Premium gas issues? - JeepForum.com
Reply
 
LinkBack Thread Tools
post #1 of 31 Old 02-07-2014, 06:06 PM Thread Starter
RCYJ
Registered User
1987 YJ Wrangler 
 
Join Date: Nov 2007
Location: NYC
Posts: 61
Premium gas issues?

Hello all,

I have an 87 yj 6 cyl with a Weber carb. I live in NY so it's cold. Haven't use the jeep for about 4 months because of brake issues but now it's fixed. During brake testing I used up the gas so I went to gas up and decided to use premium Sunoco 93. During the drive home engine won't idle? Did the 93 gas affect the carb. Had no issues before while testing brakes around the block a few times. Should I siphon the gas? Thanks for any help.

RC

RCYJ is offline  
Sponsored Links
Advertisement
 
post #2 of 31 Old 02-07-2014, 07:06 PM
Mark05059
Registered User
1989 YJ Wrangler 
 
Join Date: Mar 2009
Location: quechee Vermont
Posts: 4,696
probably the carb is gummed up from sitting... the 93 octane shouldn't have any adverse conditions...

1998 ZJ 5.2 Auto

1989 Wrangler Black Bone Stock 2.5l 5spd
/l , [____],
|---L--[]lllllll[]-
()_) ()_)==O=)_)
Mark05059 is offline  
post #3 of 31 Old 02-07-2014, 08:22 PM
Michaelgoesrawr
Web Wheeler
 
Michaelgoesrawr's Avatar
1988 YJ Wrangler 
 
Join Date: Nov 2009
Location: Pinion Hills
Posts: 8,309
Garage
Don't waste your money on high octane stuff. Change your fuel filter and check to make sure your carb isn't gummed like said above.

Adopt your pets. Don't shop for them.
Michaelgoesrawr is online now  
post #4 of 31 Old 02-07-2014, 09:19 PM
plym49
Registered User
1990 YJ Wrangler 
 
Join Date: Jan 2009
Location: NA
Posts: 1,584
Nothing will gum up in 4 months. You do not need premium gas. Premium gas burns SLOWER than regular. It has to, to prevent detonation in a high-compression engine.

Your Jeep six is not high compression! If anything, the premium is working against you in the bitter cold you describe.

Use the lowest octane gas available - 87 - in your Jeep. All premium does in your case is to separate you from your money.
plym49 is offline  
post #5 of 31 Old 02-07-2014, 09:45 PM Thread Starter
RCYJ
Registered User
1987 YJ Wrangler 
 
Join Date: Nov 2007
Location: NYC
Posts: 61
Yeah, I thought maybe it will help start the jeep better since it was sitting for a while. I'll change that filter and maybe siphon it out. How can you tell if the carb is gummed out?
RCYJ is offline  
post #6 of 31 Old 02-07-2014, 09:58 PM
imstillatwork
Registered User
1993 YJ Wrangler 
 
Join Date: Aug 2009
Location: Oregon Coast
Posts: 1,600
Myth: premium has more power / burns hotter
NO!!!

'premium' is higher octane... the higher octane, the more pressure / heat the fuel can withstand before it ignites spontaneously... takes longer to burn, is more difficult to ignite!
High performance, high compressions engines need higher octane fuel so that the fuel ignite ONLY when it is 'told' to by the spark plugs. Low compression, low performance engines absolutely do not need, and cannot take advantage of high octane fuels. It might even run WORSE if the ignition system is not up to snuff.

A high compressions motor can pre-ignite the fuel if it is not high enough octane. You get 'ping' or 'knock' due to this. The fuel is igniting while the piston it still headed UP, because the fuel ignited too early due to high pressure /heat in the combustion chamber.

A high compression motor can make more power because the benefits of high compression overcome the negatives of hi octane.
imstillatwork is offline  
post #7 of 31 Old 02-08-2014, 09:16 AM
90DesertTanYJ
Registered User
1990 YJ Wrangler 
 
Join Date: Jun 2012
Location: Jacksonville
Posts: 749
If you have Chevron gas in your area you could try some of it to help with your fueling issues. If not available, look for Techroline additive at an auto parts.
90DesertTanYJ is offline  
post #8 of 31 Old 02-09-2014, 06:32 PM
plym49
Registered User
1990 YJ Wrangler 
 
Join Date: Jan 2009
Location: NA
Posts: 1,584
Quote:
Originally Posted by RCYJ View Post
Yeah, I thought maybe it will help start the jeep better since it was sitting for a while. I'll change that filter and maybe siphon it out. How can you tell if the carb is gummed out?
If the engine runs but has a problem idling, your fuel filter is fine. Why? Because you require higher fuel flow running above idle. A plugged filter decreases flow - the engine idles but won't make power - exactly the opposite of what you are reporting.

The same thing goes for a gummed up carb. Idle is less affected, because less fuel is required. I doubt your carb is gummed. I also doubt your fuel filter is bad since the Jeep was running fine before storage. If the motor was not running during storage, how could the fuel filter get dirty?

These two general guidelines in the world of troubleshooting.

If you have told us all of the story, top it off with regular and drive it and it will be fine.

If there is more to the story, for example the motor would not idle when it was cold, or fully warmed up, then by all means fill in the details.
plym49 is offline  
post #9 of 31 Old 02-09-2014, 08:17 PM Thread Starter
RCYJ
Registered User
1987 YJ Wrangler 
 
Join Date: Nov 2007
Location: NYC
Posts: 61
Quote:
Originally Posted by plym49 View Post
If the engine runs but has a problem idling, your fuel filter is fine. Why? Because you require higher fuel flow running above idle. A plugged filter decreases flow - the engine idles but won't make power - exactly the opposite of what you are reporting.

The same thing goes for a gummed up carb. Idle is less affected, because less fuel is required. I doubt your carb is gummed. I also doubt your fuel filter is bad since the Jeep was running fine before storage. If the motor was not running during storage, how could the fuel filter get dirty?

These two general guidelines in the world of troubleshooting.

If you have told us all of the story, top it off with regular and drive it and it will be fine.

If there is more to the story, for example the motor would not idle when it was cold, or fully warmed up, then by all means fill in the details.
Jeep was running and idling fine before putting the premium. The only issued were the brakes. I will siphon the gas and see what happens. Thanks.
RCYJ is offline  
post #10 of 31 Old 03-09-2014, 07:29 PM Thread Starter
RCYJ
Registered User
1987 YJ Wrangler 
 
Join Date: Nov 2007
Location: NYC
Posts: 61
So it's not the gas. The carb (weber) is not idling. Looks like the choke is not working causing the butterfly flaps to open up too much. Do anyone know how to adjust this?
RCYJ is offline  
post #11 of 31 Old 03-09-2014, 07:54 PM
Mark05059
Registered User
1989 YJ Wrangler 
 
Join Date: Mar 2009
Location: quechee Vermont
Posts: 4,696
the choke cap usually has 3 rivits holding the cap on. Drill those out and get some bolts/nuts to replace them with. You adjust the choke by turning the cap. If its opening too fast then the electrical part of it is working... but working too well..

1998 ZJ 5.2 Auto

1989 Wrangler Black Bone Stock 2.5l 5spd
/l , [____],
|---L--[]lllllll[]-
()_) ()_)==O=)_)
Mark05059 is offline  
post #12 of 31 Old 03-10-2014, 04:51 PM Thread Starter
RCYJ
Registered User
1987 YJ Wrangler 
 
Join Date: Nov 2007
Location: NYC
Posts: 61
Quote:
Originally Posted by Mark05059 View Post
the choke cap usually has 3 rivits holding the cap on. Drill those out and get some bolts/nuts to replace them with. You adjust the choke by turning the cap. If its opening too fast then the electrical part of it is working... but working too well..
Choke cap actually already had screws so I adjusted by turning to the left to close it more, but it didn't really help. The butterfly flaps still stays fully vertical,when engine is hot and letting go of the throttle which what causes the engine to stop. Maybe the electric choke has no power. I have to test it.
RCYJ is offline  
post #13 of 31 Old 03-10-2014, 05:53 PM
roadyrob
Registered User
1987 YJ Wrangler 
 
Join Date: Apr 2007
Location: west palm beach fl
Posts: 1,978
the choke is supposed to be off when the motor is hot. heres a thread on the weber carb, maybe it will help you.
http://www.jeepforum.com/forum/f8/we...ssion-1051137/

Do everything with a positive attitude, it won't always work but you'll piss enough people off to make it worthwhile.

the voices aren't real but they sure have good ideas.
roadyrob is offline  
post #14 of 31 Old 03-10-2014, 05:58 PM
jollyroger1
Registered User
1990 YJ Wrangler 
 
Join Date: Oct 2011
Location: Nashville
Posts: 36
I had the same issue a couple months ago,it was a vacuum leak.The adapter plates under the webber had loosened up
jollyroger1 is offline  
post #15 of 31 Old 03-10-2014, 06:38 PM
captainauti
Registered User
1995 YJ Wrangler 
 
Join Date: Oct 2008
Location: One Particular Harbor/ Ocean State
Posts: 1,129
Quote:
Originally Posted by plym49 View Post
If the engine runs but has a problem idling, your fuel filter is fine. Why? Because you require higher fuel flow running above idle. A plugged filter decreases flow - the engine idles but won't make power - exactly the opposite of what you are reporting.

The same thing goes for a gummed up carb. Idle is less affected, because less fuel is required. I doubt your carb is gummed. I also doubt your fuel filter is bad since the Jeep was running fine before storage. If the motor was not running during storage, how could the fuel filter get dirty?

These two general guidelines in the world of troubleshooting.

If you have told us all of the story, top it off with regular and drive it and it will be fine.

If there is more to the story, for example the motor would not idle when it was cold, or fully warmed up, then by all means fill in the details.
just a thought..... if the idle circuit is clogged, wouldnt that cause idle issues, reguardless of fuel demand?

OP, 4 month old fuel could be bad. if the ethanol fuel you had in your tank has separated, and/or sludged up, you could have clogged up the carb. get a rebuild kit and go to it. and when ever you lay anything up with fuel in it, use startron.

_______________________
Capt. Nate
aka Scallywag
_______________________
95 yj 4.3 vortec csfi, 4l60e/np231cj (scallywag)
1973 Wagoneer (honey wagon)
2013 Escape titanium 4wd ecoboost
2011 F150 4x4 5.0 Coyote SVT Supercrew
2008 E450 v10 Jayco Greyhawk 28 (tildah)

_______________________

captainauti is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

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

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

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
Show Printable Version Show Printable Version
Email this Page Email this Page



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 Off
Pingbacks are On
Refbacks are On

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