The strangest thing happened while replacing a fuel injector...

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rkern
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Well I used Fuzzycats site to do a fuel injector replacement and when I finally got everything put back together (it was the number 2 injector) - the engine won't turn over. It's like the transmission is jammed, as the starter wants to turn but is stuck. What could possibly have caused this?

Note, I put everything back but the throttle cable cover before trying to fire it up. Any clue what could cause this? I can't imagine a drive train problem when I just popped one of the injectors out.


DAEDALUS
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The cylinder could be hydrolocked. When you pulled the injector out whatever was in the rail dumped into the cylinder. If it didn't have enough time to leak down into the crankcase, then it could jam the piston.Hope that's NOT it, though, as there's a risk of bending the rod.

rkern
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There was a lot of gas that dumped into the injector once it was pulled, and it kept coming - as it was overflowing onto the ground. Do I yank the injector and let the gas all run out (everywhere)? Or is this now something I go get towed?

I put the new injector in - in part to keep the gas from overflowing so I would bet your guess is correct. What's my next move?

DAEDALUS
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Hard to say with this one. It comes down to how strong your starter is relative to your conrod. I'll remain hopeful though--it's not like you were going 40mph and sucked up a bunch of water at 1300 RPM.I'd try a few more things before taking it to the shop. The gas should leak down oveernight on it's own (you'll need to change the oil in the morning). Just in case, I would also pull out the #2 spark plug tonight if possible. In the morning, change the oil--there'll be a lot of gas in it and you could have an extra quart in there. Pull the fuel injector fuse and, with the spark plug still out, crank it over a few times. Make sure it spins freely and all the gas is out of there. Replace the spark plug and the fuse, then see if it'll fire up. As an extra measure of peace of mind, you might want to turn the crank by hand first before attemptig to fire it up. Check for anything binding. Put a socket on the crank bolt and turn with a ratchet.

Q45tech
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Not strange at all! Common way newbies and less than expert technicans BENT rods and get to rebuild engines. 55 cc of gasoline [1/10th of a pint ~~ couple of ounces] is more than enough........as gasoline like all liquids is not compressible.

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Jesda
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So to prevent this, you need to pull the fuel line coming out of the fuel filter, then let the vehicle sit for a while, correct?

rkern
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I'll give this a shot. The bad news is, the battery was weak so I charged it to give extra power to crank it over - but by that time it was stuck already. We'll see but it appears luck isn't on my side for this. Thanks for all your help - it is appreciated.
Modified by rkern at 6:09 PM 1/31/2005

Q45tech
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Pulling the inlet fuel line is one way [after you have run the engine to exhaustion with the fuel pump fuse removed] but the returnline line may backflow and the rail still has some volume.

Why we almost always pull the plenum off and the fuel rail as a unit [to the bench] for replacement of parts [injectors, o-rings, hoses].

Saving a labor buck with individual on the car injector replacements is dangerous and tricky. If one is bad the others are usually impaired.

Fuel flow is 8,6,4,2 [rubber hose across front then] 1,3,5,7 to FPR then return to tank.


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metaverse3
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Remove all the plugs out of the spark plug hole and let it sit overnight.. If you do crank, crank without the plugs in place.

Did you follow the FSM procedure to drain the fuel system ? Take out the fuel injector fuse, run the car until it dies.. Keep on cranking a couple of times until it sputters. There will still be some fuel in the system after all this is carried out..but not to the level of hyrdrolocking the system...

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elwesso
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I got an idea, how about throw a match down there

Seriously, if you take out hte plug, maybe you can put a long straw down there or something like that and sort of suck out the gas.... Or at least turn it over with the plug out......

Hopefully no damage has been done!!!

rkern
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Quote »Did you follow the FSM procedure to drain the fuel system ? Take out the fuel injector fuse, run the car until it dies.. Keep on cranking a couple of times until it sputters. There will still be some fuel in the system after all this is carried out..but not to the level of hyrdrolocking the system...[/quote]I did follow the instructions that the individual had on the fuzzycats site - namely run the engine and then pull the fuel pump/injector fuses. Plus it sat for a week or so before I finally got the injector out. I can pull the plug and siphon any gas until that piston is dry which shouldn't be a big deal, I'm just worried that I put too much torque on the rod from the starter.

Unfortunately the write-up at the fuzzycats site never mentioned this as a possible risk, and unfortunately for me, it was the first injector I've ever tried to replace. We'll see, but if nothing else, I have learned (albeit the hard way).

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PoorManQ45
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The starter must have quite a bit of torque to beable to bend one of the rods

Quote »Did you follow the FSM procedure to drain the fuel system ? Take out the fuel injector fuse, run the car until it dies.. Keep on cranking a couple of times until it sputters.[/quote]Unfortunately I didn't do that before taking the plenum off. I found out the hard way that with pressure still in the lines, cutting one of them will create a siphon and completely empty the gas tank if left alone. You can just remove the gas cap to relieve the pressure also

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elwesso
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PoorManQ45 wrote:
Unfortunately I didn't do that before taking the plenum off. I found out the hard way that with pressure still in the lines, cutting one of them will create a siphon and completely empty the gas tank if left alone. You can just remove the gas cap to relieve the pressure also
No, you must do the fuel pump fuse AND remove the gas cap (remove the cap FIRST!!!)

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sijoko
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I had a problem with hydrolock once. This is how I took care of it. I pulled the fuse for the fuel pump. Then removed the sparkplugs. Put some rags over the plug holes. Then cranked the engine over to force the liquid out. Make sure you rest the starter so as not burn it out.

This procedure should get most of the stuff out. Then just leave the vehicle alone for a day or two for the remaining fuel to evaporate.

In my case, it was throttle body cleaner. I sprayed a little too much with the engine off and it flowed into an open cylinder.

-sijoko

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Q451990
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Bet you didn't have any carbon issues in that cylinder

rkern
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nm - duplicate post deleted


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