and hopefully make sure I get the taller spring that they have. But in order to make sure it's taller, I need to know the height of the stock spring. I don't want to have to dig into my parts car motor. I'd like to keep that somewhat together in case I need that motor someday. I am hoping someone has this spring laying in a parts bin somewhere. I threw mine away when I did the job initially.

I would be more inclined to believe that my VTC sprocket assemblies might be worn down excessively. But I didn't inpsect them and they looked BRAND new visually. There were no wear marks wheren the spring sits. And I replaced the cap with the cap that came with the kit.

And it's very possible that the gallies are so clogged that the new springs overheated within 1K miles and weakened just enough to tick. In fact, I noticed that when the ticking returned, it DEFINITELY got louder than it ever was with the older springs. So when the ticking came back, it got louder than the old setup in less than 3K after the rebuild. It's still getting louder every month.

I am finally drawing the line and going to rebuild them. While I'm in there, I might as well replace the guides and tensioners for fun. Any other things I might need to change or look into?

I hope I can clean the gallies with a tiny pipe cleaner. I bought the car with 97K miles on it and it's always had proper oil change intervals. But who knows how it was abused before I got it!

Jeff92se

iTrader: (82)

Actually when the VTCs get real bad, the clack all the time, warm or cold.

Aaron92SE

iTrader: (128)

Jeff, you must have missed my little question. Do you have any tips on cleaning the oil gallies without removing the heads?

I know you have been known to do a lot of stuff without removing your heads. Like rethread a spark plug hole!

Jeff92se

iTrader: (82)

I get a ghetto clean. I found a length of wire and shoved up/down the oil gally feeding the VTCs (and prayed it didn't break inside the head!)

That worked out very, very well!

Greeny

iTrader: (43)

I can't find them MrGone..

Aaron92SE

iTrader: (128)

Just a normal 18-21ga type wire? Did you notice any metal shavings or gunk come out? The TSB says if you are able to see material come out, then you have to remove the heads, which I won't do! If I go that far, I might as well rebuild the motor!

Jeff92se

iTrader: (82)

Whatever wire fit in there yes. But I did have the luxury of having the engine out as I was doing a clutch/flywheel vtcs, studs, water pump blah, blah..... I think I also did a headgasket on that first engine too.

Aaron92SE

iTrader: (128)

Thanks man! So you didn't see any material come out? Just clean oil residue?

Greeny

iTrader: (43)

Alright,since all you ******* are in here ,My vtc's ungrounded will cause a severe loss of power in the lower rpm band [until about 3600 rpm] when warm,then the thing will take off like bat out of hell after approx 3600 rpm.

I know everyone says knock sensor,but mine has been bypassed for years,it makes no difference at all with or without the 470k resistor in there..

But when i ground the vtc's the power loss goes away???


Thoughts??

Aaron92SE

iTrader: (128)

The VTCs are designed to help low end power. When you ground them, it makes it so they don't release in order to get your top end power back.

Maybe a completely bad VTC system could hurt low end power. Once it's grounded, it FORCES the VTC to work. So maybe the VTC solenoids don't like you.

Jeff92se

iTrader: (82)

Not that I remember. But that motor was a sludge fest. Varnished up like a mother. But I didn't notice anything like "whoa!" on the wire. I think I pushed it down though the top and up though the oil jet under the chain tensioner (I think)

Aaron92SE

iTrader: (128)

Cool. Thanks Jeff. The VTC topic is always a fun subject to talk about on the org.

Greeny

iTrader: (43)

Well my vtc's were rebuilt at 140k by the previous owner.[now at 306k]

They clack intermittently when grounded,always have..I replaced the selonoids...Still the same thing..

Aaron92SE

iTrader: (128)

You got me too. It certainly sounds like a KS to me. Sorry, I just had to say it.

If they clack when grounded, gallies could be clogged preventing the solenoids from providing the correct pressure needed.

But you know it's time for another rebuild or this time, replacement. $$$$ I'm sure you can rebuild 300K mile old VTCs and not have a problem. It all depends how they look inside. Make sure they aren't scard up badly.

Greeny

iTrader: (43)

Yeah,it does sound like a k/s issue but it is not,trust me i have tested this problem over and over/through and through...It is the vtc's...

Meh,she's close to new engine time anyhoo...

Aaron92SE

iTrader: (128)

That's right! Drop a new motor in that thing.

Greeny

iTrader: (43)

New to me anyway..

I have one on hold at a local yard for $400..With 110k on it..i just need my intake manifold,the replacement is from an automatic maxima..

Gunther

Huh? I thought VTC noise was more prominent when cold? My car clacks for the first few minutes its running, and I thought it was VTC, is it really lifter tick? I don't really know the difference between the two aside that they sound alike. [I think...]

Aaron92SE

iTrader: (128)

VTC ticking is different for every VE I've seen.

For me, in the morning, the VTCs never tick when cold. At initial startup, I might here some top end rattle due to the oil completely draining to the pan. But, the VTCs don't tick until the coolant temp gets to exactly 165 degrees.

Sometimes, when I drive the car, the VTCs won't tick. I shut the car down to run into the store. Come back and start it, it ticks 100% from then on!

For some people, the VTCs tick when cold and go away sometimes after it warms up.

But to be sure it's not lifters or any other problem, then you can ground your VTCs. See if that ticking goes away, if it does, then it's the VTCs. If it doesn't go away as soon as you ground them, then it's something else like timing chain tensioners or lifters.

Josh

iTrader: (5)

I will measure mine later tonight when I get home until then here is the difference between old an new.

http://web.ics.purdue.edu/~jtdubach/.../P3174266.html

Aaron92SE

iTrader: (128)

Thank you! I was trying to find that picture and I couldn't remember who posted it!

Please take a height measurement of the old springs. That would allow me to make sure I'm getting the taller/stiffer spring.

Could you easily tell that the new spring was stiffer?

For me, they both felt identical! And they were the exact same height.

todamax

iTrader: (6)

When I did mine last summer, the spring I took out were the same size as the ones I put in. BUT, the vtc's had been rebuilt improperly once before. The o-ring and spacer were in the wrong order and one VTC was locked up, I never did get it apart.

I have to rant, as this still pisses me off. I bought the car with 59K on it and it was otherwise pristine. Some knuckle dragger that can't follow a TSB shouldn't have had his digits on the inside of the car. The timing was even off because of the job...


Anyway, the point about the one spring I took out being the same size as the ones I put in might not be valid, as I would assume the spring came from one of those rebuild kits. With the poor assembly method the spring itself might have still been good. Which brings me to the thought of, "why am I bothering to post this info?" I think its because I'm still at work after 12 hours, babysitting a dead Cisco Unity box... TAC and/or HP better call me soon.

505max94se

iTrader: (15)

I think that I'm going to end up buying an MSD RPM switch to control my VTC's. I'll set it up to send ground from idle to rouphly 3500 rpm.

Aaron92SE

iTrader: (128)

It takes a second for the oil pressure to change the state of the VTCs once the solenoids are grounded.

If you set the VTCs to be grounded below 2000, then that might be ok since it will only be grounded while cruising through a parking lot or at a stoplight.

But instead of going through that trouble and having it ground/unground every 2 seconds, just wire a normal switch to ground them. When you enter a parking lot, ground them if you are that embarassed.

I admit, it embarasses me. While leaving a parking lot at a parts store, a guy in the parking lot was staring at my car and I overheard him say "is that a diesel?".

If someone ever mentions my ticking to me to talk down, I simply ask them to meet me at the track and lets see who's motor is stronger!

Gunther

Thanks for the info Aaron. I've been thinking about wiring my VTC's to a switch but it'll have to wait until its a little warmer out. For now I'll drive her easy

Josh

iTrader: (5)

ok, 2.585" for one and 2.611" for the other. And when I replaced them I remember being able to tell a dramatic difference between the old and new as far at their compression strength. Let me know if you need anything else.

Josh

iTrader: (5)

oh yeah, I have about 15k+ miles on these without any ticking and I didn't clean my oil gallies either.

Aaron92SE

iTrader: (128)

THANK YOU! That helps me a LOT!

According to your pictures, the height of the new spring looks to be over 1/4" taller than the old spring. That's a huge difference! Does that sound about right? .25"?

Thank you for those measurements! That's one I thing I love doing is taking very precise measurements.

Josh

iTrader: (5)

Yeah, I would say they were over 1/4" taller. I think they are totaly different spings also, maybe I am wrong but I think the new ones may have been thicker gauge.

Aaron92SE

iTrader: (128)

In your pictures, it looks like they are a thicker spring.

It's such a huge difference compared to what I got. There MUST be a VTC rebuild kit that superceded another! I certainly got the older kit.

Do you have a Cali spec 1992 Maxima?