So after the break in we took the HJ-60 from Michigan to California. Runs like a top. But as soon as we got here the thermostat went (I ordered one but it ended up being wrong), so I pulled it out on the road. The engine will warm up to the touch but runs so much cooler it only registers that it starts to get warm going up hills. It gets warm enough not to smoke at all however. (A bottle of Lucas Injector lube/cleaners and a couple times flooring it took care of the smoke issue) Is running at this cooler temperature going to hurt anything in the next couple days while the thermostat on its way? The outside temperature is between 30-50 degrees F. Also the machine shop adjusted the valves but should they be adjusted again now that the engine has got 2500 miles on it? Does it matter if they are adjusted warm or cold? The book has the specs for both.
2H - Running Cool - Any Chance of Damage?!?!
- Thread starter phatwheels
- Start date
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In the long term an engine that runs too cool will wear quickly.
Even if the outside is cool,the inside of the combustion chambers will be at normal temps.They have to be to get proper ignition.
This means the pistons and rings are expanded but the cylinder block is not which means you have too little clearance between them.
So when it does get back to proper temperatues and the engine fully expands you will get too much clearance between the cyl wall and piston rings.
Basically the engine is designed to be most efficient at about 90 C and the thermostat is there to keep the coolant in the engine jacket so it gets to those temps quicker.
It will be ok for a few days
curious,
the rings exand slightly with the heat but the cylinders themselves expand (tighten the clearencs) when warm. since this is the case then the cylinders will be too loose,not too tight if the engine is run cooler that 88C...
no?
you will be fine for the drive home but get a thermostate installed as quick as possible...
the rings exand slightly with the heat but the cylinders themselves expand (tighten the clearencs) when warm. since this is the case then the cylinders will be too loose,not too tight if the engine is run cooler that 88C...
no?
you will be fine for the drive home but get a thermostate installed as quick as possible...
Placed a piece of cardboard or "winter front" inside the grill, this will inhibit air flow and allow the engine operating temp to increase. Just remember to cut a little hole in the centre (keep and eye on operating temps and find the hole size that works best)
The way I understand it ,reading from a site dedicated to radiator tech, is that the engine is designed to expand outwards so the clearances are correct.
It expands from the inside to the outside.
If the inside is warm (pistons rings ect) and the outside is too cool (engine block) then the rings will drag on the walls slightly.
This is one of the reasons why,according to this site, an engine lacks power when cold because there is some friction in the cyls and why an engine that is started cold and switched off before warm wears out quickly.
Wheras taxi cab engines that never cool last 3x times longer than a family car engine.
Of course it is just not the cyls, but crank and bigend bearing clearances as well.
Proof of this is where oil pressure is slightly higher when the engine is cool and tolerances are tight.
When an engine is overheating tolerances become too big and the engine goes sloppy losing compresion and oil pressure.
I guess you would have to do a hot and cold compression test to prove /disprove it.
a hot engine will always have higher compression readings.
the reason an engine doesn't have the same pwer when cold is because the tolerances are not tight enough.
think of it this way, when idleing an diesel excessivly will lead to washing the walls with diesel and contaminating the oil (granted a tiny amount) themore you idle the more glaze you get on the cylinder walls, if the tolerances where the opposite then the damge would be scoring of the walls (which only happens when low oil pressure or dirt contamination of overheating of the block...)
at least this is my understanding...
the reason an engine doesn't have the same pwer when cold is because the tolerances are not tight enough.
think of it this way, when idleing an diesel excessivly will lead to washing the walls with diesel and contaminating the oil (granted a tiny amount) themore you idle the more glaze you get on the cylinder walls, if the tolerances where the opposite then the damge would be scoring of the walls (which only happens when low oil pressure or dirt contamination of overheating of the block...)
at least this is my understanding...