Ray's Chevy Restoration Site


Delco-Remy 10MT Starter Info


This page contains information about the Delco-Remy 10MT starter that was commonly used on Chevrolet gas engines from 1956 up into the 90's. The 10MT starter was also used on a variety of other GM and non-GM vehicles and equipment.

There are two basic versions of the motor itself (low and high torque) as well as numerous different drive-end nose pices to fit various applications. This page shows the 5 most common nose pieces used on Chevrolet engines from the mid 50's into the 70's.


Low and High Torque Versions:

The low torque version of the 10MT motor has the solenoid screwed directly to the metal strap that leads inside the starter motor to the brushes. An example of this type of starter is shown on the left in the above photo.

The high torque version of the 10MT motor has a spacer bushing and a long screw connecting the solenoid to the metal strap leading inside the motor to the brushes. An example of this type of starter is shown on the right in the above photo.

Solenoid Information:

The solenoids used with these starters serve a dual purpose. They (1) have a set of high current contacts that feed battery power to the motor. And they (2) pull on a plunger that is in turn connected to a shift fork that moves the pinion gear outward to engage it with the ring gear on the flywheel or flexplate.

Solenoid Connections:

Terminal Thread Size Connections / Usage
B 3/8" - 16 Positive battery cable. Some vehicles also have an additional wire or two (usually red and protected with a fusible link) connected to this stud to feed power to various other circuits.
S #8-32 Wired to the ignition switch "SOL" terminal. This connection is often made with a purple colored wire. On many vehicles, the connection runs through a clutch safety switch (manual trans) or a park/neutral safety switch (auto trans).
R usually #10-32
sometimes #8-32
Used to bypass the ballast resistor (or resistance wire) to feed ful battery voltage to the ignition system for a hotter spark during engine cranking. This terminal is not needed with HEI ignition systems since they do not use a ballast resistor or resistance wire. As a result, many 1975-up solenoids do not have an "R" terminal.
M 3/8" - 16 (outside)
#10-32 (inside)
Connected directly to the motor via a screw. See low/high torque motor differences above.

Common Chevrolet Drive-End Nose Pieces:

Shown below are five of the most common drive ends used on Chevrolet engines. These nose pieces can be used with either the low or high torque 10MT motors.

Cast Iron, Bolts to Bellhousing

This style of drive end is used on early manual transmission applications where the starter bolts to the bellhousing. I think it may have also been used on some early automatic transmissions such as the cast iron Powerglide where it bolted to an adapter plate between the engine and transmission.

I believe this style was last used in Chevy cars in the early/mid 60's but continued to be used in pick-up trucks up until 1972.

It attaches with 3 bolts. Two 3/8"-16 x 1" long bolts go through the two un-threaded holes in the starter nose and screw into the bellhousing. One 3/8"-16 x 1-3/4" long bolt goes through an un-threaded hole in the bellhousing and screws into the threaded hole in the starter nose.


Cast Iron, 2 Bolts to Engine Block

This style of drive end is used on later manual transmission applications where the starter bolts to the engine block. It is used with a 14" diameter, 168 tooth flywheel. It will also fit automatic transmission applications using a 14" diameter, 168 tooth flexplate.

It attaches with 2 equal length bolts in a staggered (one farther ahead than the other) pattern. Both bolts are 3/8"-16 x 3-5/8" long and feature special knurled shanks to ensure a snug fit in the holes.

Also shown in the photo is an example of the type of shim that is sometimes needed with this style of starter nose. See "Starter Shimming" section near the end of this page for details.


Cast Iron, 3 Bolts to Engine Block

This style of drive end is used on many 348, 409, and early big block applications that don't use the bellhousing mounted starter. I believe it was also used on a few small block applications from the mid 60's and into the early 70's. These were used with both manual and automatic transmissions having a 14" diameter, 168 tooth flywheel or flexplate.

This drive end is very similar to the 2-bolt cast iron nose shown above except for the additional bolt hole. It uses two of the same size 3/8"-16 x 3-5/8" knurled shank bolts as the 2-bolt iron nose. The additional hole takes a 3/8"-16 x 3" bolt without the knurled shank.

Note: I don't think the 3rd hole on this style nose will line up with the bolt pattern on some engines. Shimming might sometimes be needed with this nose. See "Starter Shimming" section near the end of this page for details.


Aluminum, 2 Bolts to Engine Block, Straight Across

This style of drive end is used on most automatic transmission applications using a 12-3/4" diameter, 153 tooth flexplate. It might also be used on manual transmission applications using a 12-3/4" diameter, 153 tooth flywheel.

It attaches with two mounting bolts in a straight across pattern. The long bolt in closest to the engine is 3/8"-16 x 4-5/8". The short outboard bolt is 3/8"-16 x 1-7/8". Both bolts have knurled shanks to ensure a snug fit in the holes.

Not shown in this photo is the style of shim (straight style) that is sometimes needed with this nose. See "Starter Shimming" section near the end of this page for details.


Aluminum, 2 Bolts to Engine Block, Staggered Pattern

This style of drive end is used on most automatic transmission applications using a 14" diameter, 168 tooth flexplate.

It attaches with 2 equal length bolts in a staggered (one farther ahead than the other) pattern. Both bolts are 3/8"-16 x 4-5/8" long and feature special knurled shanks to ensure a snug fit in the holes.

Also shown in the photo is an example of the type of shim that is sometimes needed with this style of starter nose. See "Starter Shimming" section near the end of this page for details.


Starter Braces:

Many applications use a brace to support the forward end of the starter motor. These braces are commonly left off when starters are replaced, but should always be re-installed to prevent cracked nose pieces (especially with the aluminum ones).

The photo above shows a typical starter brace installation. Always tighten the starter mounting bolts before tightening the brace nut/bolt.

Starter Shimming:

With the engine block mounted starters, it is sometimes necessary to add shims between the block and starter for proper pinion to ring gear spacing.

Clearance from the tip of a pinion tooth to the root of the ring gear should be in the 0.020 to 0.035" range. A paper clip (about 0.035" diameter) makes a good feeler gauge. Disconnect the battery and use a screwdriver or small pry bar to hold the pinion gear into the engaged position. Or remove the solenoid and pull the plunger to engage the pinion for measuring.

If the clearance is too small, it can be increased by adding a full length shim (such as the ones shown in some of the above photos) to move the starter farther away from the flywheel/flexplate. These shims are available in several different thicknesses.

If the clearance is too large, it can be decreased by adding a small shim between the starter and engine block only at the outboard bolt location.



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