Blown Headgasket ????

[Big Hank]

Just trying to keep this simple.

rebuilt my engine. 600 miles later, blew my headgasket, car still ran fine enough to get it to the house, just couldn't get on the gas much,.

new headgasket, now the car wont start and wont build compression, i've checked the timing by complete tear down and rebuild 2 times, no doubt its correct, piston TDC and cams exactly were they need to be, but still no good.

Bascially, my question, have any of you blown a headgasket and torn up any other parts in the process, such as piston rings, or valves, I have personally not hear of it, but would assume that coolent pouring into a cyclinder would create enough steam to do some harm.

i know you guys want to know car, and details, but i don't have that much time to type all the crap out, so i just want to know, have you ever broken anything else when simply blowing a head gasket?

thanks for any help, Gene MJ

 

[Matthew Currie]

It would be pretty unusual for it to do that much damage, and even if it did do some, I wouldn't expect that it would keep the engine from developing compression or running at all, but that might depend on how many cylinders you have to start with. If it's a 4, and two are leaking, that might be enough for it not to start. It wouldn't be all that unusual, if it's an aluminum head, for the head itself to be warped or even cracked. I think that's a definite possibility if it blew the head gasket so soon after a rebuild.

First thing I think you need to do is address the compression issue - test and see if you and figure out where it's going.

 

[FUNKYTEE5]

Just trying to keep this simple.

rebuilt my engine. 600 miles later, blew my headgasket, car still ran fine enough to get it to the house, just couldn't get on the gas much,.

new headgasket, now the car wont start and wont build compression, i've checked the timing by complete tear down and rebuild 2 times, no doubt its correct, piston TDC and cams exactly were they need to be, but still no good.

Bascially, my question, have any of you blown a headgasket and torn up any other parts in the process, such as piston rings, or valves, I have personally not hear of it, but would assume that coolent pouring into a cyclinder would create enough steam to do some harm.

i know you guys want to know car, and details, but i don't have that much time to type all the crap out, so i just want to know, have you ever broken anything else when simply blowing a head gasket?

thanks for any help, Gene MJ

Have you done compression checks on all cylinders? Sounds fishy. . Something has got to be missing from the equation to be that big of a invisible problem About all a popped gasket could do is crack a head or block from getting too hot. Unless you ran the thing till it melted, which it doesn't sound like you did. I can't imagine that a large enough volume of coolant could enter the cylinder and do the hydrolock thing without the intake getting submerged. Sumptins missing, gotta be! Good Luck

FUNKYTEE5

 

[Big Hank]

OK, i will explain the situation, i do appreciate the opinions, I have basically checked and replaced every single sensor and ignition component on the car including the computer.

The Car:

1995 Dodge Neon DOHC 5 spd short ratio
HAHN Racecraft Stage 2 turbo system, w/ front mount intercooler.
No cat.
dynomax exhuast
turbo xs blow off valve
fidanza 6 lb flywheel
spec stage 3....6 puck clutch
afx bored throttle body
afx 6 lb underdrive pulley
accel 35 lb fuel injectors
JE low compression pistons +.020
ARP head studs
ARP rod studs
Eagle I-beam rods
Greddy pro-fec b, electronic boost controller
mopar valve springs and retainers


I drove the car sensible for the first 500 or so miles, I turned my boost pressure up from 8 to 18 which with these supporting mods is not unreasonable. I was under the impression that i had a very good headgasket(the performance shop had me believing this was a recomendation from the turbo kit supplier) well it turned out that i had one that was not even comparable to stock. So the headgasket blew out while under full boost, blowing the bottem off of my radiator, and blowing the usual cloud of white. I pulled over imedietley and shut the car off. got out, looked it over, decided it was onloy 2 minutes to my buddies place, drove the car, never hitting the gas hard, and it never blew any smoke, and it was able to maintain temp, so i assumed no boost meant no pumping water into the cylinders. I drove it there, no problems. I did the head gasket swap at his place and everything went flawless. I put the car back on the ground and no start. It will crank, get spark, get compression, and fuel pressure, but no ignition.

I don't understand how i can get all the requirements for an explosion, but it just wont start or backfire or do anything resembling ignition. I messed with the car for two weeks until i was totally over it, it has sat for a while now and i have started the process once again of figuring out the problem. I'm just about to the piont of trying to find an entire wiring harness and starting from there.

I feel like i know this car better then just about anyone, but an engine is an engine in many cases, so any suggestions are always great, even if i have probably heard them before.

I have been over this on the Neon forums, but that just turns into a bunch of ricers who just want to talk about nothing.

Sorry about the length, just so much work has been put into this thing, i am over it and need to finally get somewhere with hit.

Gene MJ
#435

 

[FUNKYTEE5]

OK, i will explain the situation, i do appreciate the opinions, I have basically checked and replaced every single sensor and ignition component on the car including the computer.

The Car:

1995 Dodge Neon DOHC 5 spd short ratio
HAHN Racecraft Stage 2 turbo system, w/ front mount intercooler.
No cat.
dynomax exhuast
turbo xs blow off valve
fidanza 6 lb flywheel
spec stage 3....6 puck clutch
afx bored throttle body
afx 6 lb underdrive pulley
accel 35 lb fuel injectors
JE low compression pistons +.020
ARP head studs
ARP rod studs
Eagle I-beam rods
Greddy pro-fec b, electronic boost controller
mopar valve springs and retainers


I drove the car sensible for the first 500 or so miles, I turned my boost pressure up from 8 to 18 which with these supporting mods is not unreasonable. I was under the impression that i had a very good headgasket(the performance shop had me believing this was a recomendation from the turbo kit supplier) well it turned out that i had one that was not even comparable to stock. So the headgasket blew out while under full boost, blowing the bottem off of my radiator, and blowing the usual cloud of white. I pulled over imedietley and shut the car off. got out, looked it over, decided it was onloy 2 minutes to my buddies place, drove the car, never hitting the gas hard, and it never blew any smoke, and it was able to maintain temp, so i assumed no boost meant no pumping water into the cylinders. I drove it there, no problems. I did the head gasket swap at his place and everything went flawless. I put the car back on the ground and no start. It will crank, get spark, get compression, and fuel pressure, but no ignition.

I don't understand how i can get all the requirements for an explosion, but it just wont start or backfire or do anything resembling ignition. I messed with the car for two weeks until i was totally over it, it has sat for a while now and i have started the process once again of figuring out the problem. I'm just about to the piont of trying to find an entire wiring harness and starting from there.

I feel like i know this car better then just about anyone, but an engine is an engine in many cases, so any suggestions are always great, even if i have probably heard them before.

I have been over this on the Neon forums, but that just turns into a bunch of ricers who just want to talk about nothing.

Sorry about the length, just so much work has been put into this thing, i am over it and need to finally get somewhere with hit.

Gene MJ
#435

Im just thinking out loud. Are the injectors are firing? You have fuel pressure, but is fuel getting into the cylinders? All 4 have good compression right? Cams in sync? Is the spark strong? Dunno what else unless sumptins unplugged somewhere? Good Luck.

FUNKYTEE5

 

[Matthew Currie]

Are you Absolutely, check-it-a-third-time sure that you got the cam timing right and that it isn't 180 degrees off? Or perhaps only something like a tooth or two off? I know you know, and I'm sure you checked, and yet sometimes you can be so familiar with a thing, and so sure of it, that you look right past it.

Funkytees brings up a good point - just because the injectors are firing doesn't mean any fuel is going through them. What happens if you give it a little snort of gas down its throat?

Have you run a timing light to see if the ignition is firing at the right point? Perhaps some electronic component in the ignition system got fried.

 

[FUNKYTEE5]

Are you Absolutely, check-it-a-third-time sure that you got the cam timing right and that it isn't 180 degrees off? Or perhaps only something like a tooth or two off? I know you know, and I'm sure you checked, and yet sometimes you can be so familiar with a thing, and so sure of it, that you look right past it.

Funkytees brings up a good point - just because the injectors are firing doesn't mean any fuel is going through them. What happens if you give it a little snort of gas down its throat?

Have you run a timing light to see if the ignition is firing at the right point? Perhaps some electronic component in the ignition system got fried.

I've had cam timing off by 1 tooth on a Mistubishi 4CYL it would only stumble a tiny bit with the distributor all the way over. Other than that it just cranked and cranked. I finally found that I was referencing the wrong mark on the head for cam sprocket alignment. Just another thought

FUNKYTEE5

 

[Big Hank]

ok, i looked at timing once again, its all correct, took off the valve cover, verified the cams hadn't some how turned indside the cam gears. also verified that piston 1 was at TDC when it was supposed to be. Also did a leak down test, So it has compression for sure,

The neon forum has givin me a great bit of advice, it is possible for me to get both spark and fuel, but only for the first second. the injectors will fire no matter what for 1 second, and the plug will spark for for 1 second, then if it doesn't get teh proper signal from the cam or crank sensors, it will use teh Auto Shut Down relay and not fire the coil pack or pulse teh injectors, so i will look into this with a test light on the coil pack. I would imagine this same thing could happen on any OBD II jeep also. but anyways, i'll try it and keep it posted just for the curious.

thanks for all suggestion,
Gene MJ
#435

 

[Matthew Currie]

Do post back, just to end the mystery. It sounds as if you've got a sensor out. On the Chrysler-era Jeeps (don't know about the Renix), a dead cam position sensor is an immediate no-start; you get no grace period. A dead crank position sensor is also a no-start for both Chrysler and Renix systems, because the CPU reads it initially to set the timing. That's why XJ's always crank over a few times before starting, even when in good health. It sounds as if the Neon starts first and asks later.

However, just on the unlikely off-chance that the Neon cam sensor resembles the XJ's, I will mention that when the cam sensor on my stepson's 93 went bad, and it wouldn't start, I was able to get it to start by turning the ignition on first, then unplugging and replugging the connector at the distributor. The engine made "booting-up" noises, and started. It wouldn't reboot again without the same procedure, but it did start that way. Silly as it seems, you might try something like that.