Partner 5000 Plus Fuel Mix (Ratio Chart)
For the Partner 5000 Plus, use the fuel ratio printed in the matching saw manual or on its fuel label. If that specification is 50:1, mix 20 mL of suitable air-cooled two-stroke oil with each 1 L of gasoline, or 2.6 US fl oz per US gallon. Do not guess a different ratio: versions and service parts may differ.
A dull chain can make a sound saw feel weak, but the wrong fuel mix can cause serious engine damage. Before you head out, check the fuel label and manual, then measure the oil rather than estimating by eye. This guide gives you the mix calculations and the checks that help avoid a costly mistake.
In the shop, I start with the saw’s own markings, not a ratio remembered from another machine. A model name alone does not confirm the fuel ratio, bar, chain, or carburetor settings. If the manual is missing, identify the saw from its type plate and find the matching manual before mixing.
Partner 5000 Plus fuel mix chart
This chart shows the oil amounts for common gasoline-to-oil ratios. It is a measurement aid, not a list of approved settings for your saw. Use only the ratio specified by the matching Partner manual or fuel-cap label, and use oil suitable for air-cooled two-stroke engines.
| Gasoline-to-oil ratio | Oil per 1 L gasoline | Oil per 5 L gasoline | Oil per 1 US gal gasoline |
|---|---|---|---|
| 50:1 | 20 mL | 100 mL | 2.6 US fl oz |
| 40:1 | 25 mL | 125 mL | 3.2 US fl oz |
| 32:1 | 31.25 mL | 156.25 mL | 4 US fl oz |
| 25:1 | 40 mL | 200 mL | 5.12 US fl oz |
A ratio such as 50:1 means 50 parts gasoline to 1 part oil by volume. For a 50:1 mix, the quick calculation is 1,000 mL of gasoline divided by 50, which gives 20 mL of oil. The US-gallon figure uses a US gallon, not an Imperial gallon.
Which ratio should I use?
The correct ratio is the one specified for your particular saw, not the one that appears most often in a chart. Use 50:1 only if the applicable manual or fuel-cap label calls for it. If those sources specify another ratio, follow that instead.
If the label is missing or you cannot match the manual to the saw’s type plate, pause before refueling. Do not choose 50:1 simply because it is a common mix ratio. A dealer or service shop may be able to help identify the correct manual from the saw’s markings.
How to mix fuel accurately
Accurate measuring means using a graduated fuel-safe container or oil measure to add the specified amount of two-stroke oil. A household cup or an unmarked bottle can make it easy to add too little or too much. Mix only in an approved fuel container, away from flames, sparks, and other ignition sources.
- Confirm the ratio on the matching manual or fuel-cap label.
- Check that the gasoline is fresh and suitable under the fuel and saw manufacturers’ instructions.
- Measure the gasoline and the matching amount of air-cooled two-stroke oil.
- Combine them in an approved container and mix as directed by the fuel or oil manufacturer.
- Mark the container clearly as mixed fuel and note the ratio and date.
Do not put straight gasoline into this two-stroke saw. Do not pour oil into the tank by eye. Either mistake can leave the engine with the wrong fuel mixture.
Fuel does not remain suitable forever. Follow the storage period stated by the fuel and oil manufacturers, and do not use fuel that is stale or water-contaminated. The allowable ethanol content cannot be confirmed for every saw version, so check the matching manual rather than relying on a fixed limit.
Worked mix amounts
These are examples of the arithmetic, not claims about which ratio applies to every Partner 5000 Plus.
- If the manual specifies 50:1 and you measure 2 L of gasoline, add 40 mL of oil.
- If it specifies 40:1 and you measure 3 L of gasoline, add 75 mL of oil.
- If you need only 1 L of fuel, measure the matching oil amount from the chart; do not use a larger batch just to make measuring easier.
The ratio is based on gasoline volume. Use the same units throughout, and do not confuse millilitres with fluid ounces. A marked measuring bottle helps prevent that error.
Checks before starting the saw
A correct mix is only one part of safe preparation. Before starting, wear chainsaw-rated leg protection, a helmet with face and eye protection, hearing protection, gloves, and protective boots. Check the saw’s manual and applicable workplace rules for any additional requirements.
With the engine off, inspect the chain, guide bar, fasteners, handles, chain catcher, throttle lockout, and chain brake for damage or loose parts. Confirm that the chain is properly tensioned according to the chain or saw instructions. Stop if a safety part does not work as intended.
Refuel with the engine stopped and cool, away from ignition sources. Start the saw using the manual’s procedure on stable ground, with the chain brake engaged. Before cutting, verify that the engine idles without driving the chain and that the brake operates as described in the manual.
Fuel-mix scenarios: avoid the common mistakes
These examples show how I would work through typical garage decisions. They are practical scenarios, not a substitute for the saw’s manual.
You have a 50:1 label and one litre of gasoline. Measure 20 mL of suitable two-stroke oil, mix it with the gasoline in an approved container, and label the container. Do not add extra oil “for protection” unless the saw manufacturer specifies a different ratio.
You have an unlabeled can of fuel. Do not assume its ratio or age from its color or smell. If you cannot verify what is in it, set it aside and prepare a fresh, correctly measured batch. Mixing unknown fuel into a known batch makes the final ratio uncertain.
The saw runs poorly after refueling. Stop cutting and check the fuel source, mix ratio, fuel condition, and the saw’s manual. Do not compensate by turning carburetor screws at random. Model designation alone does not establish carburetor settings or engine speed.
Bar, chain, and sharpening checks
Fuel ratio does not tell you which bar or chain fits. Confirm the bar length, chain pitch, gauge, and drive-link count from the bar markings and the saw’s fitted sprocket, then match replacement parts to those specifications. Do not infer these details from “5000 Plus” alone; replacement bars and production versions may differ.
Pitch describes the chain size used with a matching sprocket. Gauge is the thickness of the chain drive links that fit in the bar groove. Drive-link count is the number of links that run around the bar. All must match the saw setup.
For sharpening, use the file size and filing angles specified by the chain manufacturer for that exact chain. There is no safe universal file size or angle to infer from the saw model alone. Set depth gauges, also called rakers, to the chain maker’s specification. If the chain burns wood, makes fine dust, or needs force to cut, stop and inspect it rather than pushing harder.
Use dedicated chainsaw bar-and-chain oil in the separate oil tank. Its purpose is to lubricate the chain and bar; it is not two-stroke engine oil and should not be mixed into the gasoline. Check the oil level and follow the manual’s maintenance instructions. A universal oil viscosity or pump-flow figure cannot be given without the specific setup and conditions.
Cutting, shutdown, and storage
A sharp, correctly tensioned chain reduces the need to force the saw through wood. Maintain a firm two-handed grip, stable footing, and a clear work area. Keep the guide-bar nose’s upper quadrant away from wood: contact there can cause rapid kickback toward the operator. A chain brake can reduce risk, but it cannot make unsafe technique safe.
Plan for the wood to move as it is cut, especially where it may be under stored tension. Do not cut above shoulder height or use the bar tip as a shortcut. Felling and complex tree work require suitable training and methods; use qualified help when the work is beyond your skill.
Before setting the saw down or making an adjustment, engage the brake and stop the engine. Let the saw cool before cleaning. Check the chain tension, bar rails, air filter, and visible parts for damage, then store the saw and fuel as directed by their manufacturers.
Key takeaway: verify the ratio first, measure the mix, and stop if the fuel or saw specification is uncertain. Do not try to solve a dull-chain problem by changing the fuel ratio.
Frequently asked questions
What is the fuel ratio for a Partner 5000 Plus?
Use the ratio shown in the matching manual or on the fuel-cap label. Use 50:1 only when that source specifies it.
How much oil goes into 1 L of gasoline at 50:1?
Add 20 mL of suitable air-cooled two-stroke oil to 1 L of gasoline.
How much two-stroke oil goes into one US gallon at 50:1?
Add 2.6 US fl oz of oil per US gallon of gasoline.
Can I use straight gasoline?
No. This is a two-stroke saw and requires the specified gasoline-and-oil mix. Straight gasoline can cause severe engine damage.
Can I use 40:1 instead of 50:1?
Only if the matching manual or fuel label specifies 40:1. Do not substitute ratios based on advice for another saw.
What if the fuel-cap label and manual differ?
Do not guess. Confirm that the manual matches the saw’s type plate and ask a Partner service source or qualified dealer to resolve the discrepancy.
Can I use old mixed fuel?
Use it only within the storage period stated by the fuel and oil manufacturers. Do not use stale or water-contaminated fuel.
Does the model name confirm the bar and chain size?
No. Match bar length, pitch, gauge, and drive-link count to the bar markings, sprocket, and saw instructions.
Should bar oil go into the fuel tank?
No. Put dedicated bar-and-chain oil in its separate tank. Keep it out of the gasoline-and-oil mix.
(This article was written by one of our staff writers, David Hensley. Visit our Meet the Team page.)
