Weak hydraulics on Bri-Mar dump trailer?

[Ken45101]

I have a Bri-Mar Rascal dump trailer which is supposed to handle a 4 ton load (10,000 GVW, 2K empty weight). But if I get over 3 ton in it, it won't lift the bed, I can hear the relief valve chattering. If I get it started up a couple of inches (I used a 2x4 to help it today), it will then go the rest of the way by itself.

It's always been on the weak side (seems like it used to handle 3.5 ton), I'm not sure if it's getting worse.

Are these trailer overrated, or is some amiss with the hydraulics? Is the relief valve weak?

I've thought of repositioning the cylinder mount lower to give it a better angle, or sticking a 4x4 under the bed to keep it raised a few inches.

Any other thoughts/experiences?

Thanks,

Ken

 

[radman1]

Sounds like you may need to increase you relief setting a little. Does the pump run ok at heavy load but just won't quite lift? I have a 14K titan and it will lift whatever I can haul. I tend to load more over the tires and rear rather than the front on heavy loads. It is easy to over load when using the entire dump bed. However, mine still lifts the heaviest loads. Are you overloading you dump trailer? The hardest part to lift is usually when the bed is completely down - as you have noticed!

 

[BarryinMN]

Where the load is positioned in the bed matters more with the straight ram type lift. If you use a scissor type lift you get better leverage and a higher dump angle. Down side is it costs more.

 

[JB4310]

Sounds like the exact same thing as my 5 ton EZ dumper. I also wondered if there is a way to turn up the relief valve?
Like was mentioned it's all in the geometry, look at that cylinder the way it's laying down flat in there and how it's trying to get that load up those first few inches.

Mines failed to dump on at least a few occasions, usually due to overload, but also could easily be caused by poor distribution of load (to much on the front) I've had to manually transfer material from the front to the rear, usually not more than a few hundred pounds.

Mines a 6x10 with just 1 cylinder, it is a pretty large cylinder, but the 12 foot trailers all have twin cylinders and even though they're smaller I don't think they would care if you overloaded or misloaded the box.

JB.

 

[Ken45101]

I don't see anything in the manual about a relief valve or adjusting it.

I try to get the gravel yard to load to the rear, but they are using a big articulated load with a 8' bucket so there's not much say in how it's loaded. Half the time they are spilling over the ends anyway. Yesterday the load was pretty evenly distrubuted and, like I said, it wouldn't lift 3 tons without help.

I'll take a look at it and see if I can find any adjustment for the relief valve.

The design geometry seems poor on these trailers with the cylinder pushing too much horizontally when the bed is down.

I've thought about mounting a cheap bottle jack under the front to get things started

Ken

 

[Q-Saw]

...I've thought about mounting a cheap bottle jack under the front to get things started

Ken

I've thought of that also - except I was thinking of one of those long jacks like they use in engine hoists.

I have used the FEL to give the front of the trailer extra lift - works pretty well if you can get a purchase underneath.

Mostly, though, I'm just real careful not to overload now. Overloading these dumps is simply too easy to do (mine is a 16', so a full load of 10,000 lbs makes the trailer bed look practically empty).

I always talk to the loader operator before loading to tell him exactly where I want the load. Then I watch him load from a position where I can see the load, he can see me, and I'm safely out of his way. I'm sure these guys don't care for me hovering around, but it's not their bacon hauling that load down the highway.

The vast majority of the loader drivers have been really great and do an excellent job. Every once in a while I get the totally bored "you don't need to tell me how to do my job" look. I understand: I don't like people telling me how to do my job, but when one of my customers tells me what they want, I listen and do the job (as long as it's safe).

Just be careful of loading to the rear of the trailer - this can create an unstable situation and the trailer can start swinging side to side. Someone (not a regular yard loader) loaded me too far back one time, and that was all it took for me to be very vigilant every time my trailer was loaded from then on.

Luckily, when my trailer started swinging (a dip in the road started the oscillations) I just took my foot off the gas and applied a bit of brake to the trailer - it straightened right out. I then pulled over to change clothes.
I have been a strong proponent of electric brakes ever since. I have used surge brakes, and no way would they have straightened out that trailer that quickly and safely. Remember, your tongue weight should be 10% to 15% of your trailer weight. How to accurately measure tongue weight is another matter.

I don't think the 4x4 is the safest answer for a number of reasons, but I understand your thinking. When I've had trouble lifting, all it took was to bring it up 6 or 8 inches, and then the hoist cylinders could handle it.

And, I wish I even got a manual with my trailer.

- Marty

 

[Ken45101]

Marty,

Well with the big loader they have at the yard, it's impossible to get the load too concentrated on one end of the trailer. I'm also towing with a C3500 diesel dually, so I have a solid tow vehicle. But I recognize the dangers of loading too much too far to the rear.

Ken

 

[Skyco]

Same situation here on my Southern Sales dump trailer.low-rider
If I'm loaded with the full 5 tons it has a very hard time or sometimes can't lift it. I've noticed if I'm front downhill on a slope it is worse. I found the pressure adjustment valve and cranked it in per the trailer builders advice. That helped but when I measured with a pressure gauge I'm now well over the cylinder rating. So when it has trouble, for now, I place a Hi-Lift jack under one corner to "help". As soon as its up 4"-6" or so it goes on up.
So I'm considering a couple of things, one is to buy a larger diameter cylinder to give it more lift. Another is to cut loose the cylinder mount and lower it to get the angle better, but that will cost a little lift angle. Mine is a scissor lift BTW. For now I'm just living with it.

The Vulcan quarry where I get my stone products absolutely forbids getting out of the vehicle on the property so theres no coaching the loader driver to make sure he loads it center. If he gets it a little forward I have lift problems for sure, if he gets it a little rearward it sways, and yes they can get it off even with a loader bucket way bigger than the trailer. They usually just fill a corner of the bucket so they don't dump it on the ground on both ends of the trailer. They usually are pretty close on weight but I've had them go way over too.

 

[Q-Saw]

Skyco -

That looks like a nice trailer. Where did they mount the hydraulic pump and battery - are they under the dump box? I couldn't tell from the manufacturer's pictures.

If you could post a picture of where your pressure adjustment valve is located, that may help the OP - it sounds like his setting may have changed for some reason. I have no idea where the adjustment is on mine - if there is one - but i'm guessing most of those pumps are pretty similar.

Also, I'm curious as to where you tapped in for the pressure guage. Did you just pull off one of the hydraulic hoses and attach the guage to the end of the hose? I just bought a guage from Northern Equipment to check the pressure setting on my FEL, I'd be curious to check the setting on my dump trailer.

It sounds like a bottle jack, or Hi-Lift jack may be the easiest route to go to get those stubborn lifts started.

- Marty

 

[Skyco]

Go here- big file 3+MB - and scroll down to page 4 and look at item 5 in the drawing. Mine is on the side with an Allen screw in the locknut-

http://www.haldex.com/en/North-America/Applications-Products/Literature/Hydraulic-Systems-Literature/?pdf=%2fGlobal%2fHydraulics%2fProduct%2520Catalogs%2fHEPOWERPACKS.PDF

Just loosen the locknut and run the screw in some. That will raise hydraulic pressure.

Yes my battery and hydr. powerpack is under the front of the dump bed..I like that because it is secure and out of the way.

As for the pressure gauge, yes I just bought a 5000 lb one and temporarily connected it to the fitting on the pump deadheaded to see where it maxed out.

I bought the trailer with a number of options, got the tailgate that opens like a door or opens as a spreader. The design was poor though as it bent when the force of a load was pressing against it while spreading, I welded a channel iron reinforcement all the way across after fixing. Mine is the 6'10" x 12 ft. Also got the roll up tarp, 14,000 GVW capacity, and scissor lift. If I had it to do over I would have bought the 14' long one, don't think they had that at the time I bought a couple of years ago. I also remade the remote control harness from the supplied 6ft to one about 15ft long, I like to stand at the back of the trailer watching it dump while working it sometimes. Oh yeah mine is black- makes it easier to touch up.

I went and priced some larger lift cylinders last night- $700+
I won't be doing that