200 merc black max

[dmottjr]

what should temp be at idle i just bought 79 v king idle temp seems high can anyone help thank you

[transomstand]

Cyl head temp around 150

[dmottjr]

thank you i think my gage is off used infared and its reading 154 in that range i should be ok love the forum im new to streams haveing a blast .....peaple love these boats and so do i

[redneckcustoms13]

+1 i dig mine as well as seeing others in theirs

[dmottjr]

ok took boat out today ran good buzzer sounded for hot motor only at 6000 rpm and goin good have low water pic up and temp gage on dash is at 160 to 170 could it be a bad poppet valve motor didnt have t stats when i bought boat i put them in plenty of water comeing out of piss hole please help me im new to outboards im an automotive technician by trade any help would be appreciated

[transomstand]

Sounds like you have an early 200, with a 190 degree overheat sensor.

Some idiot must have been "fixing" the cooling system by gutting it.

Can you post some pics of the motor with the cowl off?

Add a water pressure gauge ASAP, it makes diagnostics ten times easier.

[varmint1]

I had a similer problem on my Mariner 150, the heat buzzer would go off at high speed I would come off the throttle and let it cool down. Then one day I running it and it slowed down for me, my motor locked up. When I tore it down to rebuild come to find out the head gaskets were all eaten up and lost sealing letting compression into the water jacket. that could be whats going on with yours.

[dmottjr]

ok id on motor is 66225952 put a water pressure gage on at idle 2 to 3 psi at idle 2000 rpm its at 13 to 15 psi head temp in a garbage can running 150 to 158 water pressure seems steady could it be the low water pic up let me no what u think and thanks for the help this boat was hacked together tryin to bring it back to life lol

[transomstand]

Are you reading pressure from the 1/2" pipe thread hole at the top of the block behind the flywheel?

I really need a pic of the starboard cyl head and the exhaust plate

[dmottjr]

yes thats were im reading it from