Slow to start when hot
Thread Starter
Advanced
Joined: Oct 2002
Posts: 52
Likes: 0
From: wellington fl
Slow to start when hot
I have a 77 vet which starts fine when cold. But once it gets hot it turns over very slowly. I have replace the battery. Timing is set at 12 degrees. I have a adjustable advance also on the car. I also have headers. Car runs about 160 degrees. Any suggestions. Thanks
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Check the condition of the battery cables. There are 3. The positive cable from the battery to the starter, the battery ground to the frame under the battery box, and the short cable between the right motor mount stand on the frame and the block. Look at connections, cable resistance, and look for internal corrosion in the cables. The internal corrosion is the tough one to find. Look for damage in the insulation where moisture can get into the cable, and any signs of a white or green colored powder either the length of the cable or at the ends.
Racer
Joined: Jan 2014
Posts: 425
Likes: 3
From: Jefferson City Missouri
Sounds like a starter issue. Headers are great for cooking starters. When I put headers on my old Ford, the starter went out a few weeks later. Boy did it crank faster, even when cold. I had no clue it was getting so slow over time.
Melting Slicks
Joined: Dec 2009
Posts: 3,233
Likes: 657
From: Thunder Bay
If originality isn't important to you, install one of the new high torque gear reduction mini-starters. They will work even when the battery is weak and the engine is hot. Huge improvement over the old style. My '79 used the starter for a '96 full size truck. Not sure what you will need for your '77.
Melting Slicks
Joined: Oct 2011
Posts: 3,453
Likes: 67
From: Midland Ontario
NCM Sinkhole Donor
Definitely check the cables, as has been mentioned, but it sure sounds like a heat soak situation.
Pro
Joined: Aug 2000
Posts: 610
Likes: 168
From: Vancouver B.C.
I would focus on cables first as well. Free. Perform a drop voltage test. Very simple. Google and you will find lots of instructions on drop voltage test procedures. As mentioned if corrosion is inside the cables, this test will reveal it. If all OK, then heat soaked starter likely the cause.
Melting Slicks
Joined: Mar 2008
Posts: 2,989
Likes: 198
From: Meriden CT
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
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
