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Swap your '216 Chevy "6" for a '235

If you own a '37-'53 early Chevy car or truck with a "splash oiling" '216 or '235 engine, and want a smooth, powerful daily "driver", installing the later full-pressure '235 is the answer.

This new design was first installed in '53 passenger cars with PowerGlide, thereafter in all models and sizes
(passengers and commercial)

Not only does the swap happen easily, without butchering or modification, it brings improved performance and reliability from full-pressure oiling, insert rod bearing, and lighter-weight aluminum pistons not to mention improved breathing, thanks to larger intake valves and ports.

Read on for the simple installation tips and identification clues to help you score the right engine: This is one swap "made in heaven"

  1. The rear of every Chevy '6' block ('216, '235, or '261) is the same from 1937 through 1962! And, the flywheel/crank-flange pattern is the same from '40-'62! We obviously have wonderful interchangeability. Therefore, using pure Chevy parts, any engine from '37-'62 can be installed into any chassis (car, truck, etc.) from '37262!
    You will however, need to pick the right parts: here's how....

    Whenever you're putting the donor engine into ('41-'53), re-use your original bell-housing, flywheel, and starter. This means your rear motor-mounts remain unchanged. '37-'40 installations will need to get a '41-'54 wide-tooth (#139) 6-bolt flywheel off any '216, '235 or '261; then, use their original bell- housing starter. The 6-volt starter is just fine, even if you're converting to 12-volts; it'll love it!
    (Final Note of Caution: The fine-tooth (#162) '55 and later flywheel will not mesh with your original starter! Do not use it.)

    *'37 chassis (Pass or comm.) are all alone in (3) additional requirements:

    1. must obtain a '41-'54 throwout arm (and pivot ball).
    2. replace throwout thrust washer with a '41-'62 throwout bearing, and
    3. obtain and install a transmission throwout bearing retainer from '38 or '39 Chevy transmission.

  2. Pre-'49 cars and trucks will have to slightly alter the exhaust pipe to fit the '235 manifold. (Nice time to install "duals", isn't it? Hint. Hint.) By the way, '216/'235 exhaust/intakes won't mix and match. And, although the entire '216 manifold set can be bolted to the 235 involved, it's a bit Mickey Mouse since the port rings will have to be eliminated due to the '216s smaller port size.

  3. If your "new" '235 has the big water-temp. hole, ask NAPA for Balkamp part #701-1798 (Weatherhead calls it part # 202x5x4). Now, your original temp. sender fits.

    Let's solve the "hydraulic or solid lifter question" now... "Solids' were the rule on every Chevy '6' through 1949 (either '216 or '235 "Loadmaster"). Between 1950 and 57. solids came with every commercial or "stick" (passenger) transmission, whether '216 or 235 or 261 engine. Hydraulics went only with PowerGlide equipped cars. From '58 to '62, every block was drilled for hydraulic lifters, though some had solids installed. (Hydraulic lifters will only function in a block that has the oiling passage drilled through the lifter bores) this hole will be plugged and visible on the rear of the block, just above the cam plug.

    (**special note: there are, currently, no satisfactory aftermarket hydraulic lifters available. So, we suggest you install a solid-lifter cam/lifter combo,)

    '58-'62 engines must use a lifter with chamfered sides to prevent shutting off rocker arm oil! No oil line from rear cam bearing to block-center will be found in the pushrod chamber of these engines; and, in addition to the I.D. criteria (above), will have a triangular side-mount pattern.

    Mention MUST be made of the Federal reduction of gasoline lead-content to .1gm/gal. begining January 1, 1985. This amount of lead additive is 1/10 of the amount your engine was designed for and, continued operation will effect exhaust valve seat life. Take the time, while you're building your engine, to have the no-lead exhaust valves and seats installed in the cylinder hear! (You'll do it sooner or later.) Call Patrick's for the parts.

  1. SPECIAL NOTE for all 1952 and '53 passenger. Your cars have a side-mount arrangement which will require locating a full-pressure block from either a '53 PowerGlide or (any '54) car or truck. (See add'l pics and details in eng. I.D. section).

    With a bit of perserverance, a 58-62 block can be installed, by modifying the 53-54 mount brackets. Using a 55-57 block will require reverting to '49-'51 mounting: front mounts and side mounts and brackets (the bolt on's at the bell-housing and axle brackets extending off the frame rails)

  2. Identifying the full-pressure you want to install: (Remember, you're looking for a '53 PowerGlide, or anything later.)

    1. Simply checking the style of the water pump will take care of about 90% of the prospects. If it has a pump whose entire body is below the head gasket surface, rather than half on the block and the upper half in front of the head, it's gotta he '55 (2nd) through '62. You've found it. The search is over. Disregard any of the next criteria.
    2. Check the rocker cover ("valve cover"). If it's held on with four (4) screws (2 on each side), it's a '54-'62 and the right one. Look no further- you just scored.
    3. Walk on by any engine with the tall pushrod cover that surrounds the spark plugs. It is a "babbit pounder".
    4. Also eliminate any engine with the little, tell-tale triangular plate and curved oil line in the middle of the driver's side. This tells you it has the dreaded dipper rods and splash oiling. The driver's side of the engine you want is ''clean" (no plate or line).
    5. Disregard any engine with the studs through the rocker cover, except one: the '53 P.G. (first year); but, it will be without the above plate and line, too.
    6. Want to pinpoint engine I.D.? On the block above the end of the starter will be an initial (A-L), followed by either (2) or (3) numbers. The initial represents the month: the numbers are the day and year the block was cast. Now, then, no more guessing!

  3. A note on front mount plates.. They will interchange on every Chevy '6' ('216, '235, or '261) built from 1937 thru '62! This matches the bellhousing story. It's another story, but the fronts and rears of every Chevy '6' are also the same as every GMC "small" '6' ('228, '236, '248, '256, '270, and '302)! Obvious why these were popular swaps!

  4. Throttle linkage may need modifying if your block's bellcrank mount hole is further back (toward firewall). Easy ... some of the curve will need to be taken out of the accelerator rod. Squeeze it in a vise 'till it makes it's travel without rubbing the floor pan (as installed in the bellcrank, without return spring). When that's done, measure how much it needs shortening by bringing the whole linkage assemble to "full throttle". Simply cut that amount out of the slender part of the rod and re-weld. Done!

  5. Front engine mount pad(s) should be installed on the engine before putting it between the fenders, since the pass. side bolt may only go into the mount with the timing cover and "harmonic balancer" removed. (See front mount hole in addendum, item #3)

  6. Water pump / generator alignments depend on each other. Install the water pump first. If your '235 wore the long water pump pulley, DO NOT BEGIN HACKING ON THE RADIATOR CORE SUPPORT and/or LATCH PANEL! Patrick's has the short pump and special pulley for only $139.95 This allows for the use of the larger, late-model fan, which provides better cooling.
    (Note: it is not correct to press the early '216 pulley onto the late water pump, since this spins the impeller approximately 190% of design speed. and may even cavitate the water, causing overheating. In addition, the old, back-woods method can literally be dangerous, since it requires using the '216 "low speed" fan which is turned far beyond its design safety.)

  7. Now, align the generator with the water pump pulley. If you wish to switch to an alternator at this point, Patrick's has the bracket set for only $59.95. (specify year.)

  8. Radiator Hoses and sizes. Upper hose may require re-use of your '216 thermostat housing. No sweat, bolt it onto the '235 cylinder head. Lower hose may need to be dual-size. Your neighborhood parts house has them available.

  9. Crankshaft Pilot Bushing. Check for the presence of this vital item if you're putting a "stick" trannie behind the later '235!
    (if the engine came with automatic, it may not have one). Chevy part #3752487. Install with chamfered hole toward you. Drive bushing flush.

This is one of the most rewarding gestures you can do for your favorite old car/truck and yourself, comparing time and money spent to amount of benefit gained.

No more hard starting, hot or cold; no more dim, yellow (dangerous) headlights: no more accessories that aren't compatible.

Instead. you have a new degree of serviceability, safety, and ease of operation. And, it can all be done in a couple of hours, inexpensively, and without any serious modifications to originality' Read on...

First, let's establish that, provided it's in good shape, your original wiring harness is more than up to the task. 6-volt systems carry twice the Amps of 12-volt systems, which means their wiring is considerably heavier than required.

This is the perfect time, too, to convert vehicles with Positive ground (Ford Products, GMCs, MoPars and others) to NEGATIVE ground. Three little moves get that done:

  1. Simply reverse the wires on the Ammeter. (The previous "in" will now be "out" and vice-versa).

  2. Also reverse the wires on the coil. Ignition will be on (+) and (-) will go to coil.

  3. Finish by reversing the battery cables. POS will now go to the starter, and NEG will go to the ground. Much benefit can be gained by moving "ground" from frame to a starter attachment bolt. Do This! (These three operations are done with the battery disconnected!)

Now, to the conversion itself and the (2) basic approaches:
(1) with a 12V generator, or
(2) with a 12V alternator, with internal regulator.
We'll begin with the 12V generator approach.

Conversion with 12V generator
This is an easy way that retains the originality you may be concerned with. Simply obtain a corresponding 12V generator (making minor bracket or mount change), or have the existing 6V generator converted by installing 12V field coils into the existing generator case.
How could it be easier?

(Along with original appearance, there is another distinct benefit to this approach, and that is, that a generator will charge a dead battery; an alternator will not! In fact, operating an alternator in a completely discharged system can damage the alternator, since it requires an electrical source to energize. It is true, of course, that any generator system will show "discharge" at idle, while an alternator does not. With the quick recovery of the generator system at "r's", however, only the most severe loads would overtax it. But, it's your decision!)

Conversion with an alternator
This is probably the more widely used approach but some originality in appearance must be sacrificed.
The minimal wiring changes are no big deal.

Use a DA plug which allows discarding the old voltage regulator. Here, the "Batt" wire that went to the regulator is extended to the post of the alternator where it meets the red wire of the DA plug. Then, "heat" is picked up at some convenient "ignit" spot (the switch or the coil wire) and a wire run to the white DA wire. Presto! The old regulator and the "field" and "arm" wire of the harness are also eliminated.
Very tidy.

Here are the items and changes that will he needed, according to which procedure is adopted:

  1. A 12-Volt battery. (Pick a size that fits the carrier.)

  2. A 12-Volt regulator. (if using a generator)

  3. A 12-Volt Coil.

  4. A fistful of corresponding 12V bulbs (dash, stop/tail, etc.), including headlights.

  5. An ignition ballast resistor which will he installed in the wire from the ignition switch to the coil (You've seen 'em on the firewall. like a'55 Chevy.) Ballast resistor not needed with a built-in resistor coil. A reducer for each accessory, such as your heater.

  6. Use Runtz guage resistor for gas guage and heater resistor ... any fuel, temperature and oil pressure other than mechanical.

Note: Certain components will need to he converted to 12 volts.
Among them: convertible top motors, overdrive solenoids, and radios.
A simple resistor will not work on these.

If your vehicle is equipped with an ammeter,
it will function properly on either 6 or 12 volts,
so it will not need any modification or resistor.