Oooops I forgot!!!

[julesstar]

Hi, Sorry to sound so STUPID but... I just bought my first boat Today I replaced my trigger, stator and rectifier. I removed the flywheel and forgot to mark. I DO have a mark on the flywheel cover and a bunch of numbers on a decal on the flywheel itself. I am new to the whole engine repair thing and would sure appreciate any help here...My engine is a 1979 mercury 150 V6. I DO NOT want to put the flywheel back on until I know exactly where it should be pointing. My wife is gonna kill me If I spend anymore $$$ on this thing this week!!! LOL anyway if ANYONE can help it would be great!! I do not have but am going to buy a Mercury manual for my motor. Thank you in advance for any help ANYONE can give me. I REALLY WANTED TO GO FISIN IN THE MORNING!

 

[Barnacle_Bill]

Re: Oooops I forgot!!!

It fits over a woodruf key so it can only go on one way. Be sure to torque the large nut down to 100 ft lbs.

 

[julesstar]

Re: Oooops I forgot!!!

Thank you so much for your reply!!! What is a woodruf Key? And I don't understand...There are MANY grooves on the shaft where the nut goes on there are 8 bolts in the center also. I don't mean to sound like an idiot but it seems like it can go on any one of the grooves??

 

[Sig_Mech]

Re: Oooops I forgot!!!

Hey jules, let me get this straight, instead of just taking off the nut and pulling the flywheel from the shaft, you also took off all 8 bolts from the top of the flywheel and removed the plate with the timing mark on it. OK, try this, the plate you removed should have 4 holes in it, 2 on opposite sides of the plate. Look closely at the top of the flywheel and see if you can spot where these 4 holes would line up (it would show as 4 little discolored circles on the flywheel). This will at least narrow it down to a 50/50 chance of getting it right. Bolt it all back together, slip it on the shaft, pull your plugs and turn it by hand until the #1 cylinder is at TDC (top dead center). If the marks are close then you're good. If not, your 180 out.

 

[julesstar]

Re: Oooops I forgot!!!

Thanks for the reply Sig Mec. I did find the woodruf key on the shaft and also the center piece that bolts on to the flywheel. I had to unbolt the 8 bolts off the center of the flywheel where it conects to the part that gets bolted onto the shaft in order to use a Puller because the center piece was froze onto the shaft. I DID NOT however unbolt the 8 bolts on the outside of the flywheel....Is this making any sense??? so really the only bolts that where removed from the flywheel are the 8 center ones....So Iguess what I need to know is where the decal with the timing number decal goes in referance to the woodruff key on the shaft. Any help would be GREATLY APPRECIATED I took tommorrow off just to go fishing early, And with only 3 hours left it just might not happen! PLEASE HELP IF ANYONE CAN.

 

[Barnacle_Bill]

Re: Oooops I forgot!!!

Manually turn the motor over until #1 cyl (top starboard) is at the top of it's stroke. Now install the flywheel so the timing pointer is pointing to approximately 8? ATDC. (it may not be exact) Now you should do a link & sync according to your manual. This will verify everything is set right.

 

[julesstar]

Re: Oooops I forgot!!! 1979 Mecury 150HP Serial #5160146

Re: Oooops I forgot!!! 1979 Mecury 150HP Serial #5160146

Thanks So much for your Replies!!! I just have 2 Questions...1. Is the top of it's stroke when the piston is out towards the spark plug?...2 Is ATDC to the right or left of the center?? on my engine there is a decal on the flywheel and a permanent metal marking that is on a plastic cover that goes over the flywheel. AND ALSO>>>Does my motor turn clockwise or counter clockwise when it runs? Sorry to sound stupid but I just want to get it right. Everyone on this site is AWESOME!! It's nice to know there are people helping others out on here.

 

[saumon]

Re: Oooops I forgot!!! 1979 Mecury 150HP Serial #5160146

Re: Oooops I forgot!!! 1979 Mecury 150HP Serial #5160146

Thanks So much for your Replies!!! I just have 2 Questions...1. Is the top of it's stroke when the piston is out towards the spark plug?...2 Is ATDC to the right or left of the center?? on my engine there is a decal on the flywheel and a permanent metal marking that is on a plastic cover that goes over the flywheel. AND ALSO>>>Does my motor turn clockwise or counter clockwise when it runs? Sorry to sound stupid but I just want to get it right. Everyone on this site is AWESOME!! It's nice to know there are people helping others out on here.

1: yes
2: right
3: clockwise

Note: ATDC mean "after top dead center", so as it turn clockwise viewed from over the flywheel, ATDC is at the right of the center...

 

[emckelvy]

Re: Oooops I forgot!!!

TDC is when the piston is at the top of its compression stroke, i.e. closest to the spark plug.

All Mercs (and outboards in general except for Direct Reversing Mercs) rotate clockwise when viewed from the top of the engine. DR Mercs still rotate clockwise for Fwd gear, but actually start and run CCW for reverse! How's THAT for a mind-bender!!?

The guys are correct in saying that when #1 piston is a TDC, there's only one way the flywheel can bolt back up and have the timing decal correctly positioned. With #1 at TDC, none of the other positions will even come close to lining up.

And if you were to position the flywheel such that the decal is lined up at Zero with the stationary timing mark, the numbers to the Left would be BTDC, and the numbers to the right would be ATDC. You'll notice there are probably more #'s to the left since that's the part of the timing scale you'll be working with when you adjust maximum spark advance.

BTW you should use a drop of red Loctite on each one of those bolts and torque to SAE specs for fine-threaded Grade 8 bolts. I'm assuming yours are 5/16"-NF so you'd torque to approx 25 ft-lbs.

Note if you don't have a good manual, that should be your next expenditure; invaluable for the D-I-Y boat mechanic.

HTH...........ed

 

[julesstar]

Re: Oooops I forgot!!!

Thanks Soooo much guys! So it would be correct that I should move the #1 cyln all the way out (towards the plug) and set the marker at 8 degrees ATDC?? Then just Start the motor? Do I have to set Any thing else?? Thanks again for all your help AND...YES I will buy a Manual Monday Morning!!

 

[julesstar]

Re: Oooops I forgot!!! PLEASE HELP!!! ANYONE!!!

Re: Oooops I forgot!!! PLEASE HELP!!! ANYONE!!!

OK....I turned motor by hand until #1 cyln was all the way out....Set at 8 ATDC and NOW the motor won't even start!!! The motor At least started prior to replacing the NEW Stator, Trigger, Rectifier....What can I do Now??? I think the timing is off but I do not know where to set it to??? I have NO IDEA where it's supposed to be to start??? Please Help!!!! I can not afford to take it to a shop right now. I appreciate ANYONES help with this.

 

[Barnacle_Bill]

Re: Oooops I forgot!!!

Are you getting spark? Even with the flywheel installed wrong you would still get spark, just at the wrong time.

 

[julesstar]

Re: Oooops I forgot!!!

How can I test if I am getting spark? I went and got a new ADVANCE timing light...Is there a way that I can tell?? Please help!!! I am getting Soooo frustrated

 

[Barnacle_Bill]

Re: Oooops I forgot!!!

How can I test if I am getting spark? I went and got a new ADVANCE timing light...Is there a way that I can tell?? Please help!!! I am getting Soooo frustrated

That will tell you. Check all plugs.