trs rotation?
06-26-2009 | 03:44 PM
#11
Frank's Marine Service
Joined: Sep 2002
Posts: 11,959
Likes: 142
From: Elkton, MD
I always heard the RH drives were stronger than the LH. In the LH the drive shaft is end to end turning the prop shaft which would create more bind on the propeller end,more twisting load. RH turns the prop shaft from the center of the shaft so the support is evened out on both ends of the propeller shaft.
In rough water and high HP applications the torque trys to separate the gears and on the RH drives the carrier moves because there's a crush collar between the spanner nut and the carrier and it can flex and skew the gear lash, resulting in gear failure.
06-26-2009 | 05:23 PM
#12
Offshoreonly Advertiser
Joined: Mar 2001
Posts: 2,517
Likes: 280
From: Pompano Beach FL, USA
Panther - not exactly true. The crush (load ring) is actually at the forward end of the carrier. The load to the rear is 100% carried by the spanner nut. There is nothing pushing the carrier forward. I will agree on the RH drive the gear load is trying to push the carrier out.
If the housing is corroded/stripped it can pop the nut out - carrier, shaft, prop and all.
The LH drive has the gear forward against the bullet so you won't pop the carrier out so it is stronger in that respect.
In either direction I think the prop shaft is stout enough so deflection & twist are not an issue.
Actually I've been doing this since the TRS came out and I don't remember there being an pattern as to which is more likely to fail except for the housing issue.
If the housing is corroded/stripped it can pop the nut out - carrier, shaft, prop and all.
The LH drive has the gear forward against the bullet so you won't pop the carrier out so it is stronger in that respect.
In either direction I think the prop shaft is stout enough so deflection & twist are not an issue.
Actually I've been doing this since the TRS came out and I don't remember there being an pattern as to which is more likely to fail except for the housing issue.
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Marc
www.mercruiserparts.com
www.go-fast.com
www.bammarine.com
www.cyborgtransmissions.com
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Last edited by Mbam; 06-26-2009 at 11:40 PM.
06-27-2009 | 08:48 AM
#14
Frank's Marine Service
Joined: Sep 2002
Posts: 11,959
Likes: 142
From: Elkton, MD
Panther - not exactly true. The crush (load ring) is actually at the forward end of the carrier. The load to the rear is 100% carried by the spanner nut. There is nothing pushing the carrier forward. I will agree on the RH drive the gear load is trying to push the carrier out.
If the housing is corroded/stripped it can pop the nut out - carrier, shaft, prop and all.
The LH drive has the gear forward against the bullet so you won't pop the carrier out so it is stronger in that respect.
In either direction I think the prop shaft is stout enough so deflection & twist are not an issue.
Actually I've been doing this since the TRS came out and I don't remember there being an pattern as to which is more likely to fail except for the housing issue.
If the housing is corroded/stripped it can pop the nut out - carrier, shaft, prop and all.
The LH drive has the gear forward against the bullet so you won't pop the carrier out so it is stronger in that respect.
In either direction I think the prop shaft is stout enough so deflection & twist are not an issue.
Actually I've been doing this since the TRS came out and I don't remember there being an pattern as to which is more likely to fail except for the housing issue.
My personal experience breaking a few TRS's was 1 LH and 3 RH's and once I solid shimmed it I didn't break any more RH's for a long time and then I sold the boat. Overall I still liked the drive though!
06-27-2009 | 09:24 AM
#15
Registered
Joined: Aug 2007
Posts: 2,960
Likes: 7
From: Sandown, NH - Sebago Lake Region, ME
Yes, it is a 1978/ 20 footer with a stroked small block, 383 with all the goodies, hits 70 plus. Purchased as a project and re-powered it, drive got stolen last summer and i replaced this summer. This was a 3 year project , was an interesting learning curve and its a hit on the lake being piloted by a women. lol.
Also the answers I got here were very helpful in buying a replacement that worked. I thank everyone who posted on this topic.
maxine
http://images.ibsrv.net/ibsrv/res/sr...coolcowboy.gif
Also the answers I got here were very helpful in buying a replacement that worked. I thank everyone who posted on this topic.
maxine
http://images.ibsrv.net/ibsrv/res/sr...coolcowboy.gif
07-13-2009 | 07:30 AM
#17
Registered
Joined: Mar 2006
Posts: 432
Likes: 0
From: Lake George NY
One of the problems with TRS gear failure is people are running high HP and speeds the lower unit is comming up and out of the water and they are like suface riding the drive. The TRS only has one vertical shaft and was not desighned to be run that way. The vertical shaft starts to whobble and its all down hill from there.
07-14-2009 | 04:06 PM
#18
Registered
Joined: Nov 2003
Posts: 190
Likes: 2
From: Annapolis, Md
One of the problems with TRS gear failure is people are running high HP and speeds the lower unit is comming up and out of the water and they are like suface riding the drive. The TRS only has one vertical shaft and was not desighned to be run that way. The vertical shaft starts to whobble and its all down hill from there.
I think they are great pieces of "farm equipment" for "plowing along".........
