outboard stat

I have a 2 stroke outboard and the thermostat is jammed in the open position
I know running without a stat keeps the motor too cool to burn off the two stroke oil.
If I run it with the stat jammed in the open position,will the motor get
warm enough eventually to burn the 2 stroke oil with the fuel.

"V"

 

The motor will take longer to warm up properly, increasing engine wear, more likely to conk out when setting off, but you can live with it. I suppose in very cold waters it may not warm up sufficiently at all, which is not much good, why not just replace the thermostat(s) ?

 

Hello Mr E,
I might need to use the boat shortly.
I have located a new stat,so I will be replacing it.
The water is a bit on the cool side here in the UK,so it's probably the best bet like you say.
Thanks for your reply
"V"

 

G'day V, I was thinking it might be more of a problem with your cooler waters. Might as well replace it, not a huge job.

 

20 minutes I reckon Mr E.
I don't know what the prices are like in OZ,but they want £35 at least here.
It pees me off a bit,when you can buy a stat for a car for £7 or £8.
It seems like as soon as you add Leisure or sport to title,they jump in with both feet on the price.
Well,that's my little moan for the day,Haha

 

Just did one on a Honda 90 and it was 10 minutes, 6 of this was cleaning the old gasket off.

 

Hi PAR,long time no see.

The stats are a pretty straightforward job I'm glad to say.

I've just got a 14ft family speedboat with a nice deep freeboard and plenty of SS safety rails,it's got a nice shaped hull and never had a repair to the hull itself.
There's plenty of room behind the front seats to do a bit of fishing.
It had no controls on it apart from the steering.
I'm in the middle of fitting a twin lever control box and cables to suit
an Evinrude motor.
Should have it on the water inside the next couple of weeks.

 

Youi can test the things in hot water if you want to check that it actually is kaput. But not worth putting back in.

 

Hello again Mr E,
I have tried it in hot water,it just stays open even when I have let it cool.
I think jamming open is a failsafe by the manufacturers,probably to stop
the engine overheating.
Like you say it's Kaput
We're getting a glimmer of summer here,so I'll have to shape myself.
I have just treated myself to a nice leverdrag reel,can't wait to try it

"V"

 

Many thermostats are designed to fail in the open position, just as you suspected and you're right, it's a safety feature. Also, depending on the engine, many are designed to recognize specific temperature ranges and limit RPM if outside the acceptable ranges. This electronic feature commonly restricts RPM to 4,000 or less, so you can limp home without cooking stuff.

 

number 1 reason for poor idle is being too cold

 

No2 being aromatic gum somewhere in the carb(s)?....

 

Most thermostats in raw water cooled engines fail because something gets stuck in the gap. A tiny shell, shrimp, shard of plastic or wood splinter prevents the valve to close completely and distorts the mechanism.
I've never had an automotive thermostat fail in the last 50 years, in outboards and stern drives they last just a few years.

 

Corrosion is another issue. The Honda 90 I just did was badly corroded and I see this a lot. I can't be exact about what caused it to fail, but there were enough indications it was bad visually, to not bother testing it (I did anyway).

 

only if they have ethanol in the fuel and I dont think the UK is that silly