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Part # 18-3540
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Part # 18-3541
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Part # 18-3608
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Part # 18-3609
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Part # 18-3611
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Part # 18-3608D
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Discontinued
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Part # 18-0754
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Part # 18-3622
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Thermostat Gasket - 18-60508 - Sierra
Price: $3.20
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Sierra
Mallory and Sierra Thermostats for Yamaha outboard engines.
Average Customer Review for Sierra 18-3540 Yamaha Thermostat
Full StarFull StarFull StarFull StarEmpty Star
Based On 6 Reviews | Write Review
Full StarFull StarFull StarFull StarFull Star
Worked perfect
by Frank s from San Manuel, Arizona on September 23, 2016
Wasn't sure if it was right one but fit perfect and they answered my question . great product
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Full StarFull StarFull StarFull StarFull Star
Tstats
by Edward from Washington, North Carolina on September 07, 2016
Nice, Shiney, new! Works as supposed to. Fast shipping great customer service. I buy 90% of my parts from iboats, much cheaper than purchasing locally.
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Full StarFull StarFull StarFull StarFull Star
Fits just right
by Bruce from Plant City, Florida on June 16, 2016
Appears to be exactly what I need
(1 of 1 people found this review helpful)
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Full StarFull StarFull StarFull StarFull Star
Thermostat for a 150 Hp Yamaha
by Brad from Orange, Texas on May 17, 2016
Part is exactly what I needed. A perfect fit!
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Full StarFull StarFull StarFull StarFull Star
Good product. Good price.
by Robin from Newton, North Carolina on November 08, 2014
New thermostats worked great.
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Full StarEmpty StarEmpty StarEmpty StarEmpty Star
Wrong thermostat was shipped
by Paul from Friendswood, Texas on November 14, 2013
I ordered the Thermostat - Sierra Part # 18-3540. Two issues. 1)This thermostat was not compatible with my outboard Yamaha 115HP 2-stroke 2)The thermostats that were shipped to my address was not identical to the picture of the part Thermostat - Sierra Part # 18-3540 listed with the web site. I Will return to part to iboats soon.
(1 of 1 people found this review helpful)
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Average Customer Review for Thermostat Kit - 18-3608 - Sierra
Full StarFull StarEmpty StarEmpty StarEmpty Star
Based On 1 Review | Write Review
Full StarFull StarEmpty StarEmpty StarEmpty Star
Thermostat Kit 18-3608
by Timothy from Hilton Head Island, South Carolina on April 24, 2017
Ordered 2 new kits for my boat, received order promptly as advertised but one kit contained the wrong thermostat, which I'm not sure how as it was labeled as 18-3608 in sealed package. The package did appear to be older and worn compared with the correct kit packaging. Either way, still waiting for the arrival of the correct thermostat. The correct thermostat and gasket appear to be exact same as the product I'm replacing, hopefully they'll perform to the motor standards.
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Average Customer Review for Sierra 18-3609 Thermostat Kit
Full StarFull StarFull StarFull StarFull Star
Based On 1 Review | Write Review
Full StarFull StarFull StarFull StarFull Star
Fast service and shipping
by Irvin from Deltona, Florida on December 08, 2016
Got no complaints here got my part fast no hassle no problems. Will use Iboat again.
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Average Customer Review for Sierra 18-3608D Thermostat Kit Yamaha
Full StarFull StarFull StarFull StarFull Star
Based On 2 Reviews | Write Review
Full StarFull StarFull StarFull StarFull Star
Typical Sierra quality
by Bruce from Plant City, Florida on June 16, 2016
Haven't installed yet, but parts are all high quality,
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Full StarFull StarFull StarFull StarFull Star
Both pieces look to be as good as oem
by Bruce from Plant City, Florida on June 16, 2016
Can't beat the price and service from iboats. Had a delay in the order shipping out on schedule due to availability of one item. Kudos to customer service for resolving with a workaround and getting the parts delivered promptly.
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Average Customer Review for Sierra 18-3622 Thermostat Kit
Full StarFull StarFull StarFull StarFull Star
Based On 1 Review | Write Review
Full StarFull StarFull StarFull StarFull Star
Perfect Match
by Brian from Jupiter, Florida on October 02, 2012
Part came in ontime and in good condition. Engine cooling is working now
(2 of 2 people found this review helpful)
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Q:
Will the thermostat and gasket fit my VX 150TLRZ 2001?
A:
No it will not, you will need 18-3608.


Q:
Will this fit my 2001 yamaha 40 hp 2 stroke ?
A:
Yes, this is a standard kit for your Yamaha application.


Q:
Will this fit a 1987 yamaha 30hp 3 cyl?
A:
Yes this will fit your engine.


Q:
Will this fit a 2007 60 hp?
A:
No you will need 18-3541.


Q:
Will this fit pro v 150 h outboard, and if yes, what's the # for the gaskets?
A:
We will actually need the engine model number or at least the exact year for your application to match up correct parts.


Q:
Will this fit 1987 pro v 150 h 6j9 L, ser?
A:
Yes this thermostat will work for your motor.


Q:
Will this fit my 2004 200hp 2 stroke?
A:
Yes this will work for your motor.


Q:
Will it fit 1985 50hp 2 stroke?
A:
No it will not. You will need OEM part number 688-12411-11-00.


Q:
What is right thermostat for 1990 yamaha F9.9 6G8 L 466372?
A:
You will need part number 18-3541.


Q:
Will this fit a 2005 f225?
A:
No it will not. You need 18-3632.


Q:
Will this work on 2002 Yamaha 115 4 Stroke?
A:
Yes, this is the standard replacement for your Yamaha engine.


Q:
Is this the proper thermostat for 2003 Yamaha 250 hpdi?
A:
It depends on your model number. Different models call for different thermostats. Best thing to do is call us with your model number and we can take a look. 1-800-914-1123.


Q:
What is proper thermostat for my yamaha 1998 150 salt water series II?
A:
This thermostat will work for your application.


Q:
Wil this Thermostat fit the 2002 Yahama 150TXRA?
A:
Yes this will fit your motor.


Q:
Will this one fit my 1999 200hp sal er II S200TXRX?
A:
Yes this will work for your engine.


Q:
Will this fit a sx 250 txra yamaha?
A:
Yes, this does go to a SX250 year 200-2002.


Q:
Are there 2 in pack?
A:
It is sold individually.


Q:
2002 yamaha sx200txra is this the thermostat i need?
A:
Yes this is the thermostat for your engine.


Q:
Will this fit my 2001 Yamaha 115 4 stroke outboard?
A:
No this will not. You will need 18-3525.


Q:
Are the thermostat gaskets with these thermostats or must be purchased seperately?
A:
This is just the thermostat. Gaskets must be purchased separately.


Q:
Is this the proper thermostat kit for a 2004 Yamaha F150 4-stroke?
A:
Yes, this thermostat kit is the match for your Yamaha engine.


Q:
I have a 1999 Yamaha S115TXRX. Is this the right themostat for my engine?
A:
Yes, this is the correct thermostat for your engine.


Q:
Will this fit a 97 8mlhw?
A:
No, the 18-3608 Thermostat Kit is designed to replace Yamaha 115hp & up. Look in the Description tag to see what engines it will work for.


Q:
Is there a picture of gasket?
A:
We can offer a photo of the part number, but we will need to know motor information.


Q:
What gasket is need for this product?
A:
The seal is included with the purchase of this thermostat.


Q:
Will this fit a 90hp outboard?
A:
This is a aftermarket part. We need your engine model number to look up a diagram of your engine to see if this part matches up to the OEM part number for your engine. Please email, chat or call in with your FULL engine information including engine manufacturer, horse power, year and model number.


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