Valve noise after engine rebuild?

[sewebster]

Finally have my '91 running again after a total rebuild. Unfortunately my valves, or at least a couple of them, are making some noise. It isn't super terrible, but louder than I think I should get for these hydraulic lifters. Now, the lifters are all new, so maybe they are just still getting sorted, but I've run it at 2-3k rpm for a while (20 mins over a few sessions?) and driven it around a couple miles, and it hasn't stopped... any thoughts?

 

It also misfires a bit, but presumably that is unrelated. Thanks for any advice. After doing the whole rebuild, it'd be nice if it ran really well.

[Precise1]

Did you soak the lifters for a day or two before install?? I seem to remember someone talking about that...

 

B

[Kingman]

I believe you're supposed to soak the lifters in oil for a few days with a ZDDP additive...

 

MY1PATH has a lot of information regarding the lifters and such, maybe he'll chime in.

[sewebster]

Hmm. Didn't do that. Didn't see anything about that anywhere. I guess the question is, "now what"? The right side is easy to get to, but the driver's side... can you even remove the valve cover without taking off the intake plenum? But possibly if the only thing is I didn't soak them then it could get better. But I almost think it's getting worse... hard to tell without having run it for very long. I'd just like to avoid a problem if possible. I don't want to have to replace the valves again. It's got new valves, lifters, rockers and rocker shafts...

 

I am using RP Break in oil, which supposedly has lots of ZDDP

Edited October 18, 2010 by sewebster

[Kingman]

Oops.

 

Basically the lifters are dry as of now, there might be oil around them but not thoroughly in them. If it were me I'd take the plenum off and pull the lifters, and soak them in oil for a few days then put them back in and see what happens.

[sewebster]

Oops.

 

Basically the lifters are dry as of now, there might be oil around them but not thoroughly in them. If it were me I'd take the plenum off and pull the lifters, and soak them in oil for a few days then put them back in and see what happens.

 

Hmm. But isn't oil basically pumped into them whenever the engine is running? I guess if there is air inside then it might not be able to get out under the oil pressure. I guess I have to drain some coolant to take the plenum off... anyone know how much?

[CrazyLarry]

I have not rebuilt a vg30 yet,

But i know with a SBC you soak them and pump them by hand using a push tube until no bubbles come out.

vg30 not having push tube not sure if you can hand pump them.

[MY1PATH]

Ok, so new lifers;

1 did you keep the upright at all times? The come with a small amount of oil in them but they can bleed out.

2 Did you use a high quality assembly lube? without it, the first few engine revoulutions (the initial chatter) will score the inside of the lifter becase there is nothing to absorb the shock so it goes to the inside of the lifter.

3 ZDDP!!! and this should be in red letters at the top of of your build list. the first start with new lifters must use High quality zddp oil (like royal purple or brad penn racing) and a High ZDDP (like schneider Formula 2) break in additive. The insides of lifters move just like pistons but they don't have rings to seal them so its about precision fit and proper procedures to ensure they don't score and leak during their first use. They need to have as much wear porotection (ZDDP) as possible so they polish eachother instead of the opposite.

 

4 run in procedure.

Oil psi is 7-10 at idle, this will not protect any new components nor will it keep new unpolished lifters full of oil.

 

break in properly to prevent pre-mature wear;

1 start engine and raise RPM to 2000 if there is a prolbem stop engine fix it and start again DO NOT LET ENGINE IDLE untill 20min RUN IN is complete

2 RUN 2000 rpm for 5 min

3 run 3000 rpm for 10 min

4 fluctuate 2000~3000 for 5 min

5 lifters are now run in let engine Idle and turn it off.

 

at this point I reccomend changing your oil. I also recomend you have zddp in your oil @ all times because it protects the lifters. Most oils nolonger contain this substance.

Don't rev above 4000rpm for the first 250 miles

the link below is for cams but there are lots of pictures to help you visualize the process.

http://npora.ipbhost...showtopic=15422

[sewebster]

1. I kept the lifters upright from the time I received them, but they were shipped randomly in a box. They were just in cardboard. They are sealed power brand.

2. I used decent assembly lube, but I don't think any got inside the lifter, just the outside.

3. I used RP Break in oil, which apparently has high zddp.

 

I did not idle the engine on initial start up or until after it had run for at least 20 mins. I installed a real oil pressure gauge and it was always nice and high for the initial stage, like over 50 psi. I didn't follow your break in procedure exactly down to the minute, but something fairly similar.

 

So I need to figure out if I should:

a) assume it is the lifters and try to "break them in again" or just wait a bit to see what happens

assume it is the lifters and pull them out to soak them

c) try to figure out if it is some other problem

 

I need to decide if I want to drive about 200 miles this weekend with the truck or not pretty soon. Hmm.

[MY1PATH]

It can and will drive, it just may be noisy. The damage to the lifters is already done you can try to quiet them but their life has already been shortened.

I think they most likely bled out during shipping. Filling/soaking is also done when engine is running so removing themto do so will not help. In your shoes I would drive it as is and save up for new lifters. Did you check your rockers? if the pad on either end is worn beyond limits the lifter will never get tall enough to stop the chatter.

Cam lube is not needed inside the lifter just the sides, top and bottom.

When I got my lifters they were shipped the same way. I oppened each one and put severlal drops in each one when I was modifying them. the video for opening(modifying not necessary for your engine) and filling them is here.

 

you can also put them in a pan with oil and depress the pluger several times with a blunt opject. (like a handle of a screw driver) you want them to be firm not spongy when installed.

Edited October 18, 2010 by MY1PATH

[sewebster]

New rockers... I guess my concern at this point is damaging the valves, since I just replaced them and I don't want to pull the heads again (or re-do the valves again... $$$). They should really just ship the lifters sealed in oil somehow (in a sealed plastic bag etc.).

 

Do you think this is the most likely problem then? I guess so. Not sure what else would cause valve noise...

[sewebster]

So are you suggesting that the lifters could have seized, and the reason for the noise is that they aren't getting long enough?

[MY1PATH]

So are you suggesting that the lifters could have seized, and the reason for the noise is that they aren't getting long enough?

 

 

Not seized, a lifters usually chatter for 2 reasons

1 exessive play from rockers or other components being too worn

2 lifter not holding enough oil preasure and collapsing

 

If a lifter internals are scored from lack of oil during break in 2 would be the case.

If a lifter taps for a few seconds on startup but gets quiet before the engine gets warm 2 would be the case

If there is constant chatter that goes away or gets quieter with RMP (not drowned out but gone) 2 Is likely the case

If chatter continues thru RPM 1 is likely the case

 

You can also take your vavle cover off and see if there is any play in the rockers.

 

Lastly, you should know, no valve damage will occur from a bad lifter unless the outside of it is physically seized in the lifter galley and that is nearly impossible considering you just did a rebuild with new lifters. Thats the nice thing about hydraulic lifters

[sewebster]

Found the problem... some of the new lifters seized occasionally in the guide, as they were manufactured too large in diameter. Now my cams are destroyed. Best rebuild ever. Hurray for Sealed Power. Maybe they'll send me new cams. Ha.

[MY1PATH]

wow! Good thing I use the word "nearly" when I said "nearly impossible", do you remember them fitting tight in the lifter galley when you put them in? Mine kept falling out (normal) when I did mine so I had to wire them untill they were sitting in the heads.

I used Clevite Lifters and I think they were $120 +shipping from northern auto parts. They looked top shelf, no casting marks and even the non-contact surfaces were machined smooth. Looked allot better than the originals I pulled out.

PM 5523Pathfinder about some eurospec cams I think they are trying to clean them out for $50 or something cool like that. You'll get pretty much the same MPG but with a little more go when it comes to highway maneuvers.

 

So if Sealed Power hangs you out to dry hopefully you can be good to go for under $200 +break in oil.

Good Luck.

[sewebster]

Yeah, I'm just hoping there is no more damage when I pull it all apart. I think I may have heard some piston/valve contact at the end when the cam was worn down enough, but I'm not sure. I'll pull the heads tomorrow. But if I just need to replace a couple valves again that isn't such a big deal... we'll see.

 

In retrospect, some of the lifters did seem tighter than the old ones, but nothing too bad. And that kinda makes sense, since you might expect the old ones to be somewhat worn. Even now though the oversize lifter I examined actually slides ok by hand in the guide... but it is 1 thou above the upper diameter limit (the range is only 0.6278"-0.6282", so 0.6292 is huge). I'll have to see if I need new lifter guides now. Those could be harder to track down.

[krmiller07]

I am interested in these "Euro-spec" cams. Can anyone tell me where, or who I can contact? $50.00 seems pretty reasonable if there new cams. Or are these ground for the 300 ZX Normally aspirated?

Thanks,

 

krmiller07

[MY1PATH]

Yeah, I'm just hoping there is no more damage when I pull it all apart. I think I may have heard some piston/valve contact at the end when the cam was worn down enough, but I'm not sure.

Valves Move Less when a cam wears down. But if a lifter was stuck and the valve couldn't close than maybe. You do realize each valve has over 50lbs of force trying to pull it shut at all times.

 

I am interested in these "Euro-spec" cams. Can anyone tell me where, or who I can contact? $50.00 seems pretty reasonable if there new cams. Or are these ground for the 300 ZX Normally aspirated?

Yea, see quote below or read posting above.

PM 5523Pathfinder about some eurospec cams I think they are trying to clean them out for $50 or something cool like that. You'll get pretty much the same MPG but with a little more go when it comes to highway maneuvers.

[sewebster]

Anyone ever pulled the cams without pulling the heads? Looks like they will thread out the front if I remove the grille (took the rad out already)... but I'm not sure if I'll be able to get a ratchet on the rear bolt. Hmm. One way to find out I guess.

 

Do people usually replace those gaskets on the rear head covers? I used some that came in my full gasket kit, but don't see them available separately. Could try the dealer next.

[MY1PATH]

Anyone ever pulled the cams without pulling the heads? Looks like they will thread out the front if I remove the grille (took the rad out already)... but I'm not sure if I'll be able to get a ratchet on the rear bolt. Hmm. One way to find out I guess.

 

Do people usually replace those gaskets on the rear head covers? I used some that came in my full gasket kit, but don't see them available separately. Could try the dealer next.

 

 

Somones gonna pick on you for not searching, Its in the how to section so you don't even need a keyboard.

http://www.nissanpathfinders.net/forum/index.php?showtopic=15422

 

those covers on the back will make you think you have a bad RMS if they leak. I just sraped the gaskets and used a bead of rtv.

Swivel head rachet is very handy for the rear bolt but here's another secret;

unbolt the trany pad from the cossmember and put a jack under the tranny(NOT the T-case, you could cause a leak) Jack up the tranny till it barely touches the tranny (tunnel 1-2" if you have a BL) this tips the engine foward and gives you more room to reach that bolt.

[sewebster]

Cool, thanks. Pulled the cams today.

[sewebster]

ARGH! Just got a set of 12 Beck/Arnley lifters. 10 out of the 12 of them are oversized (8 or 9 10ths of a thou over, which is almost as bad as the previous ones that seized). This seems insane. I'd doubt my micrometer, but the zero is good, and it seems all the lifters I've measured (either brand) are either spot on, or almost 1 thou over. Nothing in between or whatever. The guy at rock auto said they don't get many returns, but I can't see how since the other oversized ones caused instant destruction for me.

 

Maybe I should try harder to get the Clevite brand.

Edited October 29, 2010 by sewebster

[MY1PATH]

ARGH! Just got a set of 12 Beck/Arnley lifters. 10 out of the 12 of them are oversized (8 or 9 10ths of a thou over, which is almost as bad as the previous ones that seized). This seems insane. I'd doubt my micrometer, but the zero is good, and it seems all the lifters I've measured (either brand) are either spot on, or almost 1 thou over. Nothing in between or whatever. The guy at rock auto said they don't get many returns, but I can't see how since the other oversized ones caused instant destruction for me.

 

Maybe I should try harder to get the Clevite brand.

 

maybe you could give your lifter galleys a wet hone with 400 grit. also keep in mind aluminum expands more and at lower temps than iorn . you lifter galleys are aluminum.

[sewebster]

I picked up some "new to me" used galleys from an engine rebuilder place for $10 each... because mine were slightly out of spec (too large of course). But maybe I need to use my old ones and try to enlarge the holes even more! But there's basically no way I'm going to try this and risk destroying my new cams etc. again... Ideally everything would be in spec and just work.

 

Unfortunately one of the "good lifters" I just got was "soft" too, totally squishy so I guess the oil leaked out.

[sewebster]

Clevite lifters are coming... I really hope they are good this time!

 

The new cams I got (Beck/Arnley) seem to be slightly too short (can't rotate when you tighten the rear bolt). The dealer can't get the locate plates anymore, but that wouldn't have helped anyway, as the max adjust in the negative direction those go is about 1 thou. Mine needs 5 thou shimming to get within spec! I guess it is easier when it is off in this direction because you can just add a shim washer. If it's the other direction you'd have to get your washer/plate ground down in the center.