Reply
 
Thread Tools Search this Thread
 
Old 30 August 2015, 18:35   #1
Member
 
Ron Noco's Avatar
 
Country: Ireland
Town: Kerry
Boat name: Independence
Make: FunYak
Length: 4m +
Engine: Honda BF10
Join Date: Jun 2015
Posts: 123
Yamaha F30 overheated :-(

Feck sake, finally got out on a calm day and engine overheated on the way home , wasn't on full throttle either, only 4000 revs when she started smoking out the top exhaust, couldn't Rev it over 1800, turned it off when the pee stream started to become spluttery,

Flushed it out since getting back and it started on the muffs first turn, pee stream strong as always

What do you think happened? Water pump? Or thermostat ?

Help :-(
__________________
Ron Noco is offline   Reply With Quote
Old 30 August 2015, 18:47   #2
Member
 
Country: UK - Scotland
Town: wormit
Boat name: lots of them
Make: various
Length: no boat
Engine: all types
Join Date: Dec 2004
Posts: 632
Impeller key
__________________
Davie is offline   Reply With Quote
Old 30 August 2015, 18:58   #3
Member
 
Country: USA
Town: Oakland CA
Length: 3m +
Join Date: Feb 2005
Posts: 6,653
Kelp or bag blocking the intake?

jky
__________________
jyasaki is offline   Reply With Quote
Old 30 August 2015, 20:47   #4
Member
 
Ron Noco's Avatar
 
Country: Ireland
Town: Kerry
Boat name: Independence
Make: FunYak
Length: 4m +
Engine: Honda BF10
Join Date: Jun 2015
Posts: 123
I took the intake guards off and found nothing, there was a little bit of debris in the pee hole exit, but the pressure is good , if the thermostat doesn't open would that cause the overheating?
__________________
Ron Noco is offline   Reply With Quote
Old 30 August 2015, 21:02   #5
Member
 
Country: UK - England
Length: 3m +
Join Date: Sep 2008
Posts: 2,767
If the thermostat doesn't open yes it would overheat. I'd want the stat out and checked.
__________________
ShinyShoe is offline   Reply With Quote
Old 30 August 2015, 21:07   #6
Member
 
Ron Noco's Avatar
 
Country: Ireland
Town: Kerry
Boat name: Independence
Make: FunYak
Length: 4m +
Engine: Honda BF10
Join Date: Jun 2015
Posts: 123
Ok, when it was getting serviced and a new timing belt the mechanic said he checked the thermostat !
Worse case how will I know if there's damage done?
__________________
Ron Noco is offline   Reply With Quote
Old 30 August 2015, 21:16   #7
RIBnet admin team
 
Poly's Avatar
 
Country: UK - Scotland
Boat name: imposter
Make: FunYak
Length: 3m +
Engine: Tohatsu 30HP
MMSI: 235089819
Join Date: Sep 2005
Posts: 11,632
Davie is a man of few words built on many years experience. I'd follow his pointer first.

As for long term damage compression testing and possibly a boroscope would help, but personally I'd want an expert to look at it.
__________________
Poly is offline   Reply With Quote
Old 30 August 2015, 21:39   #8
Member
 
Country: UK - England
Length: 3m +
Join Date: Sep 2008
Posts: 2,767
Sorry just though - you tested on Muffs. I've never used muffs. Would there be water flow even if the impeller failed? If so then water flow means nothing.

Testing in a bucket would confirm that as if the paddles on the impeller are missing or the key has failed and the paddles are just spinning freely. BUT testing in a bucket with failure would result in potentially more damage...

Your mechanic who checked the thermostat presumably also checked the impeller?
__________________
ShinyShoe is offline   Reply With Quote
Old 30 August 2015, 22:01   #9
Member
 
Ron Noco's Avatar
 
Country: Ireland
Town: Kerry
Boat name: Independence
Make: FunYak
Length: 4m +
Engine: Honda BF10
Join Date: Jun 2015
Posts: 123
I'll take off the lower unit tomorrow and see what the story is...

No confidence in the mechanic or the guy running the dealership

Looks like it's not my year , off the water for awhile :-(
__________________
Ron Noco is offline   Reply With Quote
Old 30 August 2015, 22:43   #10
Member
 
Country: UK - England
Town: Leicester
Length: 5m +
Engine: 135hp Mercury
Join Date: Sep 2013
Posts: 1,431
Quote:
Originally Posted by ShinyShoe View Post
Sorry just though - you tested on Muffs. I've never used muffs. Would there be water flow even if the impeller failed? If so then water flow means nothing.

Testing in a bucket would confirm that as if the paddles on the impeller are missing or the key has failed and the paddles are just spinning freely. BUT testing in a bucket with failure would result in potentially more damage...

Your mechanic who checked the thermostat presumably also checked the impeller?
My Mercury doesn't put water out of the tell-tale with just a hosepipe connected to the muffs unless the engine's running. Turn the engine off & the telltale stops.
Check the stat.
__________________
paintman is offline   Reply With Quote
Old 30 August 2015, 23:04   #11
Member
 
Country: UK - England
Length: 3m +
Join Date: Sep 2008
Posts: 2,767
Quote:
Originally Posted by paintman View Post
My Mercury doesn't put water out of the tell-tale with just a hosepipe connected to the muffs unless the engine's running. Turn the engine off & the telltale stops.
Check the stat.
Yeh - but your impeller would stop the flow as its not turning. But if the impeller is damaged water can flow past, or if the key is damaged it can spin on its spindle.
__________________
ShinyShoe is offline   Reply With Quote
Old 30 August 2015, 23:54   #12
Member
 
Country: UK - England
Town: Leicester
Length: 5m +
Engine: 135hp Mercury
Join Date: Sep 2013
Posts: 1,431
The impeller would act as a plug.
If the key is damaged/missing the pump drive shaft will be turned by the engine but not pump water as the impeller isn't turning & blocking the water supply so I doubt if you'd get any water from the telltale.
If there was no impeller in place or a number of its blades are badly damaged or broken then I expect it could be possible for water to reach the top of the engine on muffs when not running.

Be interesting to see what would happen with the OPs if run in a bucket. Or what he finds when he drops the gearbox to check the impeller & key.
__________________
paintman is offline   Reply With Quote
Old 31 August 2015, 08:58   #13
Member
 
Country: UK - England
Length: 3m +
Join Date: Sep 2008
Posts: 2,767
If the key is missing /broke ... Why would putting water in the intake at pressure (I.e muffs) not just spin the impeller on the shaft and allow water past?
__________________
ShinyShoe is offline   Reply With Quote
Old 31 August 2015, 09:13   #14
Member
 
Country: UK - Scotland
Town: wormit
Boat name: lots of them
Make: various
Length: no boat
Engine: all types
Join Date: Dec 2004
Posts: 632
Dont know why but I have had 3x F30/40 keys shear this year I have never seen a key snap for years. They seem to wedge in at idle but lose drive anything over 1500 rpm.
__________________
Davie is offline   Reply With Quote
Old 31 August 2015, 09:17   #15
Member
 
Country: UK - England
Town: Leicester
Length: 5m +
Engine: 135hp Mercury
Join Date: Sep 2013
Posts: 1,431
Going on my own engine & its impeller I'd be very surprised if domestic water pressure could turn the impeller. The blades are very curved when in position.
Plus the muff cups are flexible to allow them to conform as well as possible to the water intake & consequently don't form a waterproof seal in the way that a screw in adapter would, water can escape round the edges. I use the muffs for flushing only as per the instructions in the manual. If I want to run for extended periods or at higher revs then I use a cut-in-half plastic 55 gallon drum.
__________________
paintman is offline   Reply With Quote
Old 31 August 2015, 09:18   #16
Member
 
Country: UK - England
Town: Leicester
Length: 5m +
Engine: 135hp Mercury
Join Date: Sep 2013
Posts: 1,431
Quote:
Originally Posted by Davie View Post
Dont know why but I have had 3x F30/40 keys shear this year I have never seen a key snap for years. They seem to wedge in at idle but lose drive anything over 1500 rpm.
Bad batch?
__________________
paintman is offline   Reply With Quote
Old 31 August 2015, 11:26   #17
Member
 
Country: UK - Scotland
Town: wormit
Boat name: lots of them
Make: various
Length: no boat
Engine: all types
Join Date: Dec 2004
Posts: 632
Quote:
Originally Posted by paintman View Post
Bad batch?
All on pre fuel injection
__________________
Davie is offline   Reply With Quote
Old 31 August 2015, 12:55   #18
Member
 
Country: UK - England
Town: Retford
Boat name: Spy-sea-one
Make: Excel 435
Length: 4m +
Engine: Suzuki Outboard/25/4
Join Date: Oct 2011
Posts: 7,532
RIBase
The impeller is larger than the pump housing that's why you have to rotate in the direction of the shaft so the vanes lean back hence the resistance caused will prevent tap pressure spinning the impeller unless it's completely shot then the bits of rubber go up the waterways had it happen to one at work resulting in overheating if the engine has stood a while with an old impeller it could have work hardened and broke up best to strip the leg off have a look. Look on you-tube for D-Rays shop impeller service.
Cheers.
__________________
jeffstevens763@g is offline   Reply With Quote
Old 31 August 2015, 21:32   #19
Member
 
Ron Noco's Avatar
 
Country: Ireland
Town: Kerry
Boat name: Independence
Make: FunYak
Length: 4m +
Engine: Honda BF10
Join Date: Jun 2015
Posts: 123
Pictures tell a thousand words as the saying goes....

Click image for larger version

Name:	ImageUploadedByRIB Net1441052651.565872.jpg
Views:	195
Size:	30.3 KB
ID:	108286

Click image for larger version

Name:	ImageUploadedByRIB Net1441052688.665488.jpg
Views:	211
Size:	31.3 KB
ID:	108287

Click image for larger version

Name:	ImageUploadedByRIB Net1441052716.161002.jpg
Views:	220
Size:	65.4 KB
ID:	108288

Mechanic said he checked the thermostat and it was fine, don't know wtf he checked but it certainly wasn't fine!
Don't have a kicker engine yet but because the engine was freshly serviced by my local Yamaha dealer and had a new timing belt, I felt I'd be safe enough to take the kids for a quick spin, after it overheated it took me over an hour rowing to get back, fairly pissed off now... :-(
__________________
Ron Noco is offline   Reply With Quote
Old 31 August 2015, 22:39   #20
Member
 
1eyedjim's Avatar
 
Country: UK - England
Town: Birmingham
Boat name: Sparrowhawk
Make: Osprey
Length: 5m +
Engine: Yamaha 90hp 2T
Join Date: Apr 2010
Posts: 215
Send him the picture asking what he actually checked
__________________
1eyedjim is offline   Reply With Quote
Reply


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




All times are GMT. The time now is 07:36.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.