Disabling ignition system

P

Peter Mahr

Daily Driver
I am installing an 82 FI engine in my 74 x. I would like to crank the newly installed engine to establish oil pressure before I install the spark plugs and actually start (hopefully) the engine. As I understand it, I should disable the ignition system so that I don't damage it while cranking. On my '74 breaker point ignition system, I simply grounded the ignition coils center wire before it entered the distributor. Is this an acceptable method for the newer, electronic ignition, fuel injected '82 engine, or is there another, better method? Thank you for your help.
 
Yeah, PULL the High Tension lead out of the coil, but...

first turn it over by hand... plugs out and oil squirted in the cylinders.

Put the car in 2nd gear and roll it slowly forward. then in reverse and roll it backward. DO NOT roll it in such a manner that you are spinning the engine BACKWARDS! Its just not right...

Then engage the starter and spin the engine and watch for the Oil Pressure light to go out. Maybe squirt some more oil in the cylinders and spin it again.

Reinstall the plugs, use some ether (starting fluid) and squirt that into the FI intake. Then let her rip.

More detail if needed...
 
On page 55-7 of the shop manual, FIAT recommends that for situations where you want to turn over the engine with the starter but you do not want the ignition system active (such as for compression testing and in your case for priming the lubrication system), that you disconnect the distributor pickup.

It specifically states that you should NOT (among several other things) crank the engine with the high voltage wire disconnected from the coil.

Sounds like they want you to prevent the ignition system from generating a spark rather than preventing the spark from reaching the plugs.
 
priming before startup

best case.... grab an old distributer and remove the shaft, strip it clean and use a drill to pre- prime the oiling system. with the cam cover off, you will see some oil, and the filter will be full. yea, if you have the dist in and timing set...pita. but we did on all the NASCAR motors my cousin and I built before the first startup . and if you have access to EOS,
(engine oil supplement) made by GM, wise to add that before the priming process.
mikemo
 
That works on American engines

mikemo90 said:
best case.... grab an old distributer and remove the shaft, strip it clean and use a drill to pre- prime the oiling system. with the cam cover off, you will see some oil, and the filter will be full. yea, if you have the dist in and timing set...pita. but we did on all the NASCAR motors my cousin and I built before the first startup . and if you have access to EOS,
(engine oil supplement) made by GM, wise to add that before the priming process.
mikemo
Click to expand...

But not the Fiat SOHC. The oil pump is driven off the Aux shaft, which is connected to the timing belt. No way to spin the pump without spinning the crank/cams.

Pete
 
Mikemo is stuck in the 60's with his Chevy Van...

but it is the best way to prime the engine... if you can!

I have started engines new and old (sitting for years) using the method I described and have been successful in every case with no harm done.

Even Chevy's...
 
priming

yes, the pump is splined as is the distributor, and the gear off the aux shaft combines both. you can pull the drive out and run the pump manually.
mikemo
 
Thanks for all of your replies!

It seems that Dan Sarandrea has hit the nail on the head - just unplug the distributor pickup. This prevents the control module from making a spark in the first place, and all is fine. If in doubt, read the book! Thanks for the page reference, and thanks to everyone who gave me more info to help get the engine started.
 
Warning ...

Energizing the circuit could make a spark, (i.e. a single spark) regardless if the dizzy pickup is unplugged or not.
So, to be sure, I would recommend removing the feed wire from the + side of the coil.
 
I'll have to take another look

mikemo90 said:
yes, the pump is splined as is the distributor, and the gear off the aux shaft combines both. you can pull the drive out and run the pump manually.
mikemo
Click to expand...

Been a while since I tore apart an SOHC engine, but what you say makes sense now. I guess it's not really that different than an American engine, the aux shaft just takes the place of the camshaft and everything else more or less works the same way... hmmm. I learned something today!

Pete
 
Peter Mahr said:
It seems that Dan Sarandrea has hit the nail on the head - just unplug the distributor pickup. This prevents the control module from making a spark in the first place, and all is fine. If in doubt, read the book! Thanks for the page reference, and thanks to everyone who gave me more info to help get the engine started.
Click to expand...

And as an added bonus, this prevents the fuel injectors from firing as well. The ECU only fires the injectors if it sees pulses on the coil primary.
 
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