I think my Jimmy died in a VERY bad way

[Nitrousbird]

95 GMC Jimmy 4-door 4x4, 4.3L CPI motor, 157k miles.

 

This truck has been pretty good to me, until today. Since it has gotten really cold out, when it is first started, it would take cranking 3-4 seconds before starting, then it would be fine. I'm sure it is ready for plugs, and I have them sitting here, but haven't done them yet. No biggie.

 

Today, I start her, and as usual, 3-4 seconds. Drive 5 minutes to Meijer, shop for over an hour, and come back out. Mind you, it ran fine the whole way to Meijer.

 

Crank 3-4 seconds, starts, but is running rough. Crappy idle, but when I take off, it has no power. Imagine trying to power that truck with a 20HP Briggs and Straton...THAT low on power. Temp is cold and oil pressure is good. I make it to the top of the Brice road overpass, and the truck stalls out.

 

Stop at the light, and I try to crank it. Click; but the kind of click you would have if the starter just can't turn the motor over. Battery guage is good. I end up pushing it w/ the g/f steering to the Home Depot lot, AAA tows me home.

 

Pull the dipstick, and the level is insanely high, like 5-6 quarts high! I changed the oil a week or so ago, and put the correct amount in AND checked the level. No foam, so I doubted coolant, lit it w/ a lighter, no crackling, so no water. But I take a wiff....whew, a STRONG smell of gasoline.

 

Now WTF would cause that?? I'm pretty sure the motor is locked up. I'm going to drain the oil tomorrow, pull the plugs, and pull/cut open the oil filter. My roomate had an over-the-phone guess that I put a hole in the piston.

 

I just can't get how the truck has been running fine, ran fine all the way to Meijer, then just all of a sudden does this.

 

If the motor is toast (probably is ), I guess I'll have to take a good look at the possibilty of doing a V8 swap. Being a 4x4, that may not be a realistic venture (either by cost or the work it will take). If not, in goes another 4.3L.......now I wish I hadn't sold my wrecked Blazer .

 

Any other things I should check before making a final determination?? I'll try to turn the motor by hand and see if that does it too; and pull the distributor cap to see if the rotor is turning if I can get the motor to turn.

[copperhead]

LMAO @ "I think my Jimmy died"

 

To swap in a small block, all you would need would be an upgraded radiator and electric fan, ignition and fuel pump. Assuming you go carbed.

 

Rebuild kits for 4.3's are rather cheap, and so are junkyard motors. I would rather suggest rebuilding what you have assuming it is salvagable, as more likely than not you'll just have to rebuild whatever you get unless it comes in a crate. Last I paid any attention (a good while ago) you get get a 4.3 rebuild kit from jegs with the hyperuetectic (sp?) pistons and all that for like $250.

 

As for troubleshooting the problem, wouldn't have a clue. I have a ways to go before I reach "mechanic" status.

[Guest 10secondMouse]

Possible the port injection took a shit, seen it on my buddy's 95 Blazer, loaded the crankcase with fuel and well... you know the rest of the story.

[Total Sign]

injectors could be really leaky, as your oil level grew.

 

check compression on all cylinders if you have a chance...

[Nitrousbird]

After lunch I'm going out there to pull the plugs and try to turn it over. If gas is going to come out, I'm sure I'll notice it there.

 

I'd love it to just be the injector unit, but I doubt I'm that lucky. It's not hard to do; I had the unit off when I had my 93.

[Nitrousbird]

Oh my, it is VERY bad

 

I first decided to pull the plugs (which could definately have been easier.....had to pull the wheel for the passenger side, and the #3 plug was a biatch). Gas on all the plugs, but definately no gas pouring out. I bump the starter; nothing.

 

From there, time to drain the oil pan.....VERY BAD[/url]. I estimate 6 quarts of clean coolant came out the bottom of the pan before oil started to flow in. I actually had to put the drain plug back in, because my catch pan can't hold that much coolant + oil!!

 

Yeah, you can say that motor is 100% toast.

[Ziggy1647545504]

That sucks. Maybe you'll be lucky and it's just a blown head gasket? Do some more teardown and let us know what it looks like.

[smokin5s]

Originally posted by CR Caddy:

That sucks. Maybe you'll be lucky and it's just a blown head gasket? Do some more teardown and let us know what it looks like.

I was gonna say, run a compression check on it... it might just be the head gasket.... although coolant in the oil pan doesn't sound like a head gasket.... but you never know.

[Nitrousbird]

Oh, it's gotta be more than a head gasket. A ton of gas/oil mix came out after the coolant (very strong gas smell, plus the oil was really thin). After draining all this, I tried to bump the motor again; still doesn't budge. Locked up motor + tons of coolant/gas in the oil = bad news. No reason to tear it down further while it is still in the truck; waste of my time.

 

Ahh, what a nice f'ing X-mas present. And looking at the reality of a V8 swap, maybe if I had some more cash and time I'd do it, but I just need the damn truck running again. What a freaking bummer.

[smokin5s]

are you going to rebuild this motor or go for a crate motor from somewhere? (crate might mean junkyard motor)

[Dave1647545494]

you need to regasket or replace the intake manifold its made of plastic and has most likely cracked.

 

your jimmy has one injector and the seals have gone bad cuasing it to leak down into the cylinders. coolant also goes throught he same area and if you drove it for a few miles it is entirely possible that you pumped almost all of the coolant into the crankcase.

 

nothing to be super panicked about its actually kind of a common problem on those motors

 

hope this helps

[TurboRust]

Originally posted by Gas, Grass, or Ass:

you need to regasket or replace the intake manifold its made of plastic and has most likely cracked.

 

your jimmy has one injector and the seals have gone bad cuasing it to leak down into the cylinders. coolant also goes throught he same area and if you drove it for a few miles it is entirely possible that you pumped almost all of the coolant into the crankcase.

 

nothing to be super panicked about its actually kind of a common problem on those motors

 

hope this helps

He beat me to it, we see one every few months at firestone with the same issue..not turning over=hydrolocked. Block may be ok, like he said tear apart the intake and check for cracks and go from there.

[Nitrousbird]

Both my upper and lower intake manifold are aluminum, not plastic. The fuel injecton unit (the central port injection unit) is a batch fire injector w/ 6 "poppets".

 

Cracked or not, the fact the motor won't turn after I dumped out all of the contents of the motor and took all the plugs out; if it doesn't budge now, how can I get it to break free?? I am still betting something internal is damaged on the motor, but I'm all ears to suggestions!!

[Buck531]

I heard something a while back that if you put "something" in the engine and let it sit, you can crank it over. Damnit, I can't remember what was said either.. grrr

[Trouble Maker]

Originally posted by Buck531:

I heard something a while back that if you put "something" in the engine and let it sit, you can crank it over. Damnit, I can't remember what was said either.. grrr

ATF.

[Guest aftermidnight]

head gasket for sure...my s-10 i used to have did the exact same thing. for some reason, i dorve it to work and it ran fine, but the temp was like -2 and when i went to leave, it started and made it about 2 miles and died. all the water was in the pan. my driver's side head gasket let go so i sold it. sorry to hear of your misfortune.

[Tractor]

Yeah you may not be in a bad of trouble as you think. On the trails we hydrolock engines all the time. We just change the oil out a few times and they run fine. If you drove it a long way doing this it may need a valve job, but the internal damage will only happen after you fix it. The bearings could rust and cause a connecting rod failure or something. I'd say fix the leaks and flush it a few times.

 

Evan

[grease monkey]

put a 1/2 in drive socket on the crank pulley, then get a nice big 1/2 drive ratchet, or breaker bar and turn the engine by hand with all of the spark plugs removed. when you turn it with the plugs out any liquid in the combustion chamber will be pushed out by the piston assuming that you can get the engine to turn.

[Boost-n-Juice]

Something went wrong which caused it to run extra rich, gas passing by the rings and then spinning the Mains. When it's real cold out and when things heat up it draws moisture. While it sat when you were in store one of your sensors or something probably became damp causing it to run like that. Sounds like it was pulling timing but dumping fuel at the same time. What's the latest?

[Nitrousbird]

I haven't touched it since dumping the coolant out of the motor and pulling the plugs. I was without electric for part of the time I could look at it, was out of town for several days, and bad weather my other days I could work on it. Hopefully I'll mess with it Wed. and Thurs. this week. I'll see if I can crank it over by hand; if so I'll pull the intake and then go from there.

[el aguila]

Originally posted by Tractor:

Yeah you may not be in a bad of trouble as you think. On the trails we hydrolock engines all the time. We just change the oil out a few times and they run fine. If you drove it a long way doing this it may need a valve job, but the internal damage will only happen after you fix it. The bearings could rust and cause a connecting rod failure or something. I'd say fix the leaks and flush it a few times.

 

Evan

There's no way you're "hydrolocking" the engine if it runs "after a few oil changes". Hydrolocking is exactly what it's name implies-lock.

[Guest AlpineFox]

I have a spare 4.3 tbi if you want it

[JaSSon]

Originally posted by el aguila:

There's no way you're "hydrolocking" the engine if it runs "after a few oil changes". Hydrolocking is exactly what it's name implies-lock.

Hydrolocking is exactly what it sounds like... a combustion chamber filled with some sort of liquid (gas, oil, water, coolant, kool-ade, whatever) If you're lucky, once you get that fluid out you'll be able to turn it over. If you're not lucky, then you probablly crushed a connecting rod. it's called hydro lock, not hydro-siezed.