351M
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351M
Just finshed swaping my 300-6 for a 351M.I rebuilt it myself (my first) it runs great but when it gets hot and I kill it she will beary turn over, but she always starts.I have ajusted the timming three or four times, but she wont start or she will run bad.Thanks for any help.
Fleet Mechanic
Joined: Jul 1999
Posts: 1,360
Likes: 1
From: Iowa
351M
If your motor is newly rebuilt, it will be tight because all the clearances are back to spec and tight. In time, your motor will "loosen up" as it gets broke in. The horsepower will pick up, it'll run smoother, cooler, and your gas mileage will get better. If you are using an old battery or starter, they could be having a hard time pushing a fresh motor.
Are you running headers? They will direct much more heat on your starter, and a cool starter always works better than a hot one. Is your battery big enough? I won't use anything smaller than an 800 cca Battery on my 390.
Also, a hot engine requires more amps to turn over. Good luck.
Jason
Are you running headers? They will direct much more heat on your starter, and a cool starter always works better than a hot one. Is your battery big enough? I won't use anything smaller than an 800 cca Battery on my 390.
Also, a hot engine requires more amps to turn over. Good luck.
Jason
Senior User
Joined: Jun 1999
Posts: 366
Likes: 0
From: saramento usa
351M
It sounds a lot like the starter is giving out when the engine gets hot (common for an old starter). I'm running a 351W with headers and I wrapped my starter with a heat sheild. You can check the pulling amps when you turn it over. I believe my mechanic said it should only pull about 200 amps during crank.
Even after I replaced my starter, I seemed to have the same problem, except it was inconsistent. I found out that I had a bad cell in my brand new battery so when the engine got hot and started drawing a few more amps than normal....Well, replaced the battery and everything works great!
Slik
> If your motor is newly rebuilt,
>it will be tight because all
>the clearances are back to spec
>and tight. In time, your motor
>will "loosen up" as it gets
>broke in. The horsepower will pick
>up, it'll run smoother, cooler, and
>your gas mileage will get better.
>If you are using an old
>battery or starter, they could be
>having a hard time pushing a
>fresh motor. Are you running
>headers? They will direct much more
>heat on your starter, and a
>cool starter always works better than
>a hot one. Is your battery
>big enough? I won't use anything
>smaller than an 800 cca Battery
>on my 390. Also,
>a hot engine requires more amps
>to turn over. Good luck.
>Jason
Even after I replaced my starter, I seemed to have the same problem, except it was inconsistent. I found out that I had a bad cell in my brand new battery so when the engine got hot and started drawing a few more amps than normal....Well, replaced the battery and everything works great!
Slik
> If your motor is newly rebuilt,
>it will be tight because all
>the clearances are back to spec
>and tight. In time, your motor
>will "loosen up" as it gets
>broke in. The horsepower will pick
>up, it'll run smoother, cooler, and
>your gas mileage will get better.
>If you are using an old
>battery or starter, they could be
>having a hard time pushing a
>fresh motor. Are you running
>headers? They will direct much more
>heat on your starter, and a
>cool starter always works better than
>a hot one. Is your battery
>big enough? I won't use anything
>smaller than an 800 cca Battery
>on my 390. Also,
>a hot engine requires more amps
>to turn over. Good luck.
>Jason
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