Questions on M816 Summer project

[jmcguffin]

Just picked up a summer project of an M816 to work on and found this old thread that seems to apply to part of what's in front of me ( http://www.steelsoldiers.com/index.php?name=PNphpBB2&file=viewtopic&t=13054) Going through the fuel system now and replacing the old hoses and rebuilding the selector valve. I suspect may need to send the pump off for a freshen up. Truck is idling like a champ when it warms up, but it goes to the governer limited rpm of 2100 and is very slow to fall back to idle when you take your foot off of the pedal. Other interesting note is that when you are in neutral and pull the throttle lock in the dash back just two detents, the governer takes it all the way to 2100 rpm. Still have lots of rotation left in the throttle lever on the side of the pump. I'm new to a governed Cummins but it just doesn't seem to be what I would suspect.

Cabell, can I ask you who you used in the area to rebuild your pump and what their prices were like ?

Next question is about the temparture gauge in the dash. Is it the same unit as a deuce or is is specific to the 8xx series. I'm chasing the wiring with a meter this weekend.

Ther will be winch questions in the future, looks like someone wond the front one up like a clock spring and bent some of the cable guidance system.

Thanks for your help.

Cheers,

Jim McGuffin

 

[goldneagle]

 

[beaubeau]

fuel pump

Just my 2 Cents! Before even thingking about fuel pump work be sure all fuel lines are good, no cracks. I had trouble with the tank change switch{selector valve!!??}, so I disconnected the main line to IP, and ran direct to lLeft tank. both feed line and return line. this simplifies things until U get it running good . U can make changes later. Be sure the fuel is clean and run fuel conditioner and or trans. oil, and Mystery oil. It cleans fuel systems well. This is much cheaper than a pump. Be sure to check screen on top of PI . This is the Large screw on top. Take it out and clean it good. Good luck, Phil

 

[AMGeneral]

Speaking from expierence here( I had a 1973 M816 as my last wrecker) replace ALL the rubber fuel suction lines from the tanks to the injection pump BEFORE having the pump rebuilt(it will run you about $400 for a complete pump rebuild) if this does not cure your idle down problem then think about rebuilding the pump and /or replacing the tank selector valve.

As far as the hand throttle response,that is the proper way for the cab hand throttle to work,the PT pump is VERY touchy as far as the throttle goes.
Also,be sure it has the CORRECT injection pump for the wrecker(it will have an auxiliary governer above and to the rear of the pump with another throttle cable going back to the wrecker body for throttle control while operating the crane. Hope this helps!!

 

[jmcguffin]

Thanks All!


I got out with the camera this morning to take a few pictures.

AMGeneral,

Does this look like what you remember having on yours ? The line into the pump from the filter is new ( along with a new filter element). It made a huge difference for first start of the day and stabilized the idle. The cable from the rear throttle control is hooked up, but it seems to be frozen. Tried a motorcycle cable luber on it but it isn't moving yet. I'm going to pull it off this weekend and start soaking it to see if it will loosen up.

 

[jmcguffin]

Just a couple of more pictures of the winch wind-up. Fixing this will be later this summer. The bend is pretty obvious. The engagement/dissengagement lever on the winch housing seems to be stuck in place engaged and there is a gear oil leak coming from the driver' side where the main spool goes into the housing.

 

[73m819]

that ip is the one i have on the 819, it is the wrong one for the 816, it should have a mvs ip, it will have about a 9" tail up off the upper rear, this will have the air actuator to set the rpm at 1800 for the crane operation as well the remote throttle arm for when you are using the rear winch
im getting ready to install a mvs ip on the 819 so i can set the operating rpm for the crane without dinking with the hand throttle

 

[AMGeneral]

I second Ron's comment,that is the incorrect injection pump for a M816

 

[Crash_AF]

Does this look like what you remember having on yours ? The line into the pump from the filter is new ( along with a new filter element). It made a huge difference for first start of the day and stabilized the idle.

I've attached some pics of my 816's pump, I think it's the right one. My hand throttle is the same way, three clicks and it's against the governor.

The cable from the rear throttle control is hooked up, but it seems to be frozen. Tried a motorcycle cable luber on it but it isn't moving yet. I'm going to pull it off this weekend and start soaking it to see if it will loosen up.

Mine is stuck too, so if you figure out a good way to loosen it up, please pass it along.

Later,
Joe

 

[73m819]

thats the right one.

 

[Gamagoat1]

Crash,
You have the correct IP.
The rear throttle is a bear, it's just a steel spring 20 some feet long with a steel wire going thru it. Can you spell RUST. I tried to repair mine and ended up throwing it away. Got a new one from Saturn, but didn't use it it was somewhat different.
I've started using Areo Kroil on stuff with amazing results. Makes WD-40 and PB Blaster work as well as water.
Joe, what kind of milage did you get coming up here for the parade??

 

[Crash_AF]

Yea, I figured it was right.

On the mileage, I don't know. The speedo adapter broke just outside of Aurora so I don't have a mileage estimate.

I do know that I drove from Co Springs to Commerce City and back, and went from Co Springs to Elizabeth to pick up a deuce and back with it in tow and didn't run out of fuel... LOL I'm pretty sure the right tank is empty now though.

Later,
Joe

 

[73m819]

GG,and CAF that is the WRONG ip, does not have the rear air piston and the remote throttle, the correct ip is a mvs pump. look in tm 206-34-1 , fuel group, section 5-21, pages 5-55, to 5-57, this gives the layout of the mvs ip, rear section that has the air cylinder and the remote throttle arm, in fact the fuel groug has a lot of " EXECPT of 816 and 819"

 

[Crash_AF]

GG,and CAF that is the WRONG ip, does not have the rear air piston and the remote throttle,

Yes it does... (at least mine does) the air cylinder is the small silver cylinder with red lettering that is in the upper right corner of the second picture. If you look at Jim's first post, that IP is the AFC pump and mine is the VS pump.

Later,
Joe

 

[73m819]

afc, YOU are right, i was looking at the upper green ip all this time, maya copa, maya copa, maya copa, all i can say must have been a major senior moment

 

[jmcguffin]

Thanks for all of the expertise! I've gone back to looking at the TMs and now the diagrams there make much more sense.

It seems like having the wrong pump on an m816 has been seen before. If I'm grasping whats going on with what I have here, it looks like I have engine speeds for running the rear power splitter of just above idle or the 2100 rpm that the normal engine governor kicks in at, with very little control in the middle. I'm not planning on working the rear winch or boom anywhere near their capacity anytime soon, so just above idle may have to do for a while. Where does one normally begin the search for a reaonably priced correct pump for an M816 ( John Winslow ) ?

Looking at the TMs and Crash_AFs picture does the governor and air cylinder just bolt onto a PT pump base assembly, or is that just simplifying it too much ? Does it all have to be calibrated together ?

Cheers,

Jim McGuffin

 

[73m819]

a different pump

 

[DaveP]

heres my M819 pump. hope this helps.

 

[Crash_AF]

The rear throttle is a bear, it's just a steel spring 20 some feet long with a steel wire going thru it. Can you spell RUST. I tried to repair mine and ended up throwing it away. Got a new one from Saturn.

I just called Saturn and they do not have the cable listed in the TM... do you have a different part number I could try with them or another source?

Thanks,
Joe

 

[Gamagoat1]

Joe,
The one they sent me was not original. Its larger in diameter and sealed, with larger connections on each end.
Instead of jacking around trying to make the newer one fit, I used one from a M543. It's the same bot a little shorter.