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OldDad27
September 25th, 2012, 03:03 PM
Receiving conflicting information for Generac/Onan GT-990 V-Twin Engine - Spark Plug Gap Settings.
Champion #RC14YC says the plug is pre-set at 0.030" gap for that engine, Generac Manual says 0.040" and a Local Generac Service Technician suggested 0.025".
I live in Western NY - winters are not too severe but can get very cold at times. Summer conditions can sometimes reach 90 degrees F. or more. I already have these plugs and can change them very easily but what is the best gap setting with these variable conditions? :confused:

John R
September 25th, 2012, 04:17 PM
My manual shows 1.02mm/0.040 inch for the GT 990.

SkipD
September 25th, 2012, 04:57 PM
My manual shows 1.02mm/0.040 inch for the GT 990.And there have been a lot of recommendations here over the last few years to tighten that up to .030".

I run my plugs at .030" gap (in a 5416 generator) and the engine has run very smoothly for years with the ambient temperature ranging from about -15F to just short of 100F. I do use a battery warmer (blanket style) when the temps are below freezing.

GenMan
September 25th, 2012, 05:35 PM
if it is on propane , i gap them at 0.025" , if it is natural gas , i gap them at 0.040 , I am in Ontario and we can get pretty cold , so by closing the gap up it helps allot .

ohmslaw
September 25th, 2012, 08:28 PM
Receiving conflicting information for Generac/Onan GT-990 V-Twin Engine - Spark Plug Gap Settings.
Champion #RC14YC says the plug is pre-set at 0.030" gap for that engine, Generac Manual says 0.040" and a Local Generac Service Technician suggested 0.025".
I live in Western NY - winters are not too severe but can get very cold at times. Summer conditions can sometimes reach 90 degrees F. or more. I already have these plugs and can change them very easily but what is the best gap setting with these variable conditions? :confused:

What size Generator?

ohmslaw
September 25th, 2012, 08:57 PM
What size Generator?

The 20KW 999cc uses r12yc@.030 and the 992cc engines use a r14yc4 @.040.

OldDad27
September 25th, 2012, 09:36 PM
The Generator is a Generac, Model #5243, 15KW Natural Gas Powered Unit.
I set plugs at .030" this evening while performing annual service. (After running unit 12 minutes-some cool down time then oil change, filter, plugs, air filter, general cleaning, etc.)
The unit started right up witout any hesitation !!!:D Ran smooth and shut down with no problems!:) I guess .030" vs .040" gap makes a difference.
Thanks to all who replied.

OldDad27
September 25th, 2012, 09:45 PM
And there have been a lot of recommendations here over the last few years to tighten that up to .030".

I run my plugs at .030" gap (in a 5416 generator) and the engine has run very smoothly for years with the ambient temperature ranging from about -15F to just short of 100F. I do use a battery warmer (blanket style) when the temps are below freezing.

Does a battery warmer really help that much? I installed my generator in 2007 and haven't used one. Being this battery is going on its 5th year of a 6 year battery would a blanket warmer be advisable now? Will it extend the life span?
OldDad27

SkipD
September 26th, 2012, 03:03 AM
Does a battery warmer really help that much? I installed my generator in 2007 and haven't used one. Being this battery is going on its 5th year of a 6 year battery would a blanket warmer be advisable now? Will it extend the life span?
OldDad27I have definitely noticed improved starting when the outside temperature is down around 0F or below. I use a device that turns the blanket on below 35F and off when the temperature warms up to 45F.

murphy
September 26th, 2012, 04:44 AM
Does a battery warmer really help that much? I installed my generator in 2007 and haven't used one. Being this battery is going on its 5th year of a 6 year battery would a blanket warmer be advisable now? Will it extend the life span?
OldDad27

In my experience nothing will extend the life of a car battery. They invariably die 1 month after the warranty expires.

Have you been checking the water level in that battery to verify the plates are still covered?

In a generator that you are depending on to supply emergency power the battery should be changed every three years unless it was a cheap battery to start with in which case it will probably not last much past 1 year. A 6 year warranty battery is not going to stay at full starting capacity for 6 years. That 6 year warranty is almost certainly a pro-rated warranty where they will give you $10 off on a new battery in the 6th year. That's a marketing strategy to get repeat business. It does not mean the battery is guaranteed to last 6 years.

YMMV
;)

OldDad27
September 26th, 2012, 08:59 AM
Could you provide me with that warming blanket information and the thermostat device? Where do I purchase such an Item? Thanks for any help.:)
OldDad27

SkipD
September 26th, 2012, 10:31 AM
Could you provide me with that warming blanket information and the thermostat device? Where do I purchase such an Item? Thanks for any help.:)
OldDad27The battery heater blanket which I used (sized for a Group 26 battery) is the Kat's model 22100 (http://www.amazon.com/Kats-22100-Watt-Battery-Thermal/dp/B000I8VKZ8). I power it through a Thermocube TC-3 thermal switch (http://www.amazon.com/Farm-Innovators-TC-3-Thermo-Cube/dp/B0006U2HD2/ref=sr_1_1?ie=UTF8&m=A25DVOZOPBFMAN&s=hi&qid=1229885084&sr=1-1) which plugs into an ordinary receptacle that I installed inside the generator's battery housing.

OldDad27
September 26th, 2012, 02:02 PM
The battery heater blanket which I used (sized for a Group 26 battery) is the Kat's model 22100 (http://www.amazon.com/Kats-22100-Watt-Battery-Thermal/dp/B000I8VKZ8). I power it through a Thermocube TC-3 thermal switch (http://www.amazon.com/Farm-Innovators-TC-3-Thermo-Cube/dp/B0006U2HD2/ref=sr_1_1?ie=UTF8&m=A25DVOZOPBFMAN&s=hi&qid=1229885084&sr=1-1) which plugs into an ordinary receptacle that I installed inside the generator's battery housing.

Thanks for that info.:) I'll look into getting these items. Can't hurt to try.;)
OldDad27

techntrek
September 26th, 2012, 08:20 PM
My experience says lead acid batteries last 5 years, so I replace at 4 in a genset.