My 1999 480 Sedan Bridge has has the TNT platform and I need to know what hydraulic fluid I should use. Can anyone help me with this?
TNT Hydraulic Swim Platform
- Thread starter TimCS55
- Start date
Alex F
Well-Known Member
- Nov 14, 2006
- 9,166
- Boat Info
- 2005 420DB with AB 11 DLX Tender, Raymarine Electronics (2x12" MFDs) with Vesper AIS
- Engines
- Cummins 450Cs, 9KW Onan Generator, 40HP Yamaha for tender.
For SeaLift I'm using FRAM hydraulic fluid AW46.
If you don't have a manual for yours, perhaps there's a sticker on the motor.
If you don't have a manual for yours, perhaps there's a sticker on the motor.
Thanks Alex. I’ll look for a label.
PlayDate
Well-Known Member
For TNT lifts: Mobil DTE 24 Hydraulic Oil Light
Thanks John
John maybe you could help me with something else. The platform doesn’t move up and down evenly. The starboard side lowers faster than the port side. When the starboard side bottoms out the port side continues lowering until it bottoms out. Same happens when bringing it back up. Last summer the port side lowered faster. I just had the seals replaced in the cylinders this spring and I believe the reversal could be a result of the cylinders being switched when they were reinstalled. Is there anything you can tell me?
PlayDate
Well-Known Member
That’s exactly what happened…..after the rebuild…..they installed them on the opposite side.
Just about every TNT system I have seen…..one side lowers faster and raises faster than the other side. Effectively the pressure is the same on both rams but the internal tolerances cause the uneven lifting.
If it was the actual frame binding……the slow side would remain the same regardless of where the rams were placed. On the frame itself…..TNT could have done a better job of controlling lift movement based on uneven ram movement.
Use makes a difference. The more you use the rams the better.
Just about every TNT system I have seen…..one side lowers faster and raises faster than the other side. Effectively the pressure is the same on both rams but the internal tolerances cause the uneven lifting.
If it was the actual frame binding……the slow side would remain the same regardless of where the rams were placed. On the frame itself…..TNT could have done a better job of controlling lift movement based on uneven ram movement.
Use makes a difference. The more you use the rams the better.
I wonder if there is any kind of after market device that could be installed in the hydraulics that would allow pressure adjustment to each individual cylinder?
PlayDate
Well-Known Member
On the TNT lift the rams connect to a manifold located next to the pump. On some models the pressure could be adjusted to each of the rams. Note the L1 and L2 adjustments below.
My setup doesn’t have any pressure adjustment. I would think there’s got to be some aftermarket product out there.
PlayDate
Well-Known Member
Do you have a picture of your pump and manifold? Plenty of adjustable hydraulic manifolds appear to be available. TNT may even sell you one.
I’m not at the boat but I will get a pic for you.
PlayDate
Well-Known Member
That is definitely an early model. I would spend the picture to TNT and ask them if this manifold block is adjustable. It looks like it has set screws on the face of it which may be adjustable.
If not, ask them if they have a replacement block to use. Tell them you already have had the rams rebuilt and the system flushed and that the uneven lifting predates the rams being rebuilt.
Let me know what they say. The block has two inputs and four outputs.....not very complicated to replace.
If not, ask them if they have a replacement block to use. Tell them you already have had the rams rebuilt and the system flushed and that the uneven lifting predates the rams being rebuilt.
Let me know what they say. The block has two inputs and four outputs.....not very complicated to replace.
Yeah it was probably factory installed back in 1999. Unfortunately TNT was bought a long time ago. The service people at my Marina had spoken to someone from a company that bought them. That was last summer and they helped as much as they could but didn’t even have documentation. I had fabrication work done this spring of the structural pieces that support the main horizontal arms the platform sits on. So if there is a retrofit manifold block that would work that would be worth investigating. I really appreciate your help.
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PlayDate
Well-Known Member
You may want to reach out to this CSR member: @Hydraulicpro
Thank you John. You’ve been very helpful.
