maz87t2

iTrader: (6)

Ok lets start off with the mods. 88 se with T2 swap, to4b turbo, front mount, rtek 1.7
s-afc, 1200cc secondaries 720 primaries, areomotive sp? regulator, walbro 255 pump, tuned for 11.5afr at 10 psi. 3 inch all the way back to cork sport muffler 50mm wastegate

Ok here's what happened. the other day i went to Wal Mart and on the way home i opened it up in second and third. i shift at 7800 rpm give or take. was running perfect didn't miss a beat. then i was driving normal shifting at 3 and 4000 rpms for a couple miles then all the sudden feels like a major miss. sounds like a stupid v6 with a fart can. so i bought new plugs. still the same. changed out trailing coil since i had one laying around no help there. it idles perfect and makes some power. my turbo will go to 10 psi but the engine sounds like crap. it pulls -20 vacumm on the down rev. it smokes a little bit. not to bad.its always smoked Doesn't over heat. i did a compression test tonight but i didn't do it right. i looked it up after i took the tester back. I'm gonna get it again tomorrow and try it again. what are some other things it could be? i guess if the engine is blown its either gonna sit for a very long time or its gonna be parted out. I'm laid off at the moment and have no money to throw at this thing. let me know what you guys think. thanks Ryan and i'm not a newbie. i know how to do everything to this car besides rebuild the engine. i guess it might be time to learn huh lol

vato2000taco

iTrader: (1)

boost leak will cause shuddering at high rpms under boost but rpm range varies on how bad the leak is mine studdered around 6g and i had a vac leav at stock bov hole that was blocked off. look for vac leak after the [afm ]air flow meter

SoloII///M

iTrader: (13)

Throw a timing light on each plug wire while the car is idling and check for a fire. If everything checks out re-do the compression test, holding in the release valve pin while someone cranks the motor. It sounds like you dropped a seal.

maz87t2

iTrader: (6)

yea we re-did the compression test and the front rotor does 3 60psi bumps and the back does one 30 and two 0psi bumps. so its junk. i pulled the turbo manifold off and felt all 6 seals and they felt fine. u could push them in and they would come right back out. so i guess its broken closer to the side.

maz87t2

iTrader: (6)

oh yea i forgot to mention it has 3mm seals fd corner springs and all the goodies in it. im trying to figure out what would make this engine pop. its as built as u can get. anyone know of a cheap but really good rebuilder?

vato2000taco

iTrader: (1)

i got a buddy that builds engines in fla got his numberif u want it he's puertorican if u know what i mean . they are the best rotory mechanics imo lol

FC3Sdrift

iTrader: (5)

maybe the 7800rpm's with the 3mm seals?

R.O.D

iTrader: (3)

^really?? never heard of that being a problem...
3mm's doesn't make it a diesel engine

possibly a lean out.
mine is doing almost the exact same thing.
but my comp test showed ok.
as i was reading down the thread i was hoping to see a slolution
sorry to hear the motor popped

maz87t2

iTrader: (6)

11.5 afr lean? hmm. i pulled the turbo manifold off and felt all three seals on the back rotor. all three are still intact and springs still work perfect. there were no cracks or anything. do these things all the sudden just wear out? and i never knew u couldnt rev a 3mm engine that high. i would like to know how high u can rev a engine with 3mm seals. i never had a problem for 2 years going that high. i have a fuel cut defenser in my chipped ecu so it wouldnt cut fuel. the housing feels fine as far as i can get my finger. idk i guess we are gonna tear it down.

R.O.D

iTrader: (3)

sorry i didnt see that part, shouldve been fine.

no i've never heard of a problem reving 7k with 3mm's

could be something dumb

tps or afm happen often enough that it may be one or both of those

did u happen to notice engine temp, maybe it got too hot, and warped something.
im just shooting in the dark, throwing out ideas, sorry

SoloII///M

iTrader: (13)

The 3mm seals don't give you any more threshold against detonation so it's likely the fueling had an "event" and you got a ping. probably when you did a high boost run and it took a little bit for the seal to completely crack and exit the motor.

Bummer.

maz87t2

iTrader: (6)

it must be the very edge of the seal they feel fine just alittle wore out. i felt no cracks or anything. i guess ill find out in the next few days what happened to it when i tear it apart.

SoloII///M

iTrader: (13)

If you have zero psi bumps, they're broken. Or you threw a spring. "Worn out" won't do it.

maz87t2

iTrader: (6)

i know that. but u can run ur finger across them and they feel perfect. no pieces missing. so idk. i guess we will see. im gonna yank it tomorrow. and start taring it apart.

R.O.D

iTrader: (3)

i think solo may be misreading
u DO have compression correct?
and the apex seals feel good correct?

i dont think theres a reason to tear it down yet, theres so many little things it could be

can u check the front rotors seals?

EDIT: ok i reread, the side seals may have gone out. sorry, i forgot u said u did do a comp. test, but all six apex seals feel ok.

SoloII///M

iTrader: (13)

Seems pretty cut and dry to me.

FC3Sdrift

iTrader: (5)

i never said that was the cause, i was just guessing hence the question mark and the head scratchin, I've read on here people having problems with the 3mm seals. something to do with the tips of the seals rolling back. there was another forum member with a thread with a similar problem, search around and you can probably dig up more info on it


i have no experience with 3mm seals just my 2 cents
do you have to get the engine assembly rebalanced after you put the 3mm seals in? 7800 is spinning pretty fast

Jimmy2222

iTrader: (3)

Two 0 psi faces = no apex seal(age)

maz87t2

iTrader: (6)

pulled the engine apart apex seals look great. on the back rotor i had one broken side seal and the other one was stuck all the way in. what would make the side seal stick? lack of oil? like i said all the apex seals look fine. i have a question about the rear housing. where the spark plug holes are it looks like its cracking to the sides of the housing on both holes. what would cause this? here are the pics. how can you look at the housings and tell if they are good or bad?

RTRx7

iTrader: (2)

Those housings look terrible to me. Everyone has different opinions on that so the best way to find out is to check the fsm specs. Some say that if any of the second layer of metal is showing, the housings are trash. Yours show that much wear but just check with the fsm and see. If there is cracking *I can't tell* then get some new ones. This would be a great opportunity for a port if you like.

maz87t2

iTrader: (6)

thats just the back housing. the front one doesnt look near as bad. here are pics of the front. they already have a large street port. im thinking if i get new housings im gonna get a bridge port.

SoloII///M

iTrader: (13)

Junk pile for those.

turboIIrotary

iTrader: (9)

your side seal wasn't clearenced correctly i had a turbo2 with 3 mm seals and it did the same exact thing as yours.

maz87t2

iTrader: (6)

that sucks. what would make it all the sudden stick?

SoloII///M

iTrader: (13)

Side seal not clearanced properly is one possibility. Side seals have to be clearanced with all of them installed on one face, and the corner seals need to be installed as well (obviously).

Did you measure the side seal side to rotor clearance? Most people do not and it is critical.

Could have been carbon left in the side seal grooves as well.