The Stovebolt Site Forums The Shop Area Engine Shop does a 1955 2nd series 3100 6 cyl have vented valve covers

hi.

I have a 1955 2nd series 3100. don't really know its history other than it has been worked over a couple of times - paint and interior for sure.

6 cyl
1 barrel carb
oil air filter housing.

I have done a lot of searching, but cannot determine absolutely, can a 1955 2nd series 6 cyl have a vented vale cover. I 'think' it might be the original engine, but cannot say for sure.

can anyone say for sure and list a documented source?

thanks in advance.

There's no such thing as an "absolute" with these trucks. The best documented source will come from your interpretation of everything you read and are told, so it's a bit unlikely you'll ever be "absolutely" sure. ESPECIALLY for a 1955 with a mid-year body style change AND the V8 option coming into play. Lots of mixing & matching and use of legacy (54-55.1) parts.

I know what you're asking, and I think you could eliminate a whole lot of guessing if you'd post the engine serial number and the head casting number. We could for sure determine the range of time the engine was built (I think even the month?). Whether or not it was built & immediately installed in your truck is a whole other story.

The three 100% original 1955 3100 2nd series trucks I've grown up with (I only own one) all did NOT have vented valve covers.
Undocumented source, of course.

Brad

Edit- Retract some of the above, because there are some peculiar configurations & years that did have vented valve covers; Tim - tclederman has a lot of this info on his website.

Define vented? slits in the sheet metal or a twist on breather?

Ah, good call thoroco- For me, I'm calling "vented" the sheet metal slits (that my valve cover does not have).

The oil filler cap at the front (fan end) of the valve cover is twist on and vented. It is not flat.

Brad

As Brad suggested, find and post here the casting codes and date casting codes and engine serial number.

The 1955-2nd valve cover would have no slits in it; however, there were 3 styles of 54-62 valve covers and they can be used on any of those years'engines.

Tim, could you list or describe the 3 styles of 54-62 valve
covers that Chevrolet used?? Are you including the two
Corvette covers in those three?

dg

"could you list or describe the 3 styles of 54-62 valve covers that Chevrolet used?? Are you including the two Corvette covers in those three?"

" . . can a 1955 2nd series 6 cyl have a vented vale cover . . "

Nope, no need to mention Corvette 235 covers in trying to distinguish different 4-bolt covers - I was referring to high-pressure truck engine covers - the ones with four side bolts/screws. In my table, I refer to them as "Third Generation Stovebolt engines" (other people might distinguish the generations differently).

I assume that 53-55 235 Corvette engines all had the same older-style of two top-bolt valve covers, with vent slits and non-vented oil filler-cap.

Valve Covers (with 4 side screws/bolts):

1. 54 cars & 54/55st trucks - 4 vent slits in the top, non-vented oil filler-cap in front

2. 55-58 cars & 55nd-1963 trucks - no vent slits in the top, vented oil filler-cap in the front

3. 59-63 cars - no vents in the top and vented oil-filler cap in the middle

I am most likely wrong on cars/trucks being different in 59-63. However, both of my 1960 and 1959 261s both had valve covers with filler in the front. But, they might be "outliers" because they were most likely "special order" engines. They were big truck engines that should have the standard-equipment PCV, but both engines came with no PCV set-up (school bus engine and high-school shop-class engine).

Please correct/clarify any of the above. I will revise the information as necessary

Here is a photo of Stovebolt valve covers (2 bolt and 4 screw/bolts) from a lecture on Stovebolt engine characteristics given to the Puget Sound VCCA chapter by Pre '68 Dave (a while ago).

Thanks, Tim!!!

Brad

I do not advocate ruining vintage valve covers, but I would think there is a tasteful way to seal those vents that are open to road grime and underhood crud and then put a filtered breather cap on. If you did it on the inside, you could do it in such a way that nobody would be able to tell.

You would see engine longevity improve for sure. The same engines only filtered about 18% of the oil. No wonder they were susceptible to top end oil sludge/blockage.

thanks to all for the replies.

slits in the sheet metal

I found some numbers after cleaning them up with degreaser


on the carb side of the engine I found in big numbers
3836848

on the dist side of the engine I found in small numbers
848
850

(where the 848 is directly 'above' the 850)


I tried to see the code by the distributor but have to figure out how to get my head down there to see. lol
[/b]

I squeezed in there and see this on the plate next to the distributor:

FI2IHE

not sure if the 'I's are really '1's.

cleaned off years of grease and gunk and see this right above the starter

AI57

not sure if the 'I' is really a '1'.

please review my findings and let me know what you think. it is quite involved, and a little bit confusing, as there are different formats for different years. thanks.




the a157 on one web site breaks down to
block date-casting code

A = January
15 = 15th day of the month
7 = 1957


the FI2IHE on one web site (gm heritge site for 1957 trucks - all of the other years had a different format) breaks down to
engine serial number

F = Flint
1 = January
21 = 21st day of the month
HE = 4000 regular production for 3100s, etc.


so, if correct, the engine was cast on January 15, 1957
and the engine serial number applied on January 21, 1957.


if I am right, I have a 1957 engine in a 1955 2nd series 3100, and someone put in a pre-1955 valve 'vented' valve cover (maybe to make it look cool????)

Man, this all sounds pretty typical...
Nice (outstanding) job looking up your engine numbers. I can't double check them at my location, but seems like you've got it.

Also, the ' 848 ' number is the cylinder head, and that's the casting number you want.

Brad

My books tell me that "HE" is the designation for a "Thriftmaster 235 with H.D. Clutch" and was installed in 1957 Model year 3000 and 4000 Series Trucks.

Are you sure your truck is a 1955-2? Whats the number on the door post? Does it match the frame number?

Mike B

Right.........

Didn't you get all this figured out in December???

Brad

lol!

I posted now because I never really got a definitive answer about the vented cover (at least, to me).

like:
was it a first series engine that they put into a second series?
or
was it a first series engine that someone swapped in.
or
did they still put the vented first series covers on second series engines in 1955
or
was the top part of the engine mated to a different bottom at some point?
or
etc.

right after that first post, winter hit here in the northeast and I did not work on the truck until recently.

I vaguely remembered posting about the vented cover and not getting a definitive answer, so I posted again.

I did forget finding that engine serial number (getting old...), and the breakdown someone provided (which did not make much sense to me at the time, and actually left me more confused than before - like: how could it be a 1957 engine with a vented cover that looked original, but vented covers were only used up to 1954, but it was in a 1955 and looked like it had always been in there?).

I have to say that going through the whole exercise again, and checking out the numbers on the engine (and sources of information like the gm heritage site which I did not know of until I fell over it), was a good experience for me (and might help someone else in the future?).

thanks to all for the replies and advice.

the vin plate on the body door post shows it being a 55. where on the frame do I look to find the year?

so much to learn....

Good decoding, hplacesbf

Casting codes (casting dates, in particular) are definitive. However, valve covers can be moved around from any 1954-63 engine/year.

Here are locations of block and head casting dates.

hplacesbf- yeah, I was wondering if you'd ever posted a link to a picture of your truck, & read a few of your posts. And then I saw all those engine numbers...

I was hoping to keep you from looking for numbers you'd already put on here.

Brad

It should be stamped on the frame next to the steering box. It might also have a second stamping of the number under the cab. Mine is that way, and I have heard reports of others that are the same.

Tim, I have seen a few '59 trucks, plus 1 '60 with the 3rd style cover with the filler cap in the middle. All were spotted in local salvage yards, but as far as I know, they were still original to their respective trucks Nothing seemed special about the engines, no unusual equipment other than one had a governor on it. The '59s were a 3800 flatbed and a 4500 School Bus, the 60 was a C60 with a 261 (yes, I regret not grabbing that engine).

Bill,

You are right about the vented oil-filler cap in the middle the truck 235 and probably the 261.

My table/chart is also wrong about the year:
1958 truck - center of the valve rocker cover (it is not shown for car, but most likely the car 235 was the same?)