Ark 508

[bo dawg 477]

This is the Ark 508 loader I aquired couple weeks ago. Is this the way they all bolt up to the sub frame? Seems weak to me, plus looks like PO had to do some welding. But looks to have bend the frame a little. Its been worked hard Im sure but what has other guys done to improve this? The oil drain is on the bottom of this side as well.

[Goldnboy 746]

I would add a small section of  the same diameter  and gauge tubing an weld or bolt to subframe for added strength  since this is already a weak spot.

[bc.gold 3,399]

Arc 700.

 

 

 

[bc.gold 3,399]

Take the guess work out of bucket levelling.

 

 

 

[Lee1977 6,217]

A bad design of the subframe caused it to break. Need to redesign the subframe to be under the upright.  Might be better to just start over with a new subframe.

[bo dawg 477]

6 hours ago, bcgold said:

Arc 700.

 

 

 

 

Thats a whole different loader there. Bigger and Heavier.

[bo dawg 477]

Guys I appreciate the input, but I already know how to fix and improve it. My question was is it "Ark 508" factory correct?

Plus if I add support I will block the oil drain plug thats on the bottom unless I drill and tap a plug at the side.  

[bc.gold 3,399]

14 minutes ago, bo dawg said:

Guys I appreciate the input, but I already know how to fix and improve it. My question was is it "Ark 508" factory correct?

Plus if I add support I will block the oil drain plug thats on the bottom unless I drill and tap a plug at the side.  

 

 The loader appears to be factory correct, can't vouch for the sub frame which looks to be a backyard fabrication. The design of the sub frame defies the laws of engineering.

 

 

Edited October 27, 2020 by bcgold

[bc.gold 3,399]

Hope this answers your question.

 

[Skipper 1,788]

Newer understood why there is no consistency in the way these loader setups are often put together. Often you see a strong build loader with over dimensioned uprights, connected to a flimsy subframe with a single bolt, and a small tube bashed flat in the ends as the diagonal to the low front, which is actually the key piece of kit here to transfer the load into the right places.

 

The loader it self often looks fairly OK. BUT the single bolt to the subframe is like a bicycle chain link in a motorcycle chain. Then the diagonal to the front - that thing often needs to take up pretty much all the forces you put onto that loader, including slamming the machine into something solid. If it breaks, or the small bolts break, the loader comes a lot closer to the operator. 

 

I would have made those two parts, or at least the joints of these parts, a lot stronger. 

 

Didn't mean to make this a bash against loaders. I love loaders, but when my sense of self preservation cringes toes, I can't help but speak my mind. 

[bc.gold 3,399]

5 hours ago, bcgold said:

Plus if I add support I will block the oil drain plug thats on the bottom unless I drill and tap a plug at the side. 

McMaster-Carr

Low-Pressure Iron and Steel Threaded Pipe Fittings

Use these fittings for low-pressure applications in noncorrosive environments.

 

Adapters for tanks create an inlet or outlet connection on the surface of any tank, pressure vessel, or drum. Adapters with weld end allow for a permanent connection.

 

Adapters with extension fit tightly into the hole, which keeps the fitting steady during welding.

 

NPTF (Dryseal) threads, NPSC (National Pipe Straight Coupling) threads, and NPSL (National Pipe Straight Locknut) threads are compatible with NPT threads.

 

 

For technical drawings and 3-D models, click on a part number.

Straight Adapters with Extension for Flat Tanks

 

• For Use With: Diesel Fuel, Gasoline, Oil, Water
• Specifications Met: ASTM A181, ANSI/ASME B1.20.1

Pipe Size	For Hole Dia.	OD	Lg.	Material		Each
NPT Female × Weld
1/8	15/16"	1 5/16"	3/8"	Steel	12555K79	$3.16
1/8	15/16"	1 1/2"	9/16"	Steel	12555K69	3.70
1/4	15/16"	1 5/16"	3/8"	Steel	12555K81	2.48
1/4	15/16"	1 1/2"	9/16"	Steel	12555K71	3.70
3/8	15/16"	1 5/16"	3/8"	Steel	12555K82	3.20
3/8	15/16"	1 1/2"	9/16"	Steel	12555K72	3.23
1/2	1 1/8"	1 5/8"	7/16"	Steel	12555K83	3.55
1/2	1 1/8"	1 3/4"	5/8"	Steel	12555K73	3.23
3/4	1 5/16"	1 15/16"	1/2"	Steel	12555K84	3.92
3/4	1 3/8"	2 1/8"	11/16"	Steel	12555K74	4.00
1	1 5/8"	2 3/8"	3/4"	Steel	12555K75	5.40
1	1 11/16"	2 1/4"	9/16"	Steel	12555K85	5.38
1 1/4	2"	2 9/16"	9/16"	Steel	12555K86	8.60
1 1/4	2"	2 11/16"	3/4"	Steel	12555K76	5.70
1 1/2	2 1/4"	2 13/16"	9/16"	Steel	12555K87	8.28
1 1/2	2 1/4"	3"	3/4"	Steel	12555K77	8.53
2	2 5/8"	3 3/8"	5/8"	Steel	12555K88	8.32
2	2 5/8"	3 1/2"	27/32"	Steel	12555K78	10.12
2 1/2	3 1/8"	4 1/16"	1"	Steel	12555K89	13.28
3	3 5/8"	4 5/8"	1"	Steel	12555K91	14.02
4	4 11/16"	5 13/16"	1 7/32"	Steel	12555K92	20.68

 

Straight Adapters for Flat Tanks

 

• For Use With: Diesel Fuel, Gasoline, Oil, Water
• Specifications Met: ANSI/ASME SA105, ANSI/ASME SA181-70

Pipe Size	For Hole Dia.	OD	Lg.	Material		Each
NPT Female × Weld
1/4	3/4"	1 1/4"	5/16"	Steel	12555K51	$6.78
3/8	15/16"	1 1/4"	3/8"	Steel	12555K52	9.18
1/2	1 1/8"	1 1/2"	1/2"	Steel	12555K53	4.31
3/4	1 3/8"	1 3/4"	5/8"	Steel	12555K54	4.31
1	1 11/16"	2 1/8"	5/8"	Steel	12555K55	4.75
1 1/4	2"	2 1/2"	3/4"	Steel	12555K56	6.58
1 1/2	2 3/8"	3"	3/4"	Steel	12555K57	9.93
2	2 7/8"	3 1/2"	13/16"	Steel	12555K58	11.43
2 1/2	3 1/2"	4 1/4"	1"	Steel	12555K59	16.00
3	4 1/8"	4 3/4"	1"	Steel	12555K61	18.72
4	5 1/8"	5 3/4"	1 3/16"	Steel	12555K62	31.70

 

 

Straight Adapters for Curved Tanks

 

• For Use With: Diesel Fuel, Gasoline, Oil, Water
• Pipe Nipples and Pipe: Use Schedule 40 steel

Pipe Size	For Hole Dia.	For Tank OD	OD	Lg.	Material		Each
NPTF Female × Weld
3/4	1 1/8"	20"	2 3/16"	7/16"	Steel	1698T11	$2.81
NPSC Female × Weld
1 1/4	1 11/16"	36"	2 13/16"	1/2"	Steel	1698T12	3.38
1 1/2	1 15/16"	36"	3 1/4"	1/2"	Steel	1698T13	3.75
2	2 7/16"	26 1/2"	3 11/16"	5/8"	Steel	1698T14	3.78

 

 

 

Edited October 27, 2020 by bcgold

[wallfish 15,921]

My guess is the previous owner found out it bends there when the front supports aren't attached or attached correctly. With a loaded bucket the weight and force is on those angle supports to the front so a major crazy connection where you have pictured is not completely necessary. The design is so it can be removed from the tractor quickly and easier. With the front angle supports in place correctly, it's doubtful you could bend that lower connection with the original hydraulics if you tried. I would beef up the front support those angle supports go to on the front of the tractor since that is what takes all the load.

 

[953 nut 51,716]

My Johnson loader has a heavier sub-frame, but the attachment point looks about the same.

Edited October 27, 2020 by 953 nut

[bo dawg 477]

4 hours ago, wallfish said:

My guess is the previous owner found out it bends there when the front supports aren't attached or attached correctly. With a loaded bucket the weight and force is on those angle supports to the front so a major crazy connection where you have pictured is not completely necessary. The design is so it can be removed from the tractor quickly and easier. With the front angle supports in place correctly, it's doubtful you could bend that lower connection with the original hydraulics if you tried. I would beef up the front support those angle supports go to on the front of the tractor since that is what takes all the load.

 

 

That makes sense! Theres been more steel welded to the ends of the brackets where your arrow points to. This thing was worked too hard at some point in its life I believe.

[bo dawg 477]

8 hours ago, bcgold said:

Hope this answers your question.

 

 

Yep looks like the same sub frame I have and attachment point. Thanks!