Engine Cooling

[John Doerfler]

What are the risers?
John Kyle Doerfler

[Mike Harry]

Risers sit on top of the exhaust manifolds (the elbows ) or on the back of the log style. Ive seen your pictures, I cant remember which ones you have.

Just looked again at the pics. You have the same style exhaust I have. I wont say your elbows are not clogged, but I wouldnt think they would be. I would think that is mostly a problem with cast iron exhaust.

[Mike Harry]

Stupid question...... but Ill ask anyway. Have you only tried one 160 T-stat? Is the temp stamped on the T-stat?

As cheap as they are I would make sure you actually have a 160. You might even want to try a 140 for now. Ive got a buddy who works in an auto parts store..... well lets say everything isnt always as it seems and everything doesnt always get put in its right box.... ect. ect.

[John Doerfler]

Yeah, I have tryed several Temp ranges and tested the ones I have bought in boiling water.  You know its almost like the water that is passing over the top of the Tstat exiting to the manifolds is so cool that it cools the Tstat because of heat transfer through the metal.  I had a mechanic friend tell me to try drilling a few holes in the Tstat.  I might try that.  The boat began having the issue about 11 years ago, long before I restored the engine and I just never ran a Tstat in it all these years.  But now that Im trying to restore the boat I want everything perfect.  Even though I have tryed 2 new circulation pumps I still think something is a little fishy there.  Could the circulation pump be pumping water the wrong direction? 
  Gongchuan, could you do me a favor and see if your large hose that goes from the Tstat housing to the circulation pump swells a little with pressure when you rev the engine?  Its the hose that says Hardine Marine on it.
John Kyle Doerfler

[Mike Harry]

ill take a look at it. My boat is in restore mode too. I only run it on the trailer right now, she is not lake worthy right now. Ill see what I can come up with though.

[John Doerfler]

I think I am going to try drilling 4, 1/8" holes in the Tstat.  A local mechanic told me to give that a shot.  You know its hard to imagine that Tstat wanting to open when there is cold water flowing over the top of it.  This morning I tryed taking the 3 bolt cover of and running the engine to see if the circulation pump is flowing in the right direction and it appears that it is, so I will rule that one out.  Boy, I started the engine and that baby really spewed water out.
John Kyle Doerfler

[Mike Harry]

Does your water neck (next to the Tstat) not have a bypass hole in it? Mine does. Its not the exact same style as yours, but should work the same.

[John Doerfler]

Yeah it does,  I have some great pictures of it I will put in my personal profile.  Thanks for the advice.  I really appreciate it.
John Kyle Doerfler

[John Doerfler]

Drilled some 4, 1/8" holes in the Tstat and it seemed to work good in the driveway.  Going to try it out tommorrow at the lake.  Keeping my fingers crossed.
John Kyle Doerfler

[Joel]

I'm having in the SAME EXACT problem...  Changed the thermostat, etc, etc...  Cant figure it out except it doesnt appear to move enough water - Yeah, I know...  DUH!  Maybe the impeller is too small... the hoses are too tight...  who knows???

My question is DOES IT REALLY NEED A THERMOSTAT?  Will it still perform after warming up???  The lake water isnt exactly freezing...  more like 83 F...

Ron?  Dan?  Phil?  Anybody?

[chrisheile]

Escuse me if I missed something earlier but you don't by chance have the petcock at the transmission cooler open do you?

[daveo]

I have a full flow therm. in my boat (just a thermostat without any guts) my auto mech. suggested it and I've never had a problem with performance but... any mech. will tell you that an  engine is designed to run within a certain temp. range. I happen to be in Tn. and our water is pretty warm in the summer (around 90) so my temp is usually around 140- 150   It runs a little lower in the spring and fall but i still don't see any difference in performance.

[Joel]

Chris,

I dont think so...  I'll check, but i think i would've noticed it.  Thanks!

[Joel]

Its wierd...  My Advance likes to run warmer when I'm planed & running at speed.  Goes up to about 180 F...  Then when I bring it down to idle, it cools right back down to 160...  I dont get it???

[John Doerfler]

Joel and Chris,
     I dont think my trans cooler on my 83 has a petcock.  Ive had it of many times and it looks to be a straight shot through for the water.  Maybe Chris could elaborate more on that for me.  You know guys I have rebuilt every thing on this engine with a fine tooth comb and for the life of me I cant figure out why it doesnt cool with a Tstat.  Yesterday I went to the lake armed with a Tstat with holes drilled into it and you know it worked.  It is a 160stat with four 1/8" holes drilled into it and it held yesterday at 180degrees all day long.  Weird stuff.
John Kyle Doerfler