Mercury 9.8HP (110)

Ribtecer · 21 June 2010, 18:44

Hi Fellas

Aside to my Rib I have a Sib (Avon Rover 310) that I really only use once a year at a sailing week for kids as one of the safety boats, on my sib I have an elderly but excellent Mercury 9.8HP.

I have just got the engine out to start it up ready for this year, it started up fine no problem but the tail tell was weak, this engine has a thermostatically controlled flow and when I took the thermostat out underneath it was big lumps of salt crystals, now I always run the engine in a wheelie bin after use and run it for sometime.

I removed all the salt I could see and replaced the housing without the thermostat, I took the engine out of the water and sprayed silicon grease up the water in take and started her up with a bucket under the tail tell, water pi$$ed out along with all sorts of crud and then came the silicon grease. Now my question is, now it is relatively clear of salt and is peeing nicely should I just leave the thermostat out permanently?

I know it will be slightly less efficient, but it will still work and what little extra damage to the environment would be a lot less than manufacturing a new outboard and then shipping said outboard from the Far East to me here in England only to use it for just one week a year.

What does the panel think?

uncle al · 22 June 2010, 08:18

Quote:

Originally Posted by Ribtecer

Hi Fellas

Aside to my Rib I have a Sib (Avon Rover 310) that I really only use once a year at a sailing week for kids as one of the safety boats, on my sib I have an elderly but excellent Mercury 9.8HP.

I have just got the engine out to start it up ready for this year, it started up fine no problem but the tail tell was weak, this engine has a thermostatically controlled flow and when I took the thermostat out underneath it was big lumps of salt crystals, now I always run the engine in a wheelie bin after use and run it for sometime.

I removed all the salt I could see and replaced the housing without the thermostat, I took the engine out of the water and sprayed silicon grease up the water in take and started her up with a bucket under the tail tell, water pi$$ed out along with all sorts of crud and then came the silicon grease. Now my question is, now it is relatively clear of salt and is peeing nicely should I just leave the thermostat out permanently?

I know it will be slightly less efficient, but it will still work and what little extra damage to the environment would be a lot less than manufacturing a new outboard and then shipping said outboard from the Far East to me here in England only to use it for just one week a year.

What does the panel think?

NO dont leave the thermostat out they are fitted for a reason your engine will run colder than it should

Ribtecer · 22 June 2010, 11:11

Quote:

Originally Posted by uncle al

NO dont leave the thermostat out they are fitted for a reason your engine will run colder than it should

Thank you for your reply, what damage can occur by it running colder?

uncle al · 22 June 2010, 13:53

you might have to run it on choke longer which will wash moving parts, increase fuel consumption, run dirtyer because of the extra fuel burnt ,there is a chance that all the fuel wont be burnt but blown out through the exhaust

Ribtecer · 25 July 2010, 12:52

Any ideas how easy it would be to get a new themostat for this engine, or would anyone know the part number?

Thank you

uncle al · 26 July 2010, 09:25

morning
if you could ring me on 01869 326411 with your obm serial number ,but i think the part number for a thermostat is 75692 but to be sure i require a s/n, they can be purchased from any merc/mar dealer you will also require
1X 27-88346 gasket
1X 27-62386001 gasket
regards
uncle al

uncle al · 26 July 2010, 18:12

i put that badly you can purchas the thermostats from dealers not serial numbers old age is dreadfull so dont try it

Locozodiac · 26 July 2010, 23:01

Quote:

Originally Posted by Ribtecer

Any ideas how easy it would be to get a new themostat for this engine, or would anyone know the part number?

Thank you

Why do you need to change the thermostat for ? If only salty stuck, you can soak it in pure vinegar for 15 minutes and brush away with an old teeth brush. Perform the function test: 1-Suspend thermostat and thermometer in a heat resistant container pyrex type filled with water 2-Slowly heat and stirr the water, verify thermostat opens at 140º F, 60º C. If it doesn't open at specified temp, replace thermostat. 3-Remove thermo and place on table, verify it's closing action as it cools down, if it's not slow and smooth replace it. If still working properly put it back on, there is also a water pressure issue on engine head when using engine with thermostat removed.

Downhilldai · 26 July 2010, 23:34

Quote:

Originally Posted by uncle al

old age is dreadfull so dont try it

Got to be better than the alternative though, eh al?

Ribtecer · 27 July 2010, 23:59

Thanks Guys.

Ribtecer · 04 August 2010, 18:48

Quote:

Originally Posted by uncle al

morning
if you could ring me on 01869 326411 with your obm serial number ,but i think the part number for a thermostat is 75692 but to be sure i require a s/n, they can be purchased from any merc/mar dealer you will also require
1X 27-88346 gasket
1X 27-62386001 gasket
regards
uncle al

Two amazing things;

1. Your knowledge to know that it is a 75692 thermostat
2. In a big box of old boat bits I acquired there was a 75692 in its packaging, which did not come with the engine – really amazing - my father always said never throw anything away, and unfortunately for my wife I listened.

Thing is the packaging states that it in fact it is a 75692Q03 is this the same product?

And the serial number of my engine is 9250430

Thanks again for all your help Uncle Al.

Toby

T 15 · 04 August 2010, 19:56

Quote:

Originally Posted by Ribtecer

Two amazing things;

1. Your knowledge to know that it is a 75692 thermostat
2. In a big box of old boat bits I acquired there was a 75692 in its packaging, which did not come with the engine – really amazing - my father always said never throw anything away, and unfortunately for my wife I listened.

Thing is the packaging states that it in fact it is a 75692Q03 is this the same product?

And the serial number of my engine is 9250430

Thanks again for all your help Uncle Al.

Toby

sorry, cant help re the product No.

re your serial No. ; I am getting a contradiction from my year lists, looks as if it is either 1978 or 1980/81, ( built in Belgium ), can you post a photo of the engines decals ? ( I assume they are the original decals )

added:

looks as if the 9.8hp 110 was last built in 1978, from 1979 the 9.8 was 9.8, so it looks as if it may be 1978

Ribtecer · 04 August 2010, 20:33

Yes it has built in Belgium written on it.

Re pictures, will do and post tomorrow.

Thank you for your speedy reply.

Toby

uncle al · 05 August 2010, 06:53

i work in customer service for the U.K.distributer and have a parts disc for the brunswick products and access to information that is not in the public domain, (ok dealers that know me STOP laughing) and 48yrs experiance of engines

uncle al · 05 August 2010, 08:38

hi
I have checked and 75692q03 is a differant thermostat ,what it is fitted to i dont know as it is a superseaded number that hasnt caught up with the epc all other p/ns are good
uncle al (alan)

johno · 27 April 2011, 21:14

Hi Al,
I am in Buckingham can you recomend service shop for Merc 9.8 110?.
Thanks John 01296713152