The Stovebolt Site Forums The Shop Area Engine Shop Rebuilding Engine

Hi everyone. I was thinking of rebuilding my engine, but I was wondering if my 1948 216 would be the same to rebuild as most engines from other years/makes? I may have heard something about these engines being different, but I can't remember. Thanks.

The basic rebuilding steps are the same, until you get to the connecting rod bearings. 216 rods have the bearing material bonded to the rods, so if they're worn beyond adjusting with shims, the rods have to be replaced instead of just fitting new bearings. Checking the cylinders for wear, reboring cylinders, fitting pistons, rings and main bearings, and reworking the valve system is done just like any other engine.

The oil pipes that supply lubrication to the connecting rods on a 216 or early 235 need to be aimed properly to prevent oil starvation at speeds above idle. Adjusting the oil clearance on the connecting rods by using the proper thickness of shims between the rod and the cap can be a little tedious, but I recently talked a fellow stovebolter through the procedure by PM, email, and telephone, so it's not an impossible job.
Jerry

Won't hurt to mention the option of having the machine shop bore
the rods for a set of insert bearings.
dg

The main bearings and camshaft bearings can't be done in a single pass, but because the journals are all different sizes must be re-sized individually, much more labor intensive.

Who else is talking about resizing main and cam bearings? Those are precision-fit replaceable items. If the main saddles need line-boring that's way beyond a normal overhaul. I have line-bored several 216/235 engines with a single pass- - -just set up a different cutter for each bore and cut them all at once. Any machinist worthy of the name can do that.
Jerry

I missed the part where he said "rebuilding the engine, except for the bearings".

He's not rebuilding an air cooled 2 cylinder.

Easy there now boys. Your gonna scare the newbie away. Give him a chance to breathe and ask a follow up question.
Carl

Bryce S,

When I was a boy, I rebuilt a 216 by simply following the Shop Manual.
I had never even seen the insides of any engine.

All I had was a Shop Manual on microfilm and a new $99 Craftsman toolbox and torque wrench and tune-up tools.

A few good old boys gave me advice.

You have us for advice.

I'd only rebuild a 216 now if I wanted to stay original. I'd now look for a good 1956 or later 235 for a rebuild. The water pump would need an adapter for the engine to fit properly in your truck.

Whichever way you go, read the Shop Manual for your truck and ask questions.

Good luck,

Now don't cha go knockin' those reliable old 216's Tim. Mine
gave a little town in Gray, IA close to 55 years dependable
service first as their one and only fire truck then as their
run about till I got it in '05. And now over the past decade
I've added another 16,000 miles to the odometer with nary a problem.
Drive it all the time at 55-60 mph highway speeds.
Yep, good, dependable little workhorse that 216.
Come on and take a ride around the block with me.

dg

Thanks for all of the help guys. Yes, I'm planning to go original unless the engine's condition is so bad that it would be better to replace it, but so far it's looking alright.

Yes, you are right, Denny - smack me

The actual rebuilding of the your engine is no different from any other engine.
The question is, is it worth it, to rebuild a Babbitt Pounder 216 straight six.
If you talk to Patrick at Patrick's Antique Cars & Trucks. He says walk away.
Mainly because they don't have full pressure oiling.
Just these little dippers scoop up the oil, which lubricates the connecting rods.
Watch this Slow motion dipper video. Go to 7:19 into video.

If your going to spend the money.
Spend it on a full pressure oiling engine.
The connecting rods have full pressure oiling, through oil passage drilled into the crankshaft.

He must not have read my reply huh Tim!

dg

Yes, Denny, to each his/her own motivation.
Maintaining originality it one very good/valid motivation.

For the sake of having correct information here, Jorb, your description of a low-pressure 216/235 engine's lubrication of the rods is not entirely correct.

At low RPM you are correct: the rod dippers scoop up oil to lubricate the rod bearings (by the way, this is not splash oil lubrication - thanks for not using that term).

However, at higher RPM, a stream of oil is "shot"/directed into the dippers (a open "pressure-lubrication" system).

it isn't real hard to make a full pressure 216.

I think someone should clarify what is the definition of a full pressure oiling engine.
Another words,
What and how is a 216 engine lubricated?
What and how is a 235 full pressure oil engine lubricated?

What needs to be done to make a full pressure 216?

I use the term high-pressure and low-pressure.

GM sometimes used the term full-pressure for both systems (or parts therein).
Here is a description of the high-pressure full-pressure system that compares the new system to the previous system.

The 48-51 Shop Manual and the 1954 Shop Manual describe the low-pressure and the high-pressure engine-lubrication systems (respectively).

The major difference is how the the rod bearings are lubricated.

If you are by any chance interested is see what a real splash oil system is, look at the older (much older) Shop Manuals on the Old Online Manual Project.

On the full pressure engine.
There must be a oil passage drilled inside the piston connecting rod.
To lube the piston wrist pin.

Thanks for the info.
Pretty much clears up the difference between the two or three (splash) engine lubrication systems.

Here is a picture of the piston pin boss oil passage. Check hole in oil ring groove.
Pin oilers use the scraping action of the ring to force oil into the piston pin boss to lubricate the pin.
Production engines relied on splash oiling but performance engines need a little more help.
Source bottom of page

Thanks everyone. I finally got around to checking the condition of the bottom of the engine. Do these parts tend to stay well preserved or were parts possibly replaced? Also, are the shaved marks from the crank being balanced or something rubbing?
http://s300.photobucket.com/user/Bryce_Sheedy/library/Engine

I would guess the shaved part is for balancing the crank and nothing to worry about, but guesswork isn't good enough. Check every place that crank can contact other metal everywhere with a flashlight and make sure. The engine looks clean inside.

I like to check the torque spec then tighten everything in site to that spec before buttoning it up. Just in case something got loose which is doubtful. I like to inspect the bottom of the pan to see what sort of crud has accumulated too. If its just dust mixed with oil you are good to go. Anything larger would be suspect.

You can eat off of the bottom end of that engine. Do you know the history of the recent rebuild? I would not be surprised if that engine has ever been run since it was rebuilt. Those shave marks are definitely from balancing.
Carl

So it definitely looks like it was rebuilt? The guy I got it from didn't do much with it or know a lot about it, so I don't have any history on it. The only time I ran it is for about 5-10 minutes over a span of a few days because I found a giant coolant leak in the rear plug. I'm glad I didn't run it much because there was lots of coolant in the oil after I ran it, so hopefully nothing was damaged.

Check the clearance between that crankshaft counterweight and the camshaft lobe it aligns with. That ground area might have been put there to assure there's no contact between the cam and the crankshaft as the counterweight rotates close to the cam. Some crank and cam combinations get VERY close together at certain points. If that's a splash-oiler 235 with the longer stroke, things can get very close!
Jerry

I don't know how the coolant would get in the oil from the rear plug. That mystery probably needs to be solved.

I think there might me another problem as well as the rear plug because there was coolant in one of the cylinders. I'll be sure to check the clearance!

If you have coolant in a cylinder, you probably have a cracked head or a bad head gasket.

I'm hoping it's the head gasket but I'm planning on getting the head pressure tested to see. One thing that makes me believe it's the head gasket is that when I took the head off the gasket came off easily and was wet on one side. Could this indicate a badly sealed head gasket?

How tight did the head bolts seem to be when you removed them? Improperly torqued head will leak at the head gasket, either from torque being too low, or from proper sequence was not followed.
Carl

Hm, if I remember correctly most of them were pretty tight, some more than others. I think a few were a lot easier to remove than the others.

I'd take it to a machine shop to be pressure checked for cracks/leaks and for straightness. If it passes all of that, reinstall the head with a new head gasket, following the factory torque sequence.
Carl

Ok, will do. Another question about the bottom end. Since it looks to be recently rebuilt, should I take it apart and inspect everything or just leave it? This is my first bolt so I don't want to mess anything up.

Given that the previous owner botched the leak at the head, I would check EVERY moving part in that engine.
Carl

Amen

If your going to take it to a machine shop to be pressure checked for cracks/leaks and for straightness. As 52carl suggested.
I would leave it together and see what the machine shop recommends.
Before taking it apart yourself..

I really hate to get into somebody else's "rebuilt" engine, particularly one with problems. You have no idea what has been done correctly, or maybe hasn't been done at all. All of us have our own ideas of what a rebuild job consists of, and few of us can agree on what's acceptable in the way of tolerances and methods. Unless I do the work myself or commission it done to my standards by a competent machine shop that I trust to do things my way, I consider any engine I acquire to be a "rebuildable core" at best.
Jerry

Thanks for the replies. I've been really busy lately, but what would my next step be after getting the head pressure tested? I'm going to get the head tested soon, but I was wondering what I should do next with the engine. Thanks.

This is what I do for every unknown engine in my shop:
1) Take the Head to my very good and reliable Motor Machine Shop and have it gone completely through. Cracks, damage, etc. They will tell you if the Head is good to go. Then you can decide how far you want them to take it.

2) Take the Engine to the same place after tearing it completely down. Nothing is left together. They check the Crank, Piston Rods, Rocker Assembly, everything for serviceability. When done, there is no question about the engines performance. The entire procedure is here: http://devestechnet.com/Home/Project1959235

The problem with doing things half-fast is that you tend to leave questions unanswered. When that happens, how do you feel about pulling the engine again in a few thousand miles or less and start all over? Bryce.. take it slow and don't let your schedule dictate what the engine needs. Just MHO.

That's a great point. I'll make sure to go slow and do it right the first time! Thanks for the help