After a lot of fooling around with the '71 142 we still can't get it to run. We checked the valves to see if they close in the right order (rocker arm cover off, check for both rockers for each cylinder to be "rocking", checked the plugs - they fire in the right order (watched 'em out of the head). Valves for #1 both closed at TDC, same with other cylinders.

The engine "tries to start". We get complression and it sometimes "coughs" as if to start and it will run for a whopping 10 seconds some times. When we examined plugs, 2 and 4 were dripping wet after trying to get it started. 1 and 3 were dry but sooty (if that's a word"). After drying and cleaning the plugs we got car started and it ran for several minutes until I screwed things up by lowering the needle seat on carb #1. The car stopped. 'cleaned plugs again and car ran for a while -several minutes - before we shut 'er down. When it was running it was rough, but sounded like an old Volvo engine should (first time since my son got the car). This afternoon it wouldn't start. It just coughs.

Any ideas? How come plugs 2 and 4 were wet and 1 and 2 dry. I would have expected adjacent plugs (1/2, 3/4) to get wet as pairs since the cylinders are served by the same carb.

What am I missing?

Any help would really be appreciated.

Jim Hampton

I presume you've got double SU's? If there very worn/not synchronised they can cause *extreme* rough running, I can tell you...
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P131, '65, B20B+M47. P131, '69, B20E+AW71L+LSD. (www.tinustechniek.tk)

That's sort of where the trouble began. We converted from a Weber set-up to SUs. It ran ok with the Weber (ok, not great). The SUs have been re-bushed and are in good shape. As far as synchronizing, the best I can do at this point is a rough setting intended to get us going.

Another bit of info - it has a Crane ignition which was put in before the carb conversion and it was doing well. Monday I'll check to see if it's functioning properly and check out the things you and others have suggested. The Crane system could have gotten bumped with all the stuff we've done - tranny conversion, carb conversion, timing gear, push rods and lifters, setting valve clearances (maybe that's all, I can't remember).

Thanks, guys. if there's any other info or other suggestions, I'll appreciate it.

Jim Hampton

before you start messing with the carbs the timing/ignition and valve clearance should be dead on. I agree with the other poster, new cap and rotor, also consider new S plug wires. You alos need to check for the dwell on the contact points when you do the timing. Poor dwell on a worn distributor will cause various unhappy symptoms. Which brings me to the final point, some of these ol dizzies are just too sloppy to give you a decent reliable spark for more than 40 hrs or so on a brand new cap and rotor, there is too much play in the shaft to set up consistent dwell, and the wobbling shaft also wear out the cap and rotor prematurely.

Those plugs are adjacent in the firing order in the cap. Check the cap for arcing or just replace it with a known good one. Perhaps it sounded rough because it was running on just two cylinders? Static time the thing to 10 degrees before TDC too.

Also check if the distributor shaft wobbles.
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'74 145e T-5 'Orange Alert'

Hi. Please, just also check the ignition cables. The following protocol help me with diagnosis:

a) Midnight test: Start on night without light and with the engine bay open, if you see or hear sparks flying on the ignition wires, you need to change all cables. If you see a corona aura around the wires, you need a more diameter cables or your cables are too old or marginal (change it). If remain dark, pass the hand over the cables trying to start at the same time, if are safe to pass the fingertips over the cables, they are ok, if you get pinched, the cables need change.

b)Peel back test: Shut off engine. Disconnect wire from spark plug and bend back the boot to expose the wire insulation. If you see a clear line between the exposed and the protected insulation, then the insulation is porous as best and contaminated at worst. On that case, change the wire.

c)Flex test: Remove the wire (test every ignition wire), connect a multester as ohmimeter (ohms) between both terminales of the cable. Flex the wire back and forth, pullin over the entire lenght. If you feel any britleness or the multitester measurement change as you flex the wire, change the wire.

(protocol source: C. Jacobs, Ignition performance systems. Hpbooks, 1999).

Cables will be changed every 4-5 years. No one include it on the maintenance schedule.

Happy volving

Joaquin
Rojo 121 Amazon
Lima Peru