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phenom08
09-04-2019, 04:08 PM
Motor starts almost instantly when it's cold. Was going on last year kinda chalked it up to worn rings etc. Now fresh it's no better. Motor is 14 to 1 compression on sunoco hcr. After hotlaps when having to go back out to qualify just turns over and over with ignition on. If u push car with 4 wheeler it starts soon as pull it in direct drive. Any ideas?

JustAddDirt
09-12-2019, 12:18 PM
12volt battery or 16v?
maybe cranking it takes all the electrical system has to crank, and not supplying ignition box with good power

how much fuel is in the float bowls?

phenom08
09-12-2019, 07:07 PM
12 volt battery put new one in few races ago no different. Float levels are half way up the sight glass

JustAddDirt
09-16-2019, 08:23 AM
have you tried getting engine cranking with the ignition switch off, and then flipping it up to get it to start?

Krooser
09-16-2019, 12:21 PM
How about trying a stronger starter? Ground everything to the chassis. Check the starter ground to the block or bellhousing.

ZERO25
09-16-2019, 05:26 PM
Sounds like a timing issue. Our engine builder would not allow us to lock out the dist timing.

phenom08
09-17-2019, 07:29 PM
If I spin it with the ignition off it sounds like its gonna break the nose of the starter. The dist is locked

SRXSRULE
09-17-2019, 08:23 PM
Is it only a hard starting issue, or does the performance go down any when its hot?

You might want to check the valve lash when its hot and make sure your not hanging any valves open when its hot. At cranking RPM it doesnt take much to create a problem. Push starting it cranks it over much faster

phenom08
09-18-2019, 09:40 AM
Motor runs fine once it starts, we did loosen the valves up alittle the other week to see if that help, but it did not

JustAddDirt
09-18-2019, 10:44 AM
16 volt battery would more than likely fix the issue.
First thing I would try would be.
Ground starter to chassis. (use starter mounting bolt to a midplate bolt), make sure you have paint or powder coat cleaned off.

but if you stick with the 12v battery
try backing the timing down 4-6 degrees and see what it does.
if it sounds like it is going to break the nose off starter, as you indicated, the timing may be too far advanced.

billetbirdcage
09-18-2019, 02:06 PM
Is this with an MSD box and dizzy? Probably not it but worth a check:

Roll/bump engine over to 32 degree's (what ever you have timing set for) on #1 cylinder on compression and remove cap and see how close the rotor is to actually lining up with the #1 terminal on the cap. If it's way off, like close to half way between 2 terminals and not directly at #1, then you may have the polarity backwards on the MSD box.

Switch the wires on the distributor around and use most retarded for anologe box and most advanced for a digital box.

phenom08
09-19-2019, 12:45 PM
Yea, were running msd distributor and box. Thanks I'll check that this evening

JustAddDirt
09-30-2019, 10:55 AM
if the MSD factory plugs are still being used for the plug ins it is more than likely correct, unless someone has de-pinned them and changed stuff for some reason.

if they are using weather-pac terminal ends, or any other connector I would question the polarity for sure