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Running without a tstat

chiefalen

chiefalen

Banned
Question gentlemen:

What i

Question gentlemen:

What is your opinion on running a 140 hp 4 banger without a t-stat. Please explain your opinion pro or con.
 
"chiefalen
An engine thermost

"chiefalen
An engine thermostat, is a device that keeps the engine running at its most efficient operating temperature. Your call.
happy.gif

Bert"
 
"I wouldn't, if I was keep

"I wouldn't, if I was keeping it.

w/o the stat, it will likely run cold. Never reach designed operating temp. extra friction, wear and tear. If operated for short periods, the oil will likely sludge up real fast and we all know that will kill an engine fast. if it doesn't sludge up, the water that won't get evaporated out and the combustion byproducts will make that acid mess in the oil will accelerate the wear.

Certain raw water cooled systems make use of the pressure rise a stat provides; eliminating it could cause cooling issues in those."
 
"a cold running engine require

"a cold running engine requires more fuel (hence the choke.

Its Ok to run temporarily without it testing the rest of the cooling system to see where an over heat issue is.. but it's not worth the cost. They are cheap <$10us if you look hard, and only 2 bolts to replace."
 
"Ayuh,... Not only does the T

"Ayuh,... Not only does the T-Stat hold the water in the block for Temp control,...
It controls the water flow through the T-Stat housing,...
Aka; the exchange/ rejection of new raw water...
Without the T-Stat, it can be running in a localized overheat condition, without showing so on the gauge..."
 
What rating T-Stat do you reco

What rating T-Stat do you recommend for this purpose? It may be of benefit discussing this in relation to short and long run journey. Hours of standard use per trip!
 
"Ok i posted the question but

"Ok i posted the question but held back my opinion.

I have had such bad luck with t-stats running in salt water in i/o motors.

Allow me to go back 30 years when i first got my 1976 evinrude 70 hp on back of a trihull 16' Arrowglass open bow.

Never kissed saltwater never needed the t-stat removed. Never ever any starting problems.

Sat sometimes for years and not used, military service that boat and motor kept me sane after coming back from nam.

Flash forward i needed a new trailer and lo and behold a friend had a trailer sitting on the side of the road with a boat on it.

So i asked him how mush, he said 500 i said all i want is the trailer, he said take the boat and tittle or nothing and give me 300.

It had a 2.5 stringer, wish i knew now, back then.

2500 dollars and over that winter i tore everything out and from the deck up rebuilt everything.

Well 5 years latter to no fault of the motor, or maybe a little cause the head went, from saltwater use.

New rebuilt head, and the corner head bolt hole, got over torqued. Pulling the hole out and caused a crack down the side of the block.

Looking all over for a motor i wanted a 3.0.

Ebay a guy near me has a boat with a merc 85' 400 dollars start bid. on a trailer.

I wait a week watching, call him on the phone day before auction was to end no one bid.

I said if the motor starts in your driveway i'll take the motor.

He said lost my buss. i need money take the whole thing trailer and all.

I said ok if it starts in your driveway.

Drive over start the boat, and hand him cash, he hands me the tittle and i put air in the tires and pull it home.

So now i got my trailer for the 16 footer the merc motor in my boat.

Long one guys heres the kicker, the freekin bought at the johnson evinrude dealer t-stats kept getting stuck closed, both in the omc motor and the merc motor.

Just when i got the new to me motor i put a brand new bought at the merc stealership t-stat go out on raritan bay fist time and it sticks closed, and bursts the hose kabaam thank g-d the dog house was over the motor or my friend would have got steaming water all over him.

Remove the t-stat go back and buy another , sure enough sticks closed.

Friend says to me when you gonna keep throwing away 15 dollars and just leave it out like him.

He got the same motor, took his out 15 years ago.

So i start asking everyone else i know even at the dock if they run t-stats?

Every body here RUNS WITHOUT ONE, not one guy has a problem.

One guy 30 years."
 
"Tha answer to your "what

"Tha answer to your "what ever it is" senerio is.

A closed cooling system...... That is what they are for. SALT WATER. ok brackish water too.

In a real world situation the lack of a thermostat will not have much negitive affect.

So the motor may run a bit cooler, so what!

So if it works fine without one just "do it"!

Many a boat with circulation issues are run without thermostats until someone wants to spend the $$$$$$$ to make it right.

It is what it is...........enough said."
 
"My SWAG.... The T'Stat w

"My SWAG.... The T'Stat was in backwards and you kept putting the new one in the same way, or was the incorrect one for the motor...i.e. T'Stat housing was replaced with a different one that does not match the replacement guide.

I once bought a 25 ft Bertram at firesale prices since the owner panicked... One engine smoked black very badly when warmed up. The idiot mechanic had replaced the heater coils in both the carbs (twin 165 MERC) choke circuit, however, he installed one backwards. A 15 min Zero cost fix."
 
"Here is one for you, the guy

"Here is one for you, the guy i bought the 3.0 merc motor that was in the boat, cause the 2.5 fiasco, had the flapper / shutter blocking the exhaust.

I found it as i was pulling apart the transom and all the other goodies before i got rid of the hull.

So i surmise, that the motor kept overheating the owner just couldn't figure out why cause there was a new mani and riser on the motor useless to me, cause i need a omc mani and riser to match up to the exhaust tube.

As to me putting in the t-stat backwards or using the wrong t-stat, bought at a merc stealership, or used the wrong one in the omc motor, i can only state no they were the correct ones.

I won't even go into how many years i have been working on airplanes, jet propelled or prop driven. As a matter of fact i was in the last Air Force class that taught us prop and jet.

Maybe it's the dirty raratain bay i boat in, or small stones i don't know.

I do appreciate the comment though."
 
"I'm with Kghost, if you&#

"I'm with Kghost, if you're running in salt water you should have a closed cooling system. No matter how much you flush your motor out you won't get all salt out of it. At least with a closed cooling you're limiting your salt intake to just the exhaust manifolds/ heat exchanger/ exhaust outlet, instead of the internal engine."
 
"2 85' motors. Both run on

"2 85' motors. Both run only in saltwater.

And the merc one in my boat now.

Don't know how mush better then you can get then that.

Oh both raw water cooled. None of my buddies run closed systems.

We know all the stuff that can happen with closed, just more problems.

Not to mention all the outboards."
 
"Never had a single problem wi

"Never had a single problem with my closed cooling system and my boat is a 1984. all original never ever had to fix(the closed cooling part anyway). cars have been on a so called "closed cooling" system for 75+ years without much problems. E/G is a lot more stable than water is at operating temp also.... As far as the O/B engines, they make "salt-water" series with special internal parts to resist internal corrosion from the salt water. Your raw water cooled Merc DOES NOT have special coated or lined internal parts!! Thats exactly why they make closed cooling systems....for salt-water.. I agree with PugetSounder and Kghost on this. If the engine didnt need a thermostat then the manufacturer would of assembled it without one!!! I am glad however, that you havent had many issues because I do not wish on ANYBODY to have bad luck or problems with any vessel because WE ALL knows what it feels like to be stranded in the middle of a BIG body of water without help. kinda a lonely feeling!!Good Luck"
 
"The free flow of info. is wha

"The free flow of info. is what the net is all about,good men of good intent, can disagree.

Jes i never wish anyone, bad luck, i also wish you,a happy holiday, peace on earth and good will to everyone who reads this.

I posted this on another website 2008.

The tow of shame !

Ok I just clear the sail boats at Keyport NJ.

I'm running at about 3500 rpm 20 mph everything is perfect, oil pressure, temp, charging, all is perfect.

I'm in about 25 feet of water per my fishfinder/depthfinder.

It's a great day to be alive. I have my 13 year old son the fishing machine with me. Weather is perfect, tide is coming in, slight chop.

I get to the middle of the bay oh maybe 15 minutes, and boom, it happens.

A loud boom the boat feels like i hit a wall and it revs high like i'm in neutral.

Temp. goes to 200 and i shut her off.

I know i didn't hit anything.

I call my friend, he says i'll be there 2-3 hours.

Ok I throw out the anchor. And were fishing.

Put up the Bimini top, and wait.

I calm down, and start thinking, what happened, maybe not in those words.

After all this is a family site.

My friend gets to me and I pull the anchor and he starts to tow me in.

Longest ride in at maybe 1 mph past maybe a 100 boats.

Never been so red faced in my life. Dejected don't even comes close to how i feel at the time.

I get the boat on the trailer and home ok. I's in the driveway now.

OK thats my tale of woe it happened yesterday. Oh by the way i got a keeper and one short the fishing machine nothing.

Now to the question! I need the minds of omc owners and mechanics.

Never easy for me to ask for help!

Ok motor off throttle in gear, Drive fully down. I turn the prop and the ball gears move both of them.

I'm thinking what the ---. No way got to be the water pump shaft stripped out got to be.

I'm turning and turning the prop the ball gears both of them turning.

Has anyone ever heard or seen the ball gear strip on the shaft coming out of the intermediate housing. I don't think the shaft is turning just the gear.

I have not gone out to the boat this morning yet except to walk the hot dog, dog we have. I walked past it but have not touched it yet this morning.

And in the same thread about a week latter i posted:

Ok a update and a tip for all stringer owners.

Was the coupler, very, very unusual for it to go. But got a used one and worked great.

Started it in the driveway no problem. Shifted good, Tattle-tale stream strong on the ball gears.

Go out to the bay cause i'm itching to see if i got any mechanical skills left.

Have on the boat me my 16 year old son who is the deer slayer but he don't like the bay to mush. His boy scout friend and farther, 4 people in all.

A perfectly gorgeous day 6:30 in the morning, Bay flat.

Boat is running perfect.

Get to spot one drop the lines, no fish, start her up, get to spot 2 about 1 mile away, drop the lines, no fish.

Start her up go 100 yards, and she strips out the water pump shaft. Shut her off 2 seconds.

Did I as a reasonable person bother to check the water pump shafts, when i was waiting for the coupler in the mail? No. I have to find out on the water.

Throw out the anchor.

Same guy in his bayliner comes for me in 8 hours cause he's working.

Heres the warning guys. If you have a stringer.

CHECK YOUR WATER PUMP SHAFTS EVERY YEAR.

Mine were good 3 years ago. I know i checked them.

Out drive apart waiting for the shaft i ordered. One goes they both go.

One i had.

This all happened AFTER i replaced the 2.5 omc with the 3.0 merc motor. Was a real interesting year."
 
"Chiefalen,

Why would you p

"Chiefalen,

Why would you post a story like this???

What does it have to do with anything technical?

Not to be mean here but WHO CARES about an OMC anything!!!

OTHER MOTOR COMPANY....

Anyone running a stringer OMC is destin for failure...........Of all the marine products I have worked on that has to be the worst design I have ever had the MISFORTUNE to work on..............

Also why post it on the merc page???

I cant speak for anyone else but I certainly dont care to hear or read much about OMC or there short commings on here"
 
"Tough room, but it did have t

"Tough room, but it did have the coupler thingie, and shaft thingie, a omc and merc drives both have shafts.

The omc stringer drives were and are great. Turn further, no, exhaust bellows, no u-joint bellows don't have to remove the drive to pull the motor.Don't have to align the drive and the motor, when i do pull the drive.

I can lift it higher then a merc. I can pull the motor and leave the bell housing in place.

I had the option of using the alpha one that came with the boat the 3.0 came with, and still have on the side of my house.

Matter of fact parts are easy to come by.

I thought i would reply to the post about being towed.

Still wish you a good holiday, Kghost.

Just wondering whats kinda name is Kghost?"
 
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