Rocker Damage

[rossman]

I have a bad feeling a complete engine tear down is going to be required....  This is not simple wear. This is hardened metal chips flowing through the whole lubrication system. Sorry man. That sucks big time.

 

You " may " have gotten lucky, especially if you have a Magnetic drain pan. But only sure way is a thorough inspection of complete engine. If you do start finding metal chips in oil filter pleats, embedded in Rod and Main bearing material etc, there are certain additional steps that should always be done with this type of failure.

 

1: If you are running an Oil cooler. Throw it out. Metal chips will get stuck in turbulators of engine oil tubes and in corners. Even Ultra Sonic cleaning will not get them out.

 

2: Oil cooler hoes. Toss them out if they are AN with liners. The chips get embedded in the hose lining and can not be properly cleaned out. Some will remain, and eventually work their way loose and go thru the bearings. Hard lines ( Metal Tubes ) can generally be flushed out safely.

 

3: All oil passages in engine block and cylinder head should be cleaned with Rifle brushing ora a similar method. That means removing all oil passage plugs. High pressure solvent blasting after cleaning with the Rifle brushes. Head can be Ultrasonically cleaned. So can block if you can find a Tank large enough. 

 

4: Turbocharged?  If using AN hose for lubrication and drain, throw out the hoses. Chips can embed them selves in that hose liner as well. Check the CHRA and blast clean with lots of solvent and air. Clean any restrictions thoroughly. Ball Bearing CHRA's may need to be pulled apart and checked for debris in bearings. Journal bearing are generally a bit more robust.

 

5: Oil pump will of course have to be pulled apart and checked. Don't forget to thoroughly clean all oil  passages in Timing cover

 

Please feel free to Chime in if I've missed anything... GL.

Thanks for the advise Chickenman.

 

1) Nope, never installed it still sitting on the shelf

2) None, see above

3) Check

4) Check

5) Check

 

I'll be calling Rebello today to discuss.

[NewZed]

It's just a few flakes.  They might not even have left the top of the cylinder head.

[rossman]

Talked to Dave. He has seen this before.  The good news is that they block off the bypass valve on all their engines so that all the oil gets filtered.  He doesn't know what causes the spalling.  It just happens sometimes.  He said that the zinc additive in the oil I'm using isn't working.  The surfaces are too shiny, should be more grey.  They use a blend of Motorcraft, Pennzoil and Lucas break-in additive. Replace the rockers with good used original Nissan rockers, use the recommended oil blend and I should be good to go.  This is what he has done for his racing engines and it works.  

[Leon]

I had a similar failure on reground rockers, also on the trailing side of the pad. I think the trailing side sees more wear because as the cam lobe sweeps across the rocker pad, the lever ratio over the valve spring is increased. This puts more stress on the lobe/rocker interface the closer the lobe gets to the rocker pivot.

 

Mine failed using a "good" oil, Brad Penn. Once I replaced the REGROUND rockers with new (combo of aftermarket and Nissan) they've been wearing in really nicely. Only have about 500 miles on them though...

 

I didn't do an engine teardown, just changed the oil.

[Chickenman]

Yeah.. Royal Purple doesn't have a good reputation. Oils that do have a very good Track record are  Amsoil 10w-40 AMO, any of the Amsoil Severe duty grades, Motul Synthetics, Redline  and Joe Gibbs Hot Rod Synthetic ( High Zinc ).

 

My engine was new from the ground up in 2014. Engine builder recommended Delo 400 30wt for break-in ( Pennzoil 20w-50 is also good... lots of ZDDP ) . Changed oil and filter at 100 miles. Fresh Delo 30wt. Broke in further to 1,000 miles. Switched to Joe Gibbs Hot Rod Synthetic 10w-40. 4,000 miles on motor now and I have not had to add a drop of oil. Camshaft and rockers ( factory Nissan... good used ) look brand new.

 

I've used Amsoil products for several decades and I swear by there products. That being said, they are expensive. I my Turbo Audi I use Shell T6 Synthetic 5w-40. It's a Hi Zinc HDEO ( Heavy Duty Engine Oil ) that works very well in flat tappet engines. And you can't beat the price point. Turbo guys and air cooled bike guys like it a lot. Both types of vehicles are really tough on oils. 5w-40 might be a bit too thin for the larger clearances that the L-Series were designed for.

 

We had an excellent Tech article at VW Vortex on oils for Big Turbo cars. It's a sticky in the FAQ. Has lists of Zinc and Phosphate levels of popular oils.

 

http://forums.vwvortex.com/showthread.php?5867396-Built-Engine-Big-Turbo-Heavily-Modified-engines(aftermarket-cams)-what-Engine-Oil&highlight=Big+Turbo+oil

 

True Ester Synthetics such as Amsoil, Redline, Motul and Joe Gibbs/Driven ( Joe Gibbs/Driven Oil is actually a new formulation , supposedly superior to Esters ) are THE best Synthetic oils you can buy. But they are expensive. Other cheaper brands are less expensive, but are made from Hydro-cracked  Group 3 base stock which is not a true Synthetic like Esters and PAO. In Europe and Japan, you can not legally sell Hydrocracke base stock oils  as Synthetics.  You can thank the US Congress  and some of the big USA Oil companies that got the Feds to relax the USA standards for Synthetic oils back in the late 1990's.

 

Joe Gibbs ( Or Driven Oils as they are now known ) have excellent Technical articles on the different requirements of Race engines, Hot Rod motors and Vintage engines.

 

http://www.superchevy.com/how-to/additional-tech/1312-driven-racing-oil/

Edited July 5, 2016 by Chickenman

[rossman]

Thanks guys.  I'm going to go with what Rebello recommended, oil and rockers.  

[Tony D]

Leon covered exactly what I would have said regarding the 'trailing'--- the rocker ratio on an L-Series is variable. Where it contacts the pad is in the 1:4's, and it increases as if gets closer to the pivot ultimately in the 1.5+ range closest to the pivot. This is different than say a roller rocker which FIXES the point of contact of the cam to one point of pivot and the ratio is purely a function then of pivot to contact point to total length. Slider pads have a variable contact point with more pressure exerted as the pad wipes off the end closest to the pivot.

 

This could be a cam grind issue as well. If not properly profiled the loads will increase quite quickly. But that would be exhibited early in development. I don't think the case is applicable here. 

 

A reground rocker simply has thinner hardened metal, if you want to use an analogy think of a thin metal plate over soft sand... If you were to step onto a hard plate you may make is spring a bit into the softer sand underneath but it will spring back. Inadequate thickness of the hardening can led to the metals fatiguing and flaking out from a similar action. Once the softer metal underneath is exposed, then it really starts machining away in earnest!

 

I've not seen spalling like that on new OEM parts. I have seen rockers cut into cams..and occasionally cam faces spall. Cams aren't always flame hardened like most Nissan Grinders do (or nitride, carburize, etc...) Usually the rockers kill everything else.

[rossman]

I ended up purchasing a set of new OEM rockers from Courtesy Nissan.  They are listed as 1984 Maxima rockers but should be the same.  The guy from Datsun Parts had a set listed on Ebay but I didn't trust that they were really Nissan since the ad didn't actually say Nissan.  That and his smart ass response when I asked the question.  

 

Thanks to Chickenman for providing the link:  http://www.courtesyparts.com/nissan/maxima/13257w0300/1984-year/gl-trim/2-4l-l6-gas-engine/engine-cat/engine-scat/?part_name=rocker-arms

 

I think I'm going to have the cam inspected and micopolished if necessary by Isky for the extra insurance.  

Edited July 12, 2016 by rossman

[Chickenman]

Yes, the Maxima rocker arms are exactly the same part as any other L-Series motor.  4 or 6 cylinder. GL. Keep us posted.

 

Edit: Regarding camshaft  breakin. With new rockers follow the same procedures as breaking in a brand new cam and new rockers.

 

1: Get Isky to supply some of their breakin lube when they send the cam back. Coat the Cam  and rockers liberally with the break-in lube.

 

2: Use a dedicated Break-In oil by Comp Cams, Joe Gibbs/driven , Edlbrock or what ever Isky recommends. Or use Delo 400 30 wt or Pennzoil 20/50wt Dino Oil . Do not switch to Synthetic oil for about 100 miles.

 

3: If possible, Prime the oil system before cranking. Take a old distributor drive shaft and machine the gear off it. Remove Dizzy and support collar. Chuck a 1/2" drill onto the priming shaft and run drill until you have oils coming out of the cam and or oil spary bar holes.

 

4: When starting engine, make sure it is ready to go at first touch of the key and make sure that it can keep running for at least 20 minutes. Have all your fluids topped up and Timing set properly ahead of time.

 

5: As soon as engine starts, raise rpm to a minimum of 2,000 rpm. Do NOT let the car idle. You want lots of oil spraying on the rocker and cam lobes. Vary engine speed  between 2,000 and approx 3,000 RPM. You don't need to go any higher, but holding at a constant speed is not good.

 

6: Never EVER use an Energy Star motor oil on these engines. Particularly with higher pressure valves springs. Energy Star oils are usually thinner weights such 0w-xx, 5W-xx, 10w-30. Energy Star oils all have reduced amounts of ZDDP which is essentail for the longevity of high performance camshafts with higher lifts and higher valve spring pressures.

 

I've given my recommendations on oil. I prefer an Ester based Synthetic ( once Camshaft, Rockers and rings are broken in ) such as Amsoil 10w-40, Joe Gibbs 10w-40, Redline or Motul. Dino oils such as Pennzoil 20w-50 are OK if you prefer Dino oils. ... the heavier weights  are the ones to get as they are not Energy Star rated. The ES oils have reduced ZDDP too meet EPA standards.

 

An interesting tidbit from my engine builder on Dino oils.... and I've heard this before on oil forums such as Bob Is The Oil Guy. And BITOG has engineers confirming this.  Pennsylvania  crude oils ( Pennzoil, Brad Penn etc ) are apparently a better crude oil than Western brands ( Quaker State, Havoline etc). Has to do with geological formations and  the aging of the Dinosaur oil deposits. Oil deposits are apparently like fine Wines. The longer they age, the better they become. Since the oil deposits back East are Millions of years older than Western deposits, the better the base stocks become. I'd take this with a grain of salt... but it's an interesting observation.

Edited July 12, 2016 by Chickenman

[rossman]

Thank you Chickenman.  I will prime the engine but instead of messing with the pump I'm going to pre-prime the cam by pumping oil thru the oil pressure sensor port until oil comes out the cam and spray bar then crank the engine *without the rockers* until there is good oil flow out the cam and spray bar.  I'll have everything set up, install the rockers, set the valve lash then start it.

[rossman]

So I received new rockers from Courtesy Nissan.  It's interesting to see the difference between these and the ones that came with my engine.  The shiny ones are re-grinds that came with the engine.  I'm not sure if they are the originals that came with the head but I suspect so.  

 

The new rockers are shaped slightly different.  The top and bottom flanges of the I section are more rectangular and don't have the same definite top ridge as the re-grinds do.    

 

 

 

 

[Chickenman]

Lat picture really shows off the casting flaws in the old rockers. Look at the bad casting lines near the rocker pivot and the casting void shown at 1:00 by the pivot. Machining marks around mouse-trap spring groove and pivot ball oiling hole are also very irregular compared to new rockers

 

Not up to normal Nissan quality, and I suspect those may have been reground aftermarket rockers??? IDK... Or maybe the new Genuine Nissan  rockers ( 13257-W0300 ) were just made from a newer forging die?

 

Abnormal tip wear on old rockers in Photo #2 as well. I think you dodged a bullet by catching this when you did.

[NewZed]

Looks like the Paraut symbol.  I just picked this image off the interweb.  Paraut was/is, apparently, an indirect OEM for Nissan.  Paraut/Atsugi/Nissan, something like that.

 

http://www.elautoparts.com/item.wws?sku=A4040-51981&itempk=86615&mfr=Paraut&weight=0.20

 

The wear on the other end of the arm is interesting.  Isn't the tip supposed to fit inside the lash pad?  Shouldn't it be worn across the full face?  Looks like it's sitting on top of something else and it's worn a groove.

[Chickenman]

^ Yeah... I was wondering about that tip wear too.

[NewZed]

I found some images of Nissan versus aftermarket lash pads and see that Nissan cut grooves inside the seat area for the tip.  Aftermarket is flat.  So the groove is just "normal" wear.

 

Still kind of wondering how the rockers got on the engine.  Is it a Rebello engine?  He recommended used Nissan but went with reground used Nissan.  Just seems inconsistent.  Didn't offer to repair their error either.  He's seen it before so knows about it.  Seems like they should have owned it.

 

Anyway, good luck with it.

[rossman]

The wear on the other end of the arm is interesting.  Isn't the tip supposed to fit inside the lash pad?  Shouldn't it be worn across the full face?  Looks like it's sitting on top of something else and it's worn a groove.

 

I believe it's normal due to the channels machined on the sides of the lash pad slot.

 

Edited July 15, 2016 by rossman

[Chickenman]

That would do it.

 

Still the tip wear is excessive for such low miles on your engine. I think the Royal Purple may have been responsible for that, Unless the Rockers tips were reground as well and went through the surface hardening too. Either way it adds to tales of woe that seem to go with Royal Purple....

[Tony D]

it almost looks to me like the new rockers are cast, whereas the old rockers are forged. I can't see them revising dies to make the parting line nonexistent.

It's almost worth putting one in the 6" Vice and whacking it with a big hammer to see how it bends or breaks. The break will tell the tale of forged vs cast. New one looks like an investment casting vs the old one with the traditional forging line.

[rossman]

I believe the new rockers are forged too.  It's just hard to see the parting lines since they are ground almost flat and the part is so dull it's hard to see fine details on it...and my crappy cell phone pics.  These might help.

 

[Chickenman]

I can see the parting lines fine. And they are wide like most forgings are.

 

Those are OEM Nissan rockers and I highly, highly doubt that Nissan would be using cast parts. Or allow any of their manufacturing partners to deviate from factory specs.  Forging dies and moulds do wear out over time. It's certainly no big deal for a manufacturer to have new ones made. It's done all the time. 

 

And as mentioned the 13257-W0300 is the superceded number for all L-Series rockers.