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casualrver's avatar
casualrver
Explorer
Jun 01, 2014

Chevy 454 Problems PLEASE HELP!!!

Sorry if there is a thread for this but I could not find one that really helped me out.

Here is the problem I am having:

I have a 1986 pace arrow. It has a new rebuilt Chevy 454 in it (rebuilt last year). The motor home will start just fine, but after about a 1/4 mile down the road it will die. We thought it might have been the fuel filters so we replaced both of them. Then we thought it might have been the inline fuel pump but that checked out ok. So we looked at the distributor and ignition module. The ignition module had some burn marks around the outside of magnet so we replaced it. Starts right up with no problem. We took it out on a test drive and it died about 1/4 mile down the road again. After it dies we can't get it back started again and the starter acts like it is really working hard to turn the motor.

I have been trying to wrap my head around this problem and can't get this thing figured out. I would really appreciate some help.

I am thinking maybe a clogged catalytic converter? What do you guys think?

Thanks in advance for the help!!!
Class A
  • ScottG's avatar
    ScottG
    Nomad
    Jun 01, 2014
    Suburbans of that era would loose both the fuel pump and its relay and cause the starvation symptoms you have. Might be cheap insurance to replace the relay now.
  • Born_To_Travel's avatar
    Born_To_Travel
    Explorer
    Jun 01, 2014
    Remove the starter and have it load tested at an auto parts store.. Chevys for years have had a problem with engine heat on the starter motor/solenoid and when they go bad you will have a problem as you describe... If it turns over hard after it happens, But starts fine after a half hour or so, I would pull it off and have it checked...
  • Executive45's avatar
    Executive45
    Explorer III
    Jun 01, 2014
    It's an 86 so no crankshaft sensor.

    From your description it sounds like you are having a fuel starvation issue. The coach starts up and runs when it's cold but stalls after it warms up. Several things come to mind.

    First is routing of your fuel lines. Make sure they're no where near your exhaust manifolds or any heat source. Wrap them if necessary.
    Second..are you using rubber fuel lines or steel? Rubber will collapse under hard throttle in certain circumstances.
    Third..are you using an electric or manual fuel pump?
    Fourth..after it stalls, remove the air cleaner (if its on) and check the butterflies in the carb. Often, after the engine warms up, the spring that holds the butterflies in place is weak and the butterflies will close under throttle. This provides too rich a mixture and will cause the motor to stall. An easy test is to warm the engine, then wire the butterflies open and drive it. See if it stalls. If not, your problem is in the carb.

    I don't see it being an exhaust issue as you would experience that without driving the coach.

    Try to eliminate the fuel delivery problem. Once that's proven not to be the issue, let us know and we can try some electrical things. My guess is one of the above will be the culprit....with the carb my number one guess....Dennis
  • Coyote74's avatar
    Coyote74
    Explorer
    Jun 01, 2014
    Sounds like in tank fuel pump.can you look down the carb with the breather off when it quits to see if you have fuel spray when you pump the linkage. My 87 had 2 pumps , 1 on block and 1 in tank.
  • Horsedoc's avatar
    Horsedoc
    Explorer II
    Jun 01, 2014
    Are you sure the gas line is not collapsing as the demand for gas increases as you accelerate?
  • dadechil's avatar
    dadechil
    Explorer
    Jun 01, 2014
    To test clogged exhaust remove your O2 sensors and drive ( not far this is only for testing) If it makes it past your normal stall point it would be a good guess that the exhaust is clogged.

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