V4 1992 thermostat question

[pn]

i just recieved two new bullet thermostats off line and checked them in hot water with ir gun. part no. 434137

this is what i found. The one stamped O2BX opens at 145
The one stamped H1C opens at 155

I'm not too worried but should i be?

 

[emdsapmgr]

Re: V4 1992 thermostat question

Think they are supposed to open at 143. Your original factory parts list says that crossflow takes a 393659. It supercedes a few times to: -0437414->0434841->5005440. The thermostat you purchased is for a 3-cylinder/4 cyl looper.

 

[pn]

Re: V4 1992 thermostat question

thanks for the response, i have a 1992 v4 120tlend looper, part no. 434137 appears to be the right part according to the evinrude parts lookup.

plastic bullet type veratherm.

not sure if i should really worry about the discrepancy of opening temperature by 10 degrees

 

[emdsapmgr]

Re: V4 1992 thermostat question

Thanks for correcting me with the correct model. Sometimes it's difficult to give the exact correct information without the model number in the original posting. Have you installed them on the engine and checked the actual head temps with the laser gun? While not a huge temp variance, the scenario that would concern me is when the engine is idling in gear in the dead heat of summer. A 145 stat can permit engine head temps to normally creep up to 155+. If yours already is at 155, cyl head temps might it creep up to 165+ in the summer. To me, that's getting in the "too warm" range. Maybe a looper expert can comment.

 

[pn]

Re: V4 1992 thermostat question

my apologies for not detailing yr model info, So i've installed the new thermostats with new rubber seats and one new spring and this is what've found. To take out the seat holders for me is impossible so i just pulled out the seats with needle noses and shoved the new ones in with some grease. Made sure they were fully seated by feeling them. also the original ones were siliconed in place, mine are greased in. Pretty sure they wont fly out though. Running on muffs full blast, port 90-100, starboard 110-120.
I put the hot thermostat on the port side too.
Obviously too low, but why. On my motor the poor alignment from the heads to the block etc. doesn't allow the thermostats to seat correctly on the rubber seat thereby letting water through regadless of when your thermostats open. Again, thermostats sit off kilter, Oh, well better to run too cold than too hot. Was going to test the old thermostats in the water but i'd be a waste of time.

 

[pn]

Re: V4 1992 thermostat question

Here is a couple of pictures of the old dissassembled thermostat, you can put a very small rod through the bullet tip and simply unscrew. If I figured out how to open them up earlier i wouldn't have bought new ones as they are easy to check and clean. Putting a heat gun on them pushes out a little pin on the bottom whereby opening up the flow. To dial in your motor one can adjust the temperature by messin with the spring lengths inside the thermostat and the one outside which holds the bullet to the seat. Also there is a picture of my old off kilter seats. Hope this helps someone.