Jordan, Presiding Judge.
The plaintiff appeals from the overruling of his motion for a new trial, after verdict and judgment for the defendant, asserting error on the jury instructions regarding negligence rules as given or omitted. Held:
1. There was some evidence which would have authorized the jury to determine by inference that the defendant’s servant negligently failed to fill the radiator of a truck engine, after replacing a defective heater hose, which caused the engine to overheat, and that the plaintiff driver, upon raising the hood, over the engine to investigate the cause of steam or smoke escaping, may have negligently hit the radiator cap, causing it to come off, and that the combined negligence of the defendant’s servant and the plaintiff could proximately have caused the plaintiff’s injuries. The plaintiff was burned by steam or hot *491fluid from the radiator immediately after he opened the hood. The defensive pleadings included allegations that if the defendant was negligent, the plaintiff was also negligent, and that the negligence should be compared. The trial judge failed to instruct on comparative negligence, and the plaintiff duly objected to this omission at the close of the instructions and before the jury returned a verdict. Under the circumstances here shown we think the trial judge erred in failing to give the jury instructions on the rules for comparing the negligence of the defendant’s servant and the plaintiff, in the event the jury should find that both were negligent in proximately causing the plaintiff’s injuries. See Ga. L. 1968, pp. 1072, 1078 (Code Ann. §70-207 (a)); Code §105-603; Crafton v. Livingston, 114 Ga. App. 161 (2) (150 SE2d 371); Whatley v. Henry, 65 Ga. App. 668, 674 (16 SE2d 214); Southern Express Co. v. Hughes, 23 Ga. App. 224 (97 SE 860).
Argued September 14, 1971
Decided September 30, 1971.
C. Lawrence Jewett, for appellant.
Hurt, Hill & Richardson, Robert R. Richardson, Sam E. Thomas, for appellee.
2. The remaining contentions are without merit.
Judgment reversed.
Quillian and Evans, JJ., concur.