Hard cranking when hot.

[john.thompson068]

Hard cranking when hot

On to the next issue. I take out a spark plug. Put my finger on the hole. Crank the motor over until the compression blows my finger off. Then manually crank the motor until the timing mark lines up with the hole in the timing tab. Then I rotate the distributor housing until one paddle of the reluctor wheel lines up with the pick up. It is now set at zero degrees. Then I turn the housing clockwise 3/16 of a turn and the car fires right up. It is at 15* timing like this according to my timing light. I let the car warm up to 190 degrees and then I shut it off and restart it and it has a slow cranking problem because it is hot. It only does this when it is hot. I backed the timing all the way down to 9* in one or two degree increments and it still had the hard cranking problem. I had to turn the idle up as I moved the timing down, and when it got to 9* it dieseled when I turned it off so that was obviously too little timing plus it still had the hard cranking problem. I just set it back to where the timing light shows 15*. What am I doing wrong? How can I get my car to crank right up when it is hot.


Just to clarify, the issue is only the starter motor turning slow and starting and stopping and then turning slowly when hot. The motor always starts right up after the starter labors for those few seconds. The motor is a 440 with 10.5:1 compression, and has a mini starter and a brand new battery. The battery is in the trunk, and has a 1/0 guage welding cable which was professionally made and runs from the battery to the solenoid, which is also in the trunk, and to the starter. I use the same size cable for the ground. The battery has 8 guage charging wires, and has about 850 CCAs. I attached a picture of my setup. Before everything gets hot, the starter turns over very quickly and the motor fires instantly.


In the starter pictures, you can see that there is plenty of room around the top the starter. Only the number three and number five pipes come within an inch or so of the starter on the sides and along the bottom. If this was a heat soaked starter problem, wouldn't everyone on this board with headers have the same problem? I don't want to just assume it is a heat soaked starter problem if not everyone else with similar header and starter combinations are not having the same problem. As you can see, the headers are Hooker Competition and they have 1 7/8 primaries.

So is this a timing issue, or a heat soaked starter issue?

 

[SUPERSTOCKRACER]

from my experience your battery doesnt put out enough. swap out for another battery.then see if it works. i had the same problem also,

 

[john.thompson068]

I don't have another battery and just paid $104 dollars for this one. There was one battery there that had like 1000 CCA if that is what you are referring to, but that is the most CCA I have ever seen. I also read something on the Internet that said something about the more CCA's the shorter the battery life, so I figured I would go with what my Duralast Platinum had, and my Monte Carlo has. Both of those batteries halve about 850 CCA, which I thought should be more than sufficient. I guess I could use my jumper cables tomorrow and hook up my Monte Carlo battery to my Satellite's battery and see if that makes a difference.

 

[brandon64]

sounds like cam timing is too far advanced, what do you have it set at?

 

[Southernman]

I see a few things that are not working in your favor:

1 - Your ground is bolted to sheet metal in the back versus the frame.
2 - The solenoid is mounted in the back, which means, during switching, there's a long path for electrons to travel. It's also grounded to sheet metal - far from the starter. Remember, when hot, resistance goes up.
3 - In almost every trunk mounted battery I've ever ran, I've always had to use one size larger cable from the solenoid to the starter - than the cable coming from the battery. The reason:

The solenoid acts as a resistor in the circuit (again, under heated conditions you will lose a significant amount of current to heat), by increasing the size of the cable between the solenoid and starter, you negate the effect from both.

Keep the solenoid as close to the starter as possible, and use one size larger from the solenoid to starter than you use from battery to solenoid. Also, don't forget to ground your block to the frame at the front. Grounding will go a long way to relieving the symptoms you described.

Again, that's been my experience. Let us know what you find.

Southernman

 

[john.thompson068]

sounds like cam timing is too far advanced, what do you have it set at?

I have no idea about cam timing since I had a shop put it together.

 

[Ron 73]

Id try a full size starter, high TQ starter in it, and check all the grounds..

 

[Jonnyuma]

I think Southernman knows his electrons.

 

[john.thompson068]

I was told the solenoid is in the trunk to keep from having a live wire running through the entire car. Also, the battery cable size was recommended to me by MADD electrical who I bought the kit from. The kit turned out to be a great investment because the kit and the wiring book I bought from them made me really knowledgeable about wiring. It also had all the wires I needed and the fusible links and directions. Now when I install relays for the headlights, I won't need his kit. I will just buy the relays from the parts store.


Not only did I install that relocation kit, but I also rewired my alternator wiring. I called the guy at MADD about something and he told me how to improve my cars wiring. Following his advice, I ran the 8 guage wire to a wiring terminal included in the kit. Then drilled out the factory wire connector on the firewall and ran the 8 guage wires straight through to the main power wire in the dash harness. I crimped and soldered everything finishing with electrical tape and heat shrink. Then there is a separate 8 guage wire which runs from the starter relay back to the battery. My understanding is the blue wire runs from the starter relay back to the solenoid and tells the solenoid when to send power through that huge wire to the starter.


I made sure all my grounds are to bare metal, and I have the same 1/0 guage wire making two grounds from my motor to the underside of the car.


There is one thing I forgot to mention. It does not do it every time. If I start and shut the car off 5 times it may only do it 3 times slow, and the other two times it starts right away.

 

[Jonnyuma]

Mine does the same thing, pretty much exactly. The only things our cars have in common is that they are both Mopars and have 4 wheels. I'm gonna leave my battery where it is for now and wrap my starter in a heat shield of some kind. If it works on my stock-ish setup maybe it will help your highly modified one. If I can find some material locally I'm gonna do it today.

If it's a cam timing issue, well, that's different altogether.

 

[john.thompson068]

Johnny, Napa and Advance both have the same heat shield wrap as what is available from Jegs. It seems that the starter would absorb more heat from being directly bolted to the transmission than from the exhaust. I can put my bare hand very close to the header tubes and as long as I do not actually touch the header, my hand is not burning at all. So I am having a difficult time believing right now that the headers could be causing my starter to become so much hotter than whatever it normally would become that it sometimes struggles to start. The fact that it only struggles some of the times is also suspect. And that many other members have the exact same setup as mine and they are not having any problem. And that my car only sometimes cranks slow when hot. My next thread soon will be to discuss the way in which I have grounded my battery, solenoid, and engine. Seems there might be a problem with my grounds to sheet metal and I need to make sure I am entirely clear on what needs to be done to fix this before I go drilling any more holes. Let us know as soon as you test out the car with the heat wrap.

 

[john.thompson068]

Southernman, I have identified one of my grounds that needs to be improved. It is the negative off of the battery. While I scraped down to bare metal on the inside of the trunk, the washer under the car is laying on top of the undercoating. Today I will scrape the undercoating down to bare metal and hopefully that solves my problem.