Engine starts hard when hot. - Pontiac GTO Forum
User Tag List

 2Likes
Reply
 
LinkBack Thread Tools Display Modes
post #1 of 16 (permalink) Old 04-12-2019, 03:58 PM Thread Starter
 
Join Date: Aug 2006
Posts: 42
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
Engine starts hard when hot.

Started my 67 after many years yesterday and it cranked over very easy then when the engine warmed up it was very difficult to start.Battery is brand new and super duty 1000 amps, Thanks for any help
keiko is offline  
Sponsored Links
Advertisement
 
post #2 of 16 (permalink) Old 04-12-2019, 04:01 PM
64-67 Expert
 
geeteeohguy's Avatar
 
Join Date: Feb 2008
Location: Fresno, California
Posts: 8,558
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 119 Post(s)
Possible: high resistance in starter windings, high resistance in battery cables, overly advanced timing due to sticking centrifugal weights caused by gummed up distributor shaft. (Very common on cars that have sat awhile!)
Bobbyg and PontiacJim like this.
geeteeohguy is offline  
post #3 of 16 (permalink) Old 04-12-2019, 08:40 PM
 
PontiacJim's Avatar
 
Join Date: Dec 2012
Location: Gastonia, NC - Born & raised in Connecticut - 31 years
Posts: 3,728
Mentioned: 1 Post(s)
Tagged: 1 Thread(s)
Quoted: 404 Post(s)
Garage
Quote:
Originally Posted by keiko View Post
Started my 67 after many years yesterday and it cranked over very easy then when the engine warmed up it was very difficult to start.Battery is brand new and super duty 1000 amps, Thanks for any help
Carb might be dried out from setting so long and needs a good rebuild - new gaskets, accelerator pump, needle & seat. You could have gas dripping into the intake and this would also cause a hard start problem - kinda like flooding the engine.
PontiacJim is online now  
 
post #4 of 16 (permalink) Old 04-13-2019, 03:53 AM
 
Anderslober's Avatar
 
Join Date: Mar 2018
Posts: 99
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 24 Post(s)
Heat soaking of starter........a known Pontiac problem.....my 78 TA does this.......just let it cool down for 20-30 minutes....then it starts fine again.
Anderslober is offline  
post #5 of 16 (permalink) Old 04-13-2019, 12:15 PM Thread Starter
 
Join Date: Aug 2006
Posts: 42
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
could this be a problem due to the timing be to far advanced ? if so which way would I turn the distributor to retard it ? Thanks
keiko is offline  
post #6 of 16 (permalink) Old 04-13-2019, 07:28 PM
 
Lemans guy's Avatar
 
Join Date: Oct 2014
Location: Nashville, Tennessee
Posts: 765
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 79 Post(s)
Pontiac distributors turn CCW........you turn against rotation to advance and with rotation to retard.....

But I doubt it is timing as timing does not change between a cold and hot start,...unless a condition like GTO guy said with sticking weights.

Rather your car started fine cold,....that means the choke and fast idle cam were able to give it a rich enough mixture so it fired right up...

But all those systems are not supposed to be in play on a hot start,.....so Like PJ said a gummed up carb, idle mixture set a bit too lean....

Also make sure the choke and fast idle cam release, because if they are stuck....the mixture will be too rich when hot and the car will not start because it is flooded,. Will smoke and idle rough if they stay engaged..

Could also be electrical resistance that does not occur until hot....

To begin with use some carb cleaner on that carb, for a quick clean, You still should rebuild it after 10 years. Look under the distributor cap and check weights and springs, a spring could be off,...and get fresh gasoline.

Leave that timing alone for the moment, it started,....investigate some other places or you will get hung up,....you can check it with a timing light.....to see where it is without moving it.
Lemans guy is offline  
post #7 of 16 (permalink) Old 04-14-2019, 02:52 PM
64-67 Expert
 
geeteeohguy's Avatar
 
Join Date: Feb 2008
Location: Fresno, California
Posts: 8,558
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 119 Post(s)
You can rule out the sticking distributor weights in 2 minutes next time it acts up. Simply pull the dist cap and see if you can manually turn the rotor. If you can, it was stuck in the mechanical position due to a gummed up distributor shaft. Very common. If this is NOT the issue, at least you've eliminated it. From your description, it is a slow cranking when hot issue, correct? NOT a crank and crank and crank, but no start issue?
geeteeohguy is offline  
post #8 of 16 (permalink) Old 04-15-2019, 10:37 AM Thread Starter
 
Join Date: Aug 2006
Posts: 42
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
Quote:
Originally Posted by geeteeohguy View Post
You can rule out the sticking distributor weights in 2 minutes next time it acts up. Simply pull the dist cap and see if you can manually turn the rotor. If you can, it was stuck in the mechanical position due to a gummed up distributor shaft. Very common. If this is NOT the issue, at least you've eliminated it. From your description, it is a slow cranking when hot issue, correct? NOT a crank and crank and crank, but no start issue?
Nope not a starting issue, Spins like hell when cold but when I turn it off and immediately try to re start it when hot it bogs down, almost like there is to much compression to let the pistons spin (I know this is not the case but trying to explain what it does)
keiko is offline  
post #9 of 16 (permalink) Old 04-15-2019, 11:30 AM
 
Join Date: Jan 2019
Location: Connecticut
Posts: 44
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 7 Post(s)
Garage
Do you have headers on the car? I experienced this on my 70 skylark after I installed headers. The starter got too hot and acted like the compression was super high. Buy a heat wrap and wrap the starter. Should take care of the problem.

God, Country, Cars
gmjunkie is offline  
post #10 of 16 (permalink) Old 04-15-2019, 11:44 AM
 
1968gto421's Avatar
 
Join Date: Mar 2014
Location: Travelers Rest, South Carolina
Posts: 766
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 72 Post(s)
There are many threads on this forum dealing with this problem. I used the google custom search in the upper right corner of the screen. Anyway here is an example of thigs I found. Check this link out:

https://www.gtoforum.com/f50/69-gto-...en-hot-107754/

Best of luck resolving this!
1968gto421 is online now  
Sponsored Links
Advertisement
 
Reply

  Pontiac GTO Forum > The 1964-1974 Pontiac Tempest, Lemans & GTO > 1964-1974 Tempest, Lemans & GTO General Discussion

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Pontiac GTO Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
Engine starts/idles fine for about 15 sec and then... aeconfidential 1964-1974 Tempest, LeMans & GTO Engine Tuning and High Performance 2 04-06-2016 11:15 AM
Hard starting when hot(ish) gjones 1964-1974 Tempest, LeMans & GTO Technical and Electrical Wiring 10 05-02-2013 11:59 PM
Hot hot hot gjones 1964-1974 Tempest, LeMans & GTO Technical and Electrical Wiring 23 03-26-2013 08:44 PM
how hot its to hot? tyler t 1964-1974 Tempest, LeMans & GTO Technical and Electrical Wiring 11 02-05-2011 01:35 PM
How hot is too hot? michaelskier 2004-2006 GTO General Discussion 14 11-23-2005 02:14 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome