Rich Carb

-

Burntorange70

Well-Known Member
Joined
Feb 18, 2008
Messages
12,873
Reaction score
146
Location
Aguanga, CA.
I have a 650 Eddy carb on my other wise stock 340. I think it is running on the rich side. When I start it in the morning it does fine. Then after it worms up fully it boggs off of idle. I have put in pic's of the plugs. What do you think? I have a jet kit coming. It should be here on friday.

My Question is, what do I do? I have never opened up a carb befor.
I know I need to lean it out but do not know how. can one of you walk me through it?

Thank you for any help, Russell.

100_0324.jpg


100_0325.jpg
 
May be a little rich, but not all that bad in my opinon. Edelbrocks are generally lean out of the box. However, you really can't 'read' your plugs like that. To really do it that method you would have to do a few things. To get cruising mixture you'd need to install a brand new plug, crank it up and immediately get up to speed for a minute or so, shut it down while rolling, and check it. Idling will throw a 'reading' decently out of whack. Same goes for tuning wide open throttle...
 
Are you sure it's not really running lean, and bogs after the choke comes off? Try disabling the choke and see what happens. Do you get gobs of black smoke when it's warm and bogs?
 
I live in southern California so I don't run the choke. I went out just now and fiered it up. It has been sitting about an hour and a half sence I got home.
It comes off of idle just fine, With the choke on or off. But I know if I go and drive it on the HWY a few miles and then try it again it will bogg or stumble off of idle.
 
I wish I could help you with the eddie but I'm a holley guy. Does it stumble/bog only under load or even if it just sits in neutral/park?
 
I might not know what I'm talking about but that plug looks awful clean to be running rich.
 
couple things to check...see if the acelerator pump is working correctly...as soon as the throttle moves the pump should shoot gas..

you might need to adjust the size of the squirter also..

is it a 650 thunder series? you might want to check the tension on the air valve in the secondaries...

also check your timing ....
 
Do you get gobs of black smoke when it's warm and bogs?


No, It never smokes.[/QUOTE]

If you get no black smoke on stumble/bog you're not running rich. Your plug shows lean if anything. Is your accelerator pump working properly?
 
couple things to check...see if the acelerator pump is working correctly...as soon as the throttle moves the pump should shoot gas..

you might need to adjust the size of the squirter also..

is it a 650 thunder series? you might want to check the tension on the air valve in the secondaries...

also check your timing ....

It is a 650 thunder series carb.

the acelerator pump does shoot gas as soon as the throttle opens.
I have tryed the pump in all three holes with no change, that I can tell.

I have not tuched the air doors at all.
 
I wish I could help you with the eddie but I'm a holley guy. Does it stumble/bog only under load or even if it just sits in neutral/park?


All three.

I have a 4-speed. If I rev it up,to 2000 to 2500 rpm then go it does better,but then I just smoke the tires.
 
34 to 36 total is good. You really don't want more than that. How many miles on this engine? Is it 100% stock, never been rebuilt?
 
forget initial 8 degrees btdc is way off .forget initial altogether .try setting total at 35 with full advance coming in by 2000 to 2500 rpm.if ya dont need the vaccum just leave the carb vac. line plugged,if you do need vac advance set total as mentioned above, dont just set it at this number check with a person watching the tach and with an adjustable timing light set at 35 degrees and give it some fuel, rev it past 4000 rpm and watch if it passes 35 degrees,use the dial to bring it to tdc and record the rpm and advance required to hit tdc at 35 degrees that will tell you when full advance is coming in.over 2500 rpm scrap the distributor unless its an msd.jegs sells the M.P. kit with built in fast advance curve normally all in by 2000 to 2500.the orange box or chrome will suffice depending on your engine rpm range.now that this is done properly reattach the vacuum line and recheck the timing. you should now have 53 degrees total, if not insert a small hexkey into the vaccum pot and every half turn will advance the spark timing or retard it, play around with it til you have 53 degrees with full advance in by 2000 to 2500 ,your plugs look lean to me and your timings way offbase.hope this helps
 
It was rebuilt one time that I know of in the late 80's. It has been in the family sense 1991. I have only changed out the gaskets and put a slightly bigger cam and lifters in it. I don't know how big the cam is but remember being toled it was just a little bigger than stock. It has 96000 miles total on it but a big chunk of that was put on befor I got it.

Other than the cam and carb it is stock.
 
after youve done this then check your plugs, the ceramic should have a even slight tan color
 
if not, rejet,with the timing light on the damper if you see fluctuations your chains stretched. sorry for the multiple posts.want a lion? do as above stated.
 
mopar3762, Thank you. I did what you said. It gets up and moves now. The mecanical advance was coming in at 3000 RPM. I have a dist recurving kit comeing too. What should I set it up at 2000 or 2500?
 
You added 1 degree of advance total (and the only way to do that without recurving your distibutor is to add 1 degree initial) and your probelm is solved? I'm confused.

Please enlighten me.
 
When you changed the cam, did you replace the cam chain?

Yes I did.

I got an Eddy air gap, TTI's and a Comp 274 extreme energy cam I am going to put on. I got the complete kit with lifters timing chain and valve springs.

It should be fun:cheers:
 
Well I went out found when the advance was going all in. It was 3000 so I had my girl frind hold revs at 3000 and set the total timing. Then I brought it back down to idle. Now the inital was 15 BTDC. Usually I set the inital at 8 BTDC then rev it up and it would read 34 at 3000.

So to answer your question ramcharger.
I don't know?
 
-
Back
Top