Too Much Oil In Snowblower

Oil is super important to your snowblower, nothing will kill an engine faster than a lack of oil but can too much oil be bad, you bet it can.


But don’t panic, too much oil isn’t as bad as too little and it’s an easy fix. I've been a mechanic for over twenty five years and I'll show you the fast fix.

Too much oil in a snowblower engine will cause it to blow white smoke. Other possible symptoms of too much engine oil, include:

  • Engine won’t crank
  • Oil leaks
  • Spark plug fouling

In this post you’ll learn why too much engine oil in your snowblower can be harmful. You’ll also learn how to correctly check oil level and what to do if your engine oil is overfull.

Mower gas cap

Vented Gas Cap

Too Much Oil In A Snowblower Is Bad

It’s true that too much oil is better than too little, but it’s still possible to damage an engine with excessive lubricant.

Some of the common symptoms include:

  • White smoke – Too much oil can cause oil to migrate to the carburetor through the crankcase breather. The oil then enters the combustion chamber and causes plooms of white smoke.
  • Engine won’t crank over – too much oil inside the engine prevents the crankshaft from moving. This often convinces operators they have a flat battery (key start) or pull cord issue.
  • Oil leaks – Excessive oil causes excessive crankcase pressure – this often results in oil leaking from cranks seals and pan gaskets.
  • Spark plug fouling – oil that enters the combustion chamber will foul the spark plug and cause misfiring.

Your snowblower engine is equipped with a driven oil lubrication system (identified by the presence of an oil filter) or splash lubrication (no oil filter).Too much oil is especially bad for a splash lube system.

This system uses paddles attached to the crankshaft which smack the surface of the oil causing oil to splash in all directions.

However when the oil level is above the paddles, splashing isn’t possible and the engine isn’t protected.

Mower gas tank

Winged & Threaded caps

Check Snowblower Oil Level

Running low on oil is a common cause of engine failure. Excessive heat caused by the lack of lubrication causes the internal metal components to get so hot they fuse together, when this happens to an engine it seizes and that’s a condition that can’t be repaired.

I tell my customers, it’s best to check engine oil every time they fill up the gas tank. Modern engines don’t use much oil but they will use a little. Oil is a lot cheaper than a new engine.

Some of the more expensive snowblowers may be fitted with a low oil switch. The switch will prevent the engine starting in the event of low oil.

Checking oil is a simple procedure, follow these simple steps:

  • Park snowblower on level ground and allow engine to cool
  • Locate the dipstick, marked with an oil symbol or the word “OIL”, the dipstick cap may be a contrasting color
  • Remove and clean dipstick
  • Reseat the dipstick (do not screw home threaded type dipsticks to test)
  • Remove the dipstick and read level

The upper dipstick mark signifies full and a lower mark to signifies low oil, the area in between may be hatched, this indicates an acceptable oil level.

If you need to top up the oil, add only a little at a time before reading the dipstick.

From empty, the average snowblower engine only takes about a quart of oil, and as you know, it’s easy to over do it.

Most engines will happily accept 5W30 or 10W30, mixing oil types isn’t advised generally but for tops it’s fine.

That’s it, good Job, you’re a pro!

Vented mower gas caps

Vented gas caps

Remove Excessive Snowblower Oil

Too much oil will need to be removed. In the workshop I use a specialized tool called a gas and oil syphon. It’s not an expensive tool and if you do your own maintenance, you’ll love it. You can check it out here on the “Snowblower maintenance tools page”.

The syphon may be used to remove just the excess oil from the engine. Otherwise, you’ll need to remove the oil drain bung and that can be messy trying to gauge when enough oil has been removed. Instead, and if you don’t have a syphon, go ahead and change the oil out completely.

Snowblower oil should be changed once a year, and preferably before the new season begins.

Catching the old oil and reusing isn’t advised, grit from around the exterior of the engine may fall into the oil catch and contaminate it.


Auto Technician and Writer at Lawnmowerfixed | Website

John Cunningham is an Automotive Technician and writer on I've been a mechanic for over twenty years, I use my knowledge and experience to write "How to" articles that help fellow gear-heads with all aspects of mechanical repairs, from lawn mowers to classic cars.