Author Topic: Hurth Transmission  (Read 1299 times)

Offline deisher6

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Re: Hurth Transmission
« Reply #30 on: February 28, 2017, 11:09:32 AM »
OK!  I sailed and very tentatively motored Windrunner up to Potters Marine on the Pamlico. A very peaceful marina, $5/day, and convenient to Capt'n Smith.  Other than the $5/day the best deal was being convenient to the mechanic.

What I had Done: 1) replaced motor mounts, 2) replace transmission, 3) replaced drive or thrust plate, 4)replaced prop shaft collar, 5) align the engine and shaft and 6) though not planned replaced the 45° galvanized fitting on the exhaust.

Cost:  Parts $1803,  Labor $800,  misc $225  really close to 3 Boat Units.

Capt'n Smith took one look at the transmission and said that I had the wrong shifter bracket.  I ordered the horizontal shifter bracket.  Two days later when the bracket arrived, Capt'n Smith was back and pulled the transmission.  He then noted that I had the wrong drive plate.  He took the transmission with housing to his shop.  He sald that he had to grind just a little on the housing to get the transmission to fit. Three days later when the correct drive plate arrived, he installed the transmission, motor mounts, aligned the shaft and adjusted the shifter throw.  I spent the rest of the day connecting the exhaust and heat exchanger.

Notes:  1) Replaced old hoses on heat exchanger.  2) The heat exchanger has to be removed from its bracket and lifted up to check the oil and fill the transmission.  I have done this not as hard as it sounds about a 15 minute job.  3) I am not sure why the 45° fitting was in the exhaust.  I checked out Wes's C-27 and replaced the fitting with hose just like his was plummed.  3)  Replaced the pencil zinc in the heat exchanger while it was easy to get to.

Problems:  On engine start up, all was well, until shifted into gear.  Not noticeable at first in forward there was a distinct whine in reverse.  The whine increased with rpm in reverse and was noticeable in forward at higher rpm.  Capt'n Smith checked it out at length using a mechanics stethoscope and also checked the shifter adjustment.  His opinion was that the sound was comping from some source aft of the transmission.  Sound Marine, Joe, wanted a credible mechanic to verify the installation.  Capt'n Smith has an overabundance of credibility in the Pamlico area.  However, I motored the boat 22nm up to Washington and had another mechanic, who Joe recommended check the installation.  Same diagnosis.

Finally:  The shift cable is about a foot to long for the new transmission.  It has a large loop in it that runs between the fuel tank and water heater.   While returning to New Bern I noticed that i could change the nature of the whine by tweaking the shift lever.  I suspect that there might be to much friction in the cable to allow the shift detents in the transmission to work properly.  I am going to cut a groove in the plywood between the fuel tank and hot water heater to allow for a larger diameter loop in the cable, and eventually order a shorter cable.

Hope that this helps someone!

regards charlie
« Last Edit: March 01, 2017, 06:09:11 PM by deisher6 »

Offline deisher6

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Re: Hurth Transmission
« Reply #31 on: February 28, 2017, 11:14:51 AM »
Some flicks:
New exhaust set up and heat exchanger problem with checking oil in transmission.
« Last Edit: February 28, 2017, 11:19:39 AM by deisher6 »

Offline deisher6

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Re: Hurth Transmission
« Reply #32 on: February 28, 2017, 11:18:45 AM »
More flicks:
Old exhaust and pencil zinc in heat exchanger.
« Last Edit: February 28, 2017, 11:20:23 AM by deisher6 »

Offline deisher6

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Re: Hurth Transmission
« Reply #33 on: March 29, 2017, 02:37:43 PM »
This will be my last post on this thread.  (Hopefully !!!)

I just installed a new Edison 6ft clutch cable.  Edison sells their cables in 2ft increments.   I measured 80in for the cable and ordered a 6ft cable on a prayer, $80 with S&H.  Wes says that Hamilton Marine sells in 1 ft increments.  Fortunately the Edison cable fit like a glove (for the port shifting transmission).  The old cable was 8ft Morse.  I do not know if it was original.

The new cable has 90% less drag and allows feeling the transmission indexes for the Fwd, Neutral and Rev positions. 
--Edison sells or will give pedestal decals.  Needed since shifting is reversed.
--the whine is less noticeable.  I am going to attribute much of it to new sounds.  Especially since the motor is quieter with new mounts.

Lastly when I rebuilt the pedestal and replaced the binnacle compass I added a cover that I thought would protect the sprocket and cables from water.  When I dissembled the pedestal to install the cable the cover had been broken by the shifter lever.  There was not enough clearance for Fwd.  I do not know if this started or added to the transmission problem by not allowing the transmission to fully engage in Fwd.  However it could not have been good.

Time to go sailing.

regards charlie