B&M megashifter intermittent no start
#1
Junior Member
Thread Starter
Join Date: May 2013
Location: Worcester, MA
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
Engine: sbc 355, Lunati cam (lost cam card)
Transmission: Stock 700r4
Axle/Gears: 3.73 posi
B&M megashifter intermittent no start
Installed a mega shifter about month ago, worked flawlessly for 2.5 weeks went to start no start then after a couple expletives it started worked for another day then wouldn't start at all. Checked everything for the shifter after putting the two wires together for the neutral safety switch it started fine. Figure it's the safety switch took and switched the 2 switches again would start right up with new switch installed only lasted 2 days. My question is has anyone experienced both switches going bad or any suggestions?
#2
Supreme Member
iTrader: (13)
Join Date: Dec 2002
Location: Bowdon, GA.
Posts: 2,535
Likes: 0
Received 16 Likes
on
14 Posts
Car: 1988 Camaro
Engine: 355, 10.34:1, 249/252 @.050", IK200
Transmission: TH-400, 3500 stall 9.5" converter
Axle/Gears: Ford 9", detroit locker, 3.89 gears
Re: B&M megashifter intermittent no start
My micro switches from when I bought the shifter 17 years ago are both still working perfect.
Make sure the switches are bad before tossing or replacing. Use a volt/ohm meter to check them.
The little lever arms can bend and not touch the little bumps on side of shift gate plate. Also the switch mounting is adjustable.
Not sure if they have changed the shifter design in the last 17 years or not but mine was setup where you put the NSS and back up light switches on top of each other, put 2 long skinny bolts through the 2 switches and through the mounting spot on shifter. The switches then can be moved around some due to holes being oversized so you can adjust as needed. If your screws are not tight enough or if your alittle out of adjustment the switch arm will not hit the bumps on the plate enough to trip the switches action.
Make sure the switches are bad before tossing or replacing. Use a volt/ohm meter to check them.
The little lever arms can bend and not touch the little bumps on side of shift gate plate. Also the switch mounting is adjustable.
Not sure if they have changed the shifter design in the last 17 years or not but mine was setup where you put the NSS and back up light switches on top of each other, put 2 long skinny bolts through the 2 switches and through the mounting spot on shifter. The switches then can be moved around some due to holes being oversized so you can adjust as needed. If your screws are not tight enough or if your alittle out of adjustment the switch arm will not hit the bumps on the plate enough to trip the switches action.
#3
Member
iTrader: (1)
Join Date: Dec 2012
Posts: 124
Likes: 0
Received 3 Likes
on
2 Posts
Car: 91 RS
Engine: 4 bolt 350, .060 over
Transmission: 700R-4
Axle/Gears: 3.23
Re: B&M megashifter intermittent no start
May not be the shifter and just coincidental the problem is happening now. I had that intermittent start prob on my '91 awhile back. The starter enable relay was going bad and it drove me nuts, same thing you describe, mess with something electrical and it starts, I was trouble shooting through the starter and its wires etc.
The relay is located behind the kick panel by your left foot
The relay is located behind the kick panel by your left foot
#4
Supreme Member
iTrader: (4)
Join Date: Sep 2004
Location: MN
Posts: 2,069
Likes: 0
Received 3 Likes
on
3 Posts
Car: 85 SC, 86 Berlinetta
Engine: V6, V8
Transmission: 700r4, 700r4
Re: B&M megashifter intermittent no start
With intermittent problems like this you sometimes have to wait for it to fail and then use a multi-meter to find the problem. So bring one with when you drive it around.
Thread
Thread Starter
Forum
Replies
Last Post
92camaroJoe
Tech / General Engine
6
08-13-2015 06:07 AM