So, I pulled the DP-S drive on my new used boat to check it out during winterization.
The U joints were making a bit of noise.
Volvo is very specific in their shop manual that you must use genuine, high quality Volvo parts or you will go to Volvo hell.
So, I take the thing abpar and inspect the u joints.
First thing I notice is they say "Made in Singapore" a well known bastion of high quality stuff(?).
Turns out the rollers in the joint were just fine but the ends of the trunnions were worn by nearly .050" allowing the spider to slide back and forth on each revolution making a clicking sound.
Now for replacements.
Not wanting some more genuine "Made in Singapore" parts I did some homework.
The dimensions of the joints are identical to a readily available Spicer part.
Volvo wanted big dollars, the "Made in USA" Spicers were $16 each.
Primary difference to the eye is the Spicers have more but smaller rollers.
Fortunantly, I have a good friend who is the head of powertrain engineering at GM.
His take on the difference is that the bigger rollers in the Volvo part will take a higher shock load but the smaller rollers will have a longer life.
Two points
First, the shock load on a boat is not even in the same league as a 4wd dancing over rocks or a car that is slammed from reverse to forward at speed.
Second, a stock small block in a boat doesn't stress the u joints at a fraction of their design.
The Spicer part is in their catalog as a part supplied to Mercruiser.
I disassembled the bearings, cleaned them thoroughly and relubed them with Amsoil synthetic race grease.
It took a bit of time but I have more of that than money.
Genuine Volvo parts my kapootie.
Maybe, if I was running a supercharged big block, I would want joints with the larger rollers to take the shock load when I came out of the water at 100mph.
But, I sure wouldn't want the "made in Singapore" things that do not even have grease channels in the ends of the caps!
The U joints were making a bit of noise.
Volvo is very specific in their shop manual that you must use genuine, high quality Volvo parts or you will go to Volvo hell.
So, I take the thing abpar and inspect the u joints.
First thing I notice is they say "Made in Singapore" a well known bastion of high quality stuff(?).
Turns out the rollers in the joint were just fine but the ends of the trunnions were worn by nearly .050" allowing the spider to slide back and forth on each revolution making a clicking sound.
Now for replacements.
Not wanting some more genuine "Made in Singapore" parts I did some homework.
The dimensions of the joints are identical to a readily available Spicer part.
Volvo wanted big dollars, the "Made in USA" Spicers were $16 each.
Primary difference to the eye is the Spicers have more but smaller rollers.
Fortunantly, I have a good friend who is the head of powertrain engineering at GM.
His take on the difference is that the bigger rollers in the Volvo part will take a higher shock load but the smaller rollers will have a longer life.
Two points
First, the shock load on a boat is not even in the same league as a 4wd dancing over rocks or a car that is slammed from reverse to forward at speed.
Second, a stock small block in a boat doesn't stress the u joints at a fraction of their design.
The Spicer part is in their catalog as a part supplied to Mercruiser.
I disassembled the bearings, cleaned them thoroughly and relubed them with Amsoil synthetic race grease.
It took a bit of time but I have more of that than money.
Genuine Volvo parts my kapootie.
Maybe, if I was running a supercharged big block, I would want joints with the larger rollers to take the shock load when I came out of the water at 100mph.
But, I sure wouldn't want the "made in Singapore" things that do not even have grease channels in the ends of the caps!
