The Stovebolt Site Forums The Shop Area Engine Shop Rocker Arms - 216 Engine

I recently purchased a 1953 Chevy 3100 that hasn't been driven in 18 years, but appears to be mostly original parts. I have never worked on cars / trucks before, but I am committed to doing it right and restoring the vehicle as close to original configuration as possible. I intend to strip it to the frame and rebuild the truck, but want to get the engine running before I strip it down for painting / body repairs.
I have spent many hours digging into this site and have found a lot of useful information.

Saturday, after many weeks of prep work I finally attempted to start the truck and while the engine never caught and ran after the third time I tried to turn it over I heard a noise and discovered two rocker arms had snapped. After that I did attempt to get some oil in and tapped the cylinders to see if they would move at all. That being said I am going to pull the head off this week, but had two questions.
Other than gummed up cylinders is there anything I should be looking for with regards to issues? The fuel system was essentially completely gummed up at the fuel pump and the peacock coming out of the tank (probably from the rust and corrosion inside the tank).

Second does anybody have a source for replacement rocker arms.

I attached two pictures (one of the overall truck the night I got it delivered) and second one I had already loosened the rocker assembly and you can see the busted two rocker arms...(#6 and #7 from the front)

PS I will probably be on this site looking for help a lot.

Thanks
William

Common problem with gummed or rusted valves. Best way to deal with that is to oil the valve stems, then tap them to make sure they move easily, a rubber hammer or 2 x 4 works well. The result as you found out is bent pushrods or broken rocker arms. Never burn antique fuel, which will gum up the valves and also cause that problem.

Ed

Post in the Swap Meet forum for replacement rocker arms. I'm sure someone can fix you up.
You should also check your pushrods. They might be bent.

William Mangum I wouldn't disturb the head just yet,if it will roll thru without much trouble. Sticky valve guides are very common on these engines. Soak your cyliders with marvel mystery oil,same on valve guides,change out damaged parts. Be sure it will roll thru without clashing and try again. Had one in 82 that bent a pushrod days later after I drove it,fixed that it's still running today,strong too was 216. They're tougher than you think. I'd give it a pint of marvel in the gas tank too.

Thanks for the advice. I did soak the cylinders with penetrating oil and couldn't get the two stuck cylinders to move. I haven't tried Marvel Mystery Oil but I will order a bottle.

Is there a particular test for making sure the pushrods are straight? Can I just put them up against a level and roll them and look for any imperfections? Is there a tolerance or bent is bent and I should replace?

No old fuel was run through the system... I purged all of the lines I just didn't break open the carburetor or fuel pump. After I discovered state of fuel pump I did feed directly into the filter ahead of the carburetor. I believe the issue is probably it being gunked up from being parked for 18 years. One question on the fuel is should I go hunt down ethanol free fuel. I have heard several different opinions on this.


I will post on Swap Meet forum for the arms.

Thanks

Didn’t see a swap meet post from you but I think I can help. PM me.

Roll them on a piece of plate glass. They aren't rare enough that you shouldn't just replace bent ones.

William,

Given that you have identified your engine as a 216, a peek at this linked page ARM, valve rocker extracted from the 1929-57 Chevy Master Parts and Accessory Catalog shows there are 2 different "intake" valve rocker arms for your application. Intake rocker L (left) is shown as GM# 839463 and Intake rocker R (right) is shown as GM# 839464.

Your identified broken rockers are both intake valve, but each is of a different orientation (L and R) so you will need one of each.

Just a word of caution before you dive into purchasing/acquiring parts. Suggest you confirm for sure that the engine you have is in fact a 1953 216. Many in the community will vouch for the fact that more often than not, the engines in our trucks are not the originals. A 216 can very much look like a 235 for 1953. The only way to be sure is to confirm what you have by verifying the casting number on the block (and head) plus the stamped Engine ID number on the machined pad between the distributor and starter.

BTW - The site chevy.oldcarmanualproject.com is free and provides access to a great list of old truck publications for everyone to use when working on our trucks!

Let us know if there is more we can do to help.

Don't install any repair parts until you fix the underlying problem(s) that caused the rockers to break in the first place- - - -probably sticky valve guides. The only way to be certain the problem is solved is by removing the cylinder head and doing a valve regrind. People will suggest all sorts of shade tree fixes, but they won't be there with an open billfold when the valves stick again and do more damage.
Jerry

Dan,
Thanks for the advice. I did check the engine number (GM 3835517 15) matches top and bottom of engine. The interesting thing about the two different rocker arms is they are stamped with 82. other ones have different stamps so it appears they were same rocker arm...perhaps a mistake by a past repair?

Jerry,
I would rather spend days/weeks tearing things apart and fixing it right than fix it multiple times so I am certainly going to dig in to cause before I start testing with new parts installed.

William Mangum You can roll your pushrods on the small diameter on glass or any flat surface to tell if they are straight. Once bent you can straighten them bot there never as strong again. If you have 2 cylinders stuck not seeing how you bent pushrods ?? Marvel mystery oil is a Walmart buy about 5$ a quart every day. I saw your truck picture looks good I have saved them that looked a LOT rougher than that. Other things can lock your engine,sometimes just one bolt too long,or rodent nest,driveline,mud dobber nest,starter engaged. Another thing I run my chain saws on airplane fuel and 32 to 1 mix to prime with is some added lube for sticky engines no ethanol. Good Luck you'll get it lit off.

A complete set of rocker arms consists of 4 sets of 3 rockers each, totaling 12.
There are 3 left-handed and 3 right-handed intake rocker arms, which are skewed about 8° from in-line.
There are 3 left-handed and 3 right-handed exhaust rocker arms, which are skewed about 1° from in-line.

William,
Welcome to our site, BTW!

In addition to the excellent advice above, may I also suggest some reading material for you?

Starting a long-dormant engine Tech Tip

Good luck with your project! Welcome home -- You're among family now!

HMMMMMM- - - - -too bad the roller rocker arm system I'm building for a 216 cylinder head isn't a little closer to needing a test drive- - - - - - - -it uses the same rockers for all 12 positions.

Jerry

So follow up to the broken rocker arms. My daughter and I pulled the head this weekend and with the help of a rubber mallet, some creeping oil and a valve spring tool we were able to get them out and start cleaning them. You can see the chief mechanic on it in the pictures.

Interestingly enough the push rods for 6 and 7 look like they were replaced and those were the arms that snapped. I am wondering if the previous owner had a problem in the past and did a bandaid fix instead of doing it right.

Speaking of doing it right I am having consternation about whether to go ahead and pull the full engine and rebuild it since I already have the head off. Having never worked on an engine before I have some anxiety about getting in over my head. Any thoughts on how difficult a rebuild would be?

Thanks William

A 216 is not a good project for an "Engine rebuilding 101" learning curve. Most of the old geezers who are experienced on the quirks of those engines are like me- - - -late 70's or older. Even the average "engine machinist" these days runs away screaming when somebody utters the words "cast iron pistons" or "Babbit connecting rods". Most guys believe a 216 is nothing but a boat anchor, but they're just too ignorant, or lazy to appreciate the finer points of keeping one in good running shape. I'm in the process of developing a series of modern upgrades to the spray-oiler 216 and early 235 engines to keep them out of the scrap yards, but most people think I'm a crazy old coot for making the attempt!

Good helper you've got there! My daughter learned to rebuild engines at the ripe old age of 16, when she let her first car run out of oil and burned up a connecting rod bearing. She's in her mid-50's now, and still doing a lot of her own car repairs!
Jerry

Jerry! I had a German girlfriend in college. She let her VW Beetle run out of oil and her dad made her rebuild the engine in the basement of their house. She checked the oil every time she fueled up after that.

An air cooled VW engine is another one of those "mechanic's nightmares" to rebuild. I drove a 63 beetle 1200 CC with a "big Bore" cylinder kit from J.C. Whitney back in the dark ages. It finally wore out the piston rings, and Whitney wanted to sell me a complete new kit- - - -cylinders, pistons, and all. I ended up rebuilding it with 85 HP flathead Ford rings and replaced the worn out piston pins with ones for a Corvair because stock wrist pins were too short for the oversize pistons.
Jerry

I never was able to give my wife Y gene in order to give us a daughter (two fine boys though), but if I did, I guarantee i would have raised her to be just like your helper!