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  • 2005 - 2014 S-197 Mustang -General/Talk-
  • 2005 - 2009 Specific Tech

New engine won't turn over

  • Thread starter Thread starter atv4fun
  • Start date Start date Jan 10, 2012
A

atv4fun

New Member
Jul 20, 2009
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Jan 10, 2012
#1
  • Jan 10, 2012
  • #1
I've built and installed a stroked 4.6l with a 9.5:1 compression ratio. The build went well until the engine was reinstalled. The engine will not turn over with the plugs installed. It turns over like mad with the plugs out. I've had the battery and starter tested, they checkout fine. I'm running out of ideas and things to check. I'm hoping that someone out there might have some other things I should check. Thanks!
 

jpplaw

Member
Jan 14, 2009
185
3
18
Jan 10, 2012
#2
  • Jan 10, 2012
  • #2
Valves opening?
 

SpartaPerformance

10 Year Member
Nov 5, 2006
2,517
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89
Long Island NY
Jan 10, 2012
#3
  • Jan 10, 2012
  • #3
When you say it doesn't turn over what exactly do you mean?
 
A

atv4fun

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Jan 11, 2012
#4
  • Jan 11, 2012
  • #4
jpplaw said:
Valves opening?
Click to expand...
Yeah, I can only assume the valves are opening, I can watch the cams turning.
 
A

atv4fun

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Jul 20, 2009
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Jan 11, 2012
#5
  • Jan 11, 2012
  • #5
SpartaPerformance said:
When you say it doesn't turn over what exactly do you mean?
Click to expand...

The starter will not spin the motor with the plugs in. It will spin all day with the plugs out. I'm checking now to verify I've got the correct plugs.
 

SpartaPerformance

10 Year Member
Nov 5, 2006
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Long Island NY
Jan 11, 2012
#6
  • Jan 11, 2012
  • #6
Sounds like timing may be off, who put the motor together?
 

jpplaw

Member
Jan 14, 2009
185
3
18
Jan 11, 2012
#7
  • Jan 11, 2012
  • #7
Can you turn it over using a breaker bar with the plugs in?
 
A

atv4fun

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Jul 20, 2009
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#8
  • Jan 11, 2012
  • #8
jpplaw said:
Can you turn it over using a breaker bar with the plugs in?
Click to expand...

No it won't turn over with a breaker bar when the plugs are in. With the plugs out I can turn it with a regular 1/2 ratchet, it's not easy but it will turn.
 
A

atv4fun

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Jul 20, 2009
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Jan 11, 2012
#9
  • Jan 11, 2012
  • #9
It's been suggested that I reinstall the plugs, one plug at a time, turning the motor by hand between each plug. When it stops turning that might indicate the cylinder that has an issue. Seems like a logical approach, but time consuming, so it will have to wait for the weekend.
 
A

atv4fun

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Jul 20, 2009
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Jan 15, 2012
#10
  • Jan 15, 2012
  • #10
I went through the whole routine of one spark plug at a time, no change. Rechecked every connection under the hood I could think of. Turns out the problem was electrical vs. mechanical.

As part of the engine swap I was to relocate the battery to the trunk, so the battery was sitting on a stool next to the car. The jumper cables I was using to try and start the car with just could not pull enough amps to even turn it over, much less start a new tight engine. It dawned on me late Saturday afternoon that this might be my problem, so I dug out some old 1 gauge welding cable I had. When I connected those she started up on the first turn of the key. After the meticulous work building and install the new engine, in the end it’s something obvious or stupid that will trip you up. Oh well stuff happens.

I’d like to thank everybody for the really great suggestions. I’ll post a link later today to a video we made at the moment of ignition. I won’t be posting all the videos we made of when it didn’t start, way to many of those…lol

Thanks again!
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
43,091
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Jan 15, 2012
#11
  • Jan 15, 2012
  • #11
Are you kidding me??? Really? You were trying to use jumper cables from a battery and you didn't think to mention that?


 
A

atv4fun

New Member
Jul 20, 2009
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Jan 15, 2012
#12
  • Jan 15, 2012
  • #12
Noobz347 said:
Are you kidding me??? Really? You were trying to use jumper cables from a battery and you didn't think to mention that?


Click to expand...
If I'd thought to mention it, it stands to reason that I would have then considered it a possible problem. Those jumper cables have always served we well over the years.
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
43,091
21,274
234
Box behind Walmart
Jan 15, 2012
#13
  • Jan 15, 2012
  • #13
atv4fun said:
If I'd thought to mention it, it stands to reason that I would have then considered it a possible problem. Those jumper cables have always served we well over the years.
Click to expand...












 
A

atv4fun

New Member
Jul 20, 2009
9
0
1
Feb 12, 2012
#14
  • Feb 12, 2012
  • #14
atv4fun said:
I went through the whole routine of one spark plug at a time, no change. Rechecked every connection under the hood I could think of. Turns out the problem was electrical vs. mechanical.

As part of the engine swap I was to relocate the battery to the trunk, so the battery was sitting on a stool next to the car. The jumper cables I was using to try and start the car with just could not pull enough amps to even turn it over, much less start a new tight engine. It dawned on me late Saturday afternoon that this might be my problem, so I dug out some old 1 gauge welding cable I had. When I connected those she started up on the first turn of the key. After the meticulous work building and install the new engine, in the end it’s something obvious or stupid that will trip you up. Oh well stuff happens.

I’d like to thank everybody for the really great suggestions. I’ll post a link later today to a video we made at the moment of ignition. I won’t be posting all the videos we made of when it didn’t start, way to many of those…lol

Thanks again!
Click to expand...

Video Link:
 

08GTCSTurbo

New Member
Jan 17, 2010
24
1
4
Rockford Illinois
Jan 16, 2013
#15
  • Jan 16, 2013
  • #15
your cams are probably 180 degrees off.
 
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