OldIHC

I don’t usually don’t believe in coincidences. I may have to change my mind but value OLD IHC opinions. I have a 49 KB1 that has been running very well putting around town and doing well at 50 mph with a Ford 373 rear. I DECIDED TO FRESHEN THINGS UP A BIT by painting the manifolds with some high temp paint. I removed the accelerator linkage plate to get better access . While the paint was drying I replaced the Champion plugs with Autolite 303’s. Still had some lag time so I made a gasket washer for one of the fuel pump bolts that was weeping some oil onto the pump.

The next morning after the paint dried, I replaced the throttle linkage and fired her up! UH OH !! A loud metallic sound occurred in time with motor revolution. Shut her down and pulled the plugs, turned it by starter motor ..no noise. Replaced plugs and ran it again..same loud noise. Ran it without fan belt..same noise. Pulled clutch inspection plate just to eliminate anything there..nothing. I’m thinking maybe a valve or rod bearing although it doesn’t sound deep enough for the lower end.

Very strange that it would take place after a SPRUCE UP.

BK

I know it is difficult without hearing the noise but it is clanking loud enough not to run it without further inspection.

Is it possible a longer sparkplug might be touching a piston top? Is the engine a flathead?

Engine is a flathead and to eliminate that possibility I looked at all the plugs but also put the originals back in.
Good thought . Thanks

Is there a remote possibility something might have fallen in the engine while the plugs were out?
I like your diagnostic elimination order.

my starter once in a while hangs up on flywheel sounds horrible

I turn in off and start it again, no noise, maybe a possiblity

First thought was maybe something did fall in . Always a possibility but I can’t think of anything. I vacuumed each plug hole ( doesn’t mean I retrieved anything ) . Thinking of things ..maybe When I pull the plugs tomorrow for the compression test I’ll try a small magnet. As far as the starter hanging up I did pull the inspection cover over the clutch and flywheel.

How far did you remove the fuel pump , is there a wrong way to install it ?

Did not remove the fuel pump.Pulled one bolt and added some gasket material In front of the washer. As I trace my steps there are some possibilities; I removed the air cleaner for easier access and stretched a rubber glove over the carburetor (maybe the glove had something stuck to it) to keep out debris. Another possibility is when I reinstalled the air cleaner that it may have had something stuck to the bottom. I had a magnetic dish on the head to hold the accelerator linkage stuff but the plugs were still in at the time; I could have left something on the head when I removed the tray but I don’t recall seeing anything and I had all the parts when I put the linkage back together .

Started early in the garage today and the wife asked me why and I explained how I was tracing what may be a major valve/rod problem she asked how that could be as I have gone nowhere. She’s probably right (more often than not)but something ain’t right and it’s probably due to my lack of observation during the SPRUCE UP. An old friend and a terrific mechanic reiterated to me that old saying; “ IF IT AIN’T BROKE,DON’T FIX IT “ I’m now thinking that the unpainted manifold looked mighty fine the way it was.

Compression test complete: cyl 1=110. 2=90. 3=103. 4=105. 5=94. 6=100. These readings may be +/- because gauge digits are not that fine.These are cold readings , all plugs out.

Looks like no valves are stuck open.

I did find a small ball point type spring hidden by the heater water cut off. Maybe something else was also there that slipped into 5/6 cyl.

Pulled the head without removing the hood. I was surprised how easily it broke free; a couple taps with a rubber mallet and it was good to go. Lifted the front and placed a piece of 2x10 under it and then a piece of 2x4 closer to the rear. Had the driver’s side fender draped inside and out with a moving blanket. I was pleasantly surprised; lighter than expected.

On the bench and seeing the piece of washer stuck in the squish chamber made perfect sense. It flicked off with touch of a fingernail. Looking at gasket and cylinder patterns was interesting. #3 cylinder had some splotches of clean iron and looked as though it may have burned a little water vapor. Also the cylinder appeared a little rusty and not the even carbon coating of the rest. When running , the engine did not misfire on any cylinders so...I’m thinking maybe a very slight amount of water got into the chamber. I certainly saw no indication of water in the oil.

Checking the head for flatness today as best I can with the straight edges I have. If the feeler gauge disappoints I’ll be calling around for milling prices. Don’t have a clue about milling costs today as I’ve been away from this stuff for 50 yrs.