No Products in the Cart
Caterpillar 557-7633 is the hydraulically actuated (HEUI type) fuel injector with a yellow solenoid cap and two pin connector, a hold down flange with two bolt holes, red and black O rings and a black nozzle body. It is used on Caterpillar C9 engines (330D, 340D, 140M). This aftermarket version is made to the same mounting and connections as the original, so it fits where the old one came off.
The same part is also sold as Caterpillar 20R-8968 and Caterpillar 20R-8064.
Sold as one unit. Check the number on your old part, or in the parts manual for your machine, before ordering.
| Part Type | Fuel Injector |
| Replaces | Caterpillar 20R-8968 |
| Injector type | Hydraulically actuated electronic (HEUI type) |
| Engine | Caterpillar C9 |
| Machine | Caterpillar 330D, 340D, 140M, 14L, 160M, 2390, 2491 |
| Cross references | Caterpillar 557-7633, Caterpillar 20R-8064 |
| Fits | the Caterpillar C9 diesel engine, including the 330D and 340D excavators, 140M, 14L and 160M motor graders and 2390 and 2491 feller bunchers |
| Condition | New, aftermarket |
| Stat. HS-Code | 840999 |
| Country of Manufacture | China |
Machines
Check the part number on your old unit before ordering.
| Caterpillar Part No.(SPM Part No.) | Fits |
|---|---|
| 20R-8968 / Caterpillar 557-7633 / Caterpillar 20R-8064(SPM-HEP-4891) | the Caterpillar C9 diesel engine, including the 330D and 340D excavators, 140M, 14L and 160M motor graders and 2390 and 2491 feller bunchers |
| Brand | Part No. |
|---|---|
| Caterpillar | 20R-8968 |
| Caterpillar | 557-7633 (this page, SPM-HEP-4891) |
| Caterpillar | 20R-8064 |
All of these numbers are the same part.
What it does
It sprays a metered charge of fuel into the cylinder at the right moment. Spray pattern and opening pressure decide how cleanly the engine burns its fuel.
Where it is used
Made for the Caterpillar C9 diesel engine, including the 330D, 340D excavators, 140M and 4 more. The full list is in the tables above.
We check what other aftermarket sellers charge for this same part. Their prices on the date we checked:
| Seller | Price | Checked |
|---|---|---|
| eBay (5 aftermarket sellers) | USD 330.50 to 346.99 | 1 Nov 2026 |
| SINOCMP | USD 369.00 | 1 Nov 2026 |
| Buy Machinery Parts | USD 424.50 | 1 Nov 2026 |
| FridayParts | USD 445.73 | 1 Nov 2026 |
| Fab Heavy Parts | USD 467.71 | 1 Nov 2026 |
| WDPart | USD 658.00 | 1 Nov 2026 |
| Diselmart | USD 765.00 | 1 Nov 2026 |
| Spare Part Mart | USD 264.40 | Today |
Our price of USD 264.40 is 20% to 65% less than these sellers.
Found this part cheaper somewhere else? Send us the listing and we will beat it by 5% under our Price Beat Guarantee. Every order is also covered by our 30 day money back guarantee.
Yes, it was made for the Caterpillar C9 diesel engine, and 7 more listed under compatible equipment. Check the old fuel injector is marked 557-7633 or one of the cross references, because makers change parts between serial ranges.
On the Caterpillar C9 diesel engine, often 5,000 to 10,000 hours, but much less on poor or wet fuel. Injectors are usually changed when they fail a test, not by hours.
Black or white smoke, a misfire or knock on one cylinder, hard starting, higher fuel use, or a high return leak or balance rate on test.
Always. Fit a new copper washer and O-rings under every injector you remove. A reused washer leaks combustion gas and carbon packs the bore.
Run a return leak test or read the injector balance rates with a diagnostic tool. On older mechanical engines, cracking each pipe in turn at idle shows which cylinder changes least.
No. It is an aftermarket fuel injector made to replace the Caterpillar 557-7633. It is not made by the original manufacturer; the number only shows what it replaces.
Live rates for the quantity selected, delivered to your door. Confirmed at checkout.
Join and we put 200 points on your account, worth $10 off an order over $75 USD. Then a point for every dollar you spend after that. Turn points into a discount whenever you like.
Opens the Marty Mates panel. No password: you enter your email, we send a code, and that is you in with your 200 points waiting. Joining signs you up to our emails and you can leave any time from the link in any of them. See our terms and conditions.
Member deals, specials before they go public, and easy ways to stack up points. Plus a nudge when a part you bought is due, so you are not caught out mid job.
You can leave any time from the link in any email we send. See our terms and conditions.
We will only bother you when it is worth it: a member deal, a specials drop, a way to earn points faster, or a heads up that a part you bought is due.
Join Marty Mates and we put 200 points on your account, worth $10 off an order over $75 USD. Then a point for every dollar you spend after that.
No password: you enter your email, we send a code, and that is you in.
