alright so ive used this forum before to figure out whats wrong with my blazer but never posted or even signed up but yeah im finding myself in need of help.
i have a 96 2w blazer ls with the 4.3
last november the engine was replaced with a 4.3 out of a 93 2w ls and ran decent but never like it was supposed to
since then it started acting up more and more and thanks to this site i found out that the distributor gear was badly worn with some of the teeth being as sharp as razors
ive replaced the distributor and rotor and the plugs havent gotten to the cap yet because i cant seem to find a ride out to autozone
anyways with all that in lou it wont start for any reason ive checked tdc 10 times checked all the plugs and other than the normal darkening from its firing theyre fine ive checked the timing tried the gas in the tb trick all to no avail after sitting for at least an hour it will try to fire once but then stop and start sounding like its trying to build up a backfire or it will backfire

pic of the new and old distributor gears

 

Sounds like the timing is still off. I do not remember where the timing marks are at, but search the forum and should be able to find the information.

 

I'm not sure about the year of your truck, so I am talking EDI timing here, but there are a couple of common mistakes that are made. First is placing the #1 & #3 spark plug wires in the wrong place on the distributor cap. They are reversed from what you would normally think with the #3 wire taking the forward most position on the driver's side. The second common mistake is not placing TDC on the compression stroke prior to installing the distributor. The exhaust stroke has TDC in the exact same position so it can be easy to place the distributor in 180 degrees out. This link takes you from scratch. https://blazerforum.com/forum/tech-a...-timing-24373/

Note that the rotor must be pointing at the pointer with the little number "6" when it is installed correctly. I know it looks like it is pointing around the #2 spark position. But if you turn the cap upside down and look in it, you will see how the contact for #1 spark is molded completely across to the other side of the cap from #1. Clear as mud?

EDIT: Duh...I just looked again at the name of your thread. Don't know if anything above would be helpful to you or not for a '94, with the exception of insuring you're at TDC on the compression stroke.

 

thanks for the replies and sorry guess i shoulda made it a little clearer i have been working on cars ever since i can remember and when the engine was swaped i did it myself.
anyways unsure of the timing but there are only 2 ways that the dist can properly go in thanks to the internal shank and if memory serves correctly the rotor is pointed towards the no. 2 spark wire on perfect tdc (not compression or exhausting) but after looking at the pic i posted more closely i remember noticing that the shank wasnt in the exact same posistion when i had the rotor bug pointing the same way not sure if maybe the dist gear might have been installed backwards at the factory or not but just a thought also got a dist cap earlier and am going to install it in a lil bit to try and rule out cross firing
also read and was told that the problem could be the pump not putting out enough pressure i considered this might be the problem, but for it to at least start before and not after wards kinda didnt seem like that was the probin my head) also im out of money and a test kit is like $25 plus tax at autozone so i was wondering if anyone knew if the part shops loaned the tester or not (i have autozone, advance, orileys, and napa here)

 

Any of those stores should have a fuel pressure test kit as a loaner. I'm not sure what you mean by "internal shank"? Is that referring to the male tab of the shaft that sets into the female tab of the shaft on the oil pump? If you are, that doesn't prevent you from installing the distributor in more than 2 ways. If the oil pump shaft down in the block moved a little (and as you know it turns very easily) you could not use that to determine the correct placement of the rotor. You could very easily be off a several degrees. It's a bit hard to follow your post as one long sentence....but if I understand it correctly, is it possible that the internal shaft is not installed exactly the same on aftermarket distributors? Don't know for sure...just a thought. All it does is turn the oil pump shaft and the oil pump doesn't care what position it is in. Just as long as the two shafts mate.

 

ok so got frustrated with it not statring and gave up for a day today decided to put the old distributor back in just fro s**ts and giggles and it started....any thoughts?

edit~ also when i first put it back in, it ran perfectly but after having my brother run me to autozone for new dist cap screws (lost 3, 2 from the old 1 from the new) and putting the screws in it started random missing like just like before...

 

Hopefully you got your problem fixed, I just wanted to come back to this post with something I learned today that might be of interest to anyone in the future. I bought a new oil pump and also a pump driveshaft. What I noticed when I compared the new driveshaft to the old is that the female portion was not in the same location as the old drive-shaft (it's around 90 degrees different). This refers to what I was saying above that you can't use the position of the pump driveshaft as the reference to determine that the distributor can only go in one of two ways (either right on, or 180 out). The oil pump as well as the driveshaft does not care where it is aligned, just as long as the male and female mate correctly. Obviously, we can't even seat the distributor if they do not. So my point is, as many of you reading this already know, is that unless all parts of the oil pump driveshaft stayed frozen in place after you removed the distributor, you can't use the drive-shaft to determine if you are putting the distributor in correctly or not. That shaft turns to easily and it could be off anywhere in the 360 circle. You must follow the correct procedures to install a distributor, which includes using a long screwdriver to turn the drive-shaft to where the distributor needs it to be. Not the other way around.

P.S. I could be confusing the reference to an "internal shank", and it has nothing to do with the oil pump drive-shaft. But either way, just a follow-up to what I was thinking and a tidbit of info for the "good of the order"