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majordad's avatar
majordad
Explorer
Oct 20, 2018

Diesel pusher loses power going uphill

I have a 2001 Fleetwood Discovery 37 foot Diesel Pusher with 60,000 miles Last week we took a trip over Donner to Wheatland, Ca. And Bishops Pumpkin Farm.
Coming back, it ran great till we got into the mountains and started pulling hills and all of a sudden, I was down to 35 mph and had no power. We crawled up to the top of Donner Summit at 35 mph, when I got to the top, I stopped at the rest area and shutdown while using the facilities. After that it seemed to run better, but would still drop down in speed as soon as we encountered any kind of incline.
Does anyone have any ideas what to check? I am trying to avoid another generator situation, if it is something simple. Engine is a CAT.
THANKS IN ADVANCE.

MERRILL

9 Replies

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  • wolfe10's avatar
    wolfe10
    Explorer
    Oct 20, 2018
    Agree with the others.

    While it could be something else, the first step when power is limited under high fuel demand conditions is ALWAYS START BY CHANGING THE FUEL FILTERS.
  • naturist's avatar
    naturist
    Nomad
    Oct 20, 2018
    I don’t have a diesel pusher but I’ve had exactly those symptoms in two other turbo diesel vehicles and in both cases, marginally clogged fuel filters were the cause. They would flow enough fuel while cruising but when power demand rose to where lots of fuel was called for, they couldn’t pass enough and they would go into limp mode, 35 mph top speed and took a week to reach that. Shut off and restart, and back to normal until you needed full power.
  • YC_1's avatar
    YC_1
    Nomad
    Oct 20, 2018
    As suggested fuel filters and air filter but how much boost were you seeing?

    Any small leak in the plumbing for the turbo and the things will become slugs.
  • Diplomat_St_Poo's avatar
    Diplomat_St_Poo
    Explorer
    Oct 20, 2018
    We had almost the same issue going up the Siskiyou pass. Ours ran okay on the down hill. Lost power on the up hill. Limped to the CAT shop in Redding Ca. The codes said low fuel pressure. They replaced all the fuel filters. Took it for a test drive. Still no power.
    Changed the air filter. Poof. Back to full power.
  • SidecarFlip's avatar
    SidecarFlip
    Explorer III
    Oct 20, 2018
    Fuel filters first, then air cleaner, then the CAC boots and clamps. Sounds to me like a restricted fuel filter though.
  • Ava's avatar
    Ava
    Explorer
    Oct 20, 2018
    I ran into exactly the same problem last year. It was my fuel filter, the aftermarket Raycor mounted in the back. I did not have too many miles on them but perhaps some dirty diesel clogged it. Now I carry spares for both engine filters. Mine is a Cummins but shouldn’t be any different. As noted also check for any air intake leaks. Hope that is the cure.
  • Big_Katuna's avatar
    Big_Katuna
    Explorer II
    Oct 20, 2018
    No check engine light? If not, I would start with the basics; fuel filters, check air filter flow.

    Turbo gate not workin* correctly should throw a cod3 (I think).

    Now is the time for a Silverleaf diags system.
  • JCK's avatar
    JCK
    Explorer
    Oct 20, 2018
    I would have to guess your fuel filter is becoming plugged . My second suggestion is to check and possibly replace your air filter. Ether one of these could cause your power loss when pulling a hill .

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