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 Posted: 11-25-2016 10:40 pm
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Screenplay

 

Joined: 07-12-2013
Location: San Francisco, California USA
Posts: 121
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I just got #18341 running. This is a car I picked up for parts - the owner parked it in 1988 and it didn't move until I brought it home over a year ago. After recording cold cylinder psi of 125-135, I thought it might be worth seeing if it could be driven again.

After rebuilding the ZS carbs and distributor, changing rubber, other parts and with new fuel, it clicked over after only 20-30 seconds of trying (with a little help from some starting fluid) - an immediate 80 lbs of oil pressure, vacuum at 15 in (shaky) and a pretty rough idle. Let it run for about 5 minutes before shutting it down and before the blue exhaust smoke overtook the entire house. I expected a lot of crud in the exhaust, but it was billowing blue. I then borrowed a friend's two compression gauges (just to be sure) which both showed between 85-100 psi across the board. Squirting motor oil in the cylinders increased the readings by about 5-10 psi. I've never been too sure of how much oil to put in, but I was certain to apply it at the top of cylinder wall so it could make its way around the top of the piston. I had started down this road becuase I thought compression was good, but by the end of the day I had chucked my trusty 30 year old Milton compression gauge in the dustbin.

There's nothing like an excuse to buy a new toy so I got a nice quality leak down tester. Readings, with 100 psi in, showed a difference, or loss, of 35-45% on all cylinders. While there was some sound coming from the carbs and exhaust, by far the loudest hissing was coming from the crankcase. No bubbles in the radiator coolant.

It would seem the engine is tired and would benefit from a complete rebuild. But I can't do that right now, nor on this particular car. This is one I'd like to get running on a rather extreme (low) budget. Does it sound like rings? Can I get away with just new rings? What measurements would I need to determine that? It would be great to be able to reassemble with existing rod bearings, perhaps not dealing with the crankshaft and letting an expert look at the head. I haven't opened up an engine in over 30 years and I have another JH project that will get my full attention. I need to see this one on the road, if for no other reason than to get some payoff for all my time, and maybe to show friends, family and neighbors that I just might know what I'm doing.

Clinton

Last edited on 11-26-2016 12:20 am by Screenplay