Yes I would like to know how to check the rod bearing clearances too

The clearance should be 0.001-0.002". The process described in the Repair Manual is the best I have found. It uses a small hammer to lightly tap the rod side-wise on the crankshaft. Since the crankshaft and rod bearing may be worn off center it is best to check the fit 360 deg. around the crankshaft. Can be done by rotating the crankshaft and rod before piston is attached. Caution: Using plastigauge is only an indicator with the soft babbitt not an accurate measurement. 

I agree with everything that Chip said.

I had some engine knocks to deal with after my 1928 engine rebuild in 2017. That part of the story is here: https://vccachat.org/ubbthreads.php/topics/403941/re-resurrecting-a-28-4-banger.html#Post403941

FYI, here's the beginning of the engine rebuild thread: https://vccachat.org/ubbthreads.php/topics/386451/resurrecting-a-28-4-banger.html

Let us know what you found and how you fixed it. 😉

Cheers, Dean

thank you i'm experinced in fitting and lapping plane bearings. is there a bearing materal that can be used as replaceable bearings..

No modern replacements that I know of. The early six cylinders can be machined for insert bearings but I don't know what inserts they use. I suspect that there could be some that could be made to fit. When there are no people pouring babbitt something must be found if we want to keep driving the older cars.

Ok , guess I'll start fitting from spares

started it up today ran for 5-10  minutes all good run some more tomarow.

will see what happens, ill try the little at a time approch.

john

hello, took on another ride (after warm up) started backfiring and not running very well, returned after 2miles.

checked ign points ok looking at fuel filter in front of facume tank looked like air was cycling on and off with the fuel.

have newer system with two needles how do you tell if working right. should the fuel cap be vented?

Not sure what you mean by two needles. Yes, your cap should be vented.

Try checking the basics first, e.g.  clean spark plugs, check condenser, rotor and distributor cap, coil, leads.

Check tappet clearances and also the oil mat on the top of the rockers is in good condition and well-oiled and oil in the cylinder head reservoirs.

Try check clearing the fuel line from vacuum tank back to fuel tank.

Check the floats in both the carburettor and vacuum tank are not leaking and filling with fuel. needle and seat etc . 

2 last quick checks, disconnect the fuel line at the vacuum tank and check with your finger that you have good suction going into the vacuum tank when it is running and also the advance retard is working properly eg fulling advanced after starting. 

2 Needles?    

@rick-barbour   in prosses of doing so far so good. the two needles are inside of vacume tank,that seems to be working.

going to take pan off and check rod brg after replace and run in of used rod. john

well, ready to start driving again, all look good rods are tight. trying new spark plugs.

need to put air cleaner on exhaust side. john

drove again still backfiring gets better when warm, bearings seem to be ok.

keep trying befor cold. john

The timing might be off.  I set the timing differently than the shop manual suggests. I set the time with the spark lever in the full retard position (top dead center - TDC) for easy starting and let the advance lever do its thing. I do not check to see if the spark lever (while fully advanced) is on 25 degrees before TDC.

Here's an article on the old forum on that subject: https://vccachat.org/ubbthreads.php/topics/391672/1927-timing-off.html

Hope this  helps. Dean