97 blazer wont start

i just swapped my motor into my blazer, its the same 4.3 vortec. everything is connected, and we set the timing, or so we thought and tried cranking the motor over. it sparks here and there, turns over smothly, then stops all of a sudden, then jerks around a little bit, then continues turnin smothly. and that sequence is completely random. we thought we had it 180 off, so we corrected it, and it still just wont fire up. u can hear it combust, suck air in, back fire, everything but just start. all new wires, plugs.. rotor and cap is maybe 4 months old. i dont think im missing a sensor connection, that i know of. is there any connection that would prevent the motor from starting. the motor also sounds awful when it tries starting, nothing like it did with the old motor, almost like a smoker coughing. im gettin quite frusterated with this blazer, almost ready to give up. any help please?!

Are you trying to use the old vcm/ecm that was dunked in the pond (http://www.automotiveforums.com/vbulletin/showpost.php?p=4508754&postcount=8)?? Unless you have the vcm that was with the new engine it will have to be reprogramed.

as a matter of fact yes. im supprise you rememberd i did that. but that motor ran for 2-3 months before it blew up. so i figured the old ecm is fine. never showed any signs of problems

You need to get the ecm that was on the new engine. Unless both ecm's have the same numbers the engine won't even start. Are both engines the same year? If not you will probably need the wiring harness that was with the new engine.

the guy at the yard told me that it was the same year motor, how do i check this number on the ecm and motor?! i was not aware of this. wire harness seems to fit everything perfectly. now im startin to get a lil worried, how much does the typical yard charge for the ecm

. . . how much does the typical yard charge for the ecm
I got a vcm for my '95 for 40 bucks, but the price will probably depend on what part of the country you're in. The long set of numbers on the ecm's have to be the same, even then you won't get anything other than a start without reprogramming the ecm, as it has to be set up with the transmission, etc.

I don't have a book to check engine numbers, but as I recall there's a big article about engine types in the "How To/Tech Info" section of the FAQ's section of this Blazer forum.

i didnt think it would be a problem since they are both identical motors taken out of "supposedly" 97 ls blazers and its still the same tranny. everything is the same, i just never saw the vehicle. i guess im gonna give that a shot and take a look into it, anyone else have any ideas bout it? anyway to tripple check my timing?

Here's a link to the article (http://www.automotiveforums.com/vbulletin/showthread.php?t=534327)I was talking about, it gives the casting numbers for engines up through '98. Check the casting numbers on both your blocks, if the casting numbers are not the same, then they are different years.

The timing should not be adjustable on a '97, as that function is handled by info supplied to the ecm by the crankshaft sensor and the camshaft sensor. To set the time, bring #1 cylinder up on compression, align the timing marks on the damper pulley and put the distributor in with the rotor pointing towards #1 spark plug wire in the cap, or as close as you can get it to point to #1 spark plug, as it may point between #1 & #3 or between 5 & 1. Make sure you know which cylinder is #1.

thanks, i appreciate it lots. if this doesnt solve it, is there anything else i should know

The firing order is 1-6-5-4-3-2 - so, set your distributer with rotor pointing as close as possible to #1 in the cap. Make sure you have the spark plug wires on the right spark plugs as it's easy to get them on wrong.

http://img.villagephotos.com/p/2006-5/1178639/95-994.6WFiringOrder.jpg

thanks, i appreciate it lots. if this doesnt solve it, is there anything else i should know
There are actually two timing marks on the damper pulley ('98). When you are timing the engine, make sure to use the latter timing mark. If you use the other, engine won't start.

the latter one?! i know theres 2, but what one is the later one. after the compression? by buddy, who is also my mechanic, set it to top dead center, droped the dist in, and it still sounded like timing was off a bit. so we should use the other timing mark?

First mark is before TDC and the second one is TDC. When you rotate engine, don't use the first mark but the second. In TDC other mark is pointing 3 o'clock, not 12 o'clock. You can try both of those it doesn't harm the engine.

Hold up guys, it is a 1997, he needs to replace the ignition switch.

Hold up guys, it is a 1997, he needs to replace the ignition switch.
Maybe, but I doubt it at this point - he has a compatibility problem - probably should just divorce the whole thing. :wink:

oh boy, here we go again, you and your ignition switch. hahaha. no its not the ignition switch, ive replaced it 2 times on this thing. you and me have had this discussion again. allthough i was thinking about it! it ends up the timing is off 180. wow i feel like an idiot. i was really startin to worry bout the compatability issue. now she starts up and purrs like a tiger on steroids. ohh its soo nice to finally hear her run again. thank you for all your help guys! oh and bout divorcing the whole thing, i maybe not catholic, but i refuse to divorce, especially on something like this. hahah no offence :)

Good to hear you have it up and running. I love happy endings.

ok, not so fast, my happy ending isnt gettin so happy now.... everything is all and good, untill i floor it, i get this nasty vibration from under me, and i think its my tranny, i filled it with fluid. btw holy crap it takes alot. i bolted the tourqe converter up right, i think.. is there any way to do it wrong? i deff think its the tranny though, it just doesnt whip through gears like it used to... it also makes a loud roar when i floor it, but its the tranny i think that does that to. OMG I AM NEVER DOIN A MOTOR SWAP AGAIN!! and does anyone know what a ctk sensor is? i think that is what the obdII codes came up with. any input?!

Ok, put it in park and rev the engine up slowly up to 2500rpms.

If you get a strong vibration where the whole truck shakes then you have a bad torque convertor. Sometimes the weight will fall off or the convertor will be damaged during reinstalltion.

If everything is fine while in park while revving the engine, then check the u-joints on the drive shaft. Make sure the bolts on the u-joints are tight.

By the way, drive shafts are balanced and you're supposed to mark the u-joint when you take the drive shaft off, so you can put it back the same. So, as a last resort, unbolt the u-joint and turn the drive shaft 180 and bolt it back up - Good Luck and let us know.

i never touched the drive shaft, only the fwd one, but i never put that back on. i rev it in park and it seems fine. only does it when it has a load on it. i was thinkin the touqe converter. what weight is on it? like a balance weight? i remember when unbolting it something slightly heavy fell off and drilled me in the head, but i thought it was a bolt. couldnt find anything though... one of my friends said it sounded like a u joint to. but they seemed fine when the motor first blew up. but hey... im willin to try anything at this point. i got this far, why give up now right?

. . . i was thinkin the touqe converter. what weight is on it? like a balance weight? i remember when unbolting it something slightly heavy fell off and drilled me in the head, . .
It's like a wheel weight, but is flat and made of steel. Take a magnet and run over the area where you were working and see what comes up, unless the floor was swept and dumped.

ya already swept. oh well. i guess theres nothing i really can do bout that, but it doesnt shake in neutral.and today, yet another damper, either my waterpump went or the gasket for it. god i hope its the rtv i used on the gaskets. so much for thinkin playin it cheap is good enough. is there any easy way to remove the water pump, without takin the motor out. haha. im tempted to throw some explosives in the intake on this stupid thing. i guess tehres always little bugs after u swap a motor?

i just swapped my motor into my blazer, its the same 4.3 vortec. everything is connected, and we set the timing, or so we thought and tried cranking the motor over. it sparks here and there, turns over smothly, then stops all of a sudden, then jerks around a little bit, then continues turnin smothly. and that sequence is completely random. we thought we had it 180 off, so we corrected it, and it still just wont fire up. u can hear it combust, suck air in, back fire, everything but just start. all new wires, plugs.. rotor and cap is maybe 4 months old. i dont think im missing a sensor connection, that i know of. is there any connection that would prevent the motor from starting. the motor also sounds awful when it tries starting, nothing like it did with the old motor, almost like a smoker coughing. im gettin quite frusterated with this blazer, almost ready to give up. any help please?!

When you get it the engine TDC compression stroke point the dist rotor as shown in this picture.
http://files.automotiveforums.com/gallery/showphoto.php?photo=51302
If you try to point it to no one plug wire where it comes out of the cap it does not come out.
Crazy caps crossover every which way before the fire goes out of the top.
After you get it running you will need to set the camshaft retard setting with a scanner.

what scanner, and how do i set it

. . . is there any easy way to remove the water pump, without takin the motor out. . .
Basically, drain the radiator, drain the block, remove the radiator shroud, remove fan belt, disconnect radiator hoses, remove the fan and then remove the water pump.

Not a big deal, but you may need a special wrench if your fan blade only has one bolt holding it on. (I don’t know about a ’97, my ’95 has 4-5 bolts holding the fan and the fan clutch as a unit to the water pump)

what scanner, and how do i set it

You will need a engine data scanner capable of reading the camshaft offset degrees.
It will read them in - or + degrees. You need to get it at least 2 degrees -or + or a close to 0 - or +degrees as you can.
If it is over 3-5 degrees off the PCM/VCM may set a code on it.
What it does is center the dist rotor dead on with the spark wire terminal.
You will have to turn the dist to adjust it while watching the setting on the scanner.
It has nothing to do with dist timing which is controlled by crank sensor.
Good luck on it and other problems on it MT

ok i changed the gaskets. and i have no coolant problems anymore. but now back to my tranny, its sluggish on high rpms when it comes to the tranny. looses speed, vibrates, something is most deff wrong but i cant figure it out. it only vibrates when it gets up to around 3700 and up. im really affraid this problem is gonna fry my tranny.... and what is average oil pressure at idle, half throttle, and wot??

Have you checked the u-joints on the rear drive shaft since you sunk it in the pond??

You probably should start a new thread with vibration in the title.

no need for a new thread, i figured it out....:( clutch fan was bent upon installation... so its shakin everything. and that is what loosend the waterpump bolts and allowed the coolant to leak out. last night the damn waterpump was leaking again, so i went to take it off and the bolts were loose all over again. couldnt figure it out untill i started her back up and noticed the fan was shaking terribly. one last question, does anyone know if a water pump on a 95 2dr 4wd blazer is the same thing as a 97 4dr 4wd? got one of them layin around so i can swap it

Check the '97 water pump against the old gasket you took off. If all the holes line up it should work, unless the fan and fan clutch bolt on differently. Even then you probably could use the fan and clutch from the '97. Make sure it extends the same distance into the radiator shroud or you could have an overheating problem.

I'm surprised you didn't get a vibration from the fan when sitting still and only when on the road. Course, I guess the fan clutch doesn't let the fan run all the time.

ok new thread up