The Truck in need of help
'84 F-150 4x4, 302 (2 barrell)

Today we got an Edelbrock Performer Intake, Holley 600 CFM carb.

Got everything installed. We eliminated the EGR.

Fired the truck up, idle is too slow. IT spurts flames out of the carbeurator. What do we do?!?! We tried a few things and nothing seemed to work. What are we over looking? It is 2 am now and I'm tired

If you have any ideas please respond. Thanks.

 

Your timing is too far advanced, or you hooked up the vac advance on the dist. wrong. The mixture needs to be set as well.

 

Also we had to remove the Distributor to take out the old manifold, we marked it all up and it went in exactly the same way it came out. Could it gotten out of time?

I have never had any problems like this when installing a new carb.

So I am asking for you veteran carbeurator owners out there for help!!!!!!!

 

Where should the vaccum advance on the distributor be hooked for sure? MY friend un did that while I was on a parts run, and he claims it is how it was.

Which way would you rotate the distributor to un-advance the timing?

I know the basics of engines and working on them, always have had help when getting into great detail and I need all the help I can get.

The book that came with the carb said that we should NOT have to adjust the mixture it should be good from the factory. It says to make it more lean to turn each screw in (on each side of carb till max vaccum is achieved) I did this and the vaccum did not go up or down.

Another thing there is little or no vaccum when idling on its own.

 

Okay, first, you should have at least 17" of vacuum at idle. What do you have, and where are you getting it from?

The little nipple on the passenger side of the front metering block on the carb is where the vacuum advance hose from the distributor goes.

To adjust your mixture:
1) Gently turn both mixture screws in until they bottom out.
2) Back them both out 1 1/2 turns.
3) Warm up engine
4) Turn idle speed down as LOW as the engine will maintain.
5) Adjust the screws in two round trips (adjust one side, then the other, then come back to the first side, then go back to the other side) to get the highest RPM, or vacuum gauge reading.
6) Add an aditional 1/8 turn out for each screw.
7) Reset idle speed to desired level.
8) Shut off engine and check that both screws are the same. If they're not, set both to the average of the two.
9) Restart engine to check idle quality.

Check your timing with a vacuum gauge too. Turning the distributor clockwise advances it, while turning it counterclockwise retards it. Adjust it to achieve the highest reading on a vacuum gauge, then retard it so the gauge needle drops half a number.

Take care,
-Chris

Take care,
-Chris

 

The most vaccum we got was out of one of the back ports on the "tree" on the intake where the power brakes hook in. We got around 10.

I know the vaccum advance is hooked up wrong and we need to fix that.

 

Then you have a serious problem that needs to be taken care of right away. If the ignition or cam timing is severly retarded, the manifold vacuum will drop, and if the idle mixture is too lean, it will drop. What has probably happened is that either the distributor is off by a tooth, or the marks were wrong, and now the timing is too far retarded. That will effect the idle, and make the vacuum gauge less responsive to the mixture screws.

Do this:

Verify the ignition timing. Compare the TDC mark on the balancer and the rotor in the distributor, and make sure the rotor is at cyl 1 when the TDC mark hits the pointer (on the compression stroke). Start the engine, and then adjust the mixture like I described above. Then, check the timing with a vac gauge, like I said above, and then fine tune the mixture screws again. Trust me here, and don't leave out any steps. Also, make sure all vacuum ports on the carb base plate are capped or are used. Disconnect the vac. advance hose when setting the timing.

Take care,
-Chris

 

Ok I just went and worked on the truck for a few minutes. I hooked up the vacuum advance the way you described and I turned the mixture screws out 1.5 turns. I fired the truck up and she idled perfect at 1,000 rpms.

When I gave it gas it started to pop and a flame shot out of the carbeurator again.

Where would you reccomend hooking up the vaccum meter?

I'm new to timing so this could be a challenge for me. Right now I lost both of my helpers.

If you have a phone number could I get it from you? You can drop it in my email if you would. Then when we start to work on it we can call someone who knows what is going on.

Thanks again, any more help would greatly be appreciated.

 

Also I do not have a book for this engine (since its my friends) and I do not re-call for sure which cylinder is #1 since its been a while since I have had a 302.

Thanks again.

 

FRONT

5 1
6 2
7 3
8 4

 

The vacuum gauge is fine where you had it.

I suspect you have a blown power valve in the carb. You're description is pretty textbook. All it takes is one backfire through the carb to blow them out.

Timing is simple, what do you want to know?

 

By far the best instructions I have found yet for adjusting A/F. I did it this way and not only got a higher vacuum at idle, but I ended up having the idle screw turned down a full turn from what I had! It sure feels a lot better now! Thanks!

I still want to re-check my timing once more, but I will definitely use the vacuum gauge with the timing light to see what happens.

 

Thanks for the kind words, I'm glad things worked out for you. If you're interested, I put a collection of some of the help posts I've done for people over the years into a Tech Tips forum on my website. Check it out, you might find some help you didn't even know you needed.

http://www.ricehatersclub.com/vbulle...splay.php?f=30

 

I will be bookmarking that for sure. Thanks again!