RV Trip Planning Discussions

Go Back   iRV2 Forums > THE CHASSIS CLUB FORUMS > Ford Motorhome Chassis Forum
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
Thread Tools Search this Thread Display Modes
Old 02-25-2015, 11:26 PM   #1
Junior Member
Join Date: Feb 2015
Posts: 7
1998 National Tropi-Cal Fuel Issue

Hi there folks,

I'm trying to help my father out remotely, as he's 4000 miles away and not in the best health.

Here's a little background, the motorhome is a 1998 National Tropi-Cal with ford 460 fuel injected.

It sat for roughly 8 months and when he went to start it it would turn over but not start. here's whats been done and what we've found

Checked for spark at coil good spark, check for spark at plugs, it seemed a bit weak so he replaced distributor cap and rotor. as well as coil.

No difference.

Checked inertia switch it is in proper position.

Fuel pump could not be heard when ignition was turned to on.
Tank was dropped and pump replaced as well as inline filter.

Now fuel pump can be heard running for about 3 seconds when key is turned, but no pressure at schrader valve on fuel rail no fuel no air or anything.

Here's my questions, first off what dictates the run time of the fuel pump?
Is there a pressure sensor that could be messed up.
is there a hidden inline booster pump that he may not have noticed on these models.
Any thoughts of what the issue could be.
The engine will fire with starter fluid into the intake. it just doesnt seem to be getting fuel.

Is there an easy way I can tell him to bypass fuel pump control and run it manually?.

Thanks in advance

wmacdonald is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 02-25-2015, 11:56 PM   #2
Senior Member
Ford Super Duty Owner
Join Date: Oct 2010
Location: Cold Spring , Minnesota
Posts: 256
If it is a 7.5L 460 V8 engine it is probably a 1997 chassis. With the schrader valve pin depressed open, try cycling the fuel pump a few times by turning the key on for three seconds until the pump stops and turn the key off and back on a few times to push fuel up through the depressed pin on the schrader valve.

The computer stops the fuel pump if the engine isn't running when the ignition switch is released from start to the on position.

1995 F53 35U Bounder, Wide Body-Large Vertical Windows-NO SLIDES, Front Axle-Davis Tru-Trac Bar, Rear Axle-SuperSteer Trac Bar, TowBar/Brake System-NSA ReadyBrute Elite, Family Motor Coach Association F 513--F 513s
Dwight is offline   Reply With Quote
Old 02-26-2015, 12:45 AM   #3
Junior Member
Join Date: Feb 2015
Posts: 7

I had him try this already, probably 25 cycles. no luck.
Thanks for the suggestion
wmacdonald is offline   Reply With Quote
Old 02-26-2015, 06:27 AM   #4
Senior Member
subford's Avatar
Ford Super Duty Owner
Join Date: Dec 2009
Location: Easton, Ks
Posts: 2,517
You did not say if this is an "E" series or a F53 Ford so I will guess it is a 1997 F53.
The PCM Computer has a one second timer for the fuel system. There is no fuel pressure sensor or inline fuel pump.
When the key is turned to the run position the Computer will ground the fuel pump relay for one second and then let the fuel pump relay open to shut off the fuel pump.
But if the engine is cranking or running the PCM Computer will get a PIP from the distributor and each time it sees a PIP pulse it will run the fuel pumps for another second. The PIP pulse will come faster than one second while cranking or if the engine is running. So the fuel pump will run all the time the engine is cranking or running.

To bypass the computer and run the fuel pump all the time the key is on you would ground pin #6 of the self-test plug or short it to pin #2 of the self-test plug.

I just ran into the same problem a few days ago as you have and the installer reversed the power wires to the pump and the pump was running backwards. On his the stock ground wire to the pump was a orange wire and he took it as the power wire and the brown power wire looked black so he thought it was the ground wire.
Note the above wire colors are not the wire colors on the 1997 F53.

The self-test plugs location:

Note that most of the information above does not apply if it is built on an E-series chassis.
1995 COACHMEN Santara 350FL on a 1994 Ford F53
subford is offline   Reply With Quote
Old 02-26-2015, 03:43 PM   #5
Senior Member
chboone's Avatar

National RV Owners Club
Ford Super Duty Owner
Join Date: Sep 2010
Location: Horse Town USA, CA.
Posts: 3,236
It is an F53. Not the OP, just responding for him.
1999 35 ft. Dolphin 5350, F53, Banks System, 5 Stars Tune, Air Lift Air Bags, Koni Shocks, Blue OX TruCenter, TigerTrak track bars F&R, Roadmaster 1-3/4" rear auxiliary sway bar, 2004 F450 Lariat 6.0 Diesel Crew Cab DRW, 4X4, B&W Custom Truck Bed, GVWR 15,000, Front GAWR 6,000, Rear GAWR 11,000, GCWR 26,000, 1994 36ft Avion 5er, GVWR 13,700
chboone is offline   Reply With Quote

fuel, national

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
1991 Fleetwood 460 Ford fuel pump/starting problems Dick & Kathy Ford Motorhome Chassis Forum 7 10-05-2014 11:45 AM
Crazy Fuel Stop Experiences Musikboy Class A Motorhome Discussions 38 08-04-2014 06:04 PM
Fuel Gauge, Sender, Empty Fuel Tank TwelveVolt Spartan Motorhome Chassis Forum 2 07-06-2014 11:54 AM
Anybody pulled the fuel rail and injectors on 8.1L? deputydog Workhorse and Chevrolet Chassis Motorhome Forum 14 01-15-2014 06:33 PM
National Rally Attendees 2000-2010 Madame Boomer Rally Master's Forum 0 08-13-2010 05:41 AM

» Featured Campgrounds

Reviews provided by

Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 08:43 PM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.