overheating 302

[calwldlif]

Re: overheating 302

2 things
1 verify your water system sucks water
(use a tank filled above water pickup)
have a water hose in tank to fill as motor
hopefully sucks it out.

take the possibilty the water hose is forcing
water up the pickup out of the mix.
possible leaky pickup system.

2 the back flush I was talking about involves
removing engine circulation pump(water pump)
remove thermostat and put water hose down
through the block to force junk out the block through
holes opened after removing water pump.

the previous posts are good advice
BLK Blu has a good procedure.

It is always good to verify it really is hot,
it will save you time and money.

Yes head gaskets can be verified.
Don't get ahead of your self, don't over think
1 test at a time.
I don't know how many times I have chased
my tail thinking it had to be something bad,
and not checking the basics

Verify the system sucks water like it should.
If not, then you know it the RWC sytem.
Raw water pump
leaking hose
bad fitting, ect

If it pulls water to the raw water pump good then
check that it goes through exchanger, block, ect

1 step at a time

 

[northvanwatertaxi]

Re: overheating 302

If my mercruiser sterndrive pump is not forcing the water out the risers until I pull the hose off the the water fows out, what is the reason for this? is the exaust keeping it out?
Also the mechanic I talked to said we should change it to raw water cooling to diagnose the problem I think that's worth trying.
Don S if your not out boating could you let me know what you think?

 

[northvanwatertaxi]

Re: overheating 302

looking for a big container....

 

[northvanwatertaxi]

Re: overheating 302

went to the dollar shop and got a meat thermometer.
the temp of the coolant showed much less than the engine temp gage said. so I was going to get a new gage but, after awhile the temp started to climb way up to 180 + after being on the muffs idling for a long time.
I turned the engine off and later, took the thermostat out and tested it on the stove, it starts to open at 140f but won't fully open until the water boils.200+
I think that the NEW thermostat is either broken or wrong , I will get a new one tomorrow, test it and install Hope that will do'er

 

[northvanwatertaxi]

Re: overheating 302 It's cool!

Re: overheating 302 It's cool!

Hope i'm done! going to take it out asap!

 

[freddyray21]

Re: overheating 302

always check the thermostat first thing

 

[Bt Doctur]

Re: overheating 302

If everything else fails, drop the lower and install muffs and check water pump base gasket for leakage,copper tube may be too short or damaged from corrosion,water pocket cover may be damaged from an overheat .install a hose on the copper tube and check for leakage.

 

[northvanwatertaxi]

Re: overheating 302

Thanks Boat doctor, that's a great tip to check waterpump, I will remember that one.
checked the gear oil too and it's clean no water apparently the water pump Base leak is a major cause of water in the oil.
after the 1st impeller self destructed I back flushed the copper hose down and up and did that to all the hoses and found the impeller bits down by the intake
I'm happy to announce the risers are so cool you can just leave your hands on them. the temps 140 but goes below a bit. but held steady for the fist time all summer!
The boat has tons of power, took it to cruising speed and watched the temp climb to 180
risers cool after slowing and temp went to 130
Not sure what to do next. I'm going to be checking the gage and water is full