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6.5 Diesel Injector Rebuild

I've read online that nozzles can be a hit or miss from ebay not knowing if they are genuine, good, or a no no. I did find a youtube video a while back of someone "lapping" the nozzle and pin using some kind of compound that looked like polishing or rubbing compound for paint finishes. I will have to look for that and post it to get opinions of that.
 
dbrannon79 said:
I've read online that nozzles can be a hit or miss from ebay not knowing if they are genuine, good, or a no no. I did find a youtube video a while back of someone "lapping" the nozzle and pin using some kind of compound that looked like polishing or rubbing compound for paint finishes. I will have to look for that and post it to get opinions of that.
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Yes I know what you mean.I bought the Bosch India nozzles maybe 10-12 days ago.The pictures show the Bosch logo etched into the nozzle along with the part number so they look legitimate but your right.There’s no telling what can arrive in your hands once you make the purchase.
 
That appears to be the kind I purchased.I dug that Bosch part number up after doing some googling about shims and heat shields for 6.5 nozzles.The guy I got the Bosch number from says they are the correct heat shields.
 
It’s a great video👍I should have pop tested my stanadyne injectors before I installed them back in 2015 in my 96 K1500.They weren’t cheap at over $600 for the set at the time from accurate diesel in Michigan.The truck runs rather smooth but they still could be off in regard to pop pressure.
 
As far as the “right pop pressure” All the old numbers are no good. The viscosity of modern fuel is different that old school #2. You really have to have two sets, one in the truck and one you are re adjusting.
taking the time to figure out what is best is really worth it.

And you’ll find what works best in one engine won’t be the same in another with different turbo, different compression, different ip, etc.
 
that explains why thicker "oilier" fuel runs better. I remember reading a forum thread somewhere that a guy had added a good load of oil, I think veg, oil in his diesel and it ran smoother and less rattle. I can't remember where I read that, but 10 - 20 % seems to ring a bell.
 
Pop pressure is going to be determined off of your pump specs. When you turn up a DB2 it compresses the leaf spring more increasing the roller to roller spec. By doing this the roller contacts the camring lobe earlier causing the start of injection to advance, If you swap the leaf spring and shoes it increases it even more. Same goes for a tuned DS4 it just works a little different because the fuel solenoid controls fueling output. So in order to get the start of injection back into spec with out changing base timing pop pressure is increased which retards the start of injection. Like I said before as far as what that spec should be has yet to be figured out. The best way to go about it would be to put a pressure transducer in one of the injection lines and scope it along with the crank sensor. That way you can see what degree the start of injection happens and for how long.

All fuel system parts "should" be calibrated with the proper SAE J967 ISO 4113 calibration fluid. The pump calls for it to be at 100*f, I've never found any information that specs the temperature for calibrating the injector pop pressure. But since your just setting pressure and not flow like a pump I imagine #2 diesel at room temp will work just fine for calibrating your own injectors.
 
Rockabillyrat said:
I built my own pop tester from a HF bottle jack. But I went about it a different way. My father machined up a new shaft that made the whole project alot easier. It uses the original seals on the lower and upper ends. He machine in a retaining flange to prevent the shaft from moving upwards. And a through hole tapped to 1/4 NPT. Even added a spot to hold the shaft with a wrench.
View attachment 69054
View attachment 69055

All the fittings are 1/4 NPT stainless, and I found a m12×1.5 - 1/4 NPT Male to Female adapter. WIKA pressure gauge, small filter coming out the bottom of the reservoir I made using a 2 stroke mixing bottle. Then had a custom m12×1.5 -m14x1.5 line made. Held it all together with some hose clamps and a piece of 1/16" stainless. Im happy with how it turned out.
View attachment 69056

As far as a source for shims, heat shield washers, and compression washers your best bet is ordering from Europe. Some of the bigger diesel supply stores offer shim kits and 10 packs of the other 2 washers. You need the correct 11.5mm od shims. Luckily VW and Mercedes IDIs use the same style injectors so they are easy to find. I've had no luck finding a good shim kit here in the states. I've reached out to a few pump builders and they all told me to order from Europe.

Nozzles you can source here in the states from any bosch distributor. Stanadyne also makes nozzles for these injectors that ive heard are just as good as the bosch. I might order a set for my build to see what I think of them

Oh and a GOOD lapping stone is a must for injector rebuilds.
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Any idea where to buy new stanadyne nozzles?I was just curious.Delphi nozzles are discontinued when I emailed a seller in Europe a few weeks ago.You can probably buy Complete Delphi injectors but the nozzle part I’m told you can’t get.So I know bosch nozzles are widely available but stanadyne I heard is very expensive.
 
I've heard good things about monark nozzles and I noticed that the seller in Germany carries monark . He doesn't have any specifically for 6.5s but I thought I read somewhere that some of the Mercedes nozzles we're the same. Any input on that?
 
Monark makes good nozzles from what I've heard, Both the VW and Mercedes use the same nozzle as the 6.5. As long as the nozzle starts with DN0SD it will work in a 6.5. You just have to check if its a long or short style. Most of the Euro IDIs use long body injectors. Unfortunately there is no good aftermarket source for the 311 marine nozzle. That you will have to get from bosch or stanadyne.

I have a set of Mercedes nozzles here at the house I'm playing around with.
 
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Rockabillyrat said:
Bosch, Delphi, and Stanadyne nozzles are all available from any local fuel system part distributor. I order all my parts from a place here in Ohio that is a distributor for all three companies. Stanadyne marine nozzles are the same price as Bosch.
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When I inquired for complete new stanadyne injectors from accurate diesel the people there told me a couple years ago they were much more expensive than Bosch.The Bosch was about $450 for the set while the stanadyne injectors were over $900 by the time they were shipped to me.I’ve bought two sets of stanadyne injectors from accurate.I sold my 93 K1500 truck with a set of those installed over a year ago.
 
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dieselolds said:
When I inquired for complete new stanadyne injectors from accurate diesel the people there told me a couple years ago they were much more expensive than Bosch.The Bosch was about $450 for the set while the stanadyne injectors were over $900 by the time they were shipped to me.I’ve bought two sets of stanadyne injectors from accurate.I sold my 93 K1500 truck with a set of those installed over a year ago.
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I never priced out the complete injectors. But the nozzles are very close in price between the two.
 
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