Seller states it has a 366, but I have 2 350s sitting in my shop with the same oil pan and heads. I cannot get to the number on the block, so how can I tell a 366 from a 350? Other noted items on the motor, Rochester 2 barrel, with electric choke (cab has manual choke knob), oil pan only holds 5 quarts (I remember the 366 holding 8).
A 366 Chevy is a Big Block, not a small block. The valve covers are about twice as wide as those on a 350. A 427 would look almost identical to a 366. That's the only two big blocks that came in a C65 that I can remember.
I dont remember ever seeing a 366/427 with a 2 barrel. If it has 4 bolts holding the valve covers on its a smallblock probaly a 350 but it could be a 327 305 307 283 265 or a 400. If its a smallblock from a truck it will hold more than 5quarts.
As the others stated, 366 is a big block, really quick id, valve covers are wider, and have 8 bolts holding them. Could be a big block and not be a truck block though, truck blocks and passenger differed in the fact that truck pistons had 4 rings instead of 3, this made it necessary for the deck height to be taller. You can see this without a teradown by looking at the space between the water pump and block deck. A truck will have a space there between the water pump and head that is almost an inch. The passenger deck will have almost no space at all. There was a period in the late 70's when there was a possibility that a truck could have had a 454 truck engine. They are rare though because they were only produced for 18 months. I found one of them the hard way, by trying to replace just one piston, the bores are the same between the 427 and 454, but the strokes are different. That also brings up an issue between the 366 and 427, you cant take a 366 and bore it to a 427, there is not enough metal in the cylinders. >366 The 366 Big Block V-8 (6.0 L) gasoline engine was used only in Chevrolet medium duty trucks and in school buses. It had a bore of 3.935" and a stroke of 3.760". This engine was made from the 1960s until the mid-1990s. The 366 used 4 rings on the pistons, as it was designed from the very beginning as a truck engine. The 366 was only produced as a tall deck engine with a 0.400" deck, taller than the 396, 402, and 454 short-deck Big Blocks.<
Thanks all, it is definitively a 350 based on info provided. I bought it for 900 just to use on my property moving dirt, next question, how do you tell what transmission is in it, I would like to find one to replace the one in it, it will not go into 2nd or 3rd (which is not much of a problem for what I want to use it for). I have not looked to see if it is something simple yet.
what year model is it? If its a 4 speed cast iron case, cast iron top, its most likely a Muncie SM 465, fairly dependable tranny's but prone to shifter and synchronizer issues. Most common reason for the symptom that you are describing is a bad input bearing and intermediate roller gearings along with a probably bent shift fork. A bit of a heads up, if you pull it out and go through it, the shifter has to be halfway in reverse in order for the reverse shift fork to clear the main cluster. and you will need a split half bearing puller to remove the bearings. And the parts won't be cheap......... The input bearing that is used in it has only been built for that one particular application... NDH is the ONLY manufacturer of it!
It feels like a syncho issue, if you try to shift it grinds, it is a 1984 C6500.
If it has the 465, a replacement won't be an issue. Those transmissions are a dime a dozen it seems, very common. Used in everything from a C10 to a C65.
One other difference that I am certain of, relating to the big block truck 366 and 427 engines, is that they have a much larger bellhousing and a larger flywheel and clutch assembly. The larger bellhousing would mount on any Chev V8, but the larger ring gear would necessitate using a matching starter. The way they might have got around this, would be to have used the big block starter on the small block engine. The starters will interchange, and the big block starter has about 30% more torque. I have a 366 engine, and I also have a 427. Both have the higher deck height, and both have the 4 ring pistions. GM did make a 2 barrel truck manifold, I saw one on a 79 C65, but both my manifolds are 4 barrel and were equipped with a Holley carb with a governor. Bob
If you go looking for an SM465, just make sure you don't end up with an earlier SM420. Nothing wrong with the 420 (it has an even lower 1st), but the 465 is a couple inches longer and uses a different bellhousing.
I will eventually get another SM465 but several companies online have them for 500-700 rebuilt, most used around here are going for 350 with no assurance they work and they are ones from 4x4s with the wrong output shaft. If I have to break open a case I might as well buy a rebuilt kit and rebuilt the one in it. I have the C6500 repair manual for that year and it has the SM465 section in it. Might give it a go this winter if I do not buy one.