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Lawn Mower Maintenance

Will HEET Hurt My Engine?

By Jeff Mercer · Updated September 6, 2022 · 4 min read
Will HEET Hurt My Engine?
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What do you know about HEET? Sometimes, my people don’t understand what I mean by HEET. If you own a car, you can easily talk about this substance.

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HEET is a liquid chemical substance that is made to remove every drop of water from your gas tank.

It is not good to have water in your gas tank, so you must always have HEET in your vehicle at all times, because you may need it at any time. I know you will be thinking of its effect on your vehicle if you should put an excess of it into your gas tank.

Will HEET hurt my engine? You are not alone if you are worried about hurting your engine with this substance. Here is what to know about HEET:

If I put too much HEET in a gas tank, what happens? When you have excess HEET in your gas tank, it will not damage your vehicle engine. However, it may result in unpleasant changes in engine performance.

The effect will be more significant if the quantity of HEET in the tank is more than the quantity of gas. If this is the case, all you need to do is to add more gas to the tank to dilute it.

The primary function of HEET in your car is to get the gas tank rid of water, therefore, do not worry about it bringing problems to your vehicle’s engine. You have to read and follow the instructions on how to use it, for you to get its maximum benefits.

I am going to teach you the likely effects of having excess HEET in your gas tank in this article. Additional, I will educate you on all the things you are supposed to know concerning HEET, and what you should do in case you mistakenly have an excess of it in your gas tank.

Let us go into details without further delay.

Can You Put Too Much HEET in Your Gas Tank?

HEET is sold in bottles so you do not need too many. Given that, putting an excess of it in your gas tank is not possible.  Let us look at it this way, you can mix 20 gallons of gas with one bottle of HEET, this is about 75.7 liters. Excess use of it is when you put one bottle into a tank that has little gas in it.

Although you can safely use Heel in your gas tank, it may still in some ways have a silent effect on your car engine performance.

If for any reason this happens, add more gas to the tank to dilute the HEET. However, if the problem is not solved, pour out every gas in the tank and fill it again with new gas.

Although it has not yet been proven scientifically, HEET will not cause any problems in your car engine even if you put a whole bottle in your gas tank. It should therefore not give you any cause to worry unless the problem is more than you can handle.

Too Much HEET Vs Car

Putting excess HEET in your gas tank will not damage your car engine unless you used the one that is not meant for the engine. If you use the right HEET for the right engine it will not cause any problems to your car engine because it was designed to help it.

For example, the HEET that comes in a yellow bottle is the normal HEET. This brand of HEET is meant for 4-stroke gasoline engines. If you use this brand of HEET on 2-stroke or diesel engines, it may cause a problem in the engine.

However, you will not compare the problem it will cause in the engine to the problem some other thing that finds its way into the gas tank will cause. Pour out all the gas in the tank and replace it with a new gas if your car engine falls victim.

In Summary

When you put HEET into your gas tank, I can assure you that it is safe for your car engine, and the chances of overusing it are low. The chances of your car engine being damaged by excess HEET are as well low. If the quality of HEET in your gas tank is more than the quantity of gas in it, it will only affect the engine’s performance. You only need to put more gas in the tank to dilute the excess HEET.

As long as HEET is made to remove water from your gas tank, I make bold to say that it will not cause any damage to your car. On the other hand, excess of it in your gas tank will affect the performance of your car engine because it is not fuel.

Do not fail to use HEET according to the manufacturer’s instructions. That is the only way you will maximize the benefits of the product and prevent a such mistake from coming up again.

FAQs

Will HEET hurt my engine?

When you use HEET according to the manufacturer’s instructions, it will not harm your carburetor or fuel system.

Is it safe to put HEET in your gas tank?

You need one bottle of HEET or ISO-HEET to dilute 20 gallons (75.7 L) of gasoline. Do not use more than 2 bottles in a gas tank that has a capacity of  20-gallon (75.7 L). Dilute 30-gallon (113.6 L) of gas with 3 bottles of HEET. You can use HEET and ISO-HEET brands in any tank in any season of the year.

What does HEET do to gasoline?

With HEET in your gas tank, no water will freeze, it will rather absorb all of it. There will be no water in the tank again to block the free flow of gas through the gas line and fuel pump. When you start the engine, additives, methanol, water, and gasoline are burnt in the engine during combustion.

Do you put HEET in before or after gas?

Either way,  adding HEET before or after you fill your tank with gasoline works equally well.

Before you start the repairI'm a homeowner who does his own small-engine work, not a certified technician. Before any repair, pull the spark plug wire and let the engine cool. Anything involving blades under a raised machine, fuel system leaks or transmission internals — if you're not sure, have a dealer or small-engine shop look at it.
Jeff Mercer

Written by

Jeff Mercer

Hi, I'm Jeff. I look after about an acre of lawn, a riding mower, a zero-turn, a push mower that is older than some of my neighbours' cars, and a snowblower that only ever breaks the night before a storm. Doing my own repairs started as a way to save on dealer labour and turned into the part of yard work I actually enjoy.

GardenTooly is where I answer the questions people type into a search bar while standing next to a machine that won't behave: why the deck shakes, why the mower dies when it warms up, whether a bent blade shaft can be straightened, what the difference between two transmissions really means for you, and which fuel additive is worth the shelf space.

I'm not a certified small-engine technician and I don't sell equipment. Where I've done a job myself, I say so. Where an answer comes from the owner's manual, a service bulletin or a mechanic who knows more than me, I say that instead — and anything involving blades, fuel, jacked-up machines or a hydrostatic transmission gets a plain "take it to a shop" when that's the right call.