The Stovebolt Site Forums The Shop Area Engine Shop Project "bad pennie"

This may turn into a long post but I'm at the end of my rope with this project.
Last fall I built a 59 235 for a friend of mines 52 2 door hardtop with a powerglide. He fell in love with the 62 235 I built for my 50 PU and pestered me until I agreed to build him one.
List of new parts included pistons & rings(.030 over), bearings (all standard with a nice polish on the crank), oil pump, cam and lifters, water pump, valve job and head milled .025 (just to make sure it was nice and flat), fenton headers and intake with 2 rochesters. All tolerences checked per motors manual and all fell at or near the center of the specs. Engine was broken in properly with quality breakin oil and driven only about 3 miles then went to the upholstery shop for the winter.
My buddy decided to drive it home from the upholsterer this spring and proceeded to get on the interstate and run in 70 mph for about 45 minutes steady! He overheated it (non working temp gauge, now replaced!) so badly that it melted the bearings, rods, mains and cam bearings out of it and turned the rod big ends black.
Back out and now after tuning the crank, .010 under mains and .020 under on the rods and checking all the rods for round and straight, it went back together.
Ran great for 400 miles, 40psi of oil pressure and never got over 180 degrees.
Life seemed good, until the noise came.
#2 rod bearing was knocking.
Pulled it again to find that #2 was just the first one that was going bad. The mains and cam bearings look great but the rods are all scored to varying degrees, particularly on one side of each throw.
Let me say, I have built well over 100 engines of all makes and models over the last 35 years and this one is the first that has given me this much greif. The machinist I use is 3 generation in the same location and very reputable and my buddy learned his very expensive lesson and I'm sure was not doing anything stupid this go round and I don't believe to blame for the failure.
My question for the stovebolt experts here is "why, what could have happened?"
Could the heat have changed the metalurgy of the crank or rods? The bearings seem to be correct as marked, I have had some in the past that were mis-marked but I checked these and they seem to be correct. Now I'm gunshy and thinking of finding a different crank and rods, or a different engine and start over, or even (gasp) giving him mine!
This thing is like a bad penney!
HELP!

First of all ,don't give him yours. I think I would give those rod big ends some careful measuring with a bore gauge. I know you measured them before, but if the rod bearings are all scored on one side , that is telling you something. Is there any debri floating in the oil galleries in the crank? If the rest of the bearings are good, I wouldn't suspect an oil pressure problem. Are the pistons installed correctly on the rods?. Just trying to offer some idea's to set ya to thinkin' Hope you get to the bottom of it

Believe me thats why I'm asking. I figure the more comments I get, the more possibilities can be examined. I have been second guessing everything I did, including the installation of the pistons on the rods (they were done correctly by the way). I have checked every oil passage all the way down to the squirter holes in the rods, all clear. There is some bearing material floating around in the oil and I'm sure it is the cause of some of the damage to the other bearings.
I'm thick skinned and know I can make mistakes so keep the ideas and ?'s comming.

I experienced a near identical problem in the mid 60's with a 352 Ford that had misteriously wiped all the main bearings from #3 back AND the back 4 rod bearings.
Cleaned it up well and corrected the shaft, rods, and rings for what should have been a good freshening up.
On startup the rods were starting to get noisy within 15 miles--dropped the pan (what a bear to remove) and inspected the bearings to find the same thing.Every thing from center main back was starving for oil.The pump is in the front on the FE engines.
Out with it and teardown for inspection and found the block cracked from the camshaft down to the #3 main right through the oil gallery.Evidently when it warmed up it leaked enough to starve downstream bearings.The oil pressure was never lowered enough to make the light come on.
Drop the pan and find a way to pressure up the oil system--air or oil and look for a sizable leak.

Did you do a complete teardown to the bare block on the rehab after the rods failed the first time? I always make it a practce to open up every oil passageway and scrub them with rifle brushes anytime I've had a bearing failure of any kind. It's surprising how much crud can hide in an oil gallery, and turn loose at the worst possible time. Also, if the rods were discolored, they should have been trashed, or at least totally reconditioned. I file the big end, (rod and cap) .002" under minumum bore size top to bottom, and hone them until they're back round and to the right bore size. Just measuring doesn't necessarily make 'em right.
Jerry

Yup everything was torn down and thoroughly cleaned (pressure tanked and brushed). Rods unfortunatly I think were the problem.
Machine shop checked them for straight and round but I can't help but feel that they were slightly oversize and not caught before the last assembly. Really looks like there was too much clarance right from the start. My bad too as I didn't plastigage them after I got them back from the shop, I just trusted that everything was to spec. Like I said, I have never had reason to not trust the machinist I have used for years in the past so I just didn't think it was necessary. I will in the future though just to know for sure.

It's worth noting that the common spring loaded type of cylinder/brake hone will do absolutely nothing to correct for an out of round condition. Even with the right equipment attempting to correct for out of round, bellmouthed, barrelled, tapered, or other wear/distortion patterns by means of honing requires specific tooling and procedures briefly described here:

http://www.sunnen.com/graphics/assets/documents/bd2da13109ab.pdf

I ran the connecting rod reconditioning room for a big machine shop in Nashville Tennessee for several years. Our rod reconditioning equipment was made by Sunnen, with approximately $50,000.00 worth of tooling for rods up to a big-end diameter of over 4". We specialized in heavy-duty Diesel engine components, and the average diameter tolerance we worked with was .0001" (1/10,000"), measured with a dial bore gauge. Is that accurate enough?
Jerry

The comments in this thread and by several other long time and very trusted and competant machinists who have looked at the aftermath of this in person all lead us to believe that the rods and/or rod bolts are to blame for this most recent failure.
Best guess untill all the measurements have been completed is that either the rods or bolts stretched or deformed enough to create a loose condition which then led to the bearings pounding themselves out. They wouldn't have to go much as only 1 or 2 thousanths would let them begin to fail. Upon close inspection all six were at different stages on their way to failure.
The main bearings are good and the cam bearings look like the just came out of the box.
Next question is do I turn the crank again (would go to .040 under) and get new/reconditioned rods or look for another crank and rods both?

There's an almost identical thread going on a very similar situation with a 261 engine. I'm not comfortable with any crankshaft that's ground smaller than .020" undersize. I'd reccomend replacing the crankshaft with one that's standard diameter, or reground to as small an undersize as possible, and replacing all the rods with new or reconditioned ones. The margin for error is so small as to be virtually nonexistent. No sense stacking the deck against yourself with parts that have failed once already. Also, do a total teardown, including removing all the oil gallery plugs, and brush and pressure wash all the oil passages. Even a tiny bit of debris in an oil passageway can cause another failure.
Jerry

I'm not near experienced as you guys but thought I'd share a story about my dad's old Ferd truck.
After tearing it down, we saw that the engine got so hot, one of the rods was totally reshaped from the heat.
Maybe your blackened rods were overall warped out of square?
Jerry W

Anyone know where I can find information on decoding the block serial number on a 235? I found a motor that the casting # says it is a 58-62 but would like to know more about it. The serial # (stamped on the pad by the distributor) is FII25J.
Thanks for the help fella's.

Scroll down to the bottom of this page, may be of some help
http://chevy.oldcarmanualproject.com/models/index.htm

No listings for anything newer than 57 there. But thanks anyway.

Cayo - that was the wrong place to look, try here, any shop manual for the years you list .... or check at inliners

Bill

catoRV,

Your engine number FII25J breaks down as follows;

F = Flint

11 = November

25 = Day

J = 235 w/ 3-speed trans found in 3000 Series trucks.

The first year they used this type of serial number was 1957, so it's a 57 or newer engine.

Hope this helps,

Mike B

Thanks Mike B.

Well tesaga continues.
After checking everything in the rotating assembly we found that not only were the big ends of the rods hammered out but they were also sightly bent. Worst one was about .004".
OK so I find another motor (from a buddy) to get the crank and rods out of hoping to only have to polish it or at worst grind it .010 on the mains and .020 on the rods, I can live with that.
Everything was going good until we got the crank out and found RUST! The journals will clean up but the problem is the rear main seal surface. Rust pitted and the concern is that it won't seal.
This is really starting to get depressing as I just haven't been able to find many motors, good or bad around my area.
If anyone has a usable 235 crank 1955 or newer and your close to SW lower Michigan I would be willing to buy/trade and make the drive. I've got an extra 848 head now that could go to a new home.

Put a Speedy-Sleeve on that rear main seal surface and press on! They're available in virtually any size, and I believe that particular size is the same as a Ford Powerstroke Diesel. Of course, you could go ahead and get the back of the block machined for a lip seal and avoid the problem of rear main leakage altogether. I'm in the process of getting set up to do that little operation- - - -just have to get a surface plate reground and drilled to fit the back of the stovebolt block to serve as a mounting surface for my Van Norman boring bar.

Edit: SKF "Speedi-Sleeve" #99386 or 99387 will solve the pitted shaft problem. It should work very well with either a neoprene lip seal or a rope seal. Have your machine shop polish the seal surface down about .002" undersize and install a 99386 sleeve with LocTite. Problem solved!
Jerry

A small amount of pitting is not a problem if a rope seal is used or if a lip seal happens to miss the pits. If you are getting the crank ground they can clean up the seal area also. Turning down that area means a rope seal will need to be used.

Jerry that is the best news I could have heard today! I'll be heading out to the machine shop tomorrow to check on the progress with my Speedi-Sleeve info in my pocket! Thanks for maybe helping me to get a good nights sleep tonight.

Chuck

Been a while since I updated this as there hasn't been anything really going on with it.
I did make the decission to buy a remanufactured crank from Northern Auto Parts (about $280.00 after the core refund gets back) and we're using the rods from the parts motor with nw bolts this time. I just don't want anything going back in this time that I can't say is the best I could find.
Crank should be here this week and the rest is ready to go so I'll let you all know how things are going.
I do have another 58-62 235 (or at least a block, crank that needs turned and a nioce 848 head) for a future build or?