1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks Discuss the Early Eighties Bullnose Ford Truck

351w Idle problems

Thread Tools
 
Search this Thread
 
  #46  
Old 04-23-2018, 06:27 PM
Brnfree's Avatar
Brnfree
Brnfree is offline
Laughing Gas
Join Date: Apr 2013
Posts: 972
Received 43 Likes on 36 Posts
Glad you found your vacuum leak.

What’s wrong with EGR? Personally I see a lot of benefits; engine cooling, better mileage, and the ability to carry more vacuum advance.

And speaking of vacuum advance I run manifold with EGR. Crusing down the highway under light throttle the EGR is open and the vacuum advance is all in. Crazy as it sounds, at idle I’m 10* base spark advance + another 15* vacuum advance with the idle speed and mixture set accordingly. Throttle response is crisp off the line and the vacuum advance fades right out under throttle so there’s no pinging.

If if you want to start modifying the emissions I suggest you try manifold vacuum advance before eliminating the EGR.
 
  #47  
Old 04-23-2018, 06:30 PM
Jghake's Avatar
Jghake
Jghake is offline
Mountain Pass
Thread Starter
Join Date: Mar 2018
Location: Puyallup, WA
Posts: 233
Likes: 0
Received 1 Like on 1 Post
This thing has already been tore into by someone else. All the emissions is disabled currently. I am now faced with keep it disabled, or add it back in...

Originally Posted by Brnfree
I suggest you try manifold vacuum advance before eliminating the EGR.
I already have a vacuum line going from the front of the carb to the vacuum advance. Is that what you're talking about?
 
  #48  
Old 04-23-2018, 08:23 PM
Brnfree's Avatar
Brnfree
Brnfree is offline
Laughing Gas
Join Date: Apr 2013
Posts: 972
Received 43 Likes on 36 Posts
Originally Posted by Jghake
This thing has already been tore into by someone else. All the emissions is disabled currently. I am now faced with keep it disabled, or add it back in...



I already have a vacuum line going from the front of the carb to the vacuum advance. Is that what you're talking about?
I’m referring to where your distributor gets its vacuum from. “Ported versus Manifold” vacuum. They are two different things and you may prefer one over the other. Unlike “Ported” “Manifold” vacuum is full suction at idle.

There are many layers to the onion.
 
  #49  
Old 04-23-2018, 08:26 PM
ctubutis's Avatar
ctubutis
ctubutis is offline
Moderator
Join Date: Nov 2007
Location: Denver Metro Area, CO
Posts: 22,405
Received 72 Likes on 56 Posts
EXACTLY WHERE on the front of a carburetor makes a big difference here.
 
  #50  
Old 04-23-2018, 09:32 PM
Jghake's Avatar
Jghake
Jghake is offline
Mountain Pass
Thread Starter
Join Date: Mar 2018
Location: Puyallup, WA
Posts: 233
Likes: 0
Received 1 Like on 1 Post
It's on the bottom near the mixture screw on the right, just under the front of the float bowl.
 
  #51  
Old 04-23-2018, 09:45 PM
ctubutis's Avatar
ctubutis
ctubutis is offline
Moderator
Join Date: Nov 2007
Location: Denver Metro Area, CO
Posts: 22,405
Received 72 Likes on 56 Posts
Sounds like should be manifold vacuum there.
 
  #52  
Old 04-26-2018, 08:58 AM
matthewq4b's Avatar
matthewq4b
matthewq4b is offline
Post Fiend
Join Date: Feb 2008
Location: St Albert, Alberta
Posts: 5,831
Received 114 Likes on 97 Posts
Originally Posted by ctubutis
Sounds like should be manifold vacuum there.

Sounds right to me also the should be manifold vacuum.
Ported for the Dist should be on the passenger side of the carb base plate just in front of the choke assy.
 
  #53  
Old 04-26-2018, 08:06 PM
Franklin2's Avatar
Franklin2
Franklin2 is offline
Moderator
Join Date: Jan 2001
Location: Virginia
Posts: 53,625
Likes: 0
Received 1,678 Likes on 1,356 Posts
Unless you want to do a bunch of re-tuning on the engine, I would leave the distributor on ported vacuum which would be no vacuum at idle on the distributor.
 
  #54  
Old 04-27-2018, 10:28 AM
Jghake's Avatar
Jghake
Jghake is offline
Mountain Pass
Thread Starter
Join Date: Mar 2018
Location: Puyallup, WA
Posts: 233
Likes: 0
Received 1 Like on 1 Post
Originally Posted by Franklin2
Unless you want to do a bunch of re-tuning on the engine, I would leave the distributor on ported vacuum which would be no vacuum at idle on the distributor.
Well I haven't changed where this dist was connected to the carb. I'll check vacuum on this line at idle again. If I remember correctly it wouldn't go below 3-5.
 
  #55  
Old 04-30-2018, 03:28 PM
Jghake's Avatar
Jghake
Jghake is offline
Mountain Pass
Thread Starter
Join Date: Mar 2018
Location: Puyallup, WA
Posts: 233
Likes: 0
Received 1 Like on 1 Post
Its running like crap again today, I think because its cold. I'm going to replace the carb gaskets and retune. How do I find my total advance? I can't really read the timing marks very well. I've marked 10 for the idle timing, but I was hoping to check the advance timing too.
 
  #56  
Old 04-30-2018, 05:40 PM
Tedster9's Avatar
Tedster9
Tedster9 is offline
Post Fiend
Join Date: Apr 2002
Location: Waterloo, Iowa
Posts: 19,311
Likes: 0
Received 66 Likes on 65 Posts
Originally Posted by Jghake
Its running like crap again today, I think because its cold. I'm going to replace the carb gaskets and retune. How do I find my total advance? I can't really read the timing marks very well. I've marked 10 for the idle timing, but I was hoping to check the advance timing too.
Go here:

http://gofastforless.com/ignition/advance.htm

It explains the routine really well. Run it up in neutral with a timing light and see where it tops out at.
 
  #57  
Old 05-14-2018, 10:57 AM
Jghake's Avatar
Jghake
Jghake is offline
Mountain Pass
Thread Starter
Join Date: Mar 2018
Location: Puyallup, WA
Posts: 233
Likes: 0
Received 1 Like on 1 Post
So I have been fighting this since I bought it. I've been able to use it a few days and it will run just fine, then the next it runs like a pig again.

I pulled the carb off this weekend and did a visual inspection of the inside. The previous owner told me it had been rebuilt, and it looks like it has been recent.

The truck runs great above 1500 RPM. It pulls up hills well, shifts well, and drives well. It is only when I come to a stop that I start having issues.

Now my question to everyone is, I was gifted an Edelbrock 1406 with an electric choke. It has been sitting for a while and will 100% need rebuild as the butterfly valves are stuck and won't move at all. I found a cast iron 4 bbl intake off an 87 F150 with a 351w on Craigslist for $20. It isn't very convenient to meet up with the guy but it appears I could convert to a 4bbl for relatively cheap.

Does anyone have any input? Should I keep bashing at this truck with the Motocraft 2150 or should I start the conversion to the 4bbl?
 
  #58  
Old 05-14-2018, 12:45 PM
Franklin2's Avatar
Franklin2
Franklin2 is offline
Moderator
Join Date: Jan 2001
Location: Virginia
Posts: 53,625
Likes: 0
Received 1,678 Likes on 1,356 Posts
The 4bbl conversion is worth the time and effort to do. You definitely get more power from it, and the aftermarket carbs have more adjustment to them for different situations, and adapt better when emssions stuff is messed with. Who knows if it will cure any of your problems, but I would try it myself, with a rebuild of course.
 
  #59  
Old 05-14-2018, 12:55 PM
Jghake's Avatar
Jghake
Jghake is offline
Mountain Pass
Thread Starter
Join Date: Mar 2018
Location: Puyallup, WA
Posts: 233
Likes: 0
Received 1 Like on 1 Post
Should I look to see if my EEC is throwing any codes? I can't find the proper procedure to look for codes?

I am so sick of this truck not working... It needs to start pulling its weight soon...

Here is the intake for sale on Craigslist. I was told it was out of a running 87 F150 with a 351w. Should this work on my 83 351w?
 
Attached Images  
  #60  
Old 05-14-2018, 04:41 PM
FuzzFace2's Avatar
FuzzFace2
FuzzFace2 is offline
Fleet Owner
Join Date: Nov 2015
Location: Angier, NC
Posts: 23,682
Received 2,103 Likes on 1,791 Posts
First I would give the carb a rebuild to see if it will take or not.
If it will not take, free up, you are only out the rebuild kit $ before going for a intake.

Now this intake there is no way I would install a heavy stock 4v intake mostly because it is HEAVY!
You should be able to find a alum. after market one cheap.
I would look for Edelbrock performer intake. It is lighter so you will not hurt yourself lifting it over the fender and it should give a little boost over the stock one too.

If you don't want to swap intakes look for a Holley 2300 v2 in the 500 cfm size it will bolt right on to your intake and the stock air filter should fit too.
I did this swap, Holley 2300 v2 500 cfm for the stock Motorcraft 2150 on a 304 AMC v8 and was the best thing I ever did to that motor.
Unless you looked real close you could not tell with the stock air filter in place.
Dave ----
 


Quick Reply: 351w Idle problems



All times are GMT -5. The time now is 03:32 AM.