Jacob Wilson

when we try to start it it turn for a bit then backfire quite spectacularly. I have checked the firing order from what I have found online, replaced distributor so now I have spark to all cylinders, we have looked at the timing to get it lined up, we are kinda stumped. any advice would be greatly appreciated.

MDchanic

Did you check the firing order in a counterclockwise direction?

Are you sure that when you installed the distributor, it wasn't 180° out?

Have you had the engine otherwise apart?

Why did you replace the distributor?

Welcome to ClassicOlds.

- Eric

coppercutlass

Sounds like it's 180 degrees off on timing. Make sure that the number 1 pistons is a tdc so have someone crank it and when you feel air pushing out then align your timing mark and you should be at tdc on the compression stroke. make sure that your distributor rotor inside the cap lines up with the number 1 on the cap which everone it maybe on your set up.

tru-blue 442

Pull #1 plug, have someone bump the starter
untill you have pressure, I like to use my index finger,
that will be your compression stroke.
Check the position of your roter. That will be #1.
Starting there go counterclockwise, 18436572, for
the firing order. Do the check with the coil wire off.

If that doesn't work, you may have jumped a tooth
on the timing gears. It the original engine? How many miles?

oldcutlass

What they said^^^^^^.

Jacob Wilson

it is the original engine, it has 73,000, I do not think that is correct though. I am hoping it is not the timing gear or chain, because when those fail, they fail quit thoroughly, and I do not have a way to get the engine out to get access to the timing gear

Jacob Wilson

it is the original engine, it has 73,000, I do not think that is correct though. I am hoping it is not the timing gear or chain, because when those fail, they fail quit thoroughly, and I do not have a way to get the engine out to get access to the timing gear

Jacob Wilson

we have checked the firing order many times.
No I am not sure about the distributor.
I had the heads off to find out why I had no compression
and because no spark was going to cylinders.

MDchanic

So what did you find was the cause of the lack of compression?

-- Oh, wait - you're the guy who found two bent valves.
Why did they bend?

You do not have to remove the motor to change the timing chain - only the accessories on the front.

- Eric

Jacob Wilson

we have no Idea why they were bent
and I want to exhaust all my other options before I go to timing chain, as that is likely one of the more unlikely possibilities, it was running when we got it.

joe_padavano

So let's back up. It was running when you got it. What happened when it stopped running? Why did you start replacing parts apparently at random? Did you do any troubleshooting first?

Please provide complete information if you want a useful response.

MDchanic

A V8 can run with two dead cylinders.

A bad timing chain can cause valves to bend (It's happened to me).

- Eric

Octania

Bent valves plus "no spark" to me adds up to all the teeth gone off the cam sprocket. This can easily be done in the driveway. A lot of steps, and a few special tools make it easier/ possible, but, it can be done.

Did you try observing the distributor rotation while cranking the engine?

If it's not turning and smoothly at that, then this needs to be addressed.

by the way it helps to include pertinent information like what has gone before. One easy way to do this is to post a link to related threads, such as this "lack of compression" thread, to make it easy for readers to get up to speed.

https://classicoldsmobile.com/forums...cylinders.html

"one of the more unlikely possibilities, it was running when we got it."
====================
I don't agree with that logic. Stuff breaks all the time. The time it dies vs. when you got it is unrelated, generally. Go back over the last things "fixed" - maybe list these in reverse order back to when it ran last.

Jacob Wilson

the only parts I have replaced are valves and distributor cap. yes it does run, I also forgot to say I have a holly carb, and edlbrock intake. both of which were on the car when I got it.

Jacob Wilson

the valve issue is delt which and I have compression in all cylinders. also spark is now in all cylinders with the new cap

Jacob Wilson

the distributor rotates very smoothly counterclockwise.

Jacob Wilson

thanks, I will take a look at the timing chain, and it could run, just not well or reliably

Octania

That pretty much leaves spark timing, initial [e.g. 180 degrees off] and/or wires going CW instead of the correct COUNTER-clockwise around the cap.

Do what is set forth in Post #4. Chances are that fixes it.

You realize that just setting the timing marks to TDC is not enough, right? You must make sure it's not 1 crank turn away from the proper spark time for #1 cylinder.

Jacob Wilson

http://www.youtube.com/watch?v=-PoH5...ature=youtu.be

my car lives, video of it living is up.
thanks to everyone who helped. also it doesn't run, it just starts then dies.

MDchanic

Are you getting power from the resistor wire to the coil, or only from the yellow wire from the starter solenoid to the coil?

- Eric

Jacob Wilson

I'm going to be replacing those , the wires have kind of melted a bit, so those are going to be replaced.

MDchanic

Jump from the battery (+) to the coil (+) and then see if it runs.

If so, you'll have to disconnect that wire to turn it off.

- Eric

Jacob Wilson

it does run just fine, the only major issue is wire from coil to starter kinda catches on fire. I am getting a beefier wire tomorrow to put there, then just going to tune. but it runs just fine now.

tru-blue 442

So was your dizzy timed wrong or what?
You got it figured out, but what did you do
to fix it?

MDchanic