XR Top Cap

[Summer Heat]

I hear allot about making sure top cap is properly torqued to help prevent major headaches.

My setup has Latham stearing with a six bolt top plate of which 4 bolts are in XR cap. Are these the mounting points I should monitor or is there something hiding underneath?

[RedDog382]

These are the correct points to keep tight. Some feel the stock top caps are not strong enough and a aftermarket top cap is stronger. It stabilizes the upper shaft in the housing, theoretically lessening the likelihood of failure. Usually the L-hand prop turns in a direction to load the torque on the top cap. GLH actually broke the top cap. I have upgraded mine to Max Machine Worx top caps as I am turning 645 H.P. and over 600 ft/lb torque on a 10,400 boat (382 Formula). The are $400 each. Others to consider are Teague and Billet Marine.

[mcollinstn]

Hey, Red,

I assume you did get my check?
Merry Christmas.

mc

[RedDog382]

Hey, Red,

I assume you did get my check?
Merry Christmas.

mc

Yes, I recieved the check. Thanks! Get them bolted on yet?
Happy Holidays and a very good New Year to you too, my friend!

[Mr Gadgets]

SummerHeat,
What Red says is correct. The stock caps are not the strongest. The Merc ITS cap has a steel tower in it. The aftermarket caps are much thicker. When it comes to LH rotation the top cap is a weak point.
One thing to point out that not all caps are made the same. There are differences in the clearances from the Merc to Aftemarket caps. I have seen some very good units and some very bad. It all depends on the machining of the surfaces on the bottom of the cap. I also believe it is important to setup your clearances in the upper gear set to get proper lash of the gears. Changing caps can affect this and is an important part of setting up a drive. I would recommend thicker top caps in most all instances. In your case the steering wing plates will have to be moved or redsigned to accomodate new caps. I would start with a call to Latham to see what they offer in this case.
Hope this helps.

Dick

[GLH]

...Usually the L-hand prop turns in a direction to load the torque on the top cap. GLH actually broke the top cap. ...

Broke... Man that thing dun blowed up!!!!

I check everytime I put the plugs in now 35 ft/lbs specially the left one. Not a problem since still on stock cap.

[KAAMA]

I was going to go with an aftermarket billet top cap for my XR's, however I had Mr. Gadgets/Dick measure them with a micrometer and the clearences on the bottom of the caps were way off---these were made by Jack Bailey also known as "Budah". Anyway, they were nice looking pieces and at first he sent me a pair for a standard Bravo One of which I will admit turned out to be very nice---better tolerances than the stock Merc's, but I needed them for the XR's and they ended up being way off and I got tired of waiting, so I just purchased the Merc ITS caps and had Dick machine off the steering bosses to clear my double wing plates. I will attempt to post some pictures of my set-up.

[KAAMA]

Here are a few shots of the set-up on my drives with the Merc ITS style top caps used in conjunction with my MM double wing plates and Simrek "halo" driveshowers.

[KAAMA]

Top view...

[Mr Gadgets]

Someone got their camera to work!!... Nice Pics Mark!!