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Mon Nov 02, 2009 10:47 am

im glaad to say the rebuild went well, just one question. the engine is complete except for the carbs and the starter. i was wondering if i could start the engine if i poured a little fuel down the intake ports and turned the engine over with a wrench if it would fire so i know it would start? but i was going to try this after i put the new coil ad spark plug wires on and hooked it up to a battery.

Mon Nov 02, 2009 10:50 am

if/when it fires, how do you get the wrench off? =)

Mon Nov 02, 2009 10:55 am

Sounds like a recipe for a wrench flying across the room at high velocities, don't do it! You don't mention what kind of engine it is but you should have a test bellhousing with a starter in it if you want to run it on the floor. Some say they have done it by kicking the flywheel or wrapping a rope around a pulley or flywheel but that's kinda hokey IMO.

Whatever you do have someone video it, it may be entertaining :P

Mon Nov 02, 2009 10:56 am

ill just run like hell :lol: i havent really given it to much thought yet but i would'nt put that much fuel in im not sure.

Mon Nov 02, 2009 10:58 am

If it kicks back and breaks your hand you'll be sorry, like I said....VIDEO!

Mon Nov 02, 2009 11:00 am

:lol: good point. i was just wondering if it was possible to start it without the carbs. and btw because you were asking it is a 1975 1.8l.

Mon Nov 02, 2009 11:07 am

also would 34 PDSIT-2 carburetors be correct for this engine?

Mon Nov 02, 2009 11:11 am

You'll need the carbs to do the 20 minute initial run in. Don't worry about the idle. Just keep varying the RPM between 2500 and 3500. You not only are wearing in the rings, but the cam and lifters as well.

Best Regards - Andrew in Austin, TX

Mon Nov 02, 2009 11:17 am

ok thats good to know thank you.

Mon Nov 02, 2009 11:23 am

I hate those why-would-you-even-want-to-do-that answers, but honestly... what good is it going to do you to start an engine without a carb on it? It will run for 4 seconds and then what have you accomplished? B-daddy is right about the wrench too. That's the first thing I pictured, was a wrench going right through your wall, if not your teeth.

I guess maybe if you are trying to bench test your rebuild, but I'd think that if you did it properly, you should probably be pretty confident that it will work.

And I doubt anyone has the ability to crank an engine over enough to start it by hand anyway - especially with new rings! With your arm you will get a quarter to half-turn at most, unless you put some kind S-shaped jack wrench on there like an old Model-A. Man this is good stuff - yeah, do a video, but wear a full-face motorcycle helmet!

Mon Nov 02, 2009 11:28 am

i do only want it to run for like 4 seconds. but i was worried about the wrech part. i was just wondering if i could run it with he carbs off, i just wanted it to spark and turn over to see it can do it and nothing is stuck. im ordering the carbs. and i can turn the engine over with a wrench all the way over. which is why i was wondering if i could get it to spark without carbs. but its a breaker bar wrench on an extension onto the crankshaft fan bolt.

Mon Nov 02, 2009 11:31 am

I would suggest leaving off the carbs and installing a mechanical oil pressure gauge and spinning the alternator with a drill until you develp oil pressure on the gauge.

That is what you want to check IMO.

Mon Nov 02, 2009 11:33 am

thank you for a straight answer that sounds like the good way to do it i will try this sometime.

Mon Nov 02, 2009 11:40 am

Leave the spark plugs out also.

Mon Nov 02, 2009 12:10 pm

Randy in Maine wrote: I would suggest leaving off the carbs and installing a mechanical oil pressure gauge and spinning the alternator with a drill until you develp oil pressure on the gauge.

That is what you want to check IMO.

I would have never thought of it, but I like this method of checking oil pressure prior to the initial start up.

Best Regards - Andrew in Austin, TX

Mon Nov 02, 2009 1:07 pm

aryue wrote: 20 minute initial run in. Just keep varying the RPM between 2500 and 3500.

Recipe for a destroyed engine. 2,000 RPM yes. Higher- no.
On the other hand without knowing what the "rebuilt" means it might not matter that much anyway. If it was built following good instructions like Tom Wilson's book then the book also has explicit start-up instructions. I do mine on the ground with the trans on it but in the bus works also.
Don't even try to start it until it's ready for the initial run in. Just put it in the bus and don't even attempt to start it until doing the run-in. As far as seating the rings there is a driving procedure to use. It accomplishes absolutely nothing to start it for a few seconds to see if it will start. Instead it will probably harm it. And that's even ignoring the death wish from a flying wrench. Just install it.

Mon Nov 02, 2009 4:15 pm

Desertbusman wrote: aryue wrote: 20 minute initial run in. Just keep varying the RPM between 2500 and 3500.

Recipe for a destroyed engine. 2,000 RPM yes. Higher- no.

John Conolly's run in procedure shows 2,500 - 4,000 RPM.

http://www.aircooled.net/gnrlsite/resource/articles/engnbrkn.htm

I only do 3,500 RPM for brief intervals - but. as you say or didn't say, the rings seat better on the road under a load while varying the throttle.

Best Regards - Andrew in Austin, TX

Mon Nov 02, 2009 5:01 pm

Randy in Maine wrote: I would suggest leaving off the carbs and installing a mechanical oil pressure gauge and spinning the alternator with a drill until you develp oil pressure on the gauge.

That is what you want to check IMO.

Randy, have you actually tried this? I would think it would require a very powerfull drill. If this works I may try it myself.

Mon Nov 02, 2009 5:10 pm

I think removing the spark plugs is key here, which Randy added a few moments later.

Mon Nov 02, 2009 7:17 pm

I agree with aryru. (the longest 20 minutes ) period.