How long should I let my motor warm up for?

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lugoismad
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How long should I let my motor warm up for?

Post by lugoismad »

I've noticed since the weather has turned a bit cooler and the lake has dropped from 85* water temp to 70*, if I don't let my motor warm up for 15-20 seconds before I accelerate after I've been sitting for a while, that it'll bog or even die.

Once it warms up, its fine.

How long should I be letting it warm up for, before I accelerate?

Its a 84 (I think) 25hp Johnson 2 stroke 2 cylinder.
1984 Sea Nymph 14R (1457) - SOLD
1978 Starcraft Super Sport 16'

ggoldy
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How long should I let my motor warm up for?

Post by ggoldy »

Based on your own info, 15-20 seconds.....that's a 'no-brainer'. But a little carb tuning and plug cleaning/gapping may help.
Gary
Mary Esther, Florida
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CMOS
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How long should I let my motor warm up for?

Post by CMOS »

You may also benefit from installing hotter range plugs for the cold season. Try it. Just go to an Auto parts store with your standard plug and tell them you want the next hotter range.

CMOS
1982 Johnson 15 HP - in pieces, in progress
Currently boatless :(

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Pappy
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How long should I let my motor warm up for?

Post by Pappy »

Nix the hotter plug idea. Has nothing to do with how quickly an engine warms up. It can and will have an effect on how long an engine (piston) lives however.

whitetailhntr
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How long should I let my motor warm up for?

Post by whitetailhntr »

Pappy wrote:Nix the hotter plug idea. Has nothing to do with how quickly an engine warms up. It can and will have an effect on how long an engine (piston) lives however.


I understand why you would say that a hotter plug isn't the way to go and i completely agree. Though you are incorrect about the time it would take to warm up. Running a hotter plug puts out more energy(heat) which would increase internal motor temps/time to heat up. Still running a hotter plug is a bad idea. Id consider running higher octane gas or use an additive like amsoil octane boost. If in your area better gasoline isn't available.

Mark_Fisher
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How long should I let my motor warm up for?

Post by Mark_Fisher »

Running a hotter plug puts out more energy(heat) which would increase internal motor temps/time to heat up.
Wellll.... Hotter plugs have longer insulating path to their heat sink, the threads. Therefore, the plug tips run at a higher temperature.
Image

whitetailhntr
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How long should I let my motor warm up for?

Post by whitetailhntr »

Mark_Fisher wrote:
Running a hotter plug puts out more energy(heat) which would increase internal motor temps/time to heat up.
Wellll.... Hotter plugs have longer insulating path to their heat sink, the threads. Therefore, the plug tips run at a higher temperature.
Image


Exactly

lugoismad
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How long should I let my motor warm up for?

Post by lugoismad »

Pappy wrote:Nix the hotter plug idea. Has nothing to do with how quickly an engine warms up. It can and will have an effect on how long an engine (piston) lives however.
Pappy, you haven't steered my wrong yet, so I'm going to take your word on this.
1984 Sea Nymph 14R (1457) - SOLD
1978 Starcraft Super Sport 16'

whitetailhntr
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How long should I let my motor warm up for?

Post by whitetailhntr »

lugoismad wrote:
Pappy wrote:Nix the hotter plug idea. Has nothing to do with how quickly an engine warms up. It can and will have an effect on how long an engine (piston) lives however.
Pappy, you haven't steered my wrong yet, so I'm going to take your word on this.
Whats his word on this? It doesn't answer your question lol

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Pappy
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How long should I let my motor warm up for?

Post by Pappy »

Mark Fisher got it right.
The plug tip is what runs hotter.
All else is the same. Cooling system has not changed. Air/fuel ratio has not changed. The hotter spark plug is simply not transferring that combustion chamber heat into the cylinder head/cooling jacket as quickly or efficiently as the correct plug will so the tip runs hotter than the original or a cooler plug.
Following that a little farther you would think that a colder plug might warm an engine a little quicker since it transfers more heat into the cylinder head/cooling jacket faster.

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Kismet
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How long should I let my motor warm up for?

Post by Kismet »

I love this place. =D>
Kis
Enjoy every sandwich

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JL8Jeff
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How long should I let my motor warm up for?

Post by JL8Jeff »

Depending on where you're located, it could be the winter gas as well. I read about a week or 2 ago that the winter formula is already being distributed in our area. I usually run my engine for at least a minute before I pull away from the dock. EFI motors probably aren't as finicky but carb motors seem to want some heat. Nothing is worse than pulling away from the dock, stalling out and not being able to restart as you get swept downstream with the river current.
2001 Lowe Roughneck 1652 VT with Merc 60/45 jet 2 stroke

tomme boy
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How long should I let my motor warm up for?

Post by tomme boy »

Higher octane is NOT the way to go. It has more anti knock agents in it to prevent knock. This makes the gas harder to burn. You want 87 oct NON-ETHANOL. This is the fastest normal burning fuel available.

lugoismad
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How long should I let my motor warm up for?

Post by lugoismad »

tomme boy wrote:Higher octane is NOT the way to go. It has more anti knock agents in it to prevent knock. This makes the gas harder to burn. You want 87 oct NON-ETHANOL. This is the fastest normal burning fuel available.
Unfortunately, there is no non-ethanol places around me unless I want 110 octane av-gas.
1984 Sea Nymph 14R (1457) - SOLD
1978 Starcraft Super Sport 16'

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Charger25
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How long should I let my motor warm up for?

Post by Charger25 »

If your going to run the motor in cooler water/ weather as during the late fall / winter / early spring IMHO you really need a good working T-Stat to keep the motor in its proper temp range. Don't think hotter plugs in the answer
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