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AMC 360 cranks slow when hot

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304-dude View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 304-dude Quote  Post ReplyReply Direct Link To This Post Posted: Jul/09/2018 at 3:56pm
Originally posted by Trader Trader wrote:

Cool, forgot about the Dust Off trick.
Used to use it on robot speed controllers when they overheated to get them restarted.
Just turn a can of Dust Off upside down and spray the module (don't let liquid get on your fingers or in your eyes). That would cool the module down pretty quickly!


What ever you do, don't leave one of them blasted dust off cans in the car, especially in the summer.

In California it can be over 150+ degrees in a car when parked. Had a tech leave one in his console and It jetisoned out of the console and put a baseball sized hole in his windshield.

We used pro quality high pressure duster cans. They type you screw on a trigger nozzle. They have a wee smiley under the can, which is used to vent when too much pressure is formed within the can.

Them cans can freeze alcohol in seconds when upside down. It was a small gag to freeze in a coffee cup and watch it sputter and pop as room temp would not keep it in solid state. You could dump it in your cupped hand and it would be like pop rocks jumping out of your mouth.
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one bad rambler View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote one bad rambler Quote  Post ReplyReply Direct Link To This Post Posted: Jul/09/2018 at 7:24pm
Originally posted by billd billd wrote:

Every engine is different so it's not possible to compare what one runs vs. another engine, different build, different gas, different elevations, many factors, etc.  Those settings may be fine for your engine, but I have a couple that would self-destruct with those initial timing numbers, or i'd never get them started - at the very least, I'd LOSE horsepower going that far. My 360 is ok with 10 but any more and it balks and isn't as strong. My 390 I don't dare go that high initial - but it's got good timing total at speed.

Anyway, it does actually sound like a starter issue since his vacuum seems to match timing that's pretty close at least. 
You don't go into a parts store and buy a "new" starter these days. (unless it's for a 4.0 and then you could as of a year or so ago buy BRAND NEW, not reman, starters but that's another topic)
It's likely a remanufactured starter - and like the fellow who had to go to a third or fourth alternator to get his issues resolved, just because it's from a parts store and guaranteed doesn't mean it's good.
I could show some of the alternators and starters I have on my shelves that are "reman" and some were only on the car for days, weeks at the most - and it's scary what I see inside 'em, or even outside of them. 
This is but one reason I do electric parts myself and refuse to rely on parts store reman stuff when I can totally avoid it. 
Agreed...Both of those engines run mech. advance only with a curve tailored to that specific engine... 
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FSJunkie View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote FSJunkie Quote  Post ReplyReply Direct Link To This Post Posted: Jul/09/2018 at 10:54pm
Good cables: at least 4 AWG but 2 AWG is better. Keep the cables as short as possible. 
Clean and tight cable connections.
Good starter relay. They get old and build up resistance inside. 
Good starter relay ground.
Good starter to engine block ground.
Good engine block ground to battery. 

Starters normally don't get appreciably slower when they are hot unless they are cooked by a set or headers or have something wrong internally. A good starter far from the exhaust system does not have that problem.
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Boris Badanov View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Boris Badanov Quote  Post ReplyReply Direct Link To This Post Posted: Jul/10/2018 at 5:13am
In my experience I have never had an AMC V8 give hard hot starts
unless the starter is NG or over heated.

Other possibilities?

Bad timing, easy to diagnose, disconnect the coil and crank it.

Excessive compression?

Poor ring fitting?

Poor piston fitting?

localized severe over heat?

Severely over heated intake heat stove?

Bad cables are a bit of a reach, but they should screw up cold as well.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Lucas660 Quote  Post ReplyReply Direct Link To This Post Posted: Jul/10/2018 at 7:06am
Loctite makes a freeze and release spray that you could check the ignition module with. I think crc makes one too. Personally I would try jumper cables in between connections to test them. Run them in parallel with what's there. If it solves the problem replace that cable.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Boris Badanov Quote  Post ReplyReply Direct Link To This Post Posted: Jul/10/2018 at 6:10pm
If it is ignition related simply disable the spark in some way and crank it.
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jeep9393guy View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jeep9393guy Quote  Post ReplyReply Direct Link To This Post Posted: Jul/11/2018 at 4:10am
Had the battery tested , turns out to be junk . God a new deka 800 cca . Ill see what happens the weekend .

  Ill let you know the results .
  Frank
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jeep9393guy Quote  Post ReplyReply Direct Link To This Post Posted: Jul/14/2018 at 10:49am
Looks like we have fixed it ! So far so good . Put in the new Battery cleaned every batt.cable ,put the factory cap and rotor on the distubuter ( had a two peace ford large cap and rotor ) stock ignition wires . set timing to 10BTDC so far starts hot good !
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