Motorhome engine starting Issues

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Discussion Overview

The discussion revolves around starting issues with a 1979 Dodge Fireball D450 motorhome. Participants explore potential causes for the engine not starting despite various components being replaced, including the starter and ignition system. The conversation includes troubleshooting steps and considerations regarding fuel, spark, air, and mechanical factors.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant describes the extensive replacement of components without resolving the starting issue, raising the possibility of a sensor or fuse being affected by a recent gear shifter repair.
  • Another participant asks for clarification on what "it won't start" means, suggesting that the problem could be related to whether the engine cranks, attempts to fire, or does not crank at all.
  • A suggestion is made to consider potential reassembly errors during the repairs.
  • Participants propose a systematic approach to troubleshooting, emphasizing the need for spark, air, fuel, and timing, and listing specific checks for each category, such as verifying fuel solenoid operation and checking for compression.
  • One participant mentions that the motorhome likely does not have a safety switch that disables ignition based on gear shifter position, but suggests testing the spark plugs while cranking.
  • Another participant confirms that a neutral safety switch would prevent cranking but not disable ignition, indicating a concern for battery drainage if such a switch were in place.

Areas of Agreement / Disagreement

Participants express differing views on the role of the gear shifter repair and the presence of safety switches. While some agree on the need for systematic troubleshooting, there is no consensus on the exact cause of the starting issue.

Contextual Notes

Participants have not resolved the underlying assumptions regarding the ignition system and safety features, and the discussion remains open to various interpretations of the symptoms described.

JimmyThe9
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TL;DR
My 1979 Dodge Fireball D450 5.9l Motorhome. It has recently stopped running after having a starter issue.
My 1979 Dodge Fireball D450 5.9l Motorhome. It has recently stopped running after having a starter issue. I replaced the starter, starter relay, starter solenoid, spark plugs, distributor and router, battery, and cables, and it still won't start. The fuel pump and filter are good. Also, I have replaced the pin that holds the gear shifter on the steering column in place could that have set off a sensor or burned a fuse in the ignition?
 
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Welcome to PF.

What do you mean by "it won't start"? Does it crank and not fire? Does it crank and try to fire but won't run steady? Does it not crank at all (no starter solenoid "click")? What does the battery voltage read when you try to start the engine (before, during cranking, after)?
 
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Likes   Reactions: Lnewqban, DeBangis21 and Vanadium 50
In a case like this the first thing to do is ask yourself what you could have reassembled wrong.
 
Partition the problem.
It needs a spark, air, fuel and a sense of timing.

Starter motor.
Does the engine turn at normal speed, and in the right direction?

Fuel.
Does the fuel cut solenoid operate?
Is there an engine immobiliser?
Is the fuel tank and pump full of water?
How long was it sitting. Is the fuel old and stale?
Are plugs dry, or wet with unburned fuel?
If you spray an ether-based engine-starting-fluid into the air inlet, does it fire and run momentarily?

Spark.
Does the coil spark, and the spark get to the distributor?
Does the spark get from the distributor to the spark plug?

Air.
Is the air filter completely blocked or soaked in oil?

Mechanical.
Does the engine have compression?
Has the timing belt or chain failed?
 
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Likes   Reactions: Vanadium 50, Lnewqban and berkeman
Welcome, Jimmy!

I believe that truck does not have any safety switch killing the ignition based on the position of the gear shifter on the steering column, but just in case, you could easily test how alive one of the eight spark plugs is while cranking.

https://www.harborfreight.com/in-li...SW86CCqe_Urin2Vq0TM2mobs_paa2EQxoCtNAQAvD_BwE
63590_W3.jpg
 
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Likes   Reactions: berkeman
Neutral safety switch will prevent the starter from cranking. No sense to allow cranking while disabling the ignition. Some unsuspecting person would run the battery down attempting to start if that were the case.
 
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