Chevy 350, Has spark and gas, wont run - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 11-16-2010, 08:58 PM
CoupeDTS's Avatar
Registered User
 
Join Date: Nov 2010
Location: Nebraska
Posts: 8
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Chevy 350, Has spark and gas, wont run


First some background. Working on a friends Chevy 350. I helped build the motor so I know everything thats been done with it. We built and put it in back in april. Every single part is new, accessories, tranny, bolts, everything! Of course the block is reconditioned but you know what Im saying. Its a 355, mild cam, summit heads, lots and lots of chrome, 600cfm edelbrock, ebay distributor with a MSD coil etc etc.

So the car has been running great since april. A couple weeks ago he said it was starting to miss or run like s**t. Then a day later it quit running and wont start. Has spark and gas.

He doesnt run it hard at all. Hes only got on it hard a few times. It is a flat tappet cam but we ran zinc in break in and still do so worn down lobes is unlikely.

Even with starting fluid it only putts a couple times. Testing the #1 plug wire it makes a long spark and sparks everytime it should.

I threw in a different module and the part thats connected to it with the wires that go out and plug into the cap but that did nothing.

So I took the distributor out to watch the crank and cam both moving. Those looked good.

What else can I check? Im going to check the pickup coil tomorrow, maybe its off or something.

I guess the one thing that wasnt brand new was the carb. I took it apart and it looked clean so we ran with it. And it worked. Could it really be flooding it super bad?

What am I missing?

Thanks

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 11-16-2010, 09:37 PM
68NovaSS's Avatar
Hotrodders.com Moderator
 
Last wiki edit: Working with chromed bolts
Last journal entry: New to me T-Bucket
Last photo:
Join Date: Sep 2002
Location: Nine Mile Falls, Washington
Posts: 5,229
Wiki Edits: 9

Thanks: 103
Thanked 131 Times in 122 Posts
I've seen (and had...) plugs fouled so bad even a hot MSD wouldn't fire them in my blower car. Threw in a new set and fired right off...wouldn't hurt to check them...

Is the carb dumping fuel?
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 11-17-2010, 05:20 AM
CoupeDTS's Avatar
Registered User
 
Join Date: Nov 2010
Location: Nebraska
Posts: 8
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I took out the #1 plug. It was wet of course. It was a little black but I wouldnt say out of the ordinary? I guess I dont know what a fouled plug looks like? And if they were, how do you prevent that from happening?

Also what do you mean is the carb "dumping" fuel? I can move the throttle and see gas shooting out of the jets.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 11-17-2010, 06:12 AM
cobalt327's Avatar
WFO
 
Last wiki edit: Intake manifold
Last journal entry: 1980 Malibu Wagon
Last photo:
Join Date: Mar 2009
Location: Atlanta
Age: 59
Posts: 5,037
Wiki Edits: 1616

Thanks: 128
Thanked 597 Times in 546 Posts
A fresh set of plugs sure wouldn't hurt. I would suggest removing the old plugs, spin the engine over a few times to blow out any excessive fuel, then leave the plugs out for long enough to allow the fuel to evaporate some.

Before starting it, check the timing to see if it has moved. If it has, it could be the timing set (unlikely if new) or the crank gear's woodruff key sheared off in the crank snout.

Also check the distributor gear to see if the roll pin has sheared off. It will likely still look fine, but if it's sheared off, you will be able to turn the gear on the shaft- possibly with a lot of difficulty, because it may still be tight. This doesn't happen often on a SBC, but it can happen, just the same.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 11-17-2010, 06:38 AM
CoupeDTS's Avatar
Registered User
 
Join Date: Nov 2010
Location: Nebraska
Posts: 8
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by cobalt327
A fresh set of plugs sure wouldn't hurt. I would suggest removing the old plugs, spin the engine over a few times to blow out any excessive fuel, then leave the plugs out for long enough to allow the fuel to evaporate some.

Before starting it, check the timing to see if it has moved. If it has, it could be the timing set (unlikely if new) or the crank gear's woodruff key sheared off in the crank snout.

Also check the distributor gear to see if the roll pin has sheared off. It will likely still look fine, but if it's sheared off, you will be able to turn the gear on the shaft- possibly with a lot of difficulty, because it may still be tight. This doesn't happen often on a SBC, but it can happen, just the same.
Good stuff, ill look at all that.

Well probably just go ahead and put in new plugs (theyre cheap), reinstall the distributor and time it and see what happens.

I doubt it was too flooded. He tries to start it a few days apart to see if it will run so I would think gas has time to evaporate out.

I have taken apart those 600 edelbrocks before to clean and install a offroad kit, but if I were to take this one apart is there something I should look for as to why it would be dumping in too much fuel? Float levels or whatever that spring and seal thing is on the front drivers side of it? Since it was the only thing that wasnt new on the engine I wouldnt mind taking it apart and cleaning and maybe rebuilding it.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 11-17-2010, 07:03 AM
cobalt327's Avatar
WFO
 
Last wiki edit: Intake manifold
Last journal entry: 1980 Malibu Wagon
Last photo:
Join Date: Mar 2009
Location: Atlanta
Age: 59
Posts: 5,037
Wiki Edits: 1616

Thanks: 128
Thanked 597 Times in 546 Posts
Be sure the filter is clean and unobstructed and that the fuel pump is set to no more than about 5 psi, and has sufficient volume.

The needle and seat assembly can get debris in it that will cause flooding- you'd see fuel spilling from the boosters if this were the case.

Be sure the floats aren't taking on fuel due to pinholes (if brass) or soaked (if nitrophyl) or cracks (if Duracon, white plastic, hollow).
EDIT- I see this is an Edelbrock carb. So just see that the float isn't heavy. Shaking it will usually tell you- you'll hear it sloshing.

Blow out the passages w/compressed air or carb spray cleaner.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 11-17-2010, 07:11 AM
CoupeDTS's Avatar
Registered User
 
Join Date: Nov 2010
Location: Nebraska
Posts: 8
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Should I get the same spark plugs? We just used the basic ac delco ones for a 350. I dont know anything about plugs besides to gap them right. I dont know what fouling is and Ive heard there are hotter ones or something? Just wondering if I should go with a different part number. Ive heard high performance engines use up plugs faster. My 350s have been a little more mild than my buddies here so I havent had to change mine too often. My dad had a 70 GTO he bought new, he said he had to change the plugs every 10-15k miles. My buddies engine has the bigger valves in the heads, probably 64cc chamber, cam is 284 degree i think. I had a 278 cam, this 284 runs a little choppier. Maybe it burns through plugs quicker.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 11-17-2010, 07:42 AM
RAYFIN's Avatar
Registered User
 

Last journal entry: before picture
Last photo:
Join Date: Oct 2004
Location: Sioux City IOWA
Age: 55
Posts: 108
Wiki Edits: 0

Thanks: 1
Thanked 2 Times in 2 Posts
Squirt a little regular oil into the cylinders. Could be that gas washed down the walls and there is no compression because the rings arent sealing. Then put in new plugs.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 11-17-2010, 08:09 AM
bowtie76's Avatar
Registered User
 
Last photo:
Join Date: Nov 2010
Location: Syracuse, NY
Posts: 28
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I had the same problem. I was running a Holley 650. it was old and rebuilt a few times. But I finally got tired of it and bought a new one. Havent had a problem with it dumping fuel. I had noticed that the fuel/air mixture screws would never stay set and the fast idle screw wouldnt change when you tried to adjsut it. the new carb worked. i woent with a holley 600cfm DP. I also had an issue with plugs in my 350. I had tried to use everything from bosch, autolite, ACdelco and they always fouled out quick. I switched to Accel Shorty header plugs part #8199. They have a U-groove and burn a little hotter. They cost about $30 at the auto store. I havent had an issue since.
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 11-21-2010, 06:41 PM
CoupeDTS's Avatar
Registered User
 
Join Date: Nov 2010
Location: Nebraska
Posts: 8
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
We replaced the plugs. Turns out he had R44T plugs which are for trucks. We went with a R45TS which are for cars and for race cars so we heard. There was a BIG difference in the spark end of the plug. But those old ones were fouled out bad.

After the new plugs it fired right up.

So I learned some about plugs through all this! Always have to learn something..
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 11-21-2010, 11:32 PM
RAYFIN's Avatar
Registered User
 

Last journal entry: before picture
Last photo:
Join Date: Oct 2004
Location: Sioux City IOWA
Age: 55
Posts: 108
Wiki Edits: 0

Thanks: 1
Thanked 2 Times in 2 Posts
A 45 is just a hotter plug than a 44.
Reply With Quote Quick reply to this message
  #12 (permalink)  
Old 11-22-2010, 07:23 AM
CoupeDTS's Avatar
Registered User
 
Join Date: Nov 2010
Location: Nebraska
Posts: 8
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I know the heat thing.

But the difference between a T and a TS at the end of the part number is big. The white part of the plug is buried deeper on the T (truck) plugs where its even with the threads. The TS plug the white part sticks up out of the plug. Supposedly the truck plugs are used for heavy duty trucks that use higher torque in the higher RPM range sbc's.

The car runs alot better now also. We couldnt nail down a good timing on it before but now we timed it to the best spot and it doesnt diesel anymore or anything.

I also leaned out the carb some too just for good measure.

So in this case it WAS the plugs though.
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 11-22-2010, 08:00 AM
cobalt327's Avatar
WFO
 
Last wiki edit: Intake manifold
Last journal entry: 1980 Malibu Wagon
Last photo:
Join Date: Mar 2009
Location: Atlanta
Age: 59
Posts: 5,037
Wiki Edits: 1616

Thanks: 128
Thanked 597 Times in 546 Posts
Quote:
Originally Posted by CoupeDTS
...the difference between a T and a TS at the end of the part number is big. The white part of the plug is buried deeper on the T (truck) plugs where its even with the threads. The TS plug the white part sticks up out of the plug.
The difference between the "T" and the "TS" plug you're describing is the extended tip.

An AC R45TS plug breaks down like this:

R- resistor type
4- 14mm
5- heat range
T- tapered seat
S- extended tip

Last edited by cobalt327; 11-22-2010 at 08:04 AM. Reason: Add link.
Reply With Quote Quick reply to this message
  #14 (permalink)  
Old 11-22-2010, 08:05 AM
CoupeDTS's Avatar
Registered User
 
Join Date: Nov 2010
Location: Nebraska
Posts: 8
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by cobalt327
An AC R45TS plug breaks down like this:

R- resistor type
4- 14mm
5- heat range
T- tapered seat
S- extended tip
thanks, good info and link. I feel like crap Ive always just bought plugs for all my 350s and told my friends for their 350s to just pick an early 80s chevy car or truck with a 350 in it and buy delco plugs.
Reply With Quote Quick reply to this message
  #15 (permalink)  
Old 11-22-2010, 09:01 AM
cobalt327's Avatar
WFO
 
Last wiki edit: Intake manifold
Last journal entry: 1980 Malibu Wagon
Last photo:
Join Date: Mar 2009
Location: Atlanta
Age: 59
Posts: 5,037
Wiki Edits: 1616

Thanks: 128
Thanked 597 Times in 546 Posts
Quote:
Originally Posted by CoupeDTS
thanks, good info and link. I feel like crap Ive always just bought plugs for all my 350s and told my friends for their 350s to just pick an early 80s chevy car or truck with a 350 in it and buy delco plugs.
Well, that's actually not a bad recommendation.

Not knowing what kind of pistons were in another guy's engine, the standard tip plugs wouldn't touch the piston's dome- if it had one. So w/o an extended tip, they'd be a safe bet.

But yeah- if there's no issue w/clearance (which there almost never is these days w/a pump gas fueled engine on the street), the extended tip plugs have a wider 'sweet spot' and are generally an improvement over regular tip plugs.

That said, you'd not want to use extended tips w/nitrous or a lot o' boost, unless you are sure of the set-up.
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Good Sparkplugs for 350 Chevy Imaginos Hotrodding Basics 15 04-09-2012 06:36 AM
4.3L chevy doesnt run right after frozen radiator etc, fast68 Engine 13 03-04-2010 07:22 PM
tbi 350 smells like unburnt gas slammedchevy1500 Engine 23 02-17-2009 07:29 PM
blazer has spark at coil and gas no spark at plugs ricksautorestoration Engine 29 02-15-2007 08:30 AM
overhauled chevy 350 will not crank poundst Engine 4 01-31-2004 11:44 PM


All times are GMT -6. The time now is 07:00 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.