So I've been getting some overboost issues with my Blitz SBC and Saturday they caught up with me. The overboosting usually occures when I change gears to third at WOT. It jumps to 15 or even 19PSI and heavily detonates... I take my foot of the gas floor it again and the issues goes away.
Anyway, Saturday I had a track day. Single 8 lap race. When I finished the race I noticed my turbo was glowing red... weird never had seen it like that, but I had never ran 8 laps at 7-9PSI before either. So I dismissed it. I did see lots of white smoke, it was pitch dark and I was using a small flashlight to see so it could be some other color, but without smell.
I let it warm down. Shut it off and go see the rest of the event. When I started my drive home the car started acting strange, loss of power and when I started hearing a clanking noise I shut it off immediatly. I open the hood and the turbo was glowing red, and I was only doing like 60kmh on the freeway in fifth. Was towed home.
Yesterday I went and checked my engine. Here is what I found:1. No oil reaching the turbo, that would explain the turbo glowing red3. Missing almost all water in the rad2. When I was crancking the engine (no plugs) to check oil flow to the turbo I saw water come out of one of the exhaust mani gaskets which was blown.3. No water in oil it seems cause I even open up the valve cover and didn't see any.
So my conclusions are:1. Blown head gasket, water entering combustion chamber2. Faulty oil pump (?), hope this hasn't caused more severe damage to the engine.
Unfortunately I'm flat broke right now so I can't really take it to my mechanic. I'm gonna start checking stuff to see if there is something else wrong. Anything I should/can check in my own garage at my house?
Live and learn, I say. First thing I'm buying when I get off my back is an oil pressure sender to hook up to my SBC.
Just wanted to vent.
Overboost killed my engine
-
Structure240sx
- Posts: 5615
- Joined: Sun Oct 06, 2002 5:04 pm
Structure240sx wrote:compression test it. and your turbo has got to be shot. im very sorry to hear
Will do the comp test first, but I'm sure it's gonna be low.
How sure can one be that the turbo is shot? I checked it and it has the same shaft play as before, no propeller contact with the housing or anything. Maybe the seals are gone or something but I won't be sure until I fire up the engine, can I? Well I checked the compressor side, wasn't able to check the turbine.
ftrs13 wrote:maybe you got lucky with the turbohope the engine is ok
One can just hope, cross his fingers, dance the walla-walla and call on a witch doctor :P
Quote » clanking noise not good either, could you have a clog in the turbo line, becuase I would assume you were getting a pressure reading?? [/quote]
The stock lighty crappy thingy didn't light up, so maybe there was just some pressure... enough maybe to save my engine. That's why I'm buying an analog sending unit to monitor fuel pressure from now on. I was gonna do it ever since the turbo was put on, but oil leaks and other issues kept me from it.
-
:: orion ::
- Posts: 1483
- Joined: Fri May 23, 2003 4:40 pm
- Car: '96 240SX, with KA-T @ 12psi...
- Contact:
Turbo red hot is normal...think, your EGT are in the 1500-1600 F range...that'll get a cast iron turbine glowing red. I've seen my manifold, turbin, and the first 6" of my downpipe glowing orange under the hood - Do a long pull and then stop and pop the hood - You'll see.
No oil is no good, though...
- Brian
No oil is no good, though...
- Brian
Yes, but not like 5mins after the race, since that's about how long it took me to reach the parking lot and pop the hood. It's a first for me:: orion :: wrote:Turbo red hot is normal...think, your EGT are in the 1500-1600 F range...that'll get a cast iron turbine glowing red. I've seen my manifold, turbin, and the first 6" of my downpipe glowing orange under the hood
And neither when crusing down the highway at like 60km/hr in fifth... :pface Quote »No oil is no good, though...[/quote]
Yes... no oil is no good.
I'm gonna dive into my FSM later but how can I check if my oil pump is shot? Do I have to take it out? Or is there any other less labor intensive way?
I'm gonna see if I can borrow a comp tester from someone. Would the oil issues affect th compression test? I think I'll first solve the oil issues then do the comp test.
j-z wrote:so why did you even track your car knowing that you over boost going into third? thats your fault man.
But it rarely does it... it's one of those when-you-go-check-it-ain't-there problems. It only does it when I'm using the speed map setting on my SBC, and I'm thinking it has something to do with the Gain setting I'm using.
But yes... it's my fault. I should have run with the SBC off to play it safe... :rolleyes
ADAMHU wrote:yes the gain setting is very sensitive you should have it turned way down....
on my setup it doesn't matter i have the gain all the way up....at 14psi..it spikes to 19psi...before it settles down...
So maybe the 30-40 gain setting I'm using is a bit much? Ooops :pface
Adam, r u using auto or manual boost control? Cause I never could get the auto control to work.
SIMPLICITY owns
On my SR, I can touch the hotpipe coming from the turbo and it's not that hot. This is after a few minutes of hard running. My car runs rich and its an SR, but I thought it would be much hotter than it is.:: orion :: wrote:Turbo red hot is normal...think, your EGT are in the 1500-1600 F range...that'll get a cast iron turbine glowing red. I've seen my manifold, turbin, and the first 6" of my downpipe glowing orange under the hood - Do a long pull and then stop and pop the hood - You'll see.
- Brian
Point well taken. I actually found out when I was showing my car to a non-car friend and he touched the hot piped. I freaked out and told him not to touch that just as he made contact with it. I thought he'd be horribly burned...I guess the name "hot pipe" indicated him getting burned in my mind. He told me that it wasn't hot and then I touched it and found out that he was right. I figured it would be hotter than that...otherwise what's the point of having an intercooler? If I had to guess off the top of my head it only felt about 80 degree F...which was only a bit higher than ambient temps.
Def wrote:Hot pipe = Compressor outlet(intake air pressurized)
Exhaust manifold + turbo + downpipe = VERY hot exhaust
I wouldn't suggest you ever touch the turbine of your turbo after running it, as you might pull back with no fingerprints.
Lmao... If you cant tell that its going to be hot just by the heat jumping off of it, then you have issues.
My intake pipe gets so hot you cant touch it... Right after driving it for a while... I'ma get some wrap and wrap my manafold and downpipe, Maby even a turbo blanket... Anything to keep the heat down.
I cant belive your gain is so high!
I just got doen playing with my setup to hold 8psi better... I ended up with +33% from 6psi... (about 8psi) set the gain to 9 and my start at 7.0psi... (it sez to run your start at least 2.8 psi under the max psi... but this seems to work for mine with very little overshoot) I only overshoot to about 8.3 befor it nabs it back to 8.0...
The boost hits allot faster... I can tell it helped my car alot.
I've heard bad things about heat wrap, but this info is generally from domestic guys, who can be a bit, shall we say, stubborn and set in their ways.
I'm still a fan of new technology, especially when it's proven, so I'd suggest powder coating, but heat wrap is cheaper.
From what I can tell (just thinking about in the last 10 seconds) if the metal expands at a different rate than the heat wrap, you could have problems, but I still can't understand how cracked headers come about from using heat wrap.
BTW, you can do powder coating your self, do a goole search for DIY powdercoating. In fact, do a google search for DIY "anything" like anodizing or whatever, it's interesting to see what you can find.
Anyway, there are companies that make spray on powder coat for exhaust pieces, spray it on and the heat from the exhaust actually bakes the ceramic on. Cool stuff. Also, that'd keep under hood temps down, which will probably take the temp of your hot pipe down considerably.
I'm still a fan of new technology, especially when it's proven, so I'd suggest powder coating, but heat wrap is cheaper.
From what I can tell (just thinking about in the last 10 seconds) if the metal expands at a different rate than the heat wrap, you could have problems, but I still can't understand how cracked headers come about from using heat wrap.
BTW, you can do powder coating your self, do a goole search for DIY powdercoating. In fact, do a google search for DIY "anything" like anodizing or whatever, it's interesting to see what you can find.
Anyway, there are companies that make spray on powder coat for exhaust pieces, spray it on and the heat from the exhaust actually bakes the ceramic on. Cool stuff. Also, that'd keep under hood temps down, which will probably take the temp of your hot pipe down considerably.
Red-KAT wrote:I cant belive your gain is so high!
I just got doen playing with my setup to hold 8psi better... I ended up with +33% from 6psi... (about 8psi) set the gain to 9 and my start at 7.0psi... (it sez to run your start at least 2.8 psi under the max psi... but this seems to work for mine with very little overshoot) I only overshoot to about 8.3 befor it nabs it back to 8.0...
The boost hits allot faster... I can tell it helped my car alot.
Yes. Once my car is up and running and set the gain way lower and start experimenting. Haven't really given it much thought.. I just set the gain as high as I could without overshooting much.
Yep, it is cheaper. But my heat wrap is already crap. It falling off from having to work on my exhaust gaskets time and time again.Xero wrote:I'm still a fan of new technology, especially when it's proven, so I'd suggest powder coating, but heat wrap is cheaper.
Quote »BTW, you can do powder coating your self, do a goole search for DIY powdercoating. In fact, do a google search for DIY "anything" like anodizing or whatever, it's interesting to see what you can find.
Anyway, there are companies that make spray on powder coat for exhaust pieces, spray it on and the heat from the exhaust actually bakes the ceramic on. Cool stuff. Also, that'd keep under hood temps down, which will probably take the temp of your hot pipe down considerably. [/quote]I'll look into the DIY powder coating thingy. Might go with that insated of buying another heat wrap kit.