TOPIC: My 67' 80 hp is running HOT?

I will start by telling you what i have done so far.
cleaned & kit the carb. new points & condenser
kit the fuel pump. new varitherm. new impeller & o rings on the pickup
New spark plugs and clean the reeds. new rectifier

so now i have a motor that runs awesome! But it runs
alittle hot! I can touch the heads and there semi hot, the
flywheel is pretty warm too which is warming the rectifier
its pumping water pretty well however my low speed is at about 2 & 1/2 turns
compression is about 85psi on all four cylinders warning lamp works but
doesn't come on
My question is do these motors run hotter?
Maybe head gasket? the plugs look good as far as color go's (light carmel)

I dont know what to try next, any help would be greatly appreciated!

Thanx,
Matty83

The ebay item id given is invalid, no result has been sentHi, Matty, how warm is the flat exhaust manifold cover at the back of the block?

It should be fairly cool or perhaps lukewarm, but the heads and block will be considerably warmer (around 125 deg F) due to the thermostat and the way water flows thru the powerhead.

If you can't hold your hand on the block or heads, it's running too hot.

If the exhaust cover is hot as well, there's something wrong. But if you're getting good water flow out the exhaust relief, you should be OK.

Infrared thermometers are readily available and quite inexpensive these days, a handy tool to have when you're troubleshooting overheating issues.



HTH.........ed

Hi ed,
Tha!nks for the advice! I do believe that the ewxhaust plate was pretty warm!
I'm going to check in the morning, is it possible that there's something in the water jackets
clogging them up? She's running really good I've been out in the river a bunch of times, shut
her down and she always started right back up! So i hope it's I've over looked or really
simple, a engine rebuild can really put a damper on my summer!

matty83

Flywheels do run warm as they are part of the charging system.

---

These motors do throw out a lot of " water vapour " after coming down from a high speed run.--This is often interpreted as steam and overheating.

Hello professor.
yes my motor does throw water vapor. i glad to hear its normal. i took her out this morning, she
Was alitte warm. I'm going yo get a lazer thermometer and mess around tobe on the safe side

thanks ed & professor for your help! I will post an update, especially if i come across something
significant. After all knowledge is power!

Sincerely matty83

Not sure totally about your particular motor, but I acquired a little 5hp royal atlas a while back that I thought was getting hot too...couldn't hold a bare hand any where on the motor.

Guy told me to splash water on it, if it sizzles, it's overheating.

I totally thought I'd be cooking noodles with the water I'd splash on it.....once I did though, no sizzle at all, anywhere....

Put a infrared thermometer on it and it was barely 110 degrees all over......felt darn hot with a bare hand I gotta say..

Hi garzilla,
I'm on the river right now and just did that test and "no sizzle"!
She's been running really good! I think she's going to be ok!


Thanxx!
Matty83

The videos a little shaky i was filming and driving!

matty83 wrote:

Hi garzilla,
I'm on the river right now and just did that test and "no sizzle"!
She's been running really good! I think she's going to be ok!


Thanxx!
Matty83

Lucky! Wish I was on the boat..

For some reason it didn't upload video, my phone hates me!!

Matty, what fuel mixture are you running? The older motors were 24:1 rather than 50:1. I know my 1941 runs very hot if I don't mix it 8:1. I did lean it out a little from the 5:1 as called for in the instructions!

A '67 V-4 uses 50:1 fuel mix. From the description of temperature, sounds like it's doing fine.......ed

Any Johnson after 1964 should be 50:1. i run 3oz oil pet gallon. it's about 48:1

Take a candy thermometer and after getting the motor up to Max operating temp place thermometer in idle exhaust port where there should be water spray exiting. It should read around 130 to 150 degrees farenheight. Max temp is 170, These are thermostatically controlled motors.