Hard Starting Holley
Thread Starter
Racer
Joined: Apr 2006
Posts: 322
Likes: 0
From: Rockford MI
Hard Starting Holley
Hi Guys, I've got a Holley 4175 spread bore with an electric choke on my stock 78 L-48. It starts good cold and also when the engine is hot up to about 20 mins after I shut it down. If it sits much more than 20 mins it starts really hard. Have to crank it alot and end up applying about half throttle to get it started, it also smokes pretty good once it is started. Is this a common holley electric choke issue or is there any adjustments I could make?
Thanks
Thanks
Le Mans Master
Joined: Nov 2008
Posts: 5,691
Likes: 12
From: columbus oh
Hi Guys, I've got a Holley 4175 spread bore with an electric choke on my stock 78 L-48. It starts good cold and also when the engine is hot up to about 20 mins after I shut it down. If it sits much more than 20 mins it starts really hard. Have to crank it alot and end up applying about half throttle to get it started, it also smokes pretty good once it is started. Is this a common holley electric choke issue or is there any adjustments I could make?
Thanks
Thanks
Burning Brakes
Joined: Aug 2005
Posts: 1,164
Likes: 1
From: Europe, France
You can use a thicker gasket between carb and manifold and see if it cures the problem or not. Try at least 1/4" thick.
Try to put a hand on the fuel bowls when your engine is hot. If it's so hot you can't keep your hand on them, that's the cause of your problem.
Mr Gasket, Holley, Edelbrock and others make special ( called heat insulator or heat shield or heat dissipaters ) gaskets for this purpose, but you must first check if you have enough clearance between your air cleaner and the hood.
A carb spacer does the same thing, actually it is more effective, but it's even higher, at least 1/2" or 1"...
Last edited by 73StreetRace; Jun 9, 2009 at 07:51 AM.
Le Mans Master
Joined: Jan 2006
Posts: 6,504
Likes: 139
From: Butler Pa
Sounds to me that after 20 min. the choke is closing again but the engine is still hot. A closed choke on a hot engine will flood it. Thats why you have to hold the throttle open to get it to start, and hence all the smoke.
I never had any luck with Holley electric chokes.
I never had any luck with Holley electric chokes.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Intermediate
Joined: May 2009
Posts: 39
Likes: 0
From: Montgomery TX
Had the same issue. Checked the floats.....ok. Checked/adjusted the electic choke....no change. Put a heat insulated gasket under the carb......and.....presto!
But be careful. They are thick. If you do this, make sure you have hood clearance for your set up.
zmanc3
But be careful. They are thick. If you do this, make sure you have hood clearance for your set up.
zmanc3
Drifting
Joined: Apr 2007
Posts: 1,970
Likes: 45
From: Cameron Park CA
Google "Holley Electric Choke", you'll find a lot of information on how to adjust yours. I have one, and while it's not as good as an intake manifold heated divorced choke, it works well. I don't have exhaust cross-over heat, so an electric choke was the only solution, other than a manual choke which is a non-starter for me.
You can adjust the rate it comes on by turning the black housing to Rich or Lean, and you adjust the fast idle speed with the idle speed adjusting screw. With a lot of fiddling with it on a cold motor, you can get it right!
You can adjust the rate it comes on by turning the black housing to Rich or Lean, and you adjust the fast idle speed with the idle speed adjusting screw. With a lot of fiddling with it on a cold motor, you can get it right!
Burning Brakes
Joined: Aug 2005
Posts: 1,164
Likes: 1
From: Europe, France
It is made of 3 gaskets and 2 aluminium sheets
Recently, I made my own heat dissipator, and it works very well, even if it is only 1/4" thick too.
Last edited by 73StreetRace; Jun 12, 2009 at 06:03 AM.
