wheels getting too hot

[luvmynitro]

I have a 03 nitro 929. It has hydraulic surge brakes. I have had the master cylinder, break pads, and calipers replaced and the bearings checked by professionals. I drove to the lake (about 15 miles) and wheels still get hot enough to get steam when i put it in the water. My boat has been in the shop 3 times at 2 different places, one of which was a tracker boat dealer, and gone nearly all summer. I do not know much about working on the breaks and need help!!

 

[dockwrecker]

Re: wheels getting too hot

The common boo-boo when changing the master cylinder is making sure it's compatible with disc brakes. (You stated they changed calipers) The disc brake master has a relief hole in the end of the piston. The drum brake master doesn't, and always holds a little positive pressure which will smoke disc brakes. Take it back to them and have the correct one installed.

 

[Frank Acampora]

Re: wheels getting too hot

Are the brakes actually locking while running or are the discs just getting hot?

Disc brakes dissipate the horsepower that you use to get the car and trailer going. This translates into a LOT of heat. Think: All the heat generated by the gasoline burned to get the car and trainer rolling must be dissipated by the brakes to stop. After just one or two normal stops, if you were to touch the discs on your tow vehicle, you would burn yourself badly. They never get wet while launching, so you don't see them steam though. It is common practice with disc brakes that after going through a puddle, you ride them a bit to heat them up and dry them out.

So: if you are launching relatively quickly after stopping, the trailer discs will still have enough heat to steam in the water.

 

[Bob's Garage]

Re: wheels getting too hot

If you dunking the trailer immediately upon arrival at the lake, you most likely will get "steam". You will also be sucking water into the hubs with the sudden temperature change.

Get an infrared thermometer to take the temperature of your hubs when you arrive at the lake. You can expect temperatures in the 111 to 135 deg. range when measured on the hub. If over 150 deg. I would be worried.

I have noticed that my tires tend to be the same temperature as the hubs, for what thats's worth.

And do not immediately dunk your trailer. Take some time to prep your boat, use the "john", or whatever, then dunk your boat.

 

[ufm82]

Re: wheels getting too hot

I didn't see where he had drums in the first place so that's probably not the issue. If they changed from drums to discs, the entire backing plate would have been changed as well and he didn't mention that.

I have discs on one axle of my trailer and if I come off the road and go directly into the water they will steam a bit. Granted, it takes 5-10 minutes to get the boat ready once I get to the ramp so they do cool a bit beforehand.

If everything has been replaced and was done correctly and the brakes are actually malfunctioning, look at what is causing the brakes to drag. Is your trailer level when you tow or is it tilting downward towards the hitch. That can compress the master cylinder. Do you have a shock in the coupler to help absorb some of the jolt when the master cylinder extends? It may be bad. Or simply, do you ride the brakes and overwork the brakes? Continual light braking will heat up discs very quickly.

One last thing- trailer discs tend to be much lighter than the tow vehicle discs which means they will be less effective as a heat sink- that is it will take less heat to make them hot than a big rotor you would find on a truck. Pads are little, rotors are smaller, less surface area, higher temps...

UFM82

 

[maxum16]

Re: wheels getting too hot

Sometimes when you have brakes done and the caliper is allowed to hang from the brake line, the line developes an internal kink and doesn't allow fluid to leave the caliper when the brakes are released and the brakes stay partially applied causing them to heat up.