85 force timing way off

[Pallindrome]

First off I'd like to say thanks, this forum has been a wealth of knowledge, with very little to no misinformation. I bought a boat a few weeks ago with a 1985 85hp force outboard that did not start. I dont know what was done to the boat prior to me owning it, guy was exceptionally unknowledgeable.

I've done everything one would do to diagnose a no start, I have a nice spark, gas and air in the cylinders, and compression is top to bottom 121 115 120. Found more than a few little things that have made me realize this guy had tried to fix it at one point, mixed up wires going to cdi, improperly installed float bowls etc. Ive run through everyrhing and to my knowledge it is all sorted out. I have the clymer manual and i have rebuilt more than a few snowmobiles. Not a pro mechanic but I know my way around. Still no bang.

started suspecting timing. Found TDC of all 3 cylinders and marked clearly on flywheel. Here's the first hiccup. The 2 lines etched in the wheel should be lining up relatively closely with the first cylinder. Not the case. They line up with the third. Ok no big deal I think, I roll on with the tests. My timing is about 60 degrees retarded. Ok, pull the wheel. Well the key is in two pieces, sheared right in half. Inspection of the shaft and wheel indicate it spun around a few times with pieces of key attached and is nowhere near where it should be.

now I dont have a key floating around so I get one on order. Me and my buddy head to the garage and find a piece of flat bar that fits snugly in the groove, file it down and have a pretty decent home made key. Plug it in, re install flywheel. Hook up timing light. Cylinders tdc and spark are lining up just like they did before, bottom cylinder being the etched markings on the flywheel and the other two falling on their respective Marks. Here is where I lose my mind. My timing is retarded 30 degrees, with my timing adjust screw adjusted as advanced as possible.

the only thing I can think of is this guy swapped flywheels at some point with one that does not match the year or hp or cylinder count. I cant imagine how else a flywheel with a key can be so far off. I have double checked to make sure the key stayed in place during install and it has. I have a new flywheel ordered but I wanted to get some opinions of people more experienced than me on other possible causes or solutions. And maybe this can help someone else out at some point. I can post any info or pictures you may need.

 

[jerryjerry05]

Are you advancing the throttle all the way forward when doing the tests?
Look/read the first posts in the Force forum.
It explains the "static timing" procedures.

You can do more damage with a homemade key.
You can make the slots bigger when it slops around.

Usually the timing doesn't move unless someone has messed with it.
Changing the trigger would be the only time it should be adjusted.

Yu need to ground the plug leads when testing or you can blow a pack.

 

[Pallindrome]

Following static timing test procedure to a T. Grounded coils, WOT etc. And I'm 30 degrees retarded still. I'm having a hard time comprehending why it could be so far off, even if the key wasn't 100% perfect. It fits incredibly snugly into both slots. I wouldn't run it with that key, but for timing tests it shouldn't hurt.
Any other thoughts?

 

[Jiggz]

Contrary to popular belief, the key is more of a reference point rather than a holding point. The shaft is tapered and it is the flywheel nut tightness that holds the flywheel in place. Anyways, double check the trigger coil is installed correctly (although it is really very hard to install it any other way) and with the trigger coil plate free to move. Check #1 cylinder TDC should align with the flywheel mark. This is the lone marking on the flywheel indicating #1 TDC. The other three marks to the left of this lone marking are the 28, 30, 32 degree BTDC markings.

Top of the timing tower is the timing rod adjustment. There is a rod that connects the tower to the trigger coil plate. When extended, it advances timing. When retracted, retards the timing. Make sure the trigger coil plate is still attached to this rod and is actually moving.

There is an idle screw at the bottom of the timing tower, make sure it is installed and is pushing against the engine block (with idle set) and the cam follower notch is just barely below the eccentric roller. Both are critical in the sense that if the trigger coil plate is seized, any advance in the timing rod pushes the tower back instead of the trigger coil plate going forward.

 

[Pallindrome]

Unfortunately the timing mark on flywheel aligns with cylinder #3 not cylinder #1 TDC. This is my first clue in thinking I have the wrong flywheel attached to the damn thing.

timing plate moves freely and is in sync with throttle. Adjustments can be made via the screw linkeage between timing plate and throttle but it's around 10 or 20 degrees not the 30 or more I need.

is it possible that when the key sheared it caused some pieces in the flywheel to torque, spin, and come out of alignment? It looks like a solid piece but if the center ring of magnets spun could that cause these issues?

again thanks for everyone reading and responding I really appreciate it.

 

[Jiggz]

Based on the year and HP, the flywheel part number is FA615097, which is also used on other Force motors from 83-86 with 85~125 HP. If you search for a pic you an at least compare the pics to your flywheel to see if you have the right one. The most critical parts are the orientation of the magnets in relation to the keyway. Goodluck.

 

[Pallindrome]

Thanks I really hope the new flywheel solves the problem, the new one I have ordered matches the part # exactly should be here Friday, I'll update as soon as I can

 

[jerryjerry05]

Pics of the old flywheel, the marks and the underside.

The "key" holds the flywheel in a certain place if it didn't the timing would be all over.
The smaller magnets in the center allow the pulses to go through the trigger.

 

[Pallindrome]

Cant figure out how to upload, under my profile I started an idea book that has pics of flywheel. It looks identical to the one I ordered

 

[Jiggz]

What about the trigger coil? Does it look original? What are the wire colors? There should be 6 wires or 3 pairs of wires. Is it wired correctly based on original wiring diagram?

 

[Jiggz]

Cant figure out how to upload, under my profile I started an idea book that has pics of flywheel. It looks identical to the one I ordered

Click on the camera icon and it will ask for your files. Make sure it's in jpg format and no greater than 1Mb in size.

 

[jerryjerry05]

The 30d out?? It's possible the last one to touch it hooked the coil wires up wrong?
The leads from the 2 top coils got swapped?

 

[Pallindrome]

The boat fired up and ran in a tub this morning!!!

new flywheel installed, first mark lines up with first cylinder TDC, had to change ignition wires as it was firing wrong, which was a good sign since with the old flywheel stuff just wasn't lined up. Static timing at WOT is 35 degrees advanced which I am hoping will be down at 32degrees of advance with the boat in the water and running. Going out tomorrow I'll post any updates

thanks to all who replied and for everyone who has contributed to the many posts on iboats I've used as help/reference

 

[Jiggz]

I wonder if you can post a pic of the old flywheel from both sides and if possible with the new one too. Just wondering where the difference is between the two, if any. Anyways, congrats and enjoy.

 

[Pallindrome]

This is the interior of the original flywheel, the only difference i can see between the 2 is the gap that each of the magnets has is oriented at the top of this photo. On the "new" flywheel that gap is oriented at where would be the bottom of the ring in this photo. Right next to the slot that I am assuming acts as a trigger to the trigger plate. Maybe these magnets were jolted into their new position whenthe key sheared and it messed up the way it interacts with the trigger plate?

 

[Pallindrome]

Next time I have the flywheel off I'll do a side by side

 

[jerryjerry05]

You wrote:

, had to change ignition wires as it was firing wrong, which was a good sign since with the old flywheel stuff just wasn't lined up.

What did you change?
You sure it wasn't wired wrong and that was the problem?​

 

[Pallindrome]

With the old flywheel I was 30 degrees retarded, switching ignition wires gave me the same degree of retard just on a different cylinder. Took her out for a couple hours and she ran like a top, timing is spot on. Thanks everyone!