12 valve hard start issue

On the few trucks I've ran temporarily with the fuel shut-off tied up, they all had hard start issues. You might try untying the shutdown solenoid next time you turn it off and then moving the shutoff to the run position next time you go to fire the truck to see if it makes a difference. In my mind it shouldn't make a difference, but it has in the past, almost like the pump can lose prime easier if it's in the run position although mechanically it really shouldn't make a difference.

Also, try bumping your idle up to around 1000 rpm, this will help eliminate issues with the governor arm catching the AFC foot or fuel plate in a weird orientation during slow cranking if your starter or batteries are weak.


Seth usually sends information with the pump about where it was pin timed. When you use math, make sure you account for the pin timing. If it's pin timed at 12* and you back the motor up 10*, you are now at 22*. Some guys have trouble because they try to advance the motor forward to advance timing which is incorrect.

The foolproof way to make sure you are turning the motor backwards which is correct for advancing timing, is to use the alternator nut. The motor can only spin in reverse with the alternator because forward (crankshaft clockwise) direction loosens the belt and it slips.
 
I've always gone off of overall lift.

Make sure plunger is down

Rotate the pump forward to total lift you need for desired timing

Pop gear off

Rotate engine to tdc

Re assemble


I realize the lift charts aren't entirely 100% accurate but every truck is different anyhow on where it likes the timing to be. The lift chart is just a reference to where I am at and where I need to move to make adjustments. Usually I time a truck several times before I am happy with it. The engine doesn't care if the lift chart is off 1, 2 ,3 even 4 degrees. If you think the truck is at 18* based on the chart but the engine is actually at 19 or 20 it doesn't matter. As long as the engine runs best for your setup where it is at. Everyone picking up what I am throwing down? $.02
 
I had the head off when I set tdc, but I'll recheck that tonight, and you're saying to set the timing like I did before, using the equation to do it correct ?


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Yep, makes sense to me, the truck runs awesome it just, doesn't like to start with out a small shot of ether lol. Think it could be sucking air somewhere ? It has a funky idle for a few seconds or if I rev it up it'll go away when it comes back down to idle.


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kole32 said:
Yep, makes sense to me, the truck runs awesome it just, doesn't like to start with out a small shot of ether lol. Think it could be sucking air somewhere ? It has a funky idle for a few seconds or if I rev it up it'll go away when it comes back down to idle.


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I've had 12v trucks act up even with a small air leak somewhere in the return system. They can be finicky. I assume you are giving it some pedal while you crank? The p7100 isn't an instant turn key start at times like you may be accustomed to with the ve.
 
Ya I've been giving it pedal. Is there anything to spray to find an air leak ? A buddy of mine says there is but I can't remember what he said.


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^ he's probably thinking a vacuum leak on gas motor ya spray either to find them. I'd look at the metal line going to sending unit I had that rust a pin hole in my first gen.
 
Ok, I didn't get a fuel pressure gauge, but I unhooked one of my feed lines to the pump and fuel came out like a garden hose, I know it's not a pressure reading but it is getting fuel to the pump, I cracked a couple fuel lines open on top the injectors and I'm getting a dribble out, so looks like I've got air in the lines somewhere. Right ?


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You will be able to see if your injectors are leaking. When the truck is running you will see fuel bubbling around the injector nuts or the return line. If you have a leak in your fuel system somewhere between the lift pump and the injectors a lot of the time the truck will start hard or crank long, not want to idle on its own until it's warm, sputter and choke a little bit, or need extra fuel from the pedal or ether to get started or many other things. Some leaks are pretty hard to find but even the smallest leak will make a difference in starting or how a truck runs. If you're not getting much white smoke or haze then your timing is probably okay but I am definitely no expert. Just a DIY kind of guy that has had a lot of engine problems haha


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Lol ya I'm the same way, I'm Gonna work on it some more tomorrow and see what i can find, I'll let ya guys inow


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Got it fixed, the fuel fitting goin into the injection pump was a little loose, tightened it up and it's good to go, thanks for all the help. Now i got an oil leak to find lol


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