Engine Cold Seize

[Recceboy]

Thanks for the info, Makes a lot of sense.

 

Again taught at College but not the full reasons, well not that i can remember the reasons anyway. I remember the procedure though.

[dillsue]

I was thinking of putting this under the tips thread but it may get missed and is quite an important tip.

 

I've heard may stories of peoples saws seizing for no apparent reason.

 

I have been into power tool repairs for over 14 years and we came across engines seizing quite a bit.

 

There is a thing called cold seize. Many of you may have heard about it but there are a lot of people who haven't.

 

This happens on air cooled engines and basically, what happens is:

 

If you rev the bollocks off a two stroke engine from cold the piston heats up quickly, but the outer cylinder doesn't because of the cooling air being blown around it. So the piston expands quickly and the cylinder doesn't, resulting in the piston picking up and seizing on the cylinder.

 

What you should always do is start your saws, never rev them from cold, and just place them on some soft ground ticking over for a minute or two before bringing them up to full revs.

 

The longer you leave it the better to warm the engine thru.

 

It makes me cringe, when a groundie starts a saw up and revs the bollocks off it from clap cold

 

The same principle of warming an engine up applies to all engines. They are all designed to run with set clearances between bearings/pistons etc and these clearances are only achieved when the engine is up to running temp. If an engine is worked hard when not at the running temp it will wear prematurely and in the worst case seize up.

 

There is nothing worse for killing an engine than revving a cold van or car or thrashing it up the road straight after starting and the same applies to chippers/saws/blowers/strimmers/mowers etc.

[gensetsteve]

Also dont shut the saw off after full load running. try to fill before it runs out of fuel. If you dont idle the saw down it stops at max temp with no way of cooling this can also shorten the life of you ignition packs etc.

[Alinicoll]

Great thread. I didn`t know about warming engines up. I`ve been told about chippers but i didn`t know why.

[Arborist]

I now always go gentle with engines when cold but in the truck manual is states that it is not nesicary to let idle to warm up but to start and drive off?

[wills-mill]

I now always go gentle with engines when cold but in the truck manual is states that it is not nesicary to let idle to warm up but to start and drive off?

 

Don't forget that the manufacturer would like to sell you a new vehicle in a couple of years They would say that....

 

I think the best diesel advice I've seen is my Operators Manual for the Ford 6610 tractor. It says something like- "Start the engine and hold at a fast idle (1000 revs) for 30 seconds before lifting implements or moving off, then do not use full throttle for the first 5 mins of work. After work allow to idle for 30 seconds before switching off."

 

I think that covers the majority of engines quite sweetly....

[TimberCutterDartmoor]

A lot of this is all there in the instruction manuals - people don't seem to read them anymore. When I buy a new car, machine, saw, mower, anything, I read the manual cover to cover before I touch the new item. But I'm daft like that. Yep, latent heat build up in the saw - allow to idle before switch off to disperse. How about a National Practical Front? Anyone want to join?!

[White Noise]

When I buy a new car, machine, saw, mower, anything, I read the manual cover to cover before I touch the new item. But I'm daft like that.

 

Yeah while smoking your cigar and drinking brandy ]

[geoff]

Good call Dean,That will save a few expensive mishaps for the start & thrash merchants!

[nepia]

I think the best diesel advice I've seen is my Operators Manual for the Ford 6610 tractor. It says something like- "Start the engine and hold at a fast idle (1000 revs) for 30 seconds before lifting implements or moving off, then do not use full throttle for the first 5 mins of work. After work allow to idle for 30 seconds before switching off."

 

I think that covers the majority of engines quite sweetly....

 

 

When I was 18 I was tractor driving on an estate and switched engine off out of politeness to let THE BOSS talk to me. I was disc harrowing at the time and he nearly took off. Let's just say that as the result of his 'words of advice' I've always warmed engines since and tried to let them idle after work! Thanks Gordon.