Crap!! Replaced Knock Sensors & Valve Cover Gaskets - Truck won't start!!!
- Thread starter denvermaxd
- Start date
LittleCaesar
New member
This happened to someone on Yotatech years ago, where he crossed the lines. If I remember correctly, his only fix was a “new” used engine.
denvermaxd
New member
Hopefully, all is well now
I'll wrap this up for any future T4R members who experience something similar:
I let it sit with the plugs out for about 36 hours (mostly because I was too busy to get back to it). After I put it all together again, it started right up. Quite a bit of white smoke poured from the exhaust for about 10 minutes while it idled.
After the white smoke had largely dissipated, I shut it down and changed the oil. Oil looked normal, like conventional oil would at 2,500+ miles since last change. Topped off the coolant, and this morning I drove it to work. No CEL, no rough running engine. In fact, it felt pretty peppy, and I chalk that up to cleaning the throttle body, which was really dirty with carbon build up.
So I guess the moral of the story is: Don't pull the top off without draining coolant. Don't swap the hoses at the throttle body. RTFM. But if you do, it doesn't mean you killed your truck.
Thanks for all your advice and guidance! Saved me a great deal of anguish and $$, as I didn't have to tow it to a mechanic.
I'll wrap this up for any future T4R members who experience something similar:
I let it sit with the plugs out for about 36 hours (mostly because I was too busy to get back to it). After I put it all together again, it started right up. Quite a bit of white smoke poured from the exhaust for about 10 minutes while it idled.
After the white smoke had largely dissipated, I shut it down and changed the oil. Oil looked normal, like conventional oil would at 2,500+ miles since last change. Topped off the coolant, and this morning I drove it to work. No CEL, no rough running engine. In fact, it felt pretty peppy, and I chalk that up to cleaning the throttle body, which was really dirty with carbon build up.
So I guess the moral of the story is: Don't pull the top off without draining coolant. Don't swap the hoses at the throttle body. RTFM. But if you do, it doesn't mean you killed your truck.
Thanks for all your advice and guidance! Saved me a great deal of anguish and $$, as I didn't have to tow it to a mechanic.
mtbtim
Elite Member
I'm happy to hear it looks like your survived this relatively unscathed. I don't understand the comment, "Don't pull the top off without draining the coolant." What top? Since you did the valve covers, I'm assuming you're talking about your supercharger? Why would you have to drain the coolant before removing your supercharger. Yeah, some coolant comes out of the hoses and throttle body but you DO NOT get coolant in your cylinders. But, if you accidentally put one of the coolant hoses on a vacuum nipple on the throttle body, yeah, you're going to get coolant where it shouldn't be.
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mtbtim
Elite Member
Could you please expand on your comment about not draining the coolant before pulling the intake. This has me more than a little confused. Why would you have to drain the engine of coolant before removing the supercharger?
denvermaxd
New member
Yeah, I'm not sure... That's why I said upthread "I had no idea this would dump coolant into the chamber. Still don't really understand the mechanics of this." I was responding to DeathCougar's comment "When you pulled the intake without draining the engine you let a TON of coolant down into the cylinders." but now I'm thinking he/she meant pulling the lower intake without draining the coolant, which would indeed let a crap ton of coolant gush out of the main pipe that you have to disconnect to pull the intake past the timing belt cover. I definitely didn't do that. However, when I first detached the supercharger, and lifted it up clear of the intake, I heard coolant pouring onto the garage floor from the back of the engine. I jumped down and grabbed a bucket and at that point spun the drain cock to empty the coolant from the radiator. It's possible that coolant was coming from the hoses that pass through the throttle body? Seemed like an awful lot of coolant for a little hose high up on the engine like that.
When I pulled the lower intake, the base of the intake was pretty rusty, and there was some standing water in there, maybe an inch (?) in the back most pocket of the intake. It was definitely water and not coolant. There was nothing in the front of the intake where the knock sensors were, which I noted because if there had been water/liquid there, I would have suspected it was the cause of my knock sensors failing. They were bone dry. Similarly, the two gaskets on the lower intake were dry.
Regarding the swapped hose on the throttle body: Would that produce enough liquid to hydrolock the engine on the first crank? I mean, the sequence of events was: I put all the hoses back on, filled the radiator, and basically within 5 minutes of filling the radiator I tried to crank the engine and it immediately locked. It went "wuh wuh" and then totally dead, and wouldn't even turn for the next hour or so. I just can't imagine enough coolant would have made it from the little hose high up on the throttle body down into the combustion chamber to hydrolock the engine in this scenario... that throttle body hose probably didn't even have coolant in it yet, as the water pump hadn't had a chance to pressurize the system. Plus, after pulling the plugs and letting it sit overnight, it DID start up in the morning, while the throttle body hose was still mis-configured. It just smoked like crazy.
So I'm assuming something other than my screwup with the throttle body hose was responsible for a significant amount of coolant in the cylinders. Hopefully someone with more knowledge can enlighten us all. I'd really like to know if I have to drain the coolant in the future before I remove the supercharger to change the oil or whatever.
mtbtim
Elite Member
The only coolant hoses related to the supercharger are connected to the throttle body. That's it. You can't get coolant in your cylinders by simply removing the throttle body and supercharger. The coolant that got into your cylinders had to come from the fact your hooked up a coolant line to a vacuum line. That's the only logical explanation that I can come up with.
denvermaxd
New member
That's what I assumed. But where did the coolant come from that was pooling on the ground on the passenger side of my truck, apparently originating near the transmission bell housing, immediately upon me lifting the supercharger off the intake? At that point, all the hoses from the throttle body had been disconnected for 20 minutes or more (I took the TB off first, set it aside, then started on the supercharger). As soon as I lifted the supercharger off the intake I could hear liquid pouring onto the ground. I was very surprised.
T4R2014
Elite Member
The coolant steam-cleaned your cylinders and valves. There's always a bright side right?
denvermaxd
New member
Oh, and I agree with this statement. Except, is it logical that the amount of coolant that could make its way from the throttle body to the cylinder on a system that had been drained and refilled could cause hydrolock on the first crank of the starter? I don't know, I'm asking. Prior to re-attaching the lower intake I was looking at the valves inside the port, and didn't notice any liquid or evidence of liquid on or in the intake valves. I ran a vacuum around the ports and actually blew compressed air in there just to make sure no debris had gotten past my towel plugs. This actually lends credence to your theory, that the liquid entered the cylinders after I reassembled. I think.
hwell:denvermaxd
New member
Right!
On the dark side, I seem to have lost 2 mpg on my daily commute... at least, according to my Scangauge.
mtbtim
Elite Member
I'm just as confused as you are. The only coolant line connections are to the throttle body. There's no coolant flowing through the supercharger. It's the same when you don't have a supercharger and you're pulling your plenums. There's no coolant flowing through the plenums.
Are you sure the coolant wasn't just pouring out of the throttle body as you tilted the supercharger? Or one of the coolant lines was jostled and started draining out more coolant?
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denvermaxd
New member
I guess it's possible. I would have thought I would have noticed a bunch of coolant down in the lower intake when I pulled it off. I was super paranoid about crap getting into the valve intake, so I think I would have noticed if a bunch of coolant was pooling there. Hell, maybe the coolant poured in a perfect stream straight into one of the exposed intake ports without splashing or spraying anywhere.
The more I think about it, the more unlikely it seems. You must be right, it must have all come from the swapped TB hoses. Still boggles my mind that enough coolant could go from there to the cylinder to hydrolock it on the very first crank.
AntleredRuin
New member
OK, reading through this thread again, what Tim mentioned must have been what happened, at least partially.
You started pulling the SC, then realized there was a coolant leak from the line to the TB, so you drained the rest of the coolant. Then, you finished pulling the SC. There was a puddle from that initial leak that was then accidentally dumped down the throat of the intake manifold once the SC was pulled off, and that's what initially hydrolocked you.
The swapped lines just added insult to injury as you kept cranking it. The vacuum lines obviously have vacuum, hence the name, so I wouldn't be surprised if they can suck up a large amount very quickly.
Per your MPG loss, I'd suggest changing your spark plugs. You said that you were kinda able to get it to start, by pumping the gas pedal, so there's no telling what kind of pressure was put on those plugs. I'd also try to see into the cylinders with the plugs removed to make sure there's not still a minute about of coolant in them.
You started pulling the SC, then realized there was a coolant leak from the line to the TB, so you drained the rest of the coolant. Then, you finished pulling the SC. There was a puddle from that initial leak that was then accidentally dumped down the throat of the intake manifold once the SC was pulled off, and that's what initially hydrolocked you.
The swapped lines just added insult to injury as you kept cranking it. The vacuum lines obviously have vacuum, hence the name, so I wouldn't be surprised if they can suck up a large amount very quickly.
Per your MPG loss, I'd suggest changing your spark plugs. You said that you were kinda able to get it to start, by pumping the gas pedal, so there's no telling what kind of pressure was put on those plugs. I'd also try to see into the cylinders with the plugs removed to make sure there's not still a minute about of coolant in them.
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