Doug,
Starter circuits can be lots trouble because of the weakest link
syndrome. The compression ratio doesn't have a great effect on cranking
once it starts to turn, the compression helps to move things along. Of
course, with a lumpy cam the compression at cranking is not all that
high anyhow.
I have found that most starter circuit problems, assuming the starter
and battery are quality units, are cables and ground circuits.
Resistance is your enemy, the voltage that is available after all the
resistance is overcome is what cranks the engine. I know that 12 volt
systems come with #4 & #6 cables, but I always use #1 cables on any
performance engine. If the cables are long (battery in trunk, etc.) even
larger cables may be needed. Another problem often overlooked is the
grounding of the battery. It should go directly to the engine block,
(never to an exhaust manifold bolt) then make certain that the starter
mounting is clean so that you get a good connect to the block for
ground. Certainly check all the connections to make sure that they are
not loose or dirty.
A volt meter can be put to use measuring volt drops through the circuit
to locate the problems. Put the meter on low scale (2V) hook the
positive lead of the meter on the battery post and the negative lead at
the starter motor positive connection and take a reading with the engine
cranking, ign off. Should be less than 0.5 volts. If you have a higher
reading start moving the negative lead back toward the battery positive
at each connection to locate the high resistance. Check the ground side
of the circuit in the same manner, placing the negative lead on the
battery negative and the positive lead on the starter case. The
acceptable reading here is 0.1 volt or less.
good Luck!!
Tom, Redding CA - #216 D/CC
Doug Anderson wrote:
>
> Hey folks;
>
> Been havin’ some serious “startin” problems with Boogie Woogie
> lately……. Why would my 332" 327 with 10-1 compression...act like "the
> battery was low" and grind over, you know like a typical chevvie thats got a
> "hot starter motor"??? something like; GRRuhhhhhh, GRRuhhhh, GRRuhhhin,
> GRRuhhhinn, Grinnddddd.....
>
> ..…it all started last weekend really....and can be downright embarrasin' at
> times it can. The whole setup in Boogiewoogie has 16,000 on it now. All
> was new or rebuilt when she was finished -except the 1 1/2 yr old battery.
> All was right with the world until last week. As of this writing I have
> replaced the starter with another rebuilt BIGBLOCK one, and bought a brand
> new 75 month 990 cold cranking amps battery from NAPA…..to the tune
> of about a hunnert an’ a ‘quata for the two….OW. -on my Collegggg
> allowance. OW.
>
> It ain’t no better boys. WHAT GIVES????? HELP !!?!!?
>
> here's what were'r workin' with;
>
> 332" motor 10-1 compression; 327 Chev 1966 block and ported 1.94intake,
> 461 heads
>
> Comp Cams hydraulic 285 degree, 490 lift rumpity cam
> (she maintains 17 " of vacuum during a coast condition at highway speeds...)
>
> A "stock" Chev point distributor circa 1966-69; with "the door."
> -inside is Mallory all the way. (brass contact cap & rotor with 5000mi.
> on'em?)
>
> Ignition is by MSD 6A box and coil. Points serve only as trigger.
> Dwell 29-30
> Vacuum advance hooked up normally, runs off manifold vacuum port on OFFY 3x2
> intake. Best quality MSD ‘spensive 8.8mm wires are used. And
> Autolite 303 plugs. –whiht maybe 3000 miles on them?
>
> Timing is set pretty normally. -Though I've always been a little perplexed
> as to WHY the marks never really seemed to be where they should when it is
> running good -and boy does she ever run GOOD! lotsa power. Just always
> timed’er by “by ear” and did fine. Been doin’ it that way all my life it
> seems like! Decent fuel mileage (14-16.5 mpg with a 3.5 rear gear at
> freeway speeds…) even with the cranky three deuces. Which are run
> progressively. No matter what I've tried it always runs generally rich
> -gets to your eyes at traffic lights with no hood on. -It runs and idles a
> bit differently every time it's used on a different day....-responsive all
> all get out though, and LOTS of fun. Just ask the regular “citizens” and
> the tailgating jerks in their Beemas’ , Mitsu’s, and Infinities….
>
> Jeesh, I’ve tried quite a few things….but I’m stumped with this.
> -Boy do I ever dealing with
> HATE “electronics” problems.
>
> Can anybody here give me a clue fellas? I sure need to try to get’er
> fixed by Thursday night as I need to take it on a 4-500 mile trip Friday
> mornin’ . And I GOTTA have TOTAL reliability for every start….
>
> One thing I tried was to remove the coil wire and try cranking it over –and
> she spins over freely like it ought’a -but with the wire back in place, it
> labors. -making you wonder if it will or if it won’t. You know?
> That tells me “timing” -so I checked….and it was right where it always
> is. Checked down low without vacuum, and at about 2500-3000 for total.
> And she runs like a bear when she is running, -and slows normally as you
> retard the spark and raises again as you advance it at idle….. normal
> stuff.
>
> When cranking and it’s straining, if you give it a squirt with the gas
> pedal, whoom! She starts! -USUALLY. I’d say the ol’ MSD box is doin’
> it’s job to fire it off at such a low RPM crankijng speed.
>
> So if that’s working fine, and the timing is reasonably right, the
> starters “new” and so’s the Battery, WHAT NEXT?
>
> ANY IDEAS greatly appreciated boys. I’ll be back online in the late
> morning. Oh, I forgot to say that I’ve had the new NAPA battery on
> trickle charge since 10 am because it did not show a “full” charge when the
> counterman checked it this morning when I purchased it. I did try
> starting the beast once before putting it on the charger (2 amp) and it
> acted about the same as it did before; with a slooooow grunting, begrudging
> start…. however, that said, could it be just co-incidence
> that because it was down a bit it would act that way too? (like the old
> battery did) Like maybe when I get home in an hour from Colleggg all
> will be right with the world again???? Naw I did’nt think so either…..
>
> Aw Hell, boys What gives?????
>
> ________________________________________________________________________
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