Craftsman 3.7 vs Poulan 3700 Saw (Tear Down)
The Craftsman 3.7 and Poulan 3700 may share a design lineage, but their names do not prove they are the same saw. Identify each saw by its complete model and serial number, then compare parts and service documents before teardown. Inspect and measure components separately; do not assume shared parts, fuel mix, bar fit, or carburetor settings.
If you are deciding whether one saw can donate parts to the other, the expensive mistake is to trust a badge or a familiar-looking case. A correct identification and careful teardown can save money over time by preventing wrong parts orders, repeat repairs, and damage from incorrect tuning.
In the shop, I treat these as two individual machines until their identification and components show otherwise. “Craftsman 3.7” may refer to an engine-size description rather than a complete model number. Poulan 3700 identifies a model name associated with the 3.7-cubic-inch class, about 60.6 cc, but the label and engine configuration on the saw still need checking.
Equipment Identification, Setup & Safety Prep
This section establishes what each saw is before parts are removed. Model and serial details, component markings, and matching service documents are more reliable than color, decals, or apparent size. Identification comes first because saws with similar names or housings may differ in critical parts and setup.
Record identity before comparing parts
Find the identification plate or label on each saw and photograph it clearly. Record the full model number, serial number, and any other stamped or printed codes. Do not treat “3.7” as a complete model number unless the manufacturer documentation identifies it that way.
Serial-number formats can vary by maker, model, and production period. I would not infer a precise manufacturing date or factory from a number alone. Check it against a parts list or manual for the exact model, or ask a knowledgeable parts source to confirm the record. A missing label is a reason to slow down, not to guess.
| Check | Craftsman saw | Poulan saw | What confirms a match |
|---|---|---|---|
| Full model number | Record from label or stamping | Record from label or stamping | Exact model appears in manual or parts list |
| Serial number | Photograph and transcribe | Photograph and transcribe | Traceable through reliable manufacturer or parts records |
| Cylinder and crankcase | Record casting marks and shape | Record casting marks and shape | Matching documented assembly or part number |
| Ignition and carburetor | Record maker and markings | Record maker and markings | Manual or parts list supports that component |
| Clutch, oil pump, bar mount | Photograph and note details | Photograph and note details | Verified part numbers and mount pattern |
A matching displacement or exterior shape is not enough to establish interchangeability. Compare the cylinder and crankcase, ignition, carburetor, clutch, oil pump, and bar-mount pattern. Even if a few parts match, that does not prove the full platform is shared.
Make both saws safe and keep them separate
Before opening either saw, drain fuel and bar oil into suitable approved containers. Disconnect the spark-plug lead, wear eye protection and cut-resistant gloves, and work on a clean, stable bench. Keep each saw’s parts in its own labeled tray. Photograph fuel lines, wiring, and hardware routing before disturbing them.
The chain brake should be engaged while handling a saw, but do not rely on it as a substitute for safe handling. Keep the chain away from your body, and do not start either saw indoors. Use the exact service documentation for removal steps and tool requirements.
Teardown, Maintenance, Sharpening & Tuning
A controlled teardown compares condition and documented parts, not just appearance. Work in stages, record what comes off each saw, and measure only against specifications for that exact model. If the documentation is missing, pause before settings or reassembly steps that depend on factory values.
Inspect before opening the engine
Start with visible wear and damage. Check bar rails, sprocket, chain catcher, chain brake, anti-vibration mounts, fuel lines, impulse line, tank vents, oil passages, and crankcase for cracks or leaks. Note loose fittings and missing hardware. A worn external part can explain poor operation without requiring an engine teardown.
Next, remove covers and components in the sequence shown by the correct service manual. Use the proper flywheel and clutch tools. Do not strike the crankshaft with an impact tool or pry against sealing surfaces; either approach can damage parts that may be hard to replace.
Compare internal condition, not just dimensions by eye
With the cylinder accessible, inspect the piston, rings, cylinder wall, bearings, and seals. Record visible scoring, wear, or damage, and take measurements only with suitable tools and a service limit for that model. A piston that looks similar to the other saw’s is not proof that it fits or is serviceable.
Inspect the carburetor for its maker, model markings, and diaphragm condition. Record ignition parts and oil-pump details before ordering replacements. A carburetor that bolts on may still have different internal calibration or fit. Keep parts labeled by saw until reliable documentation confirms an interchange.
| Teardown finding | What it may indicate | Safe next step |
|---|---|---|
| Scored piston or cylinder | Possible lubrication, air leak, or overheating problem | Inspect fuel delivery and seals; confirm repair limits in the manual |
| Cracked, stiff, or loose fuel line | Fuel supply fault or air entry | Replace only with correct parts; inspect related connections |
| Damaged bar rails or worn sprocket | Poor chain tracking or accelerated wear | Match replacements to the documented mount and chain system |
| Carburetor markings differ | Different component or calibration | Identify each carburetor before adjustment or substitution |
| Oil passages blocked | Reduced chain lubrication | Clean and test by the manual’s method |
This is where teardown comparisons can prevent waste. For example, if one saw has a sound top end but a damaged oil pump, it may be a better repair candidate than a second saw with cylinder damage. That is a decision based on observed condition and confirmed parts availability, not on which decal looks more valuable.
Reassemble and tune only from exact documentation
Do not use one general fuel ratio for both saws. Vintage and later versions can have different oil requirements. Follow the exact model’s manual for the fuel mix and oil type. Likewise, do not assume a chain pitch, gauge, drive-link count, bar length, fastener torque, raker clearance, oil-pump setting, or carburetor RPM from the names alone.
A saw that starts and revs freely is not necessarily tuned correctly. An unverified high-speed setting can cause a lean seizure or overspeed. Do not use carburetor screws to mask a suspected air leak, blocked fuel path, or incorrect carburetor. If tuning is needed, pressure- and vacuum-test the crankcase and fuel system, then use the manual’s procedure and a tachometer.
Field Cutting and Landscaping Operation
A cutting test is useful only after identification, inspection, and repair are complete. This section explains what to verify before judging either saw in wood. Safe performance depends on a sound machine and a correctly matched bar and chain, not on the displacement number alone.
Verify the cutting equipment
Read the bar stamp and chain markings. Confirm pitch, gauge, drive-link count, and bar mount against the exact saw’s manual or parts information. Do not assume that a 3/8-inch chain, .050-inch gauge, or any particular bar length fits either saw simply because it is common on another model.
Use only a bar within the manual-approved range. Wood species, diameter, condition, and operator skill also affect whether a setup is suitable. Never test with an unverified combination or a disabled chain brake.
Before a controlled outdoor test, verify throttle return, brake function, chain tension, and oil delivery using the manual’s prescribed check. Fill with the documented fuel mix and bar oil. If the saw leaks, will not idle reliably, or has an uncertain brake or lubrication system, do not cut with it.
A practical comparison should use the same sound bar-and-chain setup only if it is confirmed compatible with both saws. Otherwise, compare each with its own verified equipment and record the difference. Do not treat different bars, chains, sharpening, or wood as proof that one engine is stronger.
Shutdown, Storage & Seasonal Care
A teardown is not complete until the saw is safely tested, cleaned, and stored. This section covers the final checks that help protect the repair and make later diagnosis easier. Keep records with each saw so future parts decisions do not depend on memory or an uncertain label.
After testing outdoors, shut the saw down and let it cool. Recheck for leaks, loose parts, chain damage, and signs of poor lubrication. Clean debris from the cooling area and oil passages as directed by the manual. If tuning or oil delivery is uncertain, stop and resolve it before further use.
For storage, follow the exact manual’s fuel and preparation instructions rather than applying one rule to both saws. Keep the model and serial photographs, parts invoices, measurements, and service notes together. This record is especially useful if a replacement carburetor or ignition part later appears to fit but has not been verified.
What the teardown can and cannot prove
An observed teardown can establish the condition of the parts in front of you. A documented part-number match can establish that a specific replacement is listed for a model. Neither similar appearance nor shared displacement alone proves that the Craftsman and Poulan are mechanically equivalent.
If you cannot find reliable documentation, use a repair shop or parts specialist familiar with older saws. Ask them to verify the complete model number and the specific assembly, not simply confirm that the saw is “a Poulan type.” That small step can prevent a costly, unsafe mismatch.
FAQ
Are the Craftsman 3.7 and Poulan 3700 the same saw?
The names alone cannot confirm that. Compare full model numbers, parts lists, and key assemblies before treating them as the same platform.
Does “Craftsman 3.7” identify a unique model?
Not necessarily. It may describe engine displacement. Find and record the complete model number on the saw.
How much displacement does Poulan 3700 indicate?
The name is associated with the 3.7-cubic-inch class, about 60.6 cc. Confirm the identification and configuration of the specific saw.
Can I use a Poulan 3700 part on a Craftsman 3.7?
Only when the exact part number or service documentation confirms compatibility. Similar shape or mounting is not enough.
Can both saws use the same fuel mix?
Do not assume so. Use the fuel ratio and oil type stated in each saw’s exact manual.
What bar and chain fit these saws?
The names do not establish a safe setup. Check the manual and verify bar mount, chain pitch, gauge, drive links, and approved bar range.
Can I use one saw’s carburetor settings on the other?
No, not without model-specific documentation. Use the correct manual and a tachometer; incorrect tuning can damage the engine.
What should I inspect first during teardown?
Record the model and serial numbers, then inspect external safety and fuel and oil systems. Photograph routing before removing parts.
Is a saw safe to test if it starts and revs?
Not by that fact alone. Confirm brake, throttle return, chain fit, oil delivery, and correct tuning before cutting.
What if the serial number or label is missing?
Do not guess from the decal. Record casting and component marks, compare them with reliable parts records, or have a qualified parts source identify the saw.
(This article was written by one of our staff writers, Elliott Fowler. Visit our Meet the Team page.)
