M988 6.2 liter running away idle

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Re: M988 6.2 liter running away idle

Post by Action » Wed Sep 12, 2018 9:39 am

I am trying to see what moves. The thing on left side moves, and the square brass thing , in the middle, hops to the other side of the pin with a spring on it. The most obvious result pf full throttle is that the IP moves closer to the camera.

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Re: M988 6.2 liter running away idle

Post by dilvoy » Wed Sep 12, 2018 12:59 pm

Fuel pressure within the well also has an effect on timing. High speed operation means more fuel used by the cylinders and less coming into the well from the injector return lines. Low speed operation and you get more fuel from the injector return lines and less advance. Must be something cracked or failed within the main portion of the injector pump. Fuel shut off is on the passenger side at the bottom of the well via a sliding shaft with a hole that allows for fuel flow when in the correct position. My guess is that it is time for another injector pump.
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Re: M988 6.2 liter running away idle

Post by Kurtshalftrack » Thu Sep 13, 2018 5:27 pm

Thank you gents. I am in the process of obtaining a take out IP. Is there anyway, to make sure it is an IP issue, prior to changing out the pump.? Could it be a bad injector or solenoid?
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Re: M988 6.2 liter running away idle

Post by Retired War Horses » Thu Sep 13, 2018 6:06 pm

Why even bother with a takeout...to much work getting in and out not to not go rebuilt
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Re: M988 6.2 liter running away idle

Post by Action » Thu Sep 13, 2018 7:21 pm

I thought he has a rebuilt unit in it. But he put the old top on it

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Re: M988 6.2 liter running away idle

Post by wooody1 » Thu Sep 13, 2018 8:21 pm

Each pump I believe is set up for each truck, you cannot just take a working pump from one then install into another, there will be slight differences, there us to be a guy in CA that rebuilt all these units day in day out

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Re: M988 6.2 liter running away idle

Post by Action » Fri Sep 14, 2018 5:03 am

wooody1 wrote:
Thu Sep 13, 2018 8:21 pm
Each pump I believe is set up for each truck, you cannot just take a working pump from one then install into another, there will be slight differences, there us to be a guy in CA that rebuilt all these units day in day out
????

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Re: M988 6.2 liter running away idle

Post by wooody1 » Fri Sep 14, 2018 5:07 am


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Re: M988 6.2 liter running away idle

Post by Action » Fri Sep 14, 2018 6:31 am

Maybe i am not seeing something...
The first link references, from Ford diesel page, how to increase fuel flow at the IP
The secend link is a 168 page manual.

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Re: M988 6.2 liter running away idle

Post by Retired War Horses » Fri Sep 14, 2018 7:13 am

wooody1 wrote:
Thu Sep 13, 2018 8:21 pm
Each pump I believe is set up for each truck, you cannot just take a working pump from one then install into another, there will be slight differences, there us to be a guy in CA that rebuilt all these units day in day out
many Pump models are interchangeable, I do it all the time...some are not, you just need to know WTF your doing.
And when in doubt, I call stanadyne and ask them.
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Re: M988 6.2 liter running away idle

Post by dilvoy » Fri Sep 14, 2018 7:26 am

Action wrote:
Fri Sep 14, 2018 5:03 am
wooody1 wrote:
Thu Sep 13, 2018 8:21 pm
Each pump I believe is set up for each truck, you cannot just take a working pump from one then install into another, there will be slight differences, there us to be a guy in CA that rebuilt all these units day in day out
????

You can't remove an injection pump from HMMWV Serial Number XXXXX1 and install it into HMMWV Serial Number XXXXX2. Isn't that obvious? :shock:
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Re: M988 6.2 liter running away idle

Post by wooody1 » Fri Sep 14, 2018 8:20 am

Yes that was my point, try it and see what happens

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Re: M988 6.2 liter running away idle

Post by dilvoy » Wed Sep 19, 2018 12:11 pm

How about removing the CDR Valve from the engine to make sure that it is not full of oil and feeding the cylinders?
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Re: M988 6.2 liter running away idle

Post by ohiohmmwv » Wed Sep 19, 2018 6:46 pm

Just buy my used engine(whole power pack even). It’s still running perfectly in my truck. Save you all the hassle. :)
I’ll even sell with the whole rolling chassis with excellent wheels/tires. I just need the body and hood.

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