1930 Essex Timing

30essex

I'm still having problems with my 1930 Essex sedan. I thought I had it running fine after cleaning and adjusting the carburator but now it won't run again. I'm thinking that maybe the timing chain has jumped a notch. How can you tell if this has happened? What is the best procedure for getting the cover off, etc. Any help would be much appreciated.

Geoff

Usually if the timing chain is worn or stretched it will flip a notch on the accessory sprocket, not the valve sprocket, so it is unlikely the valve timing will be altered. However, if worn, the valve timing will be considerably late. To check the amount of movement in the chain, you grasp the generator rubber coupling, and twist it back ond forth, hard. There should be virtually no movement, so if you get more than 1/8" back and forth movement it indicates stretch. It may be the chain just needs adjusting. You remove the two inner bolts, loosen off the outer one, and bring the notched adjuster towards you at the top to tighten the chain. If the chain is still within it's range, it will tighten right up. If it is worn beyond redemption it may go right over the top and start loosening off again, in which case it will have to be replaced. If noisy after tightening, you will have to back off a notch. To check the ignition timing, locate the U.D.C. mark on the flywheel and align it with the mark on the rear engine plate, right hand side. On U.D.C., the distributor points should be just opening, with the rotor pointing at the relevant cylinder's terminal.

Geoff.

30essex

Thanks Geoff. I checked the play on the chain and it is about 1/8 in. which is what the original manual says it should be. The timing was off and I reset it using the following method. I lined up the mark on the flywheel, turned the ignition on and turned the distributor until there was a spark between the points. This should be where the points just open. It seems to run ok now.

Geoff

I would try tightening the chain anyway, just in case you ae not twisting the coupling hard enough. Normally the chain cannot jump over a notch if the adjustment is okay, but it can still happen if the chain is stretched. For optimum running on modern fuel you need to adjust the timing with a timing light, and set it two teeth before U.D.C. idling.

Geoff.

30essex

Thanks again Geoff. I tried tightening the chain. When I put it as tight as possible, the motor would hardly crank over. I loosened it one notch and then there was a lot of timing chain noise. I loosened it one more notch and now it sounds nice and quiet. Is there a special tool or technique for turning the cam? I did it with a visegrip and and a screw driver and found it quite difficult.

I checked the timing with a timing light. I couldn't see the teeth through the inpection hole but the UTD mark was about half an inch below the pointer at a fast idle. What should the idle speed be when setting the timing? I took it for a drive and it still hesitates when it gets up to about 40 mph. Any other ideas?

Arend

Geoff

I would check the points gap, it could be too wide, causing ignition failure. Also you need to check all connections to the coil and distributor, and for resistance across the ignition switch. Preferably use a volt meter at the coil, checking for full 6 volts with the ignition on, and the points closed. Or it could a weak flapper valve spring, or blocked main jet, causing fuel starvation. The ignition timing is about right, and the chain is obviously not stretched beyond reason, so you should not have any problems there. The screwdriver and vice-grips is the usual tool for this job!

Geoff.

30essex

Thanks again Geoff. I checked everything and did find a couple of problems. The negative ground strap was really bad so I replaced that. It now turns over faster with the starter. I also found that the electroloc was shorting out if you wiggled it. I think possibly the air from the fan at high rpms could have caused this to vibrate and short out intermittently. I drove it a couple of blocks and it did fine at 45 mph. One of these days I'll take it down the highway to see how it does at 50 mph. for a longer distance.

Back to question of the timing chain possibly having jumped. From reading another post today I learned that if the chain has jumped then compression will be low due to the valves not being closed at TDC. Last year when I checked the compression I was getting readings of around 50 - 55 which seems to be very low. However the motor seems to run fine and has a fair amount of power considering it only is supposed to have 55 hp at 3600 rpm. It has a lot of lugging power at the low end. What do you think?



Arend

Geoff

The post on timing chains referred to the large post war motors used in Step-downs. On the Essex, there is no possibility of it jumping over the cam sprocket. To check the valve timing, remove the front or rear valve cover, insert a .006" feeler gauge in the second valve from the end (inlet), and very carefully wind the engine over with the crank handle, observing the U.D.C.1-6 mark at the pointer in the rear engine plate. With a new chain, you should feel the feeler gauge go tight about an inch or so past the mark, ( about 3 flywheel teeth) but with a worn chain, it will be up to 2 or 3 inches past. Compression readings depend on the state of the rings and valves, the temperature, and the cranking speed, and the main thing is that they are all pretty well equal. To me it sounds pretty normal. Good luck,

Geoff.