Cold Start = FULL THROTTLE IDLE??? (New Injection Pump Just Installed)

[MuddWeiser]

I'm trying to figure out how the Cold Advance "doo hicky" works on the Injection Pump...

Just had my Injection Pump rebuilt (I went with O-F-I out of Eugene Oregon).

After installing the Injection Pump, I plugged my block heater in to help warm up the motor and oil so that when I cranked it over and over to bleed the air out - it might turn easier.

Motor fired up and sounded GREAT.


Fast Forward one day, early morning, It's 27 degrees (f) outside. I cycle the new glowplugs 2 times. Then, According to the sun visor instruction sheet it says depress accellerator ALL THE WAY when cranking if below 32 degrees (f). So I depress accellerator all the way down, and crank to fire the motor. Motor fires right up and I let off accellerator and the engine is at FULL THROTTLE. I freak out and shut engine off. All of this happened in 2 - 3 seconds...

I then waited 30 seconds and then WITHOUT the accellerator, I just crank motor and it fires right up and idles normal for 5 minutes in park to warm up UNTIL I decide to start driving.

AS SOON AS I GAVE IT GAS. I gave it enough gas to go up the short driveway and when I reached the top I backed off the accellerator but the truck kept going, I shifted to neutral and the motor went straight to FULL THROTTLE - I shut it off immediatley.

Turned it right back on and it was back to idle speed and didn't do this weird behavior again for the entire day (engine was warm rest of day).

Fast Forward AGAIN to this a.m. 37 degrees (f). Half Throttle when starting and it fired right up but again went to full throttle. I turned it off and took the smaller car.


WHATS UP HERE? It is NOT a stuck accellerator cable, it ONLY happens when the motor is "cold"? I can't figure this out.

HOW DOES THE COLD ADVANCE WORK? It is a long screw in a solenoid. I am wondering if when I apply full or half throttle then click to start, the solenoid LOCKS the screw in that position until the SOLENOID gets warm and turns off???

I can't figure it out. Any pointers or tips as to where I should be looking and what I should be looking for?

 

[Westech]

sounds like your pump is crap. I would contact the rebuilder and get another one.

How the cold start works is it advances the timing 10* and there is a solanoide that pushs on the leaver to bump the idle to 800-900 RPM. After it warms up a bit the solanoide switches off and the 700-750 RPM idle is restored.

 

[MuleMac01]

take it back have em fix it sorry to say

 

[WARWAG]

Sounds dangerous!

 

[Djfreema]

Try backing out the rod that goes through the cold start sylenoid. It is adjustable and takes 30 seconds, I had to adjust mine after replacing the injector pump. Its probably not wide open throttle but pushing down enough without a load it seems like wide open throttle.

 

[motormayhem]

It is called a housing pressure cold advance solenoid.

This article talks about it.
Motor Mayhem Blog Archive Stanadyne DB2 Fuel Injection Pump

 

[Wolf.Dose]

With the propper engine oil not used over 5000 miles you do not need the cold idle up selenoid. In the injection pump the cold advance is the contact on top of the pump with the same harness as the selenoid. This increases the inside pressure by some 3 PSI to actuate the rotation of the timing ring (This is the big thing on the underside of the pump where a pressurized piston is located.). It advances injection timing ring by some three degrees to earlier injection.
Considering your glow plugs and the electronics for that are in propper shape, you do not need that stuff in the pump. The engine will start anyway with a good starter, means some 200 rpm starting cranks. If below, the engine will not start.
The cold advance stuff is not needed , even at -22°Celsius, which is some -10 F.
And forget the full throttle when starting, more than half is not required, if the system is in propper shape. Normally low idle is sufficiant.
I know what I'm talking about after 14 years with a M1009 (372,000 km or 232,500 miles) and over 500 engine hours with a 6.2 l Diesel in my M715 since 2004. My cold advance system in the M715 does not work due to a failure in the swich in the block. Replacement is not difficult; however the coulant will run out of the engine and I do not miss the cold advance.
Wolf

 

[rizzo]

Mine will high idle. I usually let it warm up all the way or turn it off then start it again to reset the high idle.

I would adjust the screw on the solenoid

 

[Mshawnm209r]

Mine will high idle. I usually let it warm up all the way or turn it off then start it again to reset the high idle.

I would adjust the screw on the solenoid

what is the proper way to adjust the screw on top of the solenoid? I need to know this

 

[dougco1]

You most likely have a bad cold advance solenoid. Unplug it and see if you still have revving issues. I had the same issue with mine and I replaced the solenoid and never looked back.

 

[Mshawnm209r]

Can someone tell the prpper procedure for setting the cold start advance or the high idle?

 

[dougco1]

I start mine this way;

When starting a cold engine you turn the key to on, depress the fuel pedal fully then release to about half pedal. Wait for the glow plug light and then start it. If the high idle solenoid is working properly and the engine temp sensor is functioning, it will be set to high idle. As the engine warms up, the temp sensor will drop power to the solenoid and your truck will drop to normal idle "normally in a few minutes".

Several factors can change things and all equipment must be in working order to operate as designed. I had a bad engine temp sensor so the system thought it was a cold engine all the time and sending constant power to the solenoid.

I replaced the sensor with a new one and then I found that the old solenoid had a mind of its own. The solenoide "when powered" is designed to be only strong enough to hold the throttle open when you set it by depressing the pedal. But its not designed strong enough to set it to high idle by itself . So I replaced that with a new one and it now starts and works as it should.

34 year old parts do fail so you can expect to be replacing parts from time to time. That's what I love about this hobby

 

[dougco1]

Any progress with your issue?

 

[v12venator]

Can someone tell the prpper procedure for setting the cold start advance or the high idle?

Sorry about that, Mshawnm, there is a screw on the front side of the solenoid that you can screw clockwise or counter clockwise with a flat blade screwdriver from underneath your engine side thermostat housing.


The solenoid itself will be on the top of your injection pump and to the right a bit with a green spade connector on top.

Turning it clockwise will increase the adjustment for the cold advance solenoid and turning it counter clockwise will decrease the adjustment. To turn off that solenoid, all you need to do it unplug the green connection on top so you don't have the stuck open problem anymore.