After purchasing my car 2 years ago from the son of the original restorer and 2nd owner, I was forced into a major decision. For a 35 year old restoration, it was in great shape except for one annoying problem- worn out rod bearings. She would knock like an angry woodpecker when under load going up hills.
If I lived in a flat state like Florida or Kansas, this project would not have happened and I would not be sitting here typing this as she sounded and performed fine on straightaways.
The connecting rod and main Babbitt bearings on these straight 6 cylinder stovebolt engines were fitted with shims so that as the engine wore, they could be easily removed to reduce the excess clearances that resulted. These are incredibly thin, about .0002” thickness as I recall.
The problem arose when I attempted to adjust my loose rods. I discovered there were no shims on the rods and only a few left on the mains. Apparently they were already removed throughout the car’s lifetime when needed.
The previous owner did not disclose this to me nor did I have the foresight to inquire. The original rings were fine. The head was rebuilt once before so maybe he accepted the knock, knowing it was a major job and investment to fix.
Convince my wife $6,000 for a total rebuild was in her best interest. That failed.
Plan B was proffered. If she agreed to the rebuild, I would consent to her unlimited purchase of shoes for the next 5 years, an equal financial trade off. That worked.
Back in the day every town had a repair garage that could pour Babbitt bearings. The process most likely borrowed skills used in blacksmithing. Mixing different metals and alloys, heating, cooling, etc. was basic stuff, but with exacting tolerances.
It was not looking good after searching around for the few specialty shops still offering this service within a day’s drive. I somehow finally stumbled upon an older Hemmings article that profiled a re-Babbitting shop in nearby Willington, CT, Aldrich Engine Rebuilding . After a visit to his shop, a veritable antique machine museum itself, and obtaining a reasonable quote, I was off to the races. I dropped the engine off a few months later, his earliest opening.
My last engine removal and rebuild was back in 1972 when I rebuilt a ’68 VW engine. The test drive was to Washington state AND back starting from New York. We made it in fine shape. If I could do it then I could do it now, so out it came. I bought a decent engine hoist from Harbor Freight, grabbed a friend, pulled it, took tons of photos, and delivered it to the shop in Wilington. This was March, 2016.
I was told 6 months by the rebuilder. 6 months turned into 12. Finally, after much growing anxiety, it was done.
My advice to people considering such a project: Be patient. These shops are mostly one-man operations and not their primary source of income. Consequently you must work with them and have other car projects going to stay focused. I kept busy doing odd repair jobs, disassembly of components, cleaning, painting, and buffing things.
What saved me from going crazy was to take the plunge into auto body repair and painting. Having never picked up a spray gun (I’m a rattle can guy), I watched videos and read up on the subject. My car’s old acrylic lacquer was finally lifting off, so with little funds left for a professional job, I picked up a HVLP gun and gave it a shot.
I can now lay on acrylic lacquer with reasonable confidence, knowing if I mess it up, I’ll just wet sand it off and try again. The problem is it will be banned completely in about a year so I bought extra now. The new paints are better, but one needs expensive protective gear and outdoor spraying would not work very well.
All 6 connecting rod bearings and 3 main bearings were re-Babbitted with Grade 2 Babbitt, an alloy of about 90 percent tin, 7.5 percent antimony and 3.5 percent copper. Lead only makes up less than 0.5 percent, along with iron, arsenic, bismuth, zinc, cadmium and aluminum.
This was the most expensive component of the job. It’s very time consuming, all hand labor.
New aluminum pistons/rings were ordered from Kanter in NJ, new SS exhaust, and intake valves from Marx Auto in WI, new tappets and other parts from various antique suppliers. They were drop shipped to the rebuilder for assembly.
A complete cylinder head rebuild was performed. The block was hot tanked, but maybe due to restrictive EPA rules I still was able to find and extract rust scale after it was done.
The entire rotating assembly was dynamic balanced at a local performance shop. This was not cheap ($500) but strongly recommended. None of my old rods weighed the same :)
An NOS harmonic balancer and an NOS vane type oil pump were installed. This was important since this engine is a splash type lubrication system, not pressurized, except on the center main. The oil fills three troughs in the pan and is then splashed around by “dippers” on each rod end, a primitive but adequate system for low revving engines.
I decided on Lucas 10W-40 detergent oil. It has fair amount of Zinc (ZDDP) necessary for flat tappet engines but I also added a few ounces of zinc additive to be safe for the initial break-in.
That’s about it. I won’t bore readers with the other 100 minor projects, but for now, as of this writing, I look forward to a successful road test this week, then re-joining the gang in a few shows and outings this year. I had an exhaust valve decide to stick but I think I fixed it by burnishing it in place with a cordless drill. Re-builders are known to set valve guides too tight. I'm learning.
Out of respect to Murphy’s Law, my AAA towing package has been renewed and upgraded!!
And my wife’s shoe collection continues to grow...
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