White smoke after RB26 rebuild

[yamaha227]

Hoping someone can give me some advice on what maybe causing my GTR to blow smoke after a full rebuild. Its done about 300km's since rebuild, so i might be jumping to conclusions but it seems to be a fair bit.

Hear's what i had done, bore and hone to suit 20' over JE pistons, total seal ring set, forged Argo rods, new standard nissan crank and bearings throughout.

Head has been rebuilt with new valves Todda bronze valve guides and new seats cut. Also had my sump modified with a Trust sump extension kit and a N1 oil pump. had all this work done by a engine shop up here and put the rest of the gear back on myself.

Built the engine keeping in mind i wanted it to be able to make about 400kw at the wheels in the future. I have HKS 2530 turbo's on now with ces racing dump pipes and apexi exhaust, plus upgrade injectors, fuel pump and Apexi power fc, mines airflow meters and huge intercooler and a HKS remote oil filter/cooler kit to help keep things under control.

Bit of a run down on what ive done, hope this will help in sorting my problem out.

It seems to blow nice thick white smoke after it has been idling at the traffic lights when i take off and after i have been decelerating into corners and then accelarating out. but if i cruise at say 110 on the highway for a little while then change down and go round some tighter corners and accelerate and take it to 5000 with boost it doesnt blow any smoke at all.

The car was off the road for about 6 weeks with no battery sometimes, is there a chance the power fc needs retuning?

oil catch can doesnt seem to be getting any oil mist in it, i have the pvc valve blocked off and the line into the rear turbo intake boot is also blocked of, would this effect my crankcase venting at all, and having total seal rings would this add to the problem?

Before i had the engine rebuilt it was running fine, no smoke i had the HKS turbo's on it then to so it makes me think that i cant be the turbo's. or is there a chance that because they have been sitting for 6 weeks the seals me have dried up or something happened?

The engine was tuned with all the above mods down south in melb except for the pistons, rings and rods etc. i was hoping because i didnt change anything that would effect the mean effective pressure of the engine eg cams, boost level, CR etc that i would be fine with the existing tune on the power fc before my rebuild.

Im going to try and put as many k's on it over the next few days and load the thing up hills etc to see if it comes good, and will also keep an eye on oil consumption/oil level increse aswell. Have spent big bucks on this engine and hope the engine shop did the right job with bore and hone.

hopefuly somone has some good news for me on what to try, Thanks

[knore]

I dont know much about running in new engines and whats supposed to happen..

But im pretty sure its meant to produce some smoke

[whatsisname]

The symptoms sound like a piston failure! Oil is some how getting into the combustion camber. When you're at the lights with low cylinder pressure (idle) oil is making its way into the camber. This oil then gets burnt/blown out the exhaust as you take off. This is the exact same thing that was occurring when my #6 ringland let go!

Either that or the engine builder got it horribly wrong when he fitted your rings! Have you followed the correct run-in procedure? Surely glazed bores wouldn't be that bad?

Take heart in the fact that I'm no mechanic, so it may well be something simple that's easily rectified.

EDIT: I would've thought if it were a turbo seal then the smoke would get worse with boost. And the smoke would be constant. Yes?

[whatsisname]

I dont know much about running in new engines and whats supposed to happen..  

But im pretty sure its meant to produce some smoke

After my engine build (CP forgies and rings etc..) - ZERO smoke during run-in period.

[Cubes]

Valve stem seals damaged during install?!?!

In the engine manual it does state they are finiky.

[brettinoz]

Have you pulled your plugs??? Is any one of them oily or dirtier than the rest?-indicating an individual piston, ring or valve stem failure. Are three plugs dirty/oily??? Indicating one of the two turbos has failed??

[Sydneykid]

Hi yamaha227, what oil did you use to run the engine in on?

[gtrken]

Hi yamaha227, what oil did you use to run the engine in on?

You thinking maybe he used Full synthetic and things haven't bedded in yet?

The symptoms you describe are reminiscent of valve stem seals or turbo seal failure. Are you sure it's not blowing smoke at higher speed and you just can't see it. Have someone follow you and tell .

Cheers

Ken

[Merli]

You're using Mines AFMs with a PowerFC? Can I please ask what AFM setting you're using on the PFC as I'm about to put Mines AFMs on my RB26 as well

Cheers,

Andrew.

[hungry6]

I'm almost sure it valve stem seal, They have a tendency to buil up oil at idles and when u take of a white plumes of smoke is evident for a few seconds and disappear.

[yamaha227]

thanks for the replys, sydney kid... used valvoline sae 30 running in oil for the first 50k's until i heard it was not a good idea then changed to BP coarse 25w 60 mineral oil. what oil would you reccomend? have you had any experience with using total seal gapless rings and running in procedures?

[yamaha227]

Merli... will let you know tonight what the setting is on my power fc for mines A/F meters.

Gtr ken... my turbo's were running fine before the rebuild so was tending to think it may not be them... they were sitting around for about 4 weeks, not sure if this would cause any problems? thought if the turbo seals were gone it would blow smoke all the time, under decent boost and acceleration it only blows a tiny bit of black smoke, which it did before the rebuild, it is running a tad rich under decent boost and rpm im guessing to suppress detonation

[yamaha227]

I checked the plug in the forward cylinder this morning and it is showing signs of black soot building up around the circumfrence of the plug and the centre electrode is dark brown. using ngk BKR7E plugs.

Had new valve stem seals put in with the rebuild so maybe the engine shop may have got a couple wrong when putting them in... he is pretty switched on, but you never know?

will try to get a comp check and leak down check done soon but will try to put a few more k's on it first. engine is running strong and not missing or rattling, had crank, rods pistons and clutch all balanced, bit od a mystery??

[DCIEVE]

sounds like valve stem seal, have seen this happen on a freshly built motor recently

[Sydneykid]

thanks for the replys, sydney kid... used valvoline sae 30 running in oil for the first 50k's until i heard it was not a good idea then changed to BP coarse 25w 60 mineral oil. what oil would you reccomend? have you had any experience with using total seal gapless rings and running in procedures?

Ooooops wrong answer, rings will never run in properly with synthetic oil. Particularly gapless, are they top or second ring gapless?

We use basic Castrol GTX, 100% mineral oil, no friction modifiers. Gapless need 500K's to run in with mineral oil. We run 50K's then change the oil filter, just in case there was any left over crap in the engine build. Cheap insurance.

Who told you not to use the running in oil?

[yamaha227]

Merli... Power fc is set on, setting #4 80o rb 25 setting, hope this helps.

Was under the impression BP coarse 25w 60 is a mineral oil, which is why i put it in. peter at advan who did my sump for me said he wasnt keen on valvoline running in oils, so did the oil change to BP coarse. Got the total seal ring set so im guessing its all rings.

[Merli]

That's quite interesting, since the Mines AFMs are 70mm, not 80mm like the RB25 ones...

I think I'm going to have to do more research into this...

Thanks!

[yamaha227]

thats the setting it was on when i bought the car. it was tuned by ben at race pace in melb so im hoping its right.

Sydney kid, should be hitting the 500k mark tomorrow so will dump the oil and put some castrol GTX 2 in and see how it goes...

[yamaha227]

hit the 500 k mark last night, smoke seamed to be clearing up a bit so thought i was on the right track, so out with the old and in with some GTX 2 25w 50 and new filter. took it for a run round town, stopped at some traffic lights and nice white/grey smoke again on take off after idling for a while... got the shits and took it for a blast down the derrestricted highway for some high speed blasts... seems to be clearing up a bit again after another 100 k's. So is it oil pressure related, new oil combined with N1 high pressure oil pump? getting to much oil through to the bores? any ideas ?? seems to going really strong... will take it out for a couple of hours tomorrow on the highway and see if i have any success...

[Cubes]

Sounds more and more like valve stem seals to me.