justdreamin

Can't remember the gear ratio right off the top of my head.. but i will check tomorrow. I have also got some confusing replies from rik. He told me they were asd6's in another forum.. I will look for the link. I also emailed several times about the price on an aft retaining ring for one of the drives. Its missing a few teeth that the wrench engages in but does not affect anything as far as how they perform and I have explained it to anyone who has called. I think I may still have some of the emails about these drives. I was looking to put them on another boat I have but the transom is notched and it would be a lot of work to change it over.... Atleast that is what I am told. From everything I have read Arneson drives are one of the most reliable drives with low maintence. However Its like pulling teeth to get answers. I decided to stick with the TRS for now. I was going to use the scarab as a donor boat but now that I am not going to use the drives I hate to start stripping the boat down when this would make a sweet boat when someone is finished. I will look for the emails..

justdreamin

straight out of an email from Jan. If you are interested.

The in line ASD6 drive units are not usable unless:

1. You have a diesel application that has a transmission to handle the RH and LH rotation as well as the reduction

2. You use a "V Drive" inside the boat whereby it has your drop, reduction and rotation built into it.


and later in the email

As I stated in your yellow highlight, the only use (which they were designed for) for the in line drives is for diesel applications. You can make a V-Drive work (you should look them up to see how they function and you will understand) but it has its drawbacks too. This is why I mentioned the ASD6 drop box drives.

Rik

justdreamin

Alright... Straight off the trans ID Plate..

"Model MG502
Ratio 1.54:1
Manufactured By
Twin Disc International S.A.
B1400 Nivelles Belgium"

The boat Has 17x28 props and the guy said it had 454 blower motors and ran 110... before he blew up the port side engine. Can't remember if he even told me hp... At the time all i could think about was putting those drives. on my boat.

justdreamin

This is the boat i was going to use them on and decided not to... would of ran into a lot of problems trying to get it right

justdreamin

To be honest with you I have read the thread you posted about 1720's and 1721's a while back and you guys have me royally confused.... All I know is rik commented on one of my post which I will find shortly and commented on some emails and told me for sure they are asd6's and you have a lot more knowledge about these drives than me and you say they are 1720's.. I advertised them based off what rik told me... And I have seen half a dozen on craigslist or craiglook... (which ever you use) in the last six months and they look exactly like this. There are no Markings on the drives other than the casting that says arneson. rik said asd6's

Rik

As I told you on the phone. If the aft retaining ring is a screw in type, not a spiral lock, they are ASD6's.

tomuchstuff

Rick did'nt you say it was if the thrust ball bolts on to the thrust tube its asd6 or 1721? and if the thrust ball screws on it 1720?

that 1721 and asd 6 are a little larger where the ball bolts to the tube on the newer models...

if not then there is know way of knowing what you have if all you have is a thrust tube?

tomuchstuff

Wow that's not going to work like that... you'd need to cut a half circle in that step to just below the O/D hole and glass it back to the inset part of the transom where it meets the bottom... I don't know if your engine and trany will fit in that engine bay if you went and did it that way so i'd be test fitting the engine first, it'd be the place to start.. in truth u'd be better extending the bottom to the transom or making the step an inch or two above the bottom and you'll end up with more engine room in the right place for you trany... I think you'd need do to this to run a drop box or any thing but o/b or o/d but who knows..

was it a vdrive? was that what was in that arneson boat? its hard to get the proper drive line angle for inline so some boat ran a v drive...

ho hi was the drive from the bottom of the transom on the boat the drives were pulled from?
are your thrust tubes brass or aluminum?
is the thrust tube marked borg warner any where?
how old is that boat?

from what I read borg warner only made an aluminum 1720 1721 and asd6 and all otheres were made by arneson at his shop... then twin disk bought both arneson and arneson borg warner and made all the drives... be for 83 there was no drop box and after 83 the inline housing changed and the 1721 and asd6's were both inline or drop box.... arneson used the 1720 to race till around 83 in line when he came up with the 16" 1600 drop box.. I did read that he put a c/v in some of the 1720 race drives!!!!! back then and that the h joint was the week link... and in larger arneson drives the stronger joint was still used..

you may have some howard arneson race drives! if there brass, if there not marked B/W and if there pre 83 1720's .. pull them a part check that joint.....

justdreamin

They are Brass. And they are not marked anywhere... That is when I started sending pictures to rik. I started cleaning one up trying to find numbers anywhere and could not... I would pull them apart but do not have the wrench for the aft retaining ring. Do you have one? and what do you want for it.

justdreamin

They are screw in type.