Is my m998 motor toast?

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Re: Is my m998 motor toast?

Post by Action » Wed May 09, 2018 6:50 pm

The cable with the accordion looking boot is the end of the throttle cable. Near where it attaches should be the thick spring. Is it there? Maybe 1/2" wide and 2" long? It may look like 2 springs stuck inside each other.

Image

Image

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Re: Is my m998 motor toast?

Post by Action » Wed May 09, 2018 6:51 pm

Did you actually turn the motor? Or just the fan?

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Re: Is my m998 motor toast?

Post by Kurtshalftrack » Thu May 10, 2018 1:56 am

I will look for the spring this evening when I get home from work. The picture above is exactly wha it was talking about being detached....would that cause the idle to run away? . I just turned the fan...I thought the meant the motor was turning also ...No? I can put a breaker bar on it this evening and actually turn the nut on the motor.
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Re: Is my m998 motor toast?

Post by Action » Thu May 10, 2018 3:58 am

The cable applies throttle. The spring brings it back to idle.

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Re: Is my m998 motor toast?

Post by Ted Gates » Thu May 10, 2018 4:46 am

Turning the fan does not necessarily mean that the crank is turning. Turn the crank several times around with breaker bar and socket to get oil on journals prior to starting when pan is back on and full of oil. It is a non turbo, so run away engine is typically throttle related. Best way to stop it is to turn off ignition switch and suffocate it with a 2x6 on intake (after filter housing in front of air intake horn) and or vise grips/pliers on supply fuel line to injection pump after fuel filter (I've done this before and it works). To reconnect throttle cable to IP stud, you will need the little clip. The clip may be in the engine valley so take a magnet and from back of engine, search for clip under IP. Else, buy a new one. Replace the throttle return springs, typically 2 springs woven together.

If engine runs normally but does not shut off once you start it, then you could now have a problem(s) with the IP. Either the solenoid does not turn off fuel (top end of IP and is easily replaced) or the internally the IP is leaking. Best to buy a new/rebuilt IP and swap it out. Takes about 4 hours and you can do it in place.

If you need pictures, let us know.

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Re: Is my m998 motor toast?

Post by Kurtshalftrack » Fri May 11, 2018 12:41 am

Fantastic information ! Thank you so much. The spring returning the throddle cable to position is there...but is bent an and out of shape...i wonder if this caused the issue. Where is the best place to buy a new spring and clip for the throttle cable assembly? Again, thank you so much for the help.
Kurt
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1984 M998
M100
America is still the greatest country on earth...don't give up the fight!


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Re: Is my m998 motor toast?

Post by Ted Gates » Fri May 11, 2018 3:17 am

Kurt,
Kascar, www.real4wd.com is a good source with inventory for such items.
I bet engine is good. Rings are now seated :D
Ted

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Re: Is my m998 motor toast?

Post by Kurtshalftrack » Sat May 12, 2018 2:16 am

Good news! I was able to but a breaker bar on the motor and turn it! So that’s a good sign. Replacing battery cables and throttle return spring and then I will attempt to fire it up! Well keep you all posted! Ted...seated springs.. :D
Kurt
1943 M3 Halftrack
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1984 M998
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America is still the greatest country on earth...don't give up the fight!


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Re: Is my m998 motor toast?

Post by Raklatif » Sun May 20, 2018 9:38 am

I would suggest at this point to install a manual fuel cutoff switch. Hook it up right before the fuel filter. just incase you have another case of runaway diesel.

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alt belts x2 ...any ideas

Post by Kurtshalftrack » Sat Sep 08, 2018 3:39 am

misfire on this one sorry....thank you all! Great advice! I owe you a beer when you come to VA look me up.
Last edited by Kurtshalftrack on Sat Sep 08, 2018 3:53 pm, edited 1 time in total.
Kurt
1943 M3 Halftrack
1952 M37
1984 M998
M100
America is still the greatest country on earth...don't give up the fight!


San Diego, CA

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altenator belts problem

Post by Kurtshalftrack » Sat Sep 08, 2018 3:44 am

Ok, it been a while. Finally have time to do some wrenching again. Attempting to place the alternator blets back on my m998 5.2 l motor. I have the Original 60 amp alt.with two belts ( 4 belts total for the system). I have lossend the alternator and moved it to the closet position...belts still will not go over the pulley. Went under and moved the other idle pulley wheel as far as it would go...still no luck with the belts....any ideas on how to get them on the alt pulley? Thanks.
Kurt
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1943 M3 Halftrack
1952 M37
1984 M998
M100
America is still the greatest country on earth...don't give up the fight!


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Ted Gates
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Re: Is my m998 motor toast?

Post by Ted Gates » Sat Sep 08, 2018 11:54 am

Wrong belts Kurt?

If not, then loosen generator bolts to get an angle on pulley and rotate pulley as you slide belt over. PIA but it should work.

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Re: Is my m998 motor toast?

Post by Kurtshalftrack » Sat Sep 08, 2018 3:39 pm

Ted worked like a charm....though not sure it was so good for the belts. Thank you!
Kurt
1943 M3 Halftrack
1952 M37
1984 M998
M100
America is still the greatest country on earth...don't give up the fight!


San Diego, CA

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Re: Is my m998 motor toast?

Post by wooody1 » Sun Sep 09, 2018 7:28 am

Have you got a hand throttle cable installed on your engine as well, maybe that is the issue, I don't know much about them but maybe the cable is snagged, cannot be much to it!!

I have asked the other person to send me the link re IP timing and how is should be set, other say is maybe the cold advance on top of the IP, however not sure of your exact set up

Kurtshalftrack
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Re: Is my m998 motor toast?

Post by Kurtshalftrack » Sun Sep 09, 2018 10:22 am

I do have a hand throttle cable, which I disconnected...I am going to take a look at the IP. Thank you.
Kurt
1943 M3 Halftrack
1952 M37
1984 M998
M100
America is still the greatest country on earth...don't give up the fight!


San Diego, CA


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