The Stovebolt Site Forums The Shop Area Engine Shop Engine knock :-( A winter project ahead

Well, the other day when I took my truck to a parade and car show, It sure sounds like I burnt out a rod bearing. It has a loud knock. Jerry says I likely had a misaligned spray nozzle that prevented oil from reaching the dipper on the rod cap. I didn't mess with the nozzles, but the previous owner had the pan off and may have tweaked one or more. Looking for a shop that can deal with the likely scored crankshaft. I'll know more when I pull the engine and tear it down.
But the truck still looks pretty.

Sound like a great chance to join the 261 club!

That's an option. I'm on the lookout for a different engine, depending on how bad the 216 is. I'd like to stay with an year correct engine, but upgrading isn't out of the question.

Especially since the whole truck was already apart. Now you have to be super careful getting the engine out.

I may be in a similar boat if I can't get a handle on Ol' Roy's overheating issue. What sucks more though, is not being able to drive the truck.

I do need something to do over the long cold winter. My wife doesn't really need her garage back yet.

Kevin, I am so sorry to hear this. Your truck is looking wonderful and now this. Argh. You have a good attitude about it so keep smiling, this too shall pass.

If you can find a machinist who isn't afraid to do a little creative whittling, it's possible to adapt a 235 rotating assembly to a 216. That eliminates the Babbit rods and the spray oiling system, and uses a higher volume oil pump designed for a 54/55 235 with the straight oil pan rail on the passenger's side. (Melling M-29) With a LOT of modification, that "216" can become a 258 that looks completely original from the outside.
Jerry

Kevin, I'm sure your familiar the Superior Machine and Welding. They did a lot of work for me when I was at Elmendorf AFB in the 90's. Good folks to work with.

That is terrible news. I can't imagine the hugh disappointment of such a failure shortly after getting such a long project on the road.

Wow! That just plain sucks! Maybe it’s not as bad as you fear! Let’s keep our fingers crossed! Still sucks though and I wish you some good luck!

Thanks Phil. It's bad enough that the head will have to come off. I'm almost certain that a rod will have to be replaced at a minimum. The crank may have survived, but really not likely as the knock is pretty severe. There's a squeak as it turns over as well.
I plan on consulting with Jerry about his suggestion of upgrading to a 235 rotating assembly if the crank needs work. 235 Crank, rods and aluminum pistons would make sense as an upgrade as it has to come apart in any case.

You can always put your existing valve cover on a later 235 of better yet a 261. Only us experts will know the difference!

Hope it’s not that bad but a 235/ or 261 sounds good also .start looking in the weeds when travelling the roads up there.

Mr Hansen,
Allow me to help you rationalize your way into a 235 —-
Imagine this is 1955. You bought your truck new in ’51 , and now- after just 4 years of service the darned engine is knocking. You go to see your trusted friend who runs the local Chevrolet dealership, a guy you knew since you were kids. “Dang it Dan” , he says, “that’s a shame!
Listen - instead of tearing down that 216 , what do you say we just replace it with the newer 235? It’ll have more pep , and it’s got better bearings! I’ll give you a great price since you’re a life long customer.” “Well” , you say , “ that sure makes sense to me , when you put it like that.”

Dial the clock ahead to 2024. Someone lifts the hood on that ‘51 and sees a 235 that looks like it’s been in that bay for 70 years …. The person under the hood says “Looks like someone made a good call way back when.”

The end.

Or you slap a 216 valve cover on that 235 and everyone says, "Wow, look at that original engine!!"

Not that *I* would know anyone who did that ....

Falsifying engines on an AD Truck is a crime in Rural Missouri.....just sayin.

On some of the cylinders in 216 engines you can pull the rod without pulling the head. I don't know witch cylinders they are but I did it on #1 years ago.
It probably won't help though as the crank will probably be damaged too.

George

In rural Missouri it's highly likely you will ever get caught.

George

Thought of doing that on my 235 but the 4-bolt cover hasn't leaked a drop after 750 miles on the rebuild, so now I'm hooked. And it looks pretty good.

For 40 years I wanted original everything. Now I wouldn't trade the 235 for anything (well, maybe a 261). It's just so much more usable, and as much as I love and respect the 216, the 235 is just plain better and should've made the swap years ago, as my truck was never a suitable candidate for "original" restoration anyway.

Kevin here's another vote for 235, or perhaps a Hotrodlincoln-ized 216.

Put a 235 crankshaft and rods and a set of .060" oversize Buick 215 V8 pistons in the 216. You'll have a 235 with "numbers-correct" casting numbers for the original engine. A 3/8" stroker crankshaft will make it a 258.
Jerry

Jerry, I've been studying that a bit and it seems that a 235 crank has to have the #3 main journal widened just a touch for the thrust bearing in the 216. So .060 OS Buick 215 pistons would be the same size as standard 216 pistons? And have the proper deck height with the 235 rods? If I get to that point, I'll give you a phone call to discuss.

258 Stroker …?

Nah , everybody has one of those, try something different.

You can either widen the thrust face on the 235 crankshaft, or narrow the #3 casting web and main cap in the block to accept a 235 main bearing. If you whittle on the block, you can also use the 56-63 235 main bearing shells that are much more available (and less expensive). I'm building a machining fixture to do that, using my Van Norman cylinder boring bar as a driver. 215 Buick standard bore pistons are the same size as 216 pistons. 60 over gives you 235 "standard" bore and stroke- - - - -in a 216 block.
Jerry

The ubiquitous Ford 4.6L V8 has another piston worth exploring. Standard size is 3.55….so it could possibly serve in a large overbore 216. And the 4.6 pistons in oversize form, would span the 235’s bore size.

Looks to me like it has a lower compression height than the Buick/Rover piston Jerry mentions. I haven’t done the math on what length of rod would be needed.

Poor Kevin. His post (thread) may get move again and end up in HiPo (sometimes referred to as "crazy stuff") area.

JW, the Buick piston has a short dish in the crown, so even if the compression height isn't exact, it can be adjusted a little without compromising the integrity of the piston crown. It also has the same size wrist pin as a 235. The 235 crankshaft and connecting rod plus the Buick piston works out almost exactly in relation to the shorter 216 block. A 235 block is 1/8 inch taller than a 216 to compensate for the longer 235 stroke, while using the same rod length and compression height of the piston. 235 standard bore aluminum pistons are a drop-in fit to a 216 bored 60 over, giving a displacement of 224 cubic inches with the 216 stroke.
Jerry

I res(ent)/(emble) that remark.

I think we’ll have to wait until Kevin disassembles his engine and makes a decision as to which direction he wants to go.

Hotrod Lincoln: My my crude math, it’d take roughly a 7.5 inch connecting rod to make the 4.6 Ford piston reach the deck of a 235. I’m not super familiar with any rods that long. Looks like may some diesel rods are in that range.

And I also wonder if you might end up with interference issues with rod at the bottom of cylinder.

(Last “crazy stuff” comment from me in this thread)

I'm using NASCAR style rod bolts with 12 point heads to give a little more camshaft clearance on the stroker crankshafts with a 4 5/16" stroke. 3/8-24 helicoil inserts in the rods give approximately 2X the thread engagement of a regular stovebolt rod bolt and nut.
Jerry

Update on my issue.

I picked up a parts 216 (badly cracked block) and 235 engine on Friday. Got the 216 disassembled over the weekend. So I have a couple options - using the 216 rods (one is iffy) and crankshaft in my engine, or the crank and rods out of the 235 along with Jerry's suggestion of Buick pistons. That's assuming the parts are in decent shape - drained some water out of the pan, so it may be unusable. It's currently locked up, but I have the cylinders soaking to see if I can get it turning.

Today, I got the front clip off the truck and pulled the engine today in preparation for disassembling it to see what the damage is. Pulling the front clip intact avoided all the alignment issues with unbolting the radiator support. It balances nicely with the spreader bar attached at the fender support brackets with the radiator still in place. Everything came out pretty easily. Only forgot to disconnect the clutch pedal linkage.

Will be interesting to see what happened.

I'm not expecting that it'll be that easy. It sounded bad enough that the crank is probably scored and needing reground. Tracking down a place to do any engine machine work is getting harder up here. But the crank out of the free 216 I got looks to be in good shape. Of course with babbit rod bearings, the piston and rod have to come all the way out to be replaced. Definitely not as easy as insert bearings.

Back when I bought one of my crankshaft grinders from King's crankshafts in North Carolina, I asked him if he would be interested in drilling 216 cranks for pressure lubed rods. He said the first one would be $$$$ since his CNC milling machine would have to be programmed, but others would cost a lot less. Unfortunately, it looks like he's out of business now. His father made custom NASCAR billet cranks for many years.
Jerry

Well, the verdict is in.

Got the engine on the stand and flipped over to remove the oil pan. It was pretty easy to find the rod that was loose. Rod #1 has the babbit completely gone and the crank is scored. It's a shame as measurements revealed that this crank was standard size, with the scored #1 crank pin just a few thousandths under standard size.

I'll be holding on fixing it till I get the 235 freed up and see if using the crank and rods from it will be an option. If I go with the 216 crank and rods (will need one replacement rod), I'll likely put in aluminum pistons. I'll need to measure the bore size before jumping in to that.

Rats! I forgot about the poured bearings.

Do you think the spray oilers were not aligned properly?

If you plan to go back with Babbit rods, PM me. I have a big stash of reconditioned ones- - - -a few standard, and several undersizes that I can hone out to STD dimensions (or a few thousandths under). Something like a .005 under would be possible, and scrape-fit it to a crankpin that's been polished round and smooth. A little creative tinkering is possible with Babbit- - - -something that would be impossible on a precision insert bearing. Aluminum 235 STD diameter pistons are a drop-in fit on a 216, with a 60 overbore- - - -gives you 224 cubic inches (and a bit more compression). Replacing the cast iron 216 pistons with aluminum also reduces the centrifugal load on the rods and lets the engine accelerate better. It was a very common modification to a 216 50+ years ago.
Jerry

Thanks Jerry. Until I find out if the 235 can turn after soaking, I don't know if I'll need any replacement babbit rods. But I'll give you a shout if I do. I'm going to try and put this back together with a minimum of machine work (crank polishing or grinding or cylinder boring.)

Good luck- - - - -"Buy once, cry once!"