DIY injector piston maching? - Diesel Forum

brencoracing09 · 04-29-2008, 05:17 PM

So I was looking at the diy stage one injectors and was going to get the diy kit . My question is what type of maching is required on the injector piston ? I know that they offer 2 options one that you can buy the pistons already machined and the other you do the maching yourself. I and also a buddy who owns a local import performance shop will be doing the work but I was wondering what kind of tools were needed to do the machining etc etc? Any help or anyone who has done this before the help would be greatly appreciated and also what kind of time should I be looking at?

oldblue31 · 04-29-2008, 07:00 PM

I had my machining done as a favor at the local tech college.I believe he said it was a diamond rock grinder he had to use because the intensifier pistons are made of such a hard material.The tip of the piston is ground down to allow more fuel to flow past the tip of the piston.It has to be very accurate.He lined all 8 of mine up together and machined them all at once.It takes a while.

tjbeggs · 04-29-2008, 09:48 PM

Needs to be done on a surface grinder and tolerance between the set is around .0005.

oldblue31 · 04-29-2008, 10:52 PM

Quote:

Originally Posted by tjbeggs

Needs to be done on a surface grinder and tolerance between the set is around .0005.

Yeah, what he said. I could'nt quite think of the name of the machine.I think he said something about it using a diamond stone.

brencoracing09 · 04-30-2008, 08:52 AM

would it be easier in the long run to just buy the new pistons with the injectors?

tjbeggs · 04-30-2008, 08:54 AM

Quote:

Originally Posted by brencoracing09

would it be easier in the long run to just buy the new pistons with the injectors?

I believe so. That way you know they are right. You will also spend about as much getting them machined as buying them unless you have some favors to call in. Plus you will have less down time and tiny little parts laying around wait to get lost

gls · 04-30-2008, 11:22 AM

I attempted it in my lathe but ended up just buying the pre machined pistions. Rebuilding the injectors is one of the best things I did. Finally no more white smoke on startup. Oh and the truck has way more power.

7.3psd · 04-30-2008, 01:48 PM

I've done them in the lathe before. You just have to make sure you have a good bit and get them centered properly.

brencoracing09 · 04-30-2008, 06:07 PM

i am just going to buy them i cant afford the downtime is my main hold up you saw more power with them an no chip?

johndeerebones · 04-30-2008, 07:25 PM

Quote:

Originally Posted by brencoracing09

i am just going to buy them i cant afford the downtime is my main hold up you saw more power with them an no chip?

Not with the ones. The computer doesn't know to call up the extra fuel, so you gotta have a chip. Only way you will see more power is if there is something wrong with yours.

I had 3 nozzle springs broken, nothing else. Those three springs getting fixed though smoothed my rough idle, gave me a little better tip in power down low(better atomization on those 3 I'm sure), and got rid of my startup smoke(with stock programming, still smokes at satrt with a chip, more fuel at cold start ALWAYS equals smoke, not enough heat at startup to burn it all. Unless you have custom programming with provisions to burn it. The broken nozzle springs cause poor atomization of fuel, and less opening pressure. If they are bad enough it can slobber when it not injecting too.

Right now I only have an off the shelf scmt 1705 tuner and it runs pretty well. I can't roll the smoke with it, but just look at some videos and the stage 1s are more than capable of making the car behind you disappear with proper programming.

You can get them machined probably locally, but Jim has done more than a few, and you probably won't save any money. Also the even machining of the pistons has almost everything to do with how well their flow rates match.

brencoracing09 · 04-30-2008, 10:14 PM

i would not risk the piston deal I would rather do it right the first time then have to deal with it over again. I am starting to get a rougher idle and I had my injectors replaced and I know they are not up to spec because they were all flowed, 4 of them were so bad I had to replace them and did not have any option hardly but I am going to just go ahead and do all of them. As long as I do not have any problems and I hope to god I dont with the motor I am planning on doing the chip soon as well. The only thing that concerns me is it seems like if the truck idles for a while and then i go at a stop light and rev it up it will blow whitish/blueish smoke out? is it loading up with fuel or why does it do that?

johndeerebones · 05-01-2008, 10:22 PM

Quote:

Originally Posted by brencoracing09

i would not risk the piston deal I would rather do it right the first time then have to deal with it over again. I am starting to get a rougher idle and I had my injectors replaced and I know they are not up to spec because they were all flowed, 4 of them were so bad I had to replace them and did not have any option hardly but I am going to just go ahead and do all of them. As long as I do not have any problems and I hope to god I dont with the motor I am planning on doing the chip soon as well. The only thing that concerns me is it seems like if the truck idles for a while and then i go at a stop light and rev it up it will blow whitish/blueish smoke out? is it loading up with fuel or why does it do that?

Sounds like it, does it run good? Could be injector related, or dare I say compression related, the cylinders can actually cool down enough to not get full combustion at idle if the compression isn't up to spec, but, if it starts good, and runs fine, I would doubt a compression problem.

oldblue31 · 05-01-2008, 10:56 PM

all 8 of mine were machined together,side by side.I have not had any problems cause they are all exactly the same but if I had to do it again I would buy them pre machined.The machine work is expensive if you have topay for it.Luckily I did'nt.

brencoracing09 · 05-04-2008, 06:32 PM

john about my fuel problem it will not start in the morning unless it is plugged in the truck has 270k on it and has had one set of gp's in it. the reason it wont start is because the gp's are toasted. thats what every person i have talked to has said about it. the truck runs good yes great no. but again the truck is old and she has been worked a lot more then most trucks out there.

DZLJIM · 05-09-2008, 08:30 AM

Your truck might not be the best candidate for a DIY Kit with that many miles. If the motor was maintained to the highest extreme, you might be ok. And I mean oil changes every 2500 - 3k miles tops with good quality oil, new fuel filter every 5k miles, no bad fuel, etc. Otherwise you can count on extra parts/machining needed.
Especially since you said you had 4 replaced. Were these just used injectors you threw in, or were they Ford remans?
Hope they weren't Ford remans, those are hands down garbage, most of the time.
You can cut the Pistons on a lathe, but you really need to know what you're doing. A surface grinder is just a better tool, or cut most of the Piston on a lathe, then finish on the grinder.
You can definitley rebuild your injectors with a DIY Kit regardless of the mileage, it just takes a lot more work and a lot more machining. If you don't own the equipment or work in a shop, it could get costly.
Just my opinion.