| Also known as | S1875 |
| Diagram | Fig. 5 — CYLINDER BLOCK AND HEAD TR7RV · ref 34 |
| Subsystem | engine top |
| Listed in parts books | 1970–1971, 1974, 1976–1980, 1985 |
BOLT 1/4X20 2UH ROCKER BOX
1/4x20 bolt for the outer rocker box corner on unit twin cylinder heads.
This is the bolt that holds the outer rocker box down at the corners on the cylinder head, showing up in the catalog under cylinder block and head listings for the T120R and TR6R/TR6C. It's a 1/4x20 bolt, and the catalog calls it out specifically for the rocker box corner position rather than a generic head fastener.
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On the older letter-prefix system this same bolt was known as S1875, and it also shows up under the industrial equivalent number 91247A550 if you're cross-shopping a hardware supplier. These bolts get run down snug against a washer under the head, and since they sit right out in the open on top of the motor, they're an easy thing to check for wear or a stripped corner when you've got the rocker boxes off.
We usually see these ordered a few at a time since there's more than one per rocker box - if you're doing a full gasket job up top it's worth grabbing extras so you're not stopping mid-job over one tired bolt.
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