SexOnWax

I was having issues with the motor struggling to stay running at idle. Once I put the vehicle in gear, the car would die and would not start again until the motor was completely cool. The last time it ran, I did notice white smoke pouring from the exhaust. Immediately I thought blown head gasket. A compression test was performed to verify this. At only 6,000 miles on what I was told was a fresh rebuilt S14 SR Zenki motor, this was the first time I opened the valve cover plate to get to the spark plugs. Notice what's written on the first ignition coil? Not a good sign.



The test revealed cylinders 3 and 4 both read at 138psi while 1 and 2 showed 125 and a whopping 35psi respectively. Argh. We then pulled the valve cover and saw the condition of the cams. Cylinder 1's cam lobe on both intake and exhaust sides were perfectly fine. The other three were grimey and if you notice on the first picture of the lobe up close, the middle section was grounded down and there are two little edges that show this. So cylinder 1 cam lobe edge looked like _____ but the other three are |_____|.

The motor only has just over 6,000 miles on what I was told was a rebuilt motor using new stock components with the exception of an Apex metal head gasket, ARP headstuds, and rocker arm stoppers internally while running a Tomei Arms M7960 turbo on a Power FC D-Jetro. I fear that my problem is much much worse than just a blown head gasket and cams. Can anyone please help shed some light on this?

Oh, and to the shop that installed this motor, you know who you are. I am withholding any negative comments about you until I can pinpoint the exact problem. Rest assured, justice will be served if it was complete negligence on your part.

OrangeVirus1

They just look oil starved. is the oil pump working?
It looks like possibly one of those Shit engines you get from japan that Never had it's oil changed For over 50k miles

I'd say tear the engine apart ( you got to, to change the head gasket ) and inspect for more problems. Hopefully your cylinder walls are still looking fresh.
take off the oil pan too.

After verifying everything, replace the cams and rockers, while doing a thorough cleaning of the head and oil galleys.

it looks salvageable.

R_34

Looks like your cam oilers are clogged.

Motary

This can also happen if you put a washer between the lubrication tube and cam cap. It could also be that the rocker arm stoppers are stopping oil from getting through the cap to the oil tube, it's a banjo type of a passage, you should probably check that too

jr_ss

The RAS aren't blocking oil from dripping on to the lobes, just just looks like it was starved of oil.

I'd pull the oiler tubes and flush them over a strainer to see what comes out. Make sure they are extremely clean. As stated, replace cams and rockers as necessary and clean the head thoroughly.

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Kallixtos

Like Orange Virus said it might be one of those crap motors that never had its oil change. If the shop didn't do a good job cleaning the galleys there might have been some left over sludge that broke loose and plugged something up.

I've also seen valve stem seals cause grime like that in the valve cover. Either way you have to tear apart the head to inspect.

silnv

Definitely looks like clogged oilers. They are just tiny pin holes, doesn't take much. Especially if the oil is not changed on a regular basis.

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Johannes

No oil in the valvetrain could also be that the cam caps for #1 and #5 are switched around.
This happened to my friend's rebuilt SR20. He wasn't getting oil on every cam lobes.

Low compression could also mean that the valves aren't opening up all the way, but in this case, like everyone else is saying, it seems like it clogged up the oil passages/squirters/discharge system and ate through the cylinder liners&piston rings. It seems like it's time for a full rebuild!

cotbu

Those cams look absolutely normal, for a valve train that's been starved oil. There should have been a clackkity clackkity clack clack sound as well.
The gunk on the rocker arm looks like cam lube.

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GuardianLlama

crank your motor (don't start) with the valve cover off and check.

you should see oil.

SexOnWax

Got around to pulling the head off and this is what was inside cylinder no. 2. Note the really dark area along the middle of the cylinder wall:





Sooo... between this, chewed up cams, low compression, and a burnt ass spark plugs (all from the same cylinder), a new(er) motor is on its way.

I'm going to do the same setup internally with but new parts of course. Will I need to get it retuned once every thing is back in working order? My hope is that its just a matter of dropping in the new motor, bolt on all the same turbo bits and such from the old one, and off we go. By using the same S14 Zenki motor, metal head gasket, Power FC, etc., it should run like before, minus the oil starved cams. The nearest tuner is about a three hour drive and I'd be way too nervous to drive it out that far without any tuning.

Mikester

Is a newer motor cheaper than taking the time to do a fresh rebuild that you are 100% sure is good? Seems like a different motor opens up the possibility of new issues. Don't get me wrong, it's not a bad idea. Just wondering.

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S14DB

With the skirt wipe and the gunk in the head I would say this thing never had it's oil changed.

The lobes looked fine but the head had never been cleaned. The real killer is the wear on the bore. Need a new piston and hone. Hopefully not a bore.

S14 connections on the motor are the same. The harnesses are different. So a Kouki or Zenki motorset would work if you kept the Zenki engine harness and ecu(powerFC).
If everything else is the same you should be fine.

Damage was not from a tune.

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fliprayzin240sx

Considering the cam lobes over cylinder 1 are good, I'm gonna guess the damn oil drippers were clogged.

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Prok0

Yeah, make sure to clean your cam oiling rails very well (we would usually run parts wash through them and then poke at the oiling holes when any particulate gets clogged up in them until they flowed free, then clean the parts wash solution out and re-install). You can also drill out the oil galleys on the head and tap them, that way you can clean them out thoroughly and then install a plug when your done, as sometimes they will get clogged up as well. We used to do that on all the motors in our race program to ensure proper oil flow to the cams/lifters.

Also with the SR its essentially a flat tappet style motor and because of that there is a lot of friction on the cam lobe and rocker surface, in years past when there was a heavier zinc content in the oil you would not run into as much of an issue with wear on those components because the zinc helped keep everything lubricated. Now a days there are stricter regulations on oil contents and zinc has been reduced in many of the off the shelf oils, and thats part of the reason a lot of old flat tappet style motors are running into pre-mature wear issues in the head.

Its pretty well documented within the hot rod community, one solution is to run a zinc additive or an oil with higher content (usually not an off the shelf item)

The cylinder wall issue is another thing entirely though..

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S14DB

This is a oil change rate issue not a zddp issue with the cams. The amount of sludge in that head is appalling. Detergents had long burnt off.

Zinc would have helped with the cylinder wall and piston as it helps buffer the velocity changes. Constant rotation of a cam wouldn't benefit.

Couldn't see the other side of the cylinder but I would bet that wrist pin was binding causing skirt drag.

Rotella and other diesel oils have the zinc content that gas motor oils used to have before they were discovered to damage cats. They also have a higher detergent content.

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Def

ZDDP primarily helps high pressure sliding lubrication - which is exactly what a cam on a follower is. Not sure why you think it wouldn't help.


Although I agree the OP's wear is probably more due to lack of oil due to clogged sprayers than anything else.

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