Ames Performance Engineering - Click Here!

POCI LINKS

2017 Annual Convention - Click Here! Visit the POCI Club Store - Click Here! Join us on Facebook - Click Here! Join us on Pinterest - Click Here! Vist the POMARC - Click Here!

Advertise on POCI.org
Page 1 of 2 12 LastLast
Results 1 to 10 of 12
  1. #1
    Join Date
    Nov 2008
    Location
    Southeast MI
    Posts
    100

    Question Hard Start/No Start When Engine is Hot....

    I am sure many folks have had this happen, as have I. So I think this would be a good place to document the solution.

    I recently had a situation where my 455 in my '72 Lemans would not start or was very hard to start when it was hot or warm. It hardly cranks, as if the battery was low on power. I run strictly 10W-30 oil in it. The car is driven all car show season and the oil is changed every 3000 miles. The battery is a brand new Sears Diehard with a 960 CCA rating. I use a Battery Tender to keep the car charged when the car is not in use. I replaced the starter but I don't think that was the real problem in retrospect.

    So I am asking the wise mechanics out there what they think the problem can be, what the possible causes are, and the solutions? Initial timing wrong? Starter? Vapor lock? Alternator? Bad battery cables?
    Last edited by frosty; May 5th, 2011 at 11:40.

  2. #2
    Join Date
    Feb 2010
    Location
    Downers Grove,Illinois
    Posts
    4

    Default

    I am not a certified mechanic. That said...I currently have the same issue with a totally stock `75 Formula 350. This is a very common complaint for V-8 Pontiac owners...especially those with headers rather than stock exhaust manifolds. This is almost always a heat issue as our exhaust systems run much too close to the starter solenoid. I understand that some hobbyists are now utilizing remote solenoid systems to avoid this "heat-sink" problem.You can also wrap the headers with insulation sold for that purpose.

    If your issue was vapor-lock the engine would eventually start in an overly rich state...running rough initially...and most likely smoking at the tail-pipe due to unspent fuel.

    Noting that your vehicle is not stock, ( 455 in a `72 Le Mans ) it is slightly possible but not very likely that your harmonic balancer has spun on its elastomer or the timing plate is not in the proper location...both of which could provide a false reading when the amount of advance is checked with a timing light.

    Bad Battery Cables are a real long-shot...but I usually change mine on a regularly driven vehicle at 5 year intervals. ( Rust Belt Location ! )

    Hope this helps...Best of Luck !
    Last edited by TommyO; May 6th, 2011 at 14:28.

  3. #3
    Join Date
    Nov 2008
    Location
    Southeast MI
    Posts
    100

    Default

    I just found this article from High Performance Pontiac, the December 2009 issue. Sounds like the problem lies with the stock Delco style starter is getting heat saturated that the solenoid is not engaging properly and it won't engage without a high CCA battery or it cools off. The cure seems to be a modern mini-torque starter. The problem is that these suckers just are not very cheap, $170-400 depending on stock to race-only versions. Wow! I think I will also invest in a heat sheild too.

    http://www.highperformancepontiac.co...ter/index.html

  4. #4
    Join Date
    Nov 2008
    Location
    Villa Rica GA
    Posts
    51

    Default

    Here is a possible fix. Experience: On older Pontiacs such as the early 60s cars, the ignition switch contacts would become corroded and not allow enough voltage to reach the starter solenoid thus not pulling it in solidly and the engine didn't turn over fast enough to start. My cure for this was to add an intermediate relay between the ignition switch and the starter solenoid. Wire it in so that the switch picks up the relay and the relay contacts feed the starter solenoid with a good 12 volts plus. Use a 30 amp contact rated relay. The relay uses a very small amount of current to pick it up so little voltage drop occurs, so even if the ignition switch is somewhat corroded it will still supply enough voltage to pick up the intermediate relay. You can hide the relay so that the engine bay still appears stock. This might also be considered by those who wish to preserve their original ignition switch's longevity.
    One of my cars was a 1962 GP in which the ignition switch was almost beyond useful operation (the engine would not turn over) and the above fix worked beautifully and still does after more than 9 years of use by the man who bought that car from me.
    Frank

  5. #5
    Join Date
    Oct 2008
    Location
    Portland In
    Posts
    781

    Default

    I run 0 or 1 guage cables with an OE high torque starter with good luck. I am not a fan of mini starters unless space is a problem. The major reason for the addition of the ford style solenoid was heat soak of the starter mounted solenoid. A simple starter wrap or shield with the above cables and a good battery will acheive the same end result and have less connections to have issues with.

    Mike

  6. Default

    I have used FHummel's suggestion for years for not only the starter but lights, and other high current systems. Running high amp loads through these old switches is not a good idea.

  7. #7
    Join Date
    Nov 2008
    Location
    Southeast MI
    Posts
    100

    Default

    Mike,

    Do you make your own battery cables or do you buy them somewhere? If you buy them, where do you get them? Do you use top post or side post battery connections?

  8. #8

    Default

    ok I had<--HAD that same problem. Mine is a 1969 Custom "S" built 350 headers do run very close to starter. Bought and installed a high torque mini starter...starts everytime hot or cold. $170.00 but worth every penny!!

  9. #9

    Default

    install ford type starter solenoid in parallel with existing Delco solenoid. then only wire going to starter is a battery cable. no smaller gauge wires which now go to ford solenoid (which is just a high amp relay)

  10. #10
    Join Date
    Nov 2008
    Location
    Southeast MI
    Posts
    100

    Default

    Well, I have purchased a high torque mini-starter from Summit Racing for it since I am not too interested in putting another switch into the system. I need time to install it though, perhaps the Easter holiday weekend I will have some spare time. I replaced the battery cables in 2005 with OER stuff, so corrosion on the wires is at a minimuim. I cleaned the other existing starter contact wires when I replaced the battery cables too. I also put a dab of dilectric grease on all the contacts.

    Someone else suggested that this could also be the result of incorrect initial engine timing? I am not sure I agree with that since it starts fine stone cold. Anyone got any comments on that one?

Similar Threads

  1. 49 Chieftain now will not start
    By drkarr in forum Pontiac 1926 - 1960
    Replies: 1
    Last Post: March 5th, 2014, 20:06
  2. 66 gp does not start with key
    By 056133 in forum Pontiac 1961 - 1979
    Replies: 3
    Last Post: November 7th, 2013, 12:04
  3. 1939 straight 8 no hot start
    By NateUlery in forum Pontiac 1926 - 1960
    Replies: 2
    Last Post: September 21st, 2013, 18:03
  4. I'm new here ... where to start ...
    By GaWajn in forum Pontiac 1926 - 1960
    Replies: 6
    Last Post: December 31st, 2011, 00:38
  5. Hard Start Hot 70 Catalina 350
    By melrose_garage_inc in forum Pontiac 1961 - 1979
    Replies: 3
    Last Post: September 30th, 2009, 10:49

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •