javamann

Hi all,
I finally installed my new Mach 1.5 from Don (love them) but now I have what could be a problem. With the stock injectors I would have to crank a warm engine about 1/2 second for it to start. With the new injectors I have to crank for 2-3 seconds to start. I have put over 50 miles on the new injectors and this still happens. Any Ideas?

Thanks

joefarmer

1. The old injector tube o-rings allow the injector lines to loose their prime. If this is the case you'll see fuel leaking around the hold down nuts.
2. There may still be air trapped in the lines. If this is the case, it normally works itself out of the system after awhile (5-10 starts). I've noticed it go away sooner on my truck if it's run hard after messing with the fuel system.

brandon.

Don M

Hmmm, thats new one. I have not heard this before.

Somethings that comes to mind; The connector tube to the injector body interface is very important. A small piece of dirt/trash between the two can cause a pressure drop. Corrosion on the tube itself can also cause this. TQ of the tube nut is also important.

I would drive it a bit and see how it acts. If it does not get better...you may check those things.

Removing the connector tubes completely would be required. I use a smal piece of 600-1000 grit wet sandpaper and WD 40 to polish the tube ends. Clean the crud off. Using new o-rings on the connector tubes like joefarmer suggested is a good idea as well. I have taken in several sets of injectors that did not run well, had idle troubles, or just did not make good power. Every one of them so far has been a connector tube to injector body connection problem. I have also found drag marks were the connector tube was not pulled back completely from the head and the injector was pulled out. This caused the tube to drag across the injector. Causing damage to the tube and the injector.

HTH,

Don~

javamann

Thanks, I will try that. BTW, when you install the injectors do you tighten the tube first or tighten down the injector first?

Thanks again.

Don M

Lightly tighten the connector tube first. Then lightly tighten the injector hold down.

Then final TQ the connector tubes. Lastly the hold downs.

This seems to help the alignment and seal best.

The connector tube o-rings are just there for the spit back circuit back to the tank. Leaks to outside are ususally those little rings if everything is tight. The connection between the tube and the injector is fluid tight. The o-rings do not seal in the high pressure. Just the low pressure spit back/return.


Don~

Mike Holmen

Hey Don hows things, I have a question for ya. I just bought a set of injectors off Tim (mach 6'ers). My injection pump is too small for big power (heh heh) and I was wondering whats the big ticket for the real cummins grunt power. I'm running the stock 027 pump and everyone tells me a different story. I really don't want to run a P pump. PDR wants to throw on a stupid pump onto my truck but that kinda old school thinking. I want to just run #2 fuel and maybe a little nos for fun. Tim told me that I can buy his mach 7 when he's tired of them.

Timinva

Mike, your 027 pump will be fine with mach6s. The 028 pump (Ho) will have a problem suppling mach 6s. Call me when you get time. Tim