Generac — Check Engine Compression
Testing & diagnosis
From a Generac service manual covering: Craftsman 2200i C0010020, Craftsman 3000i C0010030, GP2200, GP3000i, GP3500iO, IQ3500, PRO-3000i INV3000DMN, Premier 2200i INV2200DMN, iQ2000, iQ3500, iX 1600, iX 2000…. Check it applies to your exact model before use.
Applies to: Generac GP3000i, Generac GP3500iO, Generac IQ3500, Generac iX 1600, Generac iX 2000
Procedure
- Remove spark plug.
- Insert an automotive type compression gauge into spark plug hole.
- Crank engine until there is no further increase in pressure; record highest reading.
Tools required
- compression gauge Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Minimum allowable compression pressure cold engine: 60 psi
- Note: due to decompression system on iQ2000, compression test will not be valid (typically about 5 PSI)
Full service-parts list: Generac GP3000i →, Generac GP3500iO →, Generac IQ3500 →, Generac iX 1600 →, Generac iX 2000 →
Source: Generac service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.