Just got back from the dyno
03-14-2008, 12:36 AM
#1
Just got back from the dyno I wish there was something positive I could post here, but the only thing positive is I was able to drive 100 miles back home 
On the whole way down there, it was running a little hot (220ish) but it didn't really overheat. Strange, so I checked the coolant and it was low. I think (or thought I should say) that the head may have been barely leaking, but just coming out of the side, and was not getting into the combustion chamber. So anyways, fill the coolant back up to put it on the dyno. Go to start it up and the fuel pressure wont go above 30~40psi. 
So I took the pump assembly out and switched the wires around and made the primary pump the secondary and vise versa. That worked and we were able to get full pressure back. Then I decided to just jumper the wires at the boost switch and run both pumps together anyways. Glen (my tuner) turned the timing way down so we could get the AFR where it needs to be before we start making horsepower. Well, first run it went WAAYYYYY lean, hesitated climbing up thru the RPMs- it was definitely running out of fuel. So the one pump was completely dead by this time I imagine. And on top of that, it was spewing coolant out from below! 
One of the guys that worked there offered to look at it from below while I drove the car on the dyno and see if he could spot where the leak was coming from. So he did and what he found was that pretty much all the coolant was coming from behind the drivers side motor mount. It was just gushing out from there. I got up under there and looked while he drove it and sure enough, it was like a small faucet just pouring out. It is hard to tell if the leak was coming from the block itself or from the head gasket since there is hardly any room to look around under there with the alternator and the blower blocking most of the view...
So with the fuel pump dying or dead and the leak, it was obviously not going to happen tonight. We put a can of stop leak in for good measure and topped the coolant back off and filled the overflow tank and I drove home. I stopped at a mcD's half way to refill, but it had not lost any coolant when I checked it. Or if it had, it must have taken some from the overflow tank because when I removed the cap, it was at the top. The temp never even got to 200 though the whole way back it was around 190.
But now the bad news is that I may have a cracked block (worse case scenario) Can't really tell right now until the engine comes out, but the engine does need to come out at the very least for a thorough inspection. This whole situation absolutely sucks. I've about had it with this crap. I'm to the point right now I don't even want to think about the car. It will most likely sit now for a while until I am motivated again to screw around with it. 
I am so mad because this shortblock has about 4000 miles on it if that from the whole year I have had it, and half the time it has been leaking coolant. I thought it was the head gaskets, but now that I've been through 2 sets of heads (first set was stock 6.0L heads that were brand new, and second set was the AFR's which I had milled to make sure they were perfectly flat) and also been thru 3 sets of gaskets, I'm starting to lean away from the head gasket theory. I'm really hoping it is something very simple like a freeze plug or something, but I'm never that lucky 
On the whole way down there, it was running a little hot (220ish) but it didn't really overheat. Strange, so I checked the coolant and it was low. I think (or thought I should say) that the head may have been barely leaking, but just coming out of the side, and was not getting into the combustion chamber. So anyways, fill the coolant back up to put it on the dyno. Go to start it up and the fuel pressure wont go above 30~40psi. So I took the pump assembly out and switched the wires around and made the primary pump the secondary and vise versa. That worked and we were able to get full pressure back. Then I decided to just jumper the wires at the boost switch and run both pumps together anyways. Glen (my tuner) turned the timing way down so we could get the AFR where it needs to be before we start making horsepower. Well, first run it went WAAYYYYY lean, hesitated climbing up thru the RPMs- it was definitely running out of fuel. So the one pump was completely dead by this time I imagine. And on top of that, it was spewing coolant out from below! One of the guys that worked there offered to look at it from below while I drove the car on the dyno and see if he could spot where the leak was coming from. So he did and what he found was that pretty much all the coolant was coming from behind the drivers side motor mount. It was just gushing out from there. I got up under there and looked while he drove it and sure enough, it was like a small faucet just pouring out. It is hard to tell if the leak was coming from the block itself or from the head gasket since there is hardly any room to look around under there with the alternator and the blower blocking most of the view...
So with the fuel pump dying or dead and the leak, it was obviously not going to happen tonight. We put a can of stop leak in for good measure and topped the coolant back off and filled the overflow tank and I drove home. I stopped at a mcD's half way to refill, but it had not lost any coolant when I checked it. Or if it had, it must have taken some from the overflow tank because when I removed the cap, it was at the top. The temp never even got to 200 though the whole way back it was around 190.
But now the bad news is that I may have a cracked block (worse case scenario)
Can't really tell right now until the engine comes out, but the engine does need to come out at the very least for a thorough inspection. This whole situation absolutely sucks. I've about had it with this crap. I'm to the point right now I don't even want to think about the car. It will most likely sit now for a while until I am motivated again to screw around with it. I am so mad because this shortblock has about 4000 miles on it if that from the whole year I have had it, and half the time it has been leaking coolant. I thought it was the head gaskets, but now that I've been through 2 sets of heads (first set was stock 6.0L heads that were brand new, and second set was the AFR's which I had milled to make sure they were perfectly flat) and also been thru 3 sets of gaskets, I'm starting to lean away from the head gasket theory. I'm really hoping it is something very simple like a freeze plug or something, but I'm never that lucky 
03-14-2008, 12:45 AM
#2
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Wow, Bummer. Sorry to hear about this. Sometimes you have to take a step back and walk away from the car for a while. It clears your head and often lead to a new found motivation to get the car running again.
Good luck!
Glenn
Good luck!
Glenn
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03-14-2008, 08:51 AM
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the top was kind of a pain. with all the maneuvering i had to do to get it over the steering rack, it seems the bottom would have been easier. good luck bro sucks to hear about your problems, i have a feeling i will have problems too once i get the car running
03-14-2008, 08:57 AM
#11
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That sucks, though fuel pumps are not a big deal, but the engine problem might be.
Honestly I would come up with a list of possible culprits and make sure it's not something simple like a leak in a line/hose or a messed up freeze plug. When you say pouring out I tend to think freeze plug, unless the head is bigtime lifted. If the head gasket was bigtime messed up the car be burning coolant, have that licorice smell, and some cyl's might be running crappy and the car might have some bigtime misfires.
Honestly I would come up with a list of possible culprits and make sure it's not something simple like a leak in a line/hose or a messed up freeze plug. When you say pouring out I tend to think freeze plug, unless the head is bigtime lifted. If the head gasket was bigtime messed up the car be burning coolant, have that licorice smell, and some cyl's might be running crappy and the car might have some bigtime misfires.
03-14-2008, 09:27 AM
#14
That sucks, though fuel pumps are not a big deal, but the engine problem might be.
Honestly I would come up with a list of possible culprits and make sure it's not something simple like a leak in a line/hose or a messed up freeze plug. When you say pouring out I tend to think freeze plug, unless the head is bigtime lifted. If the head gasket was bigtime messed up the car be burning coolant, have that licorice smell, and some cyl's might be running crappy and the car might have some bigtime misfires.
Honestly I would come up with a list of possible culprits and make sure it's not something simple like a leak in a line/hose or a messed up freeze plug. When you say pouring out I tend to think freeze plug, unless the head is bigtime lifted. If the head gasket was bigtime messed up the car be burning coolant, have that licorice smell, and some cyl's might be running crappy and the car might have some bigtime misfires.
