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6.5 Diesel Injector Rebuild

dbrannon79

I'm getting there!
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Hey guys I’m looking into the how to’s on rebuilding you own injectors. There some interesting things I’ve found online about them but they seem relatively simple to do with the proper tools of course.

I have read where it has been a problem finding the replacement parts like shims and nozzles. Also mixed talk about the recent manufacturing of Bosch and other known brands where good quality seems to be getting scarce with the onset of covid and the lack of workers who actually take pride in their work vs just being there for a paycheck.

I wanted to create a thread compiling all the information I find on parts and methods for the average DIY’er to possibly rebuild their own
 
Also looking at the cheapest and safest way to build your own pop tester using a HarborFreight small bottle jack. One YouTube video I found uses a method where there is no welding required, they removed the piston and threaded the inner tube to 3/4” not. Used a hydraulic pipe nipple out from the jack tube, tee’ed to a gauge and fitting to an old line. but I am still trying to figure out how to adapt normal pipe threads to get to the right threaded fitting so an old injector line can be used for our injectors. If anyone has any ideas please share 🙂
 
Go learn what ya can from this guy. He has a lot of years doing them and sells kits (read in his description under video) and can save you some time. He doesn’t do everything 100% right, but hits 85-90%
I just grabbed whatever video popped up from remembering his channel name.
Look up peach parts also iirc
 
Oh yeah, the shim surface smaller than the spring — nopers. Spring is harder than the shim. That spring will wear into the shim. If a person had no other option, ok. Better than throwing away parts, But I would continue the quest.

One of thr problems with diy bottle jack is they push a little too much fluid through per pump. Getting it to slow down flow- so you have more handle stroke per event will help it be more accurate.
 
I’ve watched some of his videos. Very good

yeah I was kinda thinking the same thing. What’s the cons of re-using the old shims? I assume the shim is to apply more or less tension on the spring which in turn adjusts the pop pressure. Low pop would need a thicker shim where a high pop needs a thinner shim. Is that correct?
 
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.
20201127_175532.jpg
20201127_175545.jpg

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.
20211130_192910.jpg

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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That nice. For lapping I read somewhere that using a mirror as a flat surface with some 1200 grit sand paper or finer and tranny fluid to lap the body. Not sure if the heat shield can be done the same way to smooth off the surface.

once I can get ahold of some old injectors I can visually learn. Ive never had one apart before
 
 
Looking further into building a pop tester I have been looking at the cost and time to build one vs just buying one of the $100 ones from amazon or ebay. Amazon shows two different ones for around $90 which look identical to the ones listed on ebay. other than I might need to replace the gauge on it for accuracy, has anyone had any experience with them? they all seem to have mixed reviews.

I am figuring I would have about the same amount of money plus time invested into building one where I could just order one already put together and have the line fittings that fit the injectors.

I have collected two sets of used injectors that Big T sent me, one standard set and one marine set that Will requested photos of the wear on when they are dissembled.

I plan to get my hands on a pop tester and test both sets before doing any dissembling along with plenty if photos and possibly video of their before and after operation.

I am curious on the difference between the two as far as the spray pattern and nozzels. I know the pressures are set different between standard and marine (2150 - 2300 from what I have read) I have to still read up and hopefully find some specs or a shop manual on them for repair or rebuild.
 
Looking further into building a pop tester I have been looking at the cost and time to build one vs just buying one of the $100 ones from amazon or ebay. Amazon shows two different ones for around $90 which look identical to the ones listed on ebay. other than I might need to replace the gauge on it for accuracy, has anyone had any experience with them? they all seem to have mixed reviews.

I am figuring I would have about the same amount of money plus time invested into building one where I could just order one already put together and have the line fittings that fit the injectors.

I have collected two sets of used injectors that Big T sent me, one standard set and one marine set that Will requested photos of the wear on when they are dissembled.

I plan to get my hands on a pop tester and test both sets before doing any dissembling along with plenty if photos and possibly video of their before and after operation.

I am curious on the difference between the two as far as the spray pattern and nozzels. I know the pressures are set different between standard and marine (2150 - 2300 from what I have read) I have to still read up and hopefully find some specs or a shop manual on them for repair or rebuild.

Let us know how many of the Marine ones were in bad shape.
 
Ive taken apart stock and marine nozzles and did some measuring. They are basically identical except for a few differences.

*Marine nozzles have .003" more needle lift. And the pintle is .030" shorter.

So all they did for marine injectors is increase lift a small amount, and machine off the second stage of the throttling pintle.
Other than that they identical and throttle fuel on initial opening identically.

304 vs 311
20211212_105555.jpg

Ive measured all the 6.2 and 6.5 nozzles as well as some VW and Mercedes. And I believe I found a better nozzle than the marine that im going to use for my build.
 
Ive taken apart stock and marine nozzles and did some measuring. They are basically identical except for a few differences.

*Marine nozzles have .003" more needle lift. And the pintle is .030" shorter.

So all they did for marine injectors is increase lift a small amount, and machine off the second stage of the throttling pintle.
Other than that they identical and throttle fuel on initial opening identically.

304 vs 311
View attachment 69244

Ive measured all the 6.2 and 6.5 nozzles as well as some VW and Mercedes. And I believe I found a better nozzle than the marine that im going to use for my build.
Please do share, I assume the nozzles are something between the two?

when you order replacements, what are the average cost on them?
 
@Big T just curious, would you happen to know about how many miles were on the marine or the other standard injectors?

Marine had 80K that I put on them. PO had replaced them prior to my purchase, though not sure how many miles on them. I assume it was recent and thus figure they had 90K to 100K on them.

The other injectors I can't remember. I changed them as a pre-emptive measure because I was not the original owner and did not know how many miles on them. They were working fine.

What are they looking like?
 
once I get a pop tester and go into the dissembly, would anyone know what to look for that causes the injector knock? I would assume it's from the nozzle pin getting stuck, but from the noise they make I would think I would be looking for something that has "pounding" marks.
 
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