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-   -   86 Scottsdale - No start (https://67-72chevytrucks.com/vboard/showthread.php?t=814922)

BAChevyMan 11-25-2020 08:55 PM

86 Scottsdale - No start
 
I am a mechanic, but I never learned on these classics. All I do is newer stuff. School didn't even talk about carburetors. I had a recent no start issue on this truck once, but my nephew was over and I started the truck and it was running, but it was still trying to catch up from being started when he hit the gas pedal and snuffed out the engine... haven't gotten it to start since.

Things that are new, coil, cap, rotor, IGN module.

Apparently this engine was rebuilt 3 years ago and then parked, has an edlebrock 1407 carb with electronic choke and intake. Starting fluid don't help at all, if I crank long enough I can see the gas coming out the tail pipe, it has spark. While cranking it it sounds like its trying to catch, if I hold the accelerator to the floor it almost starts. I increased the idle and leaned out the fuel mixture to try to get it to start. Fuel pressure was recently tested and found to be good, and yes it does have gas.

My thoughts are its flooded, and/or cylinder walls washed from so much trying to start. But before I pull the spark plugs out and do a compression check I was just wondering if anyone had any ideas on getting this thing started?

geezer#99 11-25-2020 09:56 PM

Re: 86 Scottsdale - No start
 
Fuel pressure ‘good’!
What psi?

BAChevyMan 11-25-2020 10:06 PM

Re: 86 Scottsdale - No start
 
Quote:

Originally Posted by geezer#99 (Post 8840925)
Fuel pressure ‘good’!
What psi?

Edelbrock says to install a fuel pressure regulator and set it to 6psi, I don't remember what it actually was but I believe it was higher... like 8psi. And its been running at that fuel pressure since September. The truck is driven every weekend. If the issue was fuel pressure then a can of starting fluid or the gas I have dumped into the carb would have at least tried to fire.

geezer#99 11-25-2020 10:14 PM

Re: 86 Scottsdale - No start
 
Edelbrock is wrong.
5 psi max.
Maybe you got a needle dropped out of the seat. Or trash in it.
To get it started put pedal to the metal and hold the choke wide open.
Of course that’s after you drain and change the oil. Those gas fumes make big booms in the pan.

BAChevyMan 11-25-2020 10:27 PM

Re: 86 Scottsdale - No start
 
Quote:

Originally Posted by geezer#99 (Post 8840932)
Edelbrock is wrong.
5 psi max.
Maybe you got a needle dropped out of the seat. Or trash in it.
To get it started put pedal to the metal and hold the choke wide open.
Of course that’s after you drain and change the oil. Those gas fumes make big booms in the pan.

Wrong they may be but it ran that way before, I didn't change the oil but, Choke is electronic so I had my wife try to start it while holding the choke and throttle open... it tried to catch like 5 or 6 times but after that it just kept turning over like it had no spark.

geezer#99 11-25-2020 10:33 PM

Re: 86 Scottsdale - No start
 
So check for spark!
And then go thru the process of retiming it.

BAChevyMan 11-25-2020 10:51 PM

Re: 86 Scottsdale - No start
 
Quote:

Originally Posted by geezer#99 (Post 8840943)
So check for spark!
And then go thru the process of retiming it.

As I stated in the original post. It has spark. As I have been trying to start it my timing light has been on and flashes at me as expected. The closest it gets to starting is with the choke closed and the accelerator to the floor. I can check timing tomorrow maybe, but on a rebuilt engine, that has been running fine for 200+ miles without problems... doesn't feel like timing to me. In another note this may or may not be related, last time I drove it to Portland, Or from Salem (Bout 40 Miles) it did just randomly die while driving 70 mph. Pulled over to the side of the road and it fired right up and away I went without a problem.

geezer#99 11-25-2020 11:07 PM

Re: 86 Scottsdale - No start
 
A slightly loose distributor will rotate clockwise(retarded) over time.
Your excess fuel says pop the lid on the carb. Check needle/seat and float levels.

Dead Parrot 11-26-2020 07:33 AM

Re: 86 Scottsdale - No start
 
Pull a couple of the 'easy to get to' plugs and inspect. If they are still wet with gas after sitting overnight, you have found your problem. Verify the gap is set to .045.

If you manually operate the throttle while looking down the carb, you should see gas squirt into the openings. This is from the accelerator pump and is a quick test for "Gas in the Carb". This is a NOT while cranking test.

2nd the thought that this current problem sounds like a timing issue. It doesn't take much slippage of the distributor to go from running nice to no start. Another quick test - can you move the distributor as it sits, without loosening anything? You shouldn't be able to.

If you do plan on opening the carb, get one of the gaskets for the top in case you damage the one on there during your inspections. While the top is off, check the jet sizes so you will know what is in there for later tuning efforts.

Download the manual for that carb and read up on setting the float levels. They are often wrong out of the box. Too high a level can lead to flooding.

cadillac_al 11-26-2020 08:36 AM

Re: 86 Scottsdale - No start
 
There aren't many mechanics left nowadays. Most shops just have auto techs that read codes and replace parts. Dead Parrots instructions will solve your problem. If the plugs have drowned, they will most likely have to be changed.

Eyegore 11-26-2020 11:42 AM

Re: 86 Scottsdale - No start
 
If it was rebuilt, could the distributor be off 180 degrees? Had this happen last rebuild I did.

geezer#99 11-26-2020 01:08 PM

Re: 86 Scottsdale - No start
 
Quote:

Originally Posted by Eyegore (Post 8841131)
If it was rebuilt, could the distributor be off 180 degrees? Had this happen last rebuild I did.

It can’t run if it’s 180 out.

geezer#99 11-26-2020 01:12 PM

Re: 86 Scottsdale - No start
 
Another thought!
Your 200+ mile rebuilt.
Did you do a proper cam break in on it?

BAChevyMan 11-26-2020 01:57 PM

Re: 86 Scottsdale - No start
 
Quote:

Originally Posted by Dead Parrot (Post 8841024)
Pull a couple of the 'easy to get to' plugs and inspect. If they are still wet with gas after sitting overnight, you have found your problem. Verify the gap is set to .045.

If you manually operate the throttle while looking down the carb, you should see gas squirt into the openings. This is from the accelerator pump and is a quick test for "Gas in the Carb". This is a NOT while cranking test.

2nd the thought that this current problem sounds like a timing issue. It doesn't take much slippage of the distributor to go from running nice to no start. Another quick test - can you move the distributor as it sits, without loosening anything? You shouldn't be able to.

If you do plan on opening the carb, get one of the gaskets for the top in case you damage the one on there during your inspections. While the top is off, check the jet sizes so you will know what is in there for later tuning efforts.

Download the manual for that carb and read up on setting the float levels. They are often wrong out of the box. Too high a level can lead to flooding.

Spark plugs are new and I gapped them when I installed them. Pulled 4 of the spark plugs, tips are all black but dry and don't smell fuel fouled.

There is absolutely no concern of a gas issue, if I crank long enough I see clouds of unburnt fuel coming out the exhaust. Also if it was a fuel issue then starting fluid or gas that I have dumped into the carb would have at least made the thing run for a second.

I can agree that this sounds like a timing issue, or a no compression issue. And I would be more accepting of that if it wasn't for the fact of it starting and running driving down the road the weekend before.

Tried turning the distributor, that thing don't move at all.

I have had that carb apart about 8 times, I have checked the float level I forget the size but its something like using a 3/8 or 5/8 drill bit to check it. And if it is any incite to the skill of the previous mechanic. I got the tune kit for my carb, went to re-jet it. once I put the new metering rods in I noticed the lid wouldn't pop down with the metering rods in. I had to remove them and install them after the lid was on. Then looking at the metering rods that came out of the carb... they were bent.

Quote:

Originally Posted by cadillac_al (Post 8841031)
There aren't many mechanics left nowadays. Most shops just have auto techs that read codes and replace parts. Dead Parrots instructions will solve your problem. If the plugs have drowned, they will most likely have to be changed.

Yeah I agree I worked with a mechanic fresh out of school that was diagnosing a hesitation on acceleration (as in accelerating to pass). He checked codes, found none, told them to just not do that. My boss don't test crap either, he charged a customer to rebuild the abs module (without first checking DTC's) because the vehicle disabled the traction control, it came back, based on codes he charged them for a throttle body, turned out to be coils, since cylinder misfires will disable traction control. I try to not be that way.

Quote:

Originally Posted by Eyegore (Post 8841131)
If it was rebuilt, could the distributor be off 180 degrees? Had this happen last rebuild I did.

I agree with geezer, it wont run 180 out, also be a little strange if hitting the accelerator while it was running made the distributor spin 180 degrees.

Quote:

Originally Posted by geezer#99 (Post 8841176)
Another thought!
Your 200+ mile rebuilt.
Did you do a proper cam break in on it?

So, this wasn't my rebuild, because I have bigger plans for this engine in a rebuild. I have no idea what they did or who did it or anything. All I know is that they told me they rebuilt the engine 3 years ago, and apparently parked it I changed the oil when I got it. The 200+ miles is just what I have driven it. alot of around town two trips to Portland (40mi) two or 3 trips to mill city (30mi), a trip to Jefferson (20mi) all approximate mileages. My point is more indicating this truck is drivable.

BAChevyMan 11-26-2020 02:32 PM

Re: 86 Scottsdale - No start
 
Ok, here is a video of an attempt to start, with my timing light. Before y'all comment about how the timing light don't fire all the time... it dont matter how I connect this timing light, the battery, alternator, or anything. Its a side post battery and I can never get a solid connection. When adjusting the carb I was using the timing light to set the RPM. The only way I can get this timing light to be 100% effective is to attach the timing light to the battery of my car. But I slowed down the video and it does look like it has jumped time by the picture.


https://photos.app.goo.gl/3YpobCVEoHeqVadt9
https://photos.app.goo.gl/Gq2Gs8wVDYzHobbe6
https://photos.app.goo.gl/eZUBYMeu5CtK2BGP7
https://photos.app.goo.gl/oLYa8hQw3rzcxSVy8
https://photos.app.goo.gl/YsWoRJYZG2nxkWa46

Palf70Step 11-26-2020 04:06 PM

Re: 86 Scottsdale - No start
 
I have done it many times, but did the plug wires get put back in the correct firing order? I have caught myself several (well many) times do a dumb butt move when replacing cap or wires.

The only other thing that comes to mind is since you don't know about the so called rebuild, maybe time chain slipped a tooth or is loose.

I'd start from basics, get engine set to TDC and then check wires and all.

geezer#99 11-26-2020 05:37 PM

Re: 86 Scottsdale - No start
 
Like I mentioned before.
When in doubt, start over.
Re-time the motor just like you would with a fresh rebuild.

BAChevyMan 11-26-2020 06:21 PM

Re: 86 Scottsdale - No start
 
Quote:

Originally Posted by Palf70Step (Post 8841264)
I have done it many times, but is the plug wires get put back in the correct firing order? I have caught myself several (well many) times do a dun butt move when replacing cap or wires.

The only other thing that comes to mind is since you don't know about the so called rebuild, maybe time chain slipped a tooth or is loose.

I'd start from basics, gte engine set to TDC and then check wires and all.

The problem with that, is nothing has changed between now and the last time the engine was running.


Quote:

Originally Posted by geezer#99 (Post 8841287)
Like I mentioned before.
When in doubt, start over.
Re-time the motor just like you would with a fresh rebuild.

Yeah, well until I saw what I saw with my timing light I didn't want to admit that. Still hard to accept since it was just running last week. Its only 3.7 hours to set the timing... I'll probably have to.

truckin 79 11-26-2020 07:56 PM

Re: 86 Scottsdale - No start
 
Sounds like carb is running rich, probably junk between needle and seat

Dead Parrot 11-26-2020 07:58 PM

Re: 86 Scottsdale - No start
 
The black plugs support the too much fuel issue. Not being able to turn the distributor suggests it didn't suddenly change time by rotating.

Since you know the jet/rod combo in the carb, check the manual. It should have a tuning chart. Possible the PO set things too rich. I don't see that causing the sudden no run issue but nice to know once you get it running again.

Turn the idle mix screws in until lightly snug and back out a half turn. Normal is 1.5 turns IIRC. Since it is too rich, this might help until the real problem is found. Just remember to return to normal once things are working.

Hate to think it but wondering if something in the timing gear/chain setup has come loose and let things move. Worked on a friend's car many years ago that suddenly wouldn't start. It almost would. Turned out the timing chain had enough miles that it had stretched enough to let it jump a couple of teeth on one of the timing gears.

Might pull and check the distributor gear. Some newer cams want a certain kind of distributor gear or bad juju happens. I haven't built one like that so maybe someone will chime in with better info.

With everything dry, try the following test. Choke full open. Don't pump it. Just drop a few drops of gas into each front barrel and then crank. It should fire or almost fire for a second or two.

Another thought is maybe something inside the distributor came loose.

BAChevyMan 11-26-2020 08:44 PM

Re: 86 Scottsdale - No start
 
Quote:

Originally Posted by Dead Parrot (Post 8841348)
The black plugs support the too much fuel issue. Not being able to turn the distributor suggests it didn't suddenly change time by rotating.

Since you know the jet/rod combo in the carb, check the manual. It should have a tuning chart. Possible the PO set things too rich. I don't see that causing the sudden no run issue but nice to know once you get it running again.

Turn the idle mix screws in until lightly snug and back out a half turn. Normal is 1.5 turns IIRC. Since it is too rich, this might help until the real problem is found. Just remember to return to normal once things are working.

Hate to think it but wondering if something in the timing gear/chain setup has come loose and let things move. Worked on a friend's car many years ago that suddenly wouldn't start. It almost would. Turned out the timing chain had enough miles that it had stretched enough to let it jump a couple of teeth on one of the timing gears.

Might pull and check the distributor gear. Some newer cams want a certain kind of distributor gear or bad juju happens. I haven't built one like that so maybe someone will chime in with better info.

With everything dry, try the following test. Choke full open. Don't pump it. Just drop a few drops of gas into each front barrel and then crank. It should fire or almost fire for a second or two.

Another thought is maybe something inside the distributor came loose.

A lot of good points here some already attempted. I do know the jet combination because I have the tune kit and I have installed different jets. Before I did this the truck would blow black clouds at idle. But the last person to open this carburetor bent the metering valves. Its jetted at a 2 from Edlebrocks tuning chat. That stopped the black clouds.

Also I did try to reset the idle screws. I reverted to stock for Edlebrock which is 2.5 turns, because I have figured it was running to rich I took it to 1.5 and 1 it acts the same regardless of where I set the idle mix.

I have already tried what you said with not pumping the gas, just hopped in the truck, put the accelerator to the floor and tried to start same thing. Also done this with choke fully open and fully closed with no hange.

Also I dont think its a distributor issue at all. I pluged my timing light and it fires of every time. I did notice though that the timing mark on the crank is not lined up with the marker... its about 1/4 to 1/2 inch infront of it. See the following picture.

https://photos.app.goo.gl/3YpobCVEoHeqVadt9

LS short box 11-26-2020 09:58 PM

Re: 86 Scottsdale - No start
 
Back in the day my wife's 70 Impala was acting weird. Hard starting. Come to find out the bushings inside the distributor had seized on the shaft. It made the body of the distributor rotate and change the timing. Don't recall if it advanced or retarded the timing. Worth putting in a piston stop and confirming timing marks. Easy to make a piston stop out of a spark plug. Just cut the electrode off and weld a small piece of round stock. Turn the engine over by hand one way and when the piston (#1) comes up against the stop mark the balancer. Then turn it the other way and mark the balancer. Half way between those two marks will be TDC on the balancer.

BAChevyMan 11-27-2020 12:05 PM

Re: 86 Scottsdale - No start
 
Quote:

Originally Posted by LS short box (Post 8841391)
Back in the day my wife's 70 Impala was acting weird. Hard starting. Come to find out the bushings inside the distributor had seized on the shaft. It made the body of the distributor rotate and change the timing. Don't recall if it advanced or retarded the timing. Worth putting in a piston stop and confirming timing marks. Easy to make a piston stop out of a spark plug. Just cut the electrode off and weld a small piece of round stock. Turn the engine over by hand one way and when the piston (#1) comes up against the stop mark the balancer. Then turn it the other way and mark the balancer. Half way between those two marks will be TDC on the balancer.

Please refer to the following picture in reference to engine timing.
https://photos.app.goo.gl/3YpobCVEoHeqVadt9

geezer#99 11-27-2020 12:48 PM

Re: 86 Scottsdale - No start
 
That pic shows your balancer mark might be out of wack from where it should be.
The balancer could have slipped or the timing tab is in the wrong place.
The timing tab was at 12 or 2 o’clock position depending on motor or year. Timing cover could have been changed.
You need to confirm the balancer/tab are accurate.
A piston stop that screws into #1 plug hole works best.

cadillac_al 11-27-2020 08:40 PM

Re: 86 Scottsdale - No start
 
If you really want to start at square one, you should do a compression check. Then check your timing tab/balancer marks. It does kinda sound like the timing chain jumped a tooth but personally I don't believe chevys jump time as easy as other engines. I had a 305 that the timing chain got so loose it wore a hole clean through the timing cover. With good compression and an accurate timing mark it should fire right up.

I was a little confused about a previous post about holding it to the floor to start it. That should not be necessary unless it is really flooded. It is harder on the starter to crank it with the throttle open.


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