Reply
 
Thread Tools Search this Thread
 
Old 09 May 2013, 11:47   #1
Member
 
Country: UK - Scotland
Boat name: Wildheart
Make: Humber/Delta Seasafe
Length: 5m +
Engine: Merc 60 Clamshell
MMSI: 235068449
Join Date: Apr 2007
Posts: 4,611
props - Nord-Lock washers?

OK, In summary, I found the prop that came with my engine is either too low a pitch or diameter.

I had been looking for a Merc one at 14", but having had way too many ventilating moments at Easdale where I came to a grinding halt & had to come back to idle & wait a copuple of seconds to get going again, I decided that instead of up -pitching, I would up -diameter instead.


Cutting long stories short, it would appear the Merc props with the "stud hubs" only come in one diameter (well, in the 13 spline version, not sure about the bigger ones) Now, I have what I think might be a suitable Yam prop lying in my garage, (Certainly WRT pitch & diameter), BUT of course it relies on a split pin & castelated nut to stop the nut unwinding, which of course the Merc shaft isn't drilled for as it uses a tab washer.

So,
Option 1 - Drill & tap a couple of holes & put studs on the Yam hub.
Option 2 - Use a "Nord-Lock" washer.

Nord-Lock wedge-locking washers


Anyone used one on a prop? If so how did it fare?
__________________

__________________
9D280 is offline   Reply With Quote
Old 09 May 2013, 11:49   #2
RIBnet admin team
 
Nos4r2's Avatar
 
Country: UK - England
Town: The wilds of Wiltshire
Boat name: WhiteNoise/Dominator
Make: Ballistic 7.8/SR5.4
Length: 7m +
Engine: Opti 225/Yam 85
MMSI: 235090687/235055163
Join Date: Jul 2005
Posts: 12,645
RIBase
Option 3. Use a nyloc?
__________________
Need spares,consoles,consumables,hire,training or even a new boat?

Please click HERE and HERE and support our Trade Members.

Join up as a Trade member or Supporter HERE
Nos4r2 is offline   Reply With Quote
Old 09 May 2013, 12:21   #3
SPR
Trade member
 
SPR's Avatar
 
Country: UK - Scotland
Town: Central Belt of Scotland
Boat name: Puddleduck III
Make: Bombard
Length: 5m +
Engine: 50 HP
Join Date: Mar 2009
Posts: 2,066
Quote:
Originally Posted by Nos4r2 View Post
Option 3. Use a nyloc?
+1 for option 3 - believe some manufacturers use them as standard - down side they are one shot ... and prop need tool to get them off the full way and on...
__________________
SPRmarine / SPRtraining
RYA Training Courses & Safety Equipment Sales
SPR is offline   Reply With Quote
Old 09 May 2013, 12:28   #4
Member
 
Country: USA
Town: Oakland CA
Length: 3m +
Join Date: Feb 2005
Posts: 6,653
Quote:
Originally Posted by SPR View Post
+1 for option 3 - believe some manufacturers use them as standard - down side they are one shot ... and prop need tool to get them off the full way and on...
Deep socket won't do it?

jky
__________________
jyasaki is offline   Reply With Quote
Old 09 May 2013, 13:16   #5
SPR
Trade member
 
SPR's Avatar
 
Country: UK - Scotland
Town: Central Belt of Scotland
Boat name: Puddleduck III
Make: Bombard
Length: 5m +
Engine: 50 HP
Join Date: Mar 2009
Posts: 2,066
Quote:
Originally Posted by jyasaki View Post

Deep socket won't do it?

jky
should do he trick ! just pointing out potential issue!
__________________
SPRmarine / SPRtraining
RYA Training Courses & Safety Equipment Sales
SPR is offline   Reply With Quote
Old 10 May 2013, 04:31   #6
Member
 
Country: UK - Scotland
Boat name: Wildheart
Make: Humber/Delta Seasafe
Length: 5m +
Engine: Merc 60 Clamshell
MMSI: 235068449
Join Date: Apr 2007
Posts: 4,611
Quote:
Originally Posted by Nos4r2 View Post
Option 3. Use a nyloc?
I did toy with that, but as the exhaust is exiting round there when at WOT I'd be curious to know how hot the shaft / nut combo gets, as there should be next to no cooling round them (the cooling water exiting down the leg I would imagine will get thrown out to the perifery like a centrifuge, leaving the shaft & nut in the exhaust that could be at a few hundred C.

I assume the Nylocks used by the manufacturers are high temp rated?


I guess option 4 is Nord Lock with a Nylock on the end of the shft just in case. (TBH if the yam doesn't improve the setup It'll be back to the merc prop anyway!)
__________________
9D280 is offline   Reply With Quote
Old 10 May 2013, 05:37   #7
RIBnet admin team
 
Nos4r2's Avatar
 
Country: UK - England
Town: The wilds of Wiltshire
Boat name: WhiteNoise/Dominator
Make: Ballistic 7.8/SR5.4
Length: 7m +
Engine: Opti 225/Yam 85
MMSI: 235090687/235055163
Join Date: Jul 2005
Posts: 12,645
RIBase
I doubt it actually gets that hot.Rubber prop hubs wouldn't survive long like that.
__________________
Need spares,consoles,consumables,hire,training or even a new boat?

Please click HERE and HERE and support our Trade Members.

Join up as a Trade member or Supporter HERE
Nos4r2 is offline   Reply With Quote
Old 10 May 2013, 07:31   #8
Member
 
Country: UK - Scotland
Boat name: Wildheart
Make: Humber/Delta Seasafe
Length: 5m +
Engine: Merc 60 Clamshell
MMSI: 235068449
Join Date: Apr 2007
Posts: 4,611
True..... but there are numerous grades of rubber out there........

Exhaust gas at the port is going to be around the 8-900 C mark.
Most Nylocks seem to be rated to around 120 Deg C "max". (a few are rated to 175C, but that is likely to add risk to a repair!) Now add vibration etc into the mix, how much further down in temp would you come to feel "safe"?


I've not found any "max continuous temp " data for Nylocks yet.... Watch this space.
__________________
9D280 is offline   Reply With Quote
Old 10 May 2013, 07:43   #9
RIBnet admin team
 
Nos4r2's Avatar
 
Country: UK - England
Town: The wilds of Wiltshire
Boat name: WhiteNoise/Dominator
Make: Ballistic 7.8/SR5.4
Length: 7m +
Engine: Opti 225/Yam 85
MMSI: 235090687/235055163
Join Date: Jul 2005
Posts: 12,645
RIBase
Quote:
Originally Posted by 9D280 View Post
True..... but there are numerous grades of rubber out there........

Exhaust gas at the port is going to be around the 8-900 C mark.
Most Nylocks seem to be rated to around 120 Deg C "max". (a few are rated to 175C, but that is likely to add risk to a repair!) Now add vibration etc into the mix, how much further down in temp would you come to feel "safe"?


I've not found any "max continuous temp " data for Nylocks yet.... Watch this space.
Exhaust gas won't be that hot-it's got cooling water being dumped into it. It'd come out as superheated steam if that was the case.
__________________
Need spares,consoles,consumables,hire,training or even a new boat?

Please click HERE and HERE and support our Trade Members.

Join up as a Trade member or Supporter HERE
Nos4r2 is offline   Reply With Quote
Old 10 May 2013, 08:28   #10
Member
 
Country: UK - Scotland
Boat name: Wildheart
Make: Humber/Delta Seasafe
Length: 5m +
Engine: Merc 60 Clamshell
MMSI: 235068449
Join Date: Apr 2007
Posts: 4,611
Computer failure here - I meant to edit to say "but won't be that hot at the prop"... But tech got in the way.

I do get steam out the idle port, both on the Merc & the old Johnson, but that is mobility closer to the exhaust port.

It max be fine, but at full chat there is approx. 600cc x 5800 of got has being expelled per minute . The cooling water that joins it has already been round the head & warmed up... I am genuinely curios to know how hot it gets round there.

What engines use a single nylok?


Sent from a postage stamp on a 1G connection
__________________

__________________
9D280 is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 21:30.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.