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Adjust carb?

R

RustyRed

Active Member
Still working the bugs out on the new motor, drove it to work this morning to stretch her legs but mostly because my drive to work is about 5 minutes and I am still in the process of tweak, test drive, tweak, test drive, etc.

I think my idle seems a little fast but if I let it idle for a few minutes and shut it off it backfires through the carb....any tips or suggestions on what might be causing that one?
 
I didn't realize how high my idle was until I adjusted it this afternoon.

Yesterday when I got to Aikido instead of a back fire it tried to keep running for a split second when I cut the ignition.

This afternoon I got it out and took the car around the block several times to get it warmed up. Then I turned the idle down some...just played around with it a little and figured out where too low was at and then went to somewhere in the middle. Car sounds a lot better when it is sitting at idle and no back fire or other strange things when I turned it off.

My only guess is that it was getting to much gas in the carb and causing the backfire. Not sure but I'd think that could be dangerous so glad to get it adjusted.

Only issue now is that it takes a bit for it to warm up. If you try to go somewhere it will try to stall out.

I know I've never owned a carb'd 289/302 that wasn't cold natured but is there any adjustments I can make to improve it a little?
 
It's a Holley 570....to be totally honest I don't know what sort of choke it has but the thought had occurred to me that might be the issue.

I'll investigate it some.
 
Probably true Dave....LOL!

Still in the test drive, adjust, test drive, adjust phase and learning as I go. I do think adjusting the idle down some is really going to improve things a lot. Learning as I go basically :)

It's been an adventure so far. I have been reading the shop manual and learning a lot about transmissions the last few days because I am thinking some upgrades there are going to be my next battle.

I am ordering the Trick Flow pan today to resolve my transmission leak once and for all, just tired of dealing with the worn out old stock one. I haven't wanted to drive it "too much" with that leak unresolved so I am still working out the bugs but hope I am getting there.

I am also probably going to replace the dip stick / tube for my transmission. I've no idea how it attaches but guess I'll go back to the shop manual and figure it out. The current tube is dented or bent a little at one point and it makes it a real pain to try and read the fluid level. My only guess is the slightly bent / dented spot rubs the stick when you are pulling it out. Don't know how it got like that but it's been like that since I bought the car and I finally noticed it the other evening when I was under there checking out a few things.
 
no idea how it attaches
Click to expand...

As I remember it's retained into the side of the case by nothing more than an o-ring on the tube. "Pull" upward on the tube and it'll likely come right out.
 
I started thinking about it but I have a wire that plugs into a black round thing on the side of my carb which means it's an electric choke.

Working from memory from yesterday but I believe the plate was straight up and down when it was at running temperature....not sure when the car has been sitting but I'll look when I get home. Luckily I found the "how to" instructions on the Holley website so hopefully I can get it adjusted.

I am starting to remember some of this stuff that I have forgotten...now if I could just figure out the equity section of the consolidated financial statements I am working on. Maybe if I stopped reading up on how to adjust a carb the financials would go faster, LOL!
 
"RustyRed" said:
I started thinking about it but I have a wire that plugs into a black round thing on the side of my carb which means it's an electric choke.

Working from memory from yesterday but I believe the plate was straight up and down when it was at running temperature....not sure when the car has been sitting but I'll look when I get home. Luckily I found the "how to" instructions on the Holley website so hopefully I can get it adjusted.
Click to expand...
Hook that choke wire to the stator (S) terminal, NOT a hot with key-on wire off the ignition. The 12VAC signal coming off the stator is about 6-7 volts RMS and is plenty to run the choke. It's only hot when the engine is running.
 
I read the Holley directions and the directions for choke cutting off too soon sounded right up my alley...the symptoms sounded the same.

So I loosened the three screws on the choke and turned it back a couple of clicks. Holley suggested one click at a time but mine was running like it probably needed at least two clicks. I didn't want to wake everyone up starting the motor so I'll try starting it up tomorrow and see if that helps. If it's too much then I can always adjust it back half that amount.

I also ordered the Trick Flow pan today for the transmission and ordered a new dipstick and tube while I was at it.
 
"cmayna" said:
Let us know how the choke adjust works. A new Trickflow family member? booya!!!
Click to expand...

Yep, the new pan should be here in 3 -4 business days from yesterday according to Summit....if I'm lucky it will get her Friday then I can install it Friday night.

The old pan is just worn out. I pulled it off, the bolt holes appeared to be flush so I put a new gasket on it and hoped that would fix it...no such luck, even with putting thread sealer on the bolts. So I said screw it and shelled out the money for the Trick Flow. I figure with that pan I can torque the bolts down a little more with no worries.

I suspect the choke adjustment will be a trail and error kind of thing but I drove the car to work last Thursday and it was stalling out on me and even back firing once or twice when trying to make the corners in the parking garage at work until it warmed up...Holley said go one click at a time on the adjustment but I started with two to see what that does....
 
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