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Marzoccchi DH3 Repair

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Marzoccchi DH3 Repair

Old 01-30-19, 01:52 AM
  #1  
tp4surf
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Marzoccchi DH3 Repair

I've got my eye on a nice 26er Parkpre 825 Pro, circa 1995-96. The 825 Pro was special due to its "Tange Ultimate" cromo frame which weighed in at 4.5lbs. My intent is to build a fire road bike, one that has a low center of gravity and has a front suspension fork to handle the hard-packed adobe ruts. The Parkpre 825 Pro came with a choice of forks; Marzocchi 3, Rock Shox and Manitou Answer 3. It also came with a Parkpre proprietary cromo fork, which is what the bike in question has. I've also located a nice Marzocchi DH3 fork, which matches up nicely with the Parkepre frame, and with 3" of travel, weighing only 3.5lbs, and "Fully hydraulic air sprung/oil dampened multi-valve design" should fit its intended use. The only problem is that the Marzocchi fork is missing one of it rebound adjusters (yes, one on each leg) I was able to locate a replacement from a shop in Germany that specializes in Marzocchi forks, but they want US$30 for the part and US$22 for shipping. That's almost as much as I would pay for the fork. And I probably will need to invest in some new seals. I'm trying to keep the total cost of this build down to $300-$350, so I'm wondering if anyone knows of a source for the part in the USA? See the photo below for reference.Not opposed to a hack to work around this issue...


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Old 01-30-19, 07:38 AM
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wow thats great
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Old 01-30-19, 11:31 AM
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Marzocchi Mark!

If he doesn't have what you need, start shopping for a new fork.

https://www.mtbforksbymark.com/
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Old 02-11-19, 02:56 PM
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So, as a newbie to suspension fork maintenance, I’m more than a little perplex over what I seem to have gotten myself into. This Marzocchi DH3 fork is missing one of its dampener adjuster assemblies (see photo above), so I ordered a replacement from “MarzocchiMark” (thanks AggieGrads). While waiting for said adjuster, I also ordered a nice 300# shock pump (only need 51# according to service manual). I found that the drive-side fork leg will hold air pressure momentarily, but it quickly leaks out. The non-drive-side leg with the missing adjuster doesn’t hold any air (and most likely no oil either) due to the missing adjuster assembly. Now, here’s the perplexing part; the fork acts pretty normal as is. The fork came with the obligatory a zip-tie on one of the stanchions to serve as a compression travel indicator. There’s no compression when I sit on the bike (190# rider), as if the pre-load is set to “0”. But, the fork compresses maybe 20mm-30mm when cruising the neighborhood going over pot holes, cracks, curbs, etc. Total advertised travel is only 77mm. Rebound seems good, although the lack of oil in the problem leg would make dampening suspect at speed in most offroad conditions. Is it possible that some previous owner converted this “air sprung/oil dampened multi-valve design” fork to a steel spring fork? My research has found that this was a mod for this fork utilized in the past. I’m trying to avoid tearing down the fork just to confirm this possibility, evoking the “if-it-ain't-broke-don’t-fix-it” rule. Although, it occurs to me that after the new adjuster assembly is installed, I will need to remove the air-valve assembly to add oil. Perhaps that will reveal the answer?


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Old 02-11-19, 06:12 PM
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I'd attempt to take it apart. That way all these little surprises don't sneak up on you.
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Old 02-20-19, 12:04 PM
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Update...There were a couple of aftermarket kits to convert the DH3 to coil spring, but some would simply use the springs designed for an early Marz Bomber. Simply remove the top air-valve assembly (TAVA), insert spring, and re-install TAVA. This "ghetto" mod (we use to call it "shade tree") left the fork with no "sag" or pre-load adjustment. But, it was considered more cost effective than replacing seals if there was an air leak. Many also believed that the addition of coil springs to the DH3 was a definite improvement in a sus fork already considered to be ahead of its time. However, the fix canceled out one of the forks most attractive features; its lightweight. I had one well-respected fork mechanic tell me that the circlip that retains the top air-valve assembly would not withstand the forces exerted by the coil spring, and yet 20 years later the mod on this fork has yet to fail. I will say that pushing the TAVA far enough into the stanchion to remove the circlip seems almost impossible. Removal of TAVA and full compression of the fork is required to achieve the correct oil level (and to drain the existing oil). I fashioned a "dip stick" from a coat hanger, and then guesstimated the distance from the top of the stanchion to the correct oil level, allowing for the 77mm of travel of the fully extended fork. Adding 77mm to 33mm, I came up 110mm as the distance from the top of the stanchion to the level of the oil in a full extended DH3. I made marks on my dipstick at "0" and "110", then I added oil by removing the valve stem and attaching a rubber tube between the Schrader valve and a plastic syringe (oil injection?). When the oil level in each stanchion reached the 110mm mark, I declared victory. I replaced the valve cores with new ones, in the hopes that a defective valve core was the cause of the air leaks. But, that was not to be the case, as neither stachion would maintain 40psi for more than a moment before leaking back down to 5psi. With everything back together, I took the Parkpre for a ride on my local river-bottom single-track. My fork travel indicator zip tie hit a high of 34mm, so no bottoming-out. (This is probably more reflective of my cautious riding style). Rebound was vastly improved, so the oil dampening was working. No oil leaks after about 60min riding. While an obscure topic, I hope this is helpful to someone else.


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Old 02-20-19, 05:59 PM
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Glad you figured everything out!
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