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Discussion Starter · #1 ·
Hi

How much will timing affect the ability of a jeep to start?

Well, more specifically...when I was having trouble with starting my jeep after warm I had someone look at it...they found it wasn't timed correctly...they timed it to 9 degrees out due to the fact that my carb was "pouring" gasoline down...he mentioned that it's supposed to be 5 degrees out...

Anywho...I replaced my carter with an MC...now it starts pretty hard...

Will the current timing of the engine account for the hard starting?

Thanks,
Patrick
 

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[ QUOTE ]
Hi

How much will timing affect the ability of a jeep to start?

Well, more specifically...when I was having trouble with starting my jeep after warm I had someone look at it...they found it wasn't timed correctly...they timed it to 9 degrees out due to the fact that my carb was "pouring" gasoline down...he mentioned that it's supposed to be 5 degrees out...

Anywho...I replaced my carter with an MC...now it starts pretty hard...

Will the current timing of the engine account for the hard starting?

Thanks,
Patrick

[/ QUOTE ]

Wow, interesting advice. ??

If it's to far advanced it will be harder to start but I don't thing 9* would be that much advanced that it would be hard to start.

"The fact that gas was pouring gasoline down" doesn't mean the timings off. I'm trying to think of a correlation.

Now to much fuel making a overly rich mixture on a warm engine will make it hard to start also. But that's a carb problem not a timming issue.
 

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Discussion Starter · #3 ·
Hi

I had the timing quite abit off when I took it in to him...

He said he timed it to 9 degrees out to help keep it running due to so much gas being dumped down...it was having a hard time running with 5 degrees out and the poorly adjusted/bad carb.

He did tell me its a carb problem but he doesn't work on carbs...said he would time it up correctly for me when I get the carb thing figured out...

So I replaced the problematic carter with an MC...just haven't had time to get the jeep back to the guy to have hime time it back up for me...

Thanks,
Patrick
 

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Advancing it slightly MIGHT help a little more than cleaning the inside of the brake light lenses, but then, maybe not.

Hard to start because of timing too far advanced it "bucks" or "kicks" - that starts at about 15+ degrees. 9 should be fine.

But - have a look at the plugs - being too rich for a long time they are probably sooty, robbing some of the spark.
They'll clean up in time, but best to toss new ones in.

After you put new plugs in, drive it on the freeway for a few miles - that'll get the rest of the soot out of the chambers. Driving it easy will just move the soot back onto the plugs again.

--------------------
I can't get over the competancy level of the folks that call themselves "mechanics." Ooops, "Technicians."

No wonder I had to hire 20 to find just 1 good enough to let him open a hood!


 

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So if it started before and you replaced the carb and now it does not like to start, Why not look at the carb? Does it have any vacuume leaks, are all the ports on the carb used or pluged? Does the choke work? Is the fuel leaking out of the float bowl? Look for the problem with what you changed that started the problem. Anyone of the things mentioned above will cause hard starting.
 

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You never told us what we are dealing with...
It it the same '82 CJ-7 you list in your bio?

If so, the '82 had the Motorcraft/DuraSpark ignition in it.
During cranking, the ignition retards 8° to 12° (depending on the module you have) and reverts back to the balancer reading when the key is in the 'Run' position.
 

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Discussion Starter · #7 ·
Hi

It is the CJ in the bio...

So during cranking it'll be 17-20 out?

Thanks
 

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[ QUOTE ]
So during cranking it'll be 17-20 out?

[/ QUOTE ]

That depends on what you mean by "out", Timing is Advanced or Retarded, not "out". Zero is when the #1 piston is at Top Dead Center (TDC) of the copression stroke. If the spark fires before zero it is Advanced, If after Zero it is Retarded. Base Spark for most production gas engines is 4 to 12 degrees advanced. (you need to lookup your exact spec.)

17-20 degrees Advanced is alot during starting. 17-20 degrees Redarded is always a lot. Or maybe you mean 17-20 degrees from spec?
 

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Discussion Starter · #9 ·
Hi

I'm pretty sure he timed it 9 degrees advanced...

More to the story...

So, I got it started this morning...was fairly happy...drove two blocks...left it running and ran inside to do something...came back out and stalled it pulling out from the curb (manual). It didn't want to start...so I left it there all day...

Thought maybe it was out of gas (gauge on E)...poured some gas in there this afternoon...it started...a little hard but started...seemed to run okay...took it on a little stroll down main street and out the highway...turned around and came back in town...

Had troubles coming out of a stop sign...felt like it was going to stall...then it shot like a gun out the exhaust and didn't stall...kept going...

Turned a corner and again...felt like it was going to stall , shot like a gun, then kept going...

Any more tips and advice you'd care to share, other than learn to drive... /ubbthreads/images/graemlins/grin.gif

Is this a timing issue or should I be looking at other things first?

Thanks
 

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exhaust explosion is too much gas not being burned, could be running way too rich, choke stuck, or just not firing on all cylinders

did you replace the spark plugs?

how are the plug wires...if you cant remember when they were changed last, your due for a tuneup/ubbthreads/images/graemlins/grin.gif

make sure the ignition is actually lighting the fire at all six and then check the carb...is it pouring gas in? even at significant rpms i havent seen my 232s' carb send enough gas for me personally to call it "pouring"

good luck
 

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Firing down through the exhaust is almost always ignition.

You need a timing light, and if you don't know how to use one, it's time for a trip to the garage.

Check the vacuum advance. Sounds like you may be having problems there.

Sometimes the outer ring of the harmonic balancer breaks loose and you can't set your timing correctly.

To learn to verify TDC (Top Dead Center) of the compression stroke, verify your harmonic balancer, and verify your distributor location...
Check here, http://www.junkyardgenius.com/ignition/dist01.html
 

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Discussion Starter · #12 ·
Hi

Can someone explain to me how the vacuum advance on the distributor is supposed to work...?

What type of vacuum should it be plugged into...port or manifold...?

Thanks,
Patrick
 

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There is a diaphragm in the vacuum advance canister.
When engine vacuum pulls on the diaphragm, the diaphragm compresses a return spring.

The diaphragm is connected to a rod that is in turn connected to a plate that has the ignition trigger on it.
That plate is free to move around the distributor shaft.

As the engine vacuum builds, the diaphragm will compress the spring and move the trigger around the distributor shaft IN THE OPPOSITE DIRECTION the shaft is traveling.

The effect this has is to effectively advance the ignition timing by having the trigger meet the shaft reluctor sooner.
--------------------------------

As for where to hook it up...

Vacuum advance should always be hooked up to the spark ported vacuum source on the carburetor.
The port location may vary depending on the type of carb you have.
 

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Discussion Starter · #14 ·
Hi

And vacuum advance really doesn't come into play at lower rpms right?

Here's my hypothesis...am I way off base?

I think timing is too far advanced...so spark goes off...but fuel still entering chamber...exhaust stroke pushes some fuel that came in after the spark into the exhaust...then something ingnites fuel in exhaust...

Now, what would ignite that fuel in the exhaust...hot gas being pushed through?

Why would there be ignition at slower speed rather that higher speeds? higher speeds push gas faster so a bit cool and not hot enough to ignite fuel?...or at higher rpm excess fuel is just pushed right out of system due to higher pressure of gas being pushed through?...

Or would fouled plugs be a better hypothesis...no spark so the fuel is just pushed though because it's not ignited due to lack of spark?

Am I making any sense or do I have some horrible misconception here and am over simplifying things?

Thanks,
Patrick
 

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I think you are speculating too much.

Back to basics:

Time it to about 8-10 initial advance at idle, vacuum disconnected.
Rev it slowly up while watching the timing - it should start advancong at about 1100 more and more to about 20-25 at 2500 RPM - vacuum still disconnected.

Connect vacuum - do it again, it should advance more than before until about 35 degrees at 2500.

If so, call it good.
Do that before anything else!

By your symptoms, it sounds like you have a weak ignition system, bad coil wire, bad coil, etc, causing misfire.
When it misfires enough, gas builds up in the exhaust and ignites - it's getting very hot gasses ejected from the cylinders all the time - at any speed.

Check to make sure you have the stock plugs the engine was designed to use - NOT AFTERMARKET TRASH. The engine was designed around plugs that were NOT multi electrode, splits, yellows, blues, platinums, or any other aftermarket junk made to get your money.
Just because the aftermarket book says it'll fit it doesn't mean it will work right. AC's or Champs only.
 

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Discussion Starter · #16 ·
Hi

I'll get it timed up...

What will I hear as I get it timed better?
Will rpms pick up...? Will sound be more consistant, no gurgling like a harley? etc...

I'll just tinker in the garage (just slightly turning the distributor, not pulling it out at all) with it and then take it to someone to get it spot on...the guy owes me one so...

I'm all about replacing 20+ year old parts putting new parts in and upgrading when I can...I'm not real good at fishing through pick and pulls to find things...I don't even know where a close you-pull-it is...

The closer to unbolt two bolts, remove part, insert new part, tighten bolts the better...I'm learning...slowly...

What are possible ignition upgrades (HEI?, TFI?, MSD?, TeamRush?)?

What are the ease of installations of each?

What are the costs associated with them?

Thanks!
Patrick
 

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[ QUOTE ]
Hi

Had troubles coming out of a stop sign...felt like it was going to stall...then it shot like a gun out the exhaust and didn't stall...kept going...

Turned a corner and again...felt like it was going to stall , shot like a gun, then kept going...

[/ QUOTE ]

If everything else checks out, check your float level.
 
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