Really dumb question from the newbi

[Weav]

Hi all. I love this site, especially since I am an aviation electronics technician and although I live on carriers, I have no clue about boating. With that being said, I've been reading all morning about backfiring and timing issues. My '83 70 hp 'Rude (E70ELTC) cranks all day long, but won't fire up. If I give it a bit of starting fluid thru the carbs, it'll hickup and spit and try then go right back to dead once all the fluid is burned up. Now, I have been reading thru my Seloc and trying to figure out which cylinder is #1 and what exactly TDC is. I've gathered TDC is when the piston is the closest to the head. So that would be where the spark plug is, right? (I told you dumb questions to be asked) When I pull the plugs and rotate the flywheel so the piston in top cylinder (the #1 cylinder I hope) is at the highest point and then look at the timing marks on the flywheel, they are 180 degrees out. In other words, the timing marks are at the back end of the motor. Would that indicate a timing issue? Sorry for the dump questions, but I can wire up an F/A-18 Super Hornet to drop a 2000 bomb on the hood of a Volkswagon from 24,000 feet, but have no clue when it comes to motors. Thanks in advance for insight and advice.

**went into the garage and grabbed a socket and checked the flywheel nut torque and that thing came off like it was never tightened down.***

 

[Scaaty]

Re: Really dumb question from the newbi

Best I could tell ya is there is a good possibility the flywheel key has let go. Pull the flywheel, see whats up in there...is/was the key properly aligned?
Do that first, and we can walk ya through the rest...one step at a time

 

[F_R]

Re: Really dumb question from the newbi

Yeah, sheared flywheel key from loose nut.

But never mind that, my hat's off to you guys that are serving our country. I really DO pray for you.

 

[Weav]

Re: Really dumb question from the newbi

Yeah, sheared flywheel key from loose nut.

But never mind that, my hat's off to you guys that are serving our country. I really DO pray for you.

Thank you. I love serving our country and doing their bidding. There isn't a better job in my mind.

Okay, so I've pulled the flywheel. I am assuming I need to pull everything else under it to see this key??

 

[HighTrim]

Re: Really dumb question from the newbi

By the way, TDC is top dead centre, which is closest to the plug yes.

 

[Weav]

Re: Really dumb question from the newbi

i guess when you look before you ask, the answers can become apparent. i found what i think was supposed to be a key. it goes into the crankshaft and the groove in the flywheel?? well, whatever it is, half is in the crankshaft and half is in the flywheel.

 

[mikesea]

Re: Really dumb question from the newbi

bingo,you found the problem,hopefully you wont have too much trouble getting the remaining piece from the crankshaft,I find it easiest to get a punch about the same diameter as the key and tap on one end ,then the other,the key is round on the backside so it should rock out enough to then hit it with a chistle

 

[BoatBuoy]

Re: Really dumb question from the newbi

That key fits into the grove in the crankshaft and the grove in the flywheel mounting hole long enough to torque to nut down on the flywheel while it's in the correct position. If that key is damaged, see your JohnnyRude dealer for a new one. Don't try to use one from a hardware store.

The crankshaft is tapered and fits the taper inside the flywheel hole. Hopefully, the taper hasn't been damaged by the flywheel nut being too loose. Your last sentence is most telling as to why it's backfiring. The flywheel has probably sheared the woodruff key and allowed the flywheel to rotate on the crankshaft. Now the timing is off.

 

[Weav]

Re: Really dumb question from the newbi

You guys are AWESOME!!! Thanks for the help. I'll be back once I get the keys. That's the hardest part...there aren't any real Evinrude/Johnson dealers around here. The only guy who knows what I am talking about lives about 45 minutes away and doesn't stock many parts. Ugh. Oh well. Thanks again for helping me locate the problem. I'll be back so you can walk me through setting the timing soon.

 

[JB]

Re: Really dumb question from the newbi

Ahoy, Weav.

This thread is proof again that there are no really dumb questions.

Thank you for your service. I was an AT 50 years ago.

 

[Dennisanoka]

Re: Really dumb question from the newbi

It may cost you $7 in postage for a $3 part but I'd just order it online if I were you. Unless you want to go fishing tomorrow.

 

[Weav]

Re: Really dumb question from the newbi

Ahoy, Weav.

This thread is proof again that there are no really dumb questions.

Thank you for your service. I was an AT 50 years ago.

JB,

I've been an AT for 13 years and have loved every minute of it. I love meeting and hearing from the veterans of our rate.

 

[mikesea]

Re: Really dumb question from the newbi

the timing will be on once you put the new key in and torque it down to 105 ft.lbs to insure it wont happen again

 

[Weav]

Re: Really dumb question from the newbi

Again, you guys are the best. I am waiting for a call back to see if the guy has them in stock. I am really wanting to get the boat in the water this weekend. I bought it at the end of May for a whopping $700 w/trailer from a guy who knew nothing about wiring and wired the motor all kinds of backwards. We've refurbished the interior, restitched seats, rebuilt the trailer, and this is the only setback at the moment. SWEET!! Just got a call from the guy and he has them in stock. So I'll spend $7 in gas to get on the water tomorrow. Thanks again everybody!!!

 

[BoatBuoy]

Re: Really dumb question from the newbi

You can order it from ishopmarine.com for $3.09, part no. 307480. They could ship it in an envelope for minimum postage, but they'll probably hit you for 4 or 5 bucks.

 

[Weav]

Re: Really dumb question from the newbi

Okay, so you guys got me through the timing issue. So now the next problem I am baffled with. I got the motor to start on the third turn of the key. The problem is it goes straight to ludicris speed as soon as it is started and I can't shut the darn thing down. I pulled the man overboard clip and nothing happened. So I ended up pulling the gas line and starving it. After the thing ran for a terrifying 30 seconds or so at WOT (I do have muffs on), I noticed the throttle linkage had hung up, so I walked up to the motor and rolled it back to low speed idle and the motor complied. So is it normal to rev all kinds of high until warm and why won't it shut down when I pull the kill switch? Any suggestions???

 

[mikesea]

Re: Really dumb question from the newbi

I bet that happened before and the torque is what broke the key,anyway,be sure all the linkages are freeed up so it wont happen again,that can kill an eng bigtime,seems like your kill circut has been disconnected or a wire broke,look for a blk wire with a yel stripe by the powerpack,when that wire goes to ground via the key switch or a push button,eng should stop,sounds like you have a few gremlins your working through,there is a timing plate under the flywheel that provides your timing,those plates often get gummy and can cause yourthrott;e to stick as can cables,insure you dont get wot before restarting ,the overboard clip was probably disco'd because it wore out,just gussing look also for a plug that is disco'd with a wire with marking I mentioned

 

[Weav]

Re: Really dumb question from the newbi

I have read the black and yellow wire on both the engine harness and control harness and they read perfect. I took apart the controls and checked the kill switch...grounded when removed and key in on position, open with clip installed. Seems like everything is working as advertised. I also read out both of the M terminals on the key switch and those read good as well. So I would assume the power pack is bad? Also, I tore apart all of the linkages and installed new control cables. The linkages were gummed up something fierce with grime and grease. I used good ol' xylenol to clean everything up and a little sand paper to smooth out the passages. The linkage now moves like new. So my next question is, the little plate below the timing base that's attached to linkage and the large return spring on the throttle linkage sits all the forward? Is this correct? Should it move relative to the throttle movement? Because right now it sits stationary regardless of throttle movement. Thanks again.

 

[JB]

Re: Really dumb question from the newbi

You might have gotten a thermal runaway, Weav. When revved high with no load some 2 strokes go Diesel from residual heat in the combustion chamber.

Killing the ignition will not stop a thermal runaway. If you are lucky, cutting off the fuel will stop it. If you are unlucky it will grenade and stop forever.

 

[Weav]

Re: Really dumb question from the newbi

I am going to apologize in advance for the long post, but I felt it was necessary to explain everything.

Okay, so I took the boat to the river to try it out since I found a few more things messed up. The wiring from the rectifier was jacked up, for one. Anyways, I start the thing up and again, the damned thing takes off to WOT. I checked the linkage to the carbs and they haven't moved an inch, so this thing is just going all kinds of crazy without any input from me. I starve the thing of gas and let it run itself out (it still won't shut down any other way). I changed out the power pack, gave it one pump with the bulb then disconnected the line, and tried to start it without the kill switch installed. It started. Then it decided to run itself to about 1500 rpms or so. The boat doesn't have a tach (need help with that, too) so I am just assuming. I started messing with the distributor link and low and behold, I could control the engine RPMs and actually killed the motor messing with it. The distributor (I am assuming is that little plate below the stator and timer base) is always sitting against the bump stop which I am assuming would be WOT. So how do you get the thing to sit at the back of the motor and run with the throttle movement??? Oh, by the way, glad I was at the river checking it out this time....the engine was cool to the touch the whole time, so impeller worries are out the door now. LOL!!!