Let's try again - Off-Road Forums & Discussion Groups
IH Scout & Trucks Discussion of International Harvester, 4-Wheel Drive Truck and Scout Vehicles

LinkBack Thread Tools Display Modes
post #1 of (permalink) Old 08-22-2003, 01:15 PM
Posts: n/a
Let\'s try again

I've got a mechanical problem with my 80 scout II! It's been hesitating severely off the line or under load. It's a 345 v8, manual tranny with an edlebrock carb and an electric in line fuel filter.
I've heard everything from vapor lock(i live in tahoe and elevation can aggrivate vapor lock) to worn bushings in the distributor to carboration or ignition.
Does anybody out there have any ideas or have gone through this before. Any help would be appreciated.
Thanks for your time
Sponsored Links
post #2 of (permalink) Old 08-22-2003, 04:40 PM
Join Date: Jan 2003
Location: Fond du Lac, WI
Posts: 113
Thanks: 0
Thanked 1 Time in 1 Post
Re: Let\'s try again

Have you done anything to the carb since you bought it? The diff in elevation could cause an big rich condition and cause problems. Sorry but this all I can think of. It may help.....it may not....good luck
garscout is offline  
post #3 of (permalink) Old 08-22-2003, 10:17 PM
Join Date: Jun 2002
Posts: 264
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Let\'s try again

I agree with garscout about maybe needing to lean it out a bit, also maybe a vacuum leak?
mobyguzzer is offline  
Sponsored Links
post #4 of (permalink) Old 08-23-2003, 06:43 PM
Posts: n/a
Re: Let\'s try again

From what you say I wouldn't think rich, rich will keep running but feel "Boggy" like it didn't do much to give it more thorottle but it didn't cut out. You don't mention if it does this cold or ever has backfiring through the carb<indicates lean or burnt intake valve>

Let me give you a rundown on rich lean detection...
Your sparkplugs are readable and they will tell you lots and lots of things, given you are using the proper heat range to begin with.
If you suspect you are overly rich or lean you should remove your plugs and take a look at the insulator color. If it is black and sooty you have too large jets in the carb, too high a fuel level in the carb, choke sticking, or severly clogged air cleaner.. all of these will cause more fuel to flow from the carb..
On the other hand if they are near white<indicating lean> or very light tan color you may have trash in the jets and not getting the prescribed ammount of fuel per volume of air the engine is pulling. Could also have a fuel restriction in the filter or line also... I guess you know about the drain hole on the bottom of the fuel tank, mine used to get clogged with rust when I first started driving my scout again.

The appropriate color of plug insulators are tannish in color not approaching black nor white. Red indicates a probable octane booster and makes plugs impossible to read until you get some new ones unless you are sooty rich. Remember these are the only things inside your combustion area you can remove and look at.
They can tell you lots of things. If you have some right and some more light they can tell of more serious things like with split manifolds that feed off different carb barrels one jet may be clogged and another free giving a light color on the ones feeding from the clogged barrel...
On the other hand if the two middle ones are white and the two outers darker and you are loosing a little coolant you may have a head gasket leaking and the coolant washing the plugs white.
Last but not least if you have a non clear filter, cut it open and see what it looks like inside, rust can also get past the filter if very fine and get under the rubber on the needle seat and prevent it from closing allowing the fuel level in the bowl to raise and therefore run rich, some electric fuel pumps have too high pressure to begin with and will push the needle off seat anyways, a simple pressure regulator set to about 3 1/2 pounds will correct this if you find nothing else wrong.
Another thing is if the venturi size is too large for the ammount of air your engine is flowing, there will be no velocity of the air through the center which by the way is how a carb regulates how much fuel to give...but being a 345 I don't think that would be the problem. Have you had this prob ever since you got this carb?
I need somemore info but I'll help ya get it straight [img]images/graemlins/blush.gif[/img])
Just noticed it was a scout II, may not have the drain on the tank bottom, check the filter...
Look here also
post #5 of (permalink) Old 08-24-2003, 07:16 PM
Posts: n/a
Re: Let\'s try again

Thanks a lot. I really appreciate the info.
I forgot to say that one of the biggest symptoms was that it ran solid first thing in the morning until it warms up. That's when the problem occurs. Some one was saying it could be the egr valve because of this but I'm pretty sure I'm pretty sure I have it plugged. What do you think?
As for backfiring in the carb. I'm not really sure how to tell. When i'm off the throttle going down hill you can hear backfiring from the front of the car.(exhaust?)
I'll check the plugs, and the rest as soon as possible. Once again thanks for all the help!!
drewd [img]images/graemlins/40BEER.gif[/img]
Sponsored Links

Quick Reply

Register Now

In order to be able to post messages on the Off-Road Forums & Discussion Groups forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may not post new threads
You may not 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

For the best viewing experience please update your browser to Google Chrome