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Nose dive with brakes..engine cuts out

72Burro

Jr. Member
Joined
Jan 5, 2004
Messages
51
Loc.
Ca
Finally got my hydroboost installed and it's wonderful to be able to stop like a new car.. ;D
I took it out this evening for a test run and try some more panic stops. Both times I panic stopped the nose dives down hard and the engine cut both times. :eek: Any ideas on why the engine is cutting out? You I can see this could be danagerous if the engine is cutting and losing steering power.. Thanks
 
OP
OP
7

72Burro

Jr. Member
Joined
Jan 5, 2004
Messages
51
Loc.
Ca
idle speed was 600rpm, i bumped it a bit and I ran it again and the engine died the first time i slammed on the brakes..
With the hood open, i did notice that when i hit the brakes hard the PS belt jumps up a few inches before the pulley, not sure if that's normal for hydroboost or if that could be the cause. I jiggled all the electrical connections with it running to see if that could be it, but nothing..
 

griff

Sr. Member
Joined
Nov 30, 2002
Messages
598
Loc.
solvang, ca
maybe your float is too high and it is causing gas too spill down the intake when you brake hard.
 

SaddleUp

Bronco Guru
Joined
May 23, 2004
Messages
9,655
Loc.
Vancouver, WA
It could also be a bad connection doing it. I few years back I had a loose connection on my starter realy that acted like that. It took me a few days to figure out why it would just up and die and then as soon as I slowed down to stop it would fire back up again.
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,835
My guess would be bad connector in the wiring or fuel sloshing around in the bowl.

If you are brave and careful, you could try removing the belt and driving the truck (without touching the brake pedal) and see if you can reproduce the problem. I doubt that you find the pump pulling the motor down that much.
 

racebronco

Sr. Member
Joined
Oct 10, 2005
Messages
529
Loc.
Jeffersonville, IN
try tightening your power steering belt... it shouldn't be moving that much.. what year bronco?? did it come with factory powers steeing?? how was your hard stops before, did it dive as much as it does now??
 
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7

72Burro

Jr. Member
Joined
Jan 5, 2004
Messages
51
Loc.
Ca
I'll go back and check the fuel level and the electrical connections again. Thinking about it more, this happened a few years back in the snow; when i'd rev the motor to get over snow drifts the truck would bounce and the engine would die.

It's a 72, i put the 4x4x2 PS and saginaw pump on it about 3yrs ago, just added the hydroboost a few weeks ago. Thanks
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,835
72Burro said:
I'll go back and check the fuel level and the electrical connections again. Thinking about it more, this happened a few years back in the snow; when i'd rev the motor to get over snow drifts the truck would bounce and the engine would die.

It's a 72, i put the 4x4x2 PS and saginaw pump on it about 3yrs ago, just added the hydroboost a few weeks ago. Thanks

With that, my guess is a carb issue. Back to that vicious cycle of fixing one problem to uncover another.
 

daddyg

Bronco Parts Collector
Joined
Dec 30, 2004
Messages
2,114
Loc.
Toney,AL
I also agree it's a carb issue. Sounds like fuel is being sloshed out of the vent and down the barrel of the carb thus drowning out the engine. Been there done that.
 
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72Burro

Jr. Member
Joined
Jan 5, 2004
Messages
51
Loc.
Ca
I checked the floats, fuel from the secondary bowl drained out of the sight window when i opened it, i'm pretty sure that had to be the problem.. thanks for pointing me in the right direction..
 
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