383 wont start...timing carb or combination+high engine pressure

[sext7366]

Ok my 383 has been sitting for a while now and I decided to start her up and get it out a little.  I guess it was already too long because I couldnt get it started.  I decided to change the plugs wires and fuel filter for good measure, but still nothing.  I messed with the carb a little and finally with a neighbors help and a can of starter fluid I got it started.  the problem is It takes a long time to get it started even still.  It will spit through the carb with an occasional flame, which seems to make me think timing.  Now the real problem...the distributor is turned as far clockwise as possible because the vacuum advance is touching the hoses running to the heater core.  The cam is a comp cam 230/236 duration, and the carb is a holley 770.  The funny thing is it was running fine when I parked it and I cant imagine what changed in the car, but by now everything has been messed with so I guess i'm just at a loss of what to do...any ideas of what to check or try?

Also ever since the motor was rebuilt it has a large amount of pressure when running.  With a new pcv valve, and a breather on the oil filler hole, there is oil that drips out of the breather from the pressure.  If you disconnect the breather hose, you can literally see what looks like steam from the motor.  It is actually hot air with small particles of oil in it. Is this related or a secondary issue.  Oh yeah the lobe seperation on the cam is 110 degrees if it matters, and the 383 has a single plane intake and headers.

[71383bee]

Are you still running on the old gas?  If its got any ethanol in it and no stabil its probably varnished the entire fuel system.  The carb is probably got some crud in it.

To get some timing back into the dizzy just advance the firing order one post.  I've done it before when I have run out of room to advance.  Obviously you'll need to re-time the motor anyways because shifting by a post will add or subtract A LOT of timing! 

[elacruze]

Ok, I'll be the one to say it.

Sounds like your motor is hammered. Take off the oil filter, cut the can off of it and see if there is any metal in there. If there is, you may have wasted the camshaft which would account for the backfiring and hard starting, along with loss of compression due to the cylinder walls being ground up by the metal.

That's the worst case. It's quite possible that you just got really bad ring seal on the break-in, or the piston rings are upside down, with the timing jacked up. Here's my order of things;

1. Cut open the oil filter. If clean, proceed to step 2. If full of metal, rebuild engine.
2. Find somebody with a leakdown tester and have them check all 8 cylinders. Confirm TDC with valve covers off. See #4.
3. Confirm that your timing marks have not shifted, and use a light to time it.
4. If you find all these things in order, check the camshaft timing marks to see they're correct.

[Cooter]

Just because that 383 Has a Little Crankcase pressure, does NOT mean the engine is toast. (Rings)..Take the oil cap off any newer car while running and you'll see the same thing...All it means is that it is trying to get rid of the crankcase Vapor...This is an old Wives tail that has spread through the ages like a wildfire. Think About it, If the rings were that bad, it would be blowing raw oil out the tailpipe...

Agreed, sounds like you are running that engine on the old gas and the timing will seem like it's advanced when your dealing with an octane rating of around 10...Fuel loses arouind 1 octane for every 2-3 weeks of setting..This usually isn't a problem on a driver that gets fresh fuel every 3 weeks or so...But trying to fire up a car on 2 Y/O fuel isn't gonna work...

[71383bee]

Just because that 383 Has a Little Crankcase pressure, does NOT mean the engine is toast. (Rings)..Take the oil cap off any newer car while running and you'll see the same thing...All it means is that it is trying to get rid of the crankcase Vapor...This is an old Wives tail that has spread through the ages like a wildfire. Think About it, If the rings were that bad, it would be blowing raw oil out the tailpipe...

Agreed, sounds like you are running that engine on the old gas and the timing will seem like it's advanced when your dealing with an octane rating of around 10...Fuel loses arouind 1 octane for every 2-3 weeks of setting..This usually isn't a problem on a driver that gets fresh fuel every 3 weeks or so...But trying to fire up a car on 2 Y/O fuel isn't gonna work...

I agree.  I don't quite believe from what he is saying that the engine is cashed...now if you keep running it this way that is another story.  I would imagine that virtually every exposed soft part and the fuel system needs to be gone through.  i.e. all of the soft vacuum lines, the rubber fuel lines, the pcv, and maybe the rad lines too should be done.  Sounds like the plugs and wired were switched which is a good idea. 

If it were me and the car sat for over a year with a tank of gas in it I would do the following:

1.  Siphon/drain the tank and dispose of the old gas
2.  Drop tank and inspect or just take it to a radiator shop to be boiled and cleaned or just get a new tank and sending unit if its really been sitting.
3.  blow out and clean the rear to front fuel lines or replace if really sitting.
4.  Replace all of the soft fuel lines.
5.  Inspect, disassemble and clean, or just replace the fuel pump...its cheap insurance in my book.
6.  Remove the carb, disassemble, and rebuild it with new gaskets...its not that hard to do really and you'll be assured that no sediment or fuel deposits are blocking any orifices or transition slots.  If this is too much at a minimum unscrew the mixture needles and spray carb cleaner in them. 
7.  Change plugs and wires and maybe cap and rotor if worn. 
8.  Drain oil and refill with new filter.
9.  Now if it really has been sitting I recommend pulling the dizzy and re-priming the oil system.  If its only a year or 2  at the most your probably are okay.  I you do this then you need to redo the timing.  Be sure to truly find the compression stroke and set the dizzy to fire on #1 with 10 degrees of advance. 
10.  Make sure to have a GOOD battery that is fully charged...not a borrowed tractor battery or something. 
11.  Then with a squirt bottle full of gas prime the carb with fuel by pouring down the bowl vent. 
12.  NOW!  start the car...if everything is done right and the wiring is good it should catch and fire on the first few turns.  If not there may be other issues.

I have had friends do most of these steps on dormant motors and you'll be amazed to see that beauty come to life.  However, keep in mind that a lot of times there may be a good reason that the car has not ran for a long time...and that is it was running poorly to begin with so it may be beyond just bad gas sometimes.