Miata Turbo Forum - Boost cars, acquire cats.

Miata Turbo Forum - Boost cars, acquire cats. (https://www.miataturbo.net/)
-   General Miata Chat (https://www.miataturbo.net/general-miata-chat-9/)
-   -   Holy wtf mate, I need turbo help please. (https://www.miataturbo.net/general-miata-chat-9/holy-wtf-mate-i-need-turbo-help-please-28576/)

miatamania 11-25-2008 11:06 PM

Holy wtf mate, I need turbo help please.
 
Ok...so what the fuck. Greddy kit, SS oil line, 5/8" drain line, MS, stock injectors, etc.

Finally got the car to start, cold start still wont work. Idles ok, drives fine with the wastegate wired open, like a champ. Really rich if anything.

I decide to see what happens wastegate closed...go out, car gets very shitty all of a sudden, no throttle response...doesn't make boost, turn around, maybe a mile round trip....WTF?


I get the car back in the garage, pull the air filter off...turbo wont spin, its fucking locked the hell up.

I give it a second to cool, use a socket to twist...feels TIGHT, wont spin very well.
Cools a bit more, turbo spins perfect...like a damn ball bearing. So I check the oil feed, plenty of oil there and inside the top of the turbo. I start the car, it works...sitting still car idles better, runs, etc...give it some gas, and makes 4-5 lbs of boost just sitting there.


Turn it off, check, spins PERFECT...start car again, its locked up.


It is a BRAND new rebuilt turbo...I'm running mobile 1 synthetic. Timing should be good...

Think the bearings are fried...? It spun perfectly before I installed it...spun perfect when I let the car idle...FAST at idle too.


What the heck could have happened?



And...if I fux0red a bearing, I assume I can get a rebuild kit for it? *off to search*


Thanks guys.

Arkmage 11-25-2008 11:32 PM

pull your oil drain or feed line and verify that you are getting oil flow to the turbo. that doesn't sounds right at all....

TonyV 11-25-2008 11:53 PM

^^


Originally Posted by miatamania (Post 334444)
So I check the oil feed, plenty of oil there and inside the top of the turbo.

although i could see how its easily miss-able


just a thought but is the chra clocked properly?
(ie: feed @ approx 12o'clock, drain at approx 6o'clock)

that's only guess I have, or bad rebuild work?

curly 11-26-2008 12:39 AM

maybe try disconnecting your oil drain, plugging the engine port, hold it over a drain pan, and have someone idle the car for a second or two? it'll waste a little oil but it'll at least tell you it's getting oil. and it shouldn't be too high pressure either.

miatamania 11-26-2008 12:41 AM

I'll have to check that.

prolly best to pull the drain and make sure I'm getting flow THROUGH the turbo.

It seems pretty random, sometimes it'll spin ok, sometimes it wont spin at all...no inbetween.

patsmx5 11-26-2008 12:43 AM

+1 to unhooking the drain and making sure oil is coming out the bottom of the turbo. And make sure the drain is not restricted in any way. I think the "runs like shit" and "turbo don't spin" issues may be separate.

miatamania 11-26-2008 02:28 AM

You think the turbo not spinning wouldn't create some pretty nasty back pressure/blockage of the exhaust making for some nasty throttle response/stumbling?

zoom2zoom 11-26-2008 05:21 AM

if the shaft is loose enough, there is a chance it can spin fine at idle but lock up under load, not too hard to imagine. who rebuilt the turbo?

Arkmage 11-26-2008 08:20 AM

also, when it's cold try pushing/pulling the shaft in/out of the compressor inlet. It's possible that it is thrusting and one of the wheels is locking up on the housing.

Saml01 11-26-2008 09:31 AM

Have you tried giving it gas and watching if it spins?

My freshly rebuilt t25 didnt spin at idle either when I first started the car, then it did after like 50 miles of driving.

miatamania 11-26-2008 10:37 AM


Originally Posted by zoom2zoom (Post 334512)
if the shaft is loose enough, there is a chance it can spin fine at idle but lock up under load, not too hard to imagine. who rebuilt the turbo?

That is exactly what I was thinking

No idea who rebuilt it, I bought it from a guy who had it rebuilt and parted out.

miatamania 11-26-2008 10:42 AM


Originally Posted by Arkmage (Post 334530)
also, when it's cold try pushing/pulling the shaft in/out of the compressor inlet. It's possible that it is thrusting and one of the wheels is locking up on the housing.

I doesn't move in/out much at all...if anything, going side to side it feels like it might be catching on the side somewhere though :(


the compressor wheel feels fine. I wonder if its just catching on the turbine side?


Originally Posted by Saml01 (Post 334557)
Have you tried giving it gas and watching if it spins?

My freshly rebuilt t25 didnt spin at idle either when I first started the car, then it did after like 50 miles of driving.

It'll spin perfectly at idle sometimes, and then other times it will lock up, as in, you can rev/load the shit out of it and it wont move...then have to take a socket and try to move it to no avail.

brgracer 11-26-2008 10:49 AM

Turbo is going to need a rebuild, and I'd inspect the compressor/turbine blades as well to make sure they weren't damaged if they hit the housing walls. I can't think of any reason for a healthy turbo not to spin freely by hand.

Forgot to ask, did you clock the housing? I'd check the housing alignment as well, particularly the turbine side. A slightly cockneyed housing could cause a problems as well.

Toddcod 11-26-2008 11:34 AM


Originally Posted by brgracer (Post 334579)
Turbo is going to need a rebuild, and I'd inspect the compressor/turbine blades as well to make sure they weren't damaged if they hit the housing walls. I can't think of any reason for a healthy turbo not to spin freely by hand.

Forgot to ask, did you clock the housing? I'd check the housing alignment as well, particularly the turbine side. A slightly cockneyed housing could cause a problems as well.

I would check into that.

miatamania 11-26-2008 12:44 PM


Originally Posted by brgracer (Post 334579)
Turbo is going to need a rebuild, and I'd inspect the compressor/turbine blades as well to make sure they weren't damaged if they hit the housing walls. I can't think of any reason for a healthy turbo not to spin freely by hand.

Forgot to ask, did you clock the housing? I'd check the housing alignment as well, particularly the turbine side. A slightly cockneyed housing could cause a problems as well.


I didn't clock it yet. It looks like the factory position.

I'm just slightly confused as why it only spins some of the time. *sigh*

Now I'm debating rebuilding it myself, or sending it off...or sending it off and having it rebuilt, and machined for a larger compressor wheel, installed and rebalanced. *hmmm*

Braineack 11-26-2008 12:46 PM

if you hold the wheel, pushing firmly towards the edges at multiple angle, is there any place you can feel it make contact?

miatamania 11-29-2008 10:54 AM


Originally Posted by Braineack (Post 334631)
if you hold the wheel, pushing firmly towards the edges at multiple angle, is there any place you can feel it make contact?

Fuck. I do believe it does.

What could cause a damn failure like that in...say...20 minutes?


All times are GMT -4. The time now is 10:59 AM.


© 2024 MH Sub I, LLC dba Internet Brands