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Hiab 335K crane leaking

Newguy

Active Member
Joined
Oct 4, 2011
Messages
26
Location
Ab, Canada
Occupation
shipping-machinery
Hi, iam trying to repair some leaks on a Hiab 335K truck mounted crane and iam in need of the repair manual, i was told by a retired crane tech that Hiab never produced any manuals, is this correct because it doesn't sound right to me that the most well known truck mounted crane company won't make any service manuals for it's products !? does anyone know if there's any type of literature on these cranes ? or is my mechanic friend retired for a reason haha anyone came across a similar situation before?

Thank you.
 

RZucker

Senior Member
Joined
Jul 7, 2013
Messages
4,077
Location
Wherever I end up
Occupation
Mechanic/welder
He may not be far off, I worked on a Palfinger crane once and didn't get much support, but my Hydraulic service center had the cylinder seals covered.
 

Newguy

Active Member
Joined
Oct 4, 2011
Messages
26
Location
Ab, Canada
Occupation
shipping-machinery
He may not be far off, I worked on a Palfinger crane once and didn't get much support, but my Hydraulic service center had the cylinder seals covered.
Thank you for the reply, that sounds about right because i asked the local dealer yesterday a little after i posted this thread, a tech told me that Hiab actually never made any manuals :confused: and that all the service expertise their techs have is just accumulative know how from years in service :(:mad:, they did say that they contacted Hiab occasionally but besides that nothing !! someone else told me there's like a software system much like Caterpillar's SIS, i need to dive deep into that crane so i guess i need to find some sort of literature some how.

Thank you.
 

crane operator

Senior Member
Joined
Mar 27, 2009
Messages
8,315
Location
sw missouri
Its not unusual in european built equipment to not have any manuals. The old Cat and Grove repair and service manuals, walked you step by step through a lot of repairs. Also a lot of the old paper engine books were excellent.

The early Krupp and GMK (german built) all terrain cranes had no service manuals, if you were lucky, you might have a wiring diagram and a hydraulic schematic. The new ones you have to send your own mechanic to school, or you only have dealer access to the computer version repair manual, printed manuals are rare.

That said, what are you needing a manual for? The smaller older Hiab's aren't very complicated, the newest, real big ones are a different beast, especially if they are remote/ dual controls.
 

Newguy

Active Member
Joined
Oct 4, 2011
Messages
26
Location
Ab, Canada
Occupation
shipping-machinery
Its not unusual in european built equipment to not have any manuals. The old Cat and Grove repair and service manuals, walked you step by step through a lot of repairs. Also a lot of the old paper engine books were excellent.

The early Krupp and GMK (german built) all terrain cranes had no service manuals, if you were lucky, you might have a wiring diagram and a hydraulic schematic. The new ones you have to send your own mechanic to school, or you only have dealer access to the computer version repair manual, printed manuals are rare.

That said, what are you needing a manual for? The smaller older Hiab's aren't very complicated, the newest, real big ones are a different beast, especially if they are remote/ dual controls.

Crane Operator, thank you very much for your informing reply,
I don't have much experience with cranes in general all i did in the past was replace hoses and i was going to install a remote assembly on a Hiab 335K like the one in question last year that it. After one week of searching i figured it's going to be difficult to find any printed material, i was told by the parts tech at the dealership that if they needed help they would contact Hiab, so it was obvious that they do have literature but it's privileged and they're not able (or maybe unwilling) to share them, even though i'll buy all my parts from them and i've dealt with them since 2013, hence my reluctance to contact Hiab but i will contact them especially after Welder Dave thankfully advised it, if i can't find manuals i was going to start taking things apart while documenting everything meticulously, it is going to take me longer to finish the job this way but it will be done.

The crane is a 335K-4CL, S/N: 3350483, there's a leak in between the second and third boom extensions and i looked from the top where the first stiff stage connects with the extensions assembly and found the rubber hoses dry and not looking to be the cause of the leak, i need to take the extensions apart to locate the leak and fix it, i'll need the assembly- dis assembly and preferably the hydraulic schematic as well, this truck was purchased recently and prior to that it sat for a good 2 years under the element so i need to do a general check and replace everything that might be a little questionable since we're taking it a part.
 
Last edited:

Newguy

Active Member
Joined
Oct 4, 2011
Messages
26
Location
Ab, Canada
Occupation
shipping-machinery
Hi again everyone,

I thought i'd post an update on this job, eventually i did find some Hiab diagrams of the crane extensions but with zero instructions or details, i managed to remove the boom cylinders as an assembly, there were two cylinders leaking between the cylinder head and the cylinder's inner wall, when i took the main leaking cylinder apart i found the cylinder head o-rings which are supposed to keep the hydraulic fluid sealed inside the cylinder were pinched between the head and the cylinder wall ! so i ordered 4 seal kits from the local dealer and rebuilt all 4 cylinders, i installed them back into the crane and kept working all the functions for few days and there was no leak to be seen, so this repair was successful.
Still not liking the fact that a reputable equipment manufacturer like Hiab doesn't make or offer any repair manuals.

Thanks again for everyone who tried to help.
 

Newguy

Active Member
Joined
Oct 4, 2011
Messages
26
Location
Ab, Canada
Occupation
shipping-machinery
Here's what the cylinders assembly looks like partially disassembled, and a photo of the damaged o rings.
 

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Hiab tech

New Member
Joined
Sep 15, 2021
Messages
1
Location
Wisconsin
Did you make sure the oil cooler fan is working? Also you can always call hiab tech support for information on this in the future. 1-844-HIAB911
 

Monkeywithawrench

Senior Member
Joined
Nov 8, 2019
Messages
313
Location
New Hampshire
HIAB TECH.............question for you...........or anybody!!
So I'm working on a HIAB 335K-4 HI PRO. Just started working on this ..........this afternoon. Trying to get the cylinders out from the 4 (could be 5) section main boom...........the very top one that extends all the way out. (not quite sure what the nomenclature is for HIAB boom sections). I took the 2 pins out with that crazy socket that you need. One pin is at the base where the booms pivot and the other is at the tip of the boom that telescopes all of the sections.
So does the cylinder pack come out of the tip of the boom?? I can't get it to move..........well, it moved maybe an 1-2"s (1/2 a pin hole)...........that's it. Or do you need to slide all of the sections out except for the piece that pivots on the first boom section............and if I were reading this, I'd be confused.

So I want to remove the telescoping cylinders inside of all of the telescoping sections.............it looks like it would come out the top (tip) of the boom. Won't move. Am I missing bolts holding the assembly in?? Other the the 2 bolts at either end???
 
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