Update-1936 LB rod journals and freeze plugs

[denson1932]

Thanks to all who offered technical info and help on the tight rod caps-to floating bearing dilemma...the fix was to bring the rods back to the machine shop as they were not re-sized to the correct spec. Luckily they were too small not too big....the confusion factor was that the first two i installed were not tight becsuse they were honed correctly! A few thou makes a world of difference!
Now what to do about the 4 open freeze plug holes along the block's oil pan gasket rail...I discovered a penny is a perfect tight fix i will use a generous amount of #2 Permatex but should i also stake them in?

[BrianCT]

NAPA has correct size plugs.Zinc pennies will be eaten up by electrolysis.

[JM 35 Sedan]

Originally Posted by BrianCT

NAPA has correct size plugs.Zinc pennies will be eaten up by electrolysis.

You are correct about today's pennies being composed of mostly zinc and they will deteriorate very quickly. However, if you find pennies made prior to 1982 they are mostly copper. In either case, finding the correct plugs at an auto parts store sounds best to me.

[Brian]

I'm in New Zealand, and a [NZ] 5 cent piece is just the right size for this very same application. Nz went to decimal currency in 1967, prior to that we used the Imperial pounds/shillings/pence. The earlier equivalent of the 5 cent piece was a sixpence. These earlier coins contained a fair amount of silver. I have squirrelled away quite a collection of sixpences, and use them to renew the freze plugs in every engine I build. Sick puppy I am, I use the same vintage sixpennies as the year of the motor! Thing is, even taking into account inflation, I could not buy modern freeze plugs anywhere near as cheap. Wierd or what? Brian

[Barry WNY]

I tried coins for fit but also knew I wanted it right, found the soft plugs. I used a tiny bit of permatex black dope around the rim & on top after in place. I plan to plug the exhaust ports to the intake, considering making a "coin" out of stainless.

[Walt Dupont--Me.]

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Most parts stores have freeze plugs, there 3/4in. dish plugs. I usually smear some RTV on the ledge and install the plug and flatten it out with a punch. We've all used pennys in the exh cross over on top of the block, but I've seen alot of them blown out the exh pipe. I use a regular cup type block plug, they fit snug and will not blow out. Walt

[rotorwrench]

If a guy is building his own engines and wants to take the chance of a leak, no problem. A jobber performing a rebuild for a customer has to hedge his bets and get the best stuff for the job that he can. A quality freeze plug will expand when installed where a fixed size "coin" has to rely on snugness of fit, some appropriate sealant, and the oil pan to hold back the hot water. Warranty work is not affordable to any jobber that I know.

Kerby