Timing marks wayyyy off 200 hp mariner

RMSBuffalo

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I'm trying to time this motor but following both the Seloc and Clymer manuals, they say to turn the flywheel to drive the piston .042 off TDC. Then supposedly the timing indicator should line up with the .042 mark on the flywheel. Problem is it's so far off, I can't move the indicator even close to the mark.
The motor's running rough ("chugging"), but there's no carb adjustment for fuel mixture. What I've done so far = Compression check 110 to 117 PSI. New plugs, replaced 1 coil (plug wasn't sparking), Tore down 3 dual carbs and cleaned and replaced gaskets & seals. It seemed that all that was left was to time/syncronize but the marks aren't right. Any suggestions?
 

achris

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Re: Timing marks wayyyy off 200 hp mariner

Firstly, use the cylmer and seloc manual for toilet paper and get the Merc genuine manual. Secondly the correct depth for the piston for checking the timing mark adjustment is 0.462", not 42 thou... Get the right manual....

Chris............
 

RMSBuffalo

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Re: Timing marks wayyyy off 200 hp mariner

My mistake, the manuals did say .462, I didn't have the books with me when I posted and was speaking "off the cuff". Doesn't change the problem though, it's the .462 mark I can't line up with. I agree the manuals suck and they pretty much copy each other almost word for word. So the situation is this:
I'll have to research where to get the Merc manual, and no doubt by the time I get it the fishing season is pretty much going to be over for me. Any solution to the problem I posed?
 

achris

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Re: Timing marks wayyyy off 200 hp mariner

What's your engine serial number and I'll post up the right info....

Chris...........
 

achris

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Re: Timing marks wayyyy off 200 hp mariner

sorry, double post:(
 

j_martin

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Re: Timing marks wayyyy off 200 hp mariner

The 16 amp flywheel can be disassembled and then put back out of clock. If that's what's happened, you need to take out the ring of bolts on top of the flywheel, line up the marks, and reinstall it. The splined hub is keyed and only goes on the crank in one position.

hope it helps
John
 

RMSBuffalo

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Re: Timing marks wayyyy off 200 hp mariner

Thanks for getting back to me guys. Sorry it took a while for me to view but I was out of town a couple of days.
The serial # is OB232180 I believe this is around a 1989 model year but I don't know for sure. The serial # doesn't seem to match up to all web sites and doesn't really match out with the manuals although I haven't had any problems getting parts.

The flywheel being off clock...hmmmm....that is what I suspected but I didn't know for sure if it could just be put back on differently. From your post John, I'm reading that the hub is splined but the flywheel can be changed on the hub. If this is the case I can just remove the flywheel without having to mess around with any splines, and just slide it over a bolt or two so that the timing mark is at least in the right neighborhood. Once it's close I can fine tune it and then run the timing light. Sounds good, I'll try it now and keep you posted.

Thanks again,

Jerry
 

achris

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Re: Timing marks wayyyy off 200 hp mariner

It's 1987... and here's the procedure for setting up the timing pointer...

V6timing.jpg
 

RMSBuffalo

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Re: Timing marks wayyyy off 200 hp mariner

Thanks for the info Chris, however those are the exact instructions I've followed using the TP manuals. Problem is the timing mark on the flywheel doesn't even enter the field of the timing pointer adjustment. I did follow the advice of another poster, (J_Martin) and moved the flywheel over by one bolt hole. That took the timing mark to the other side of the timing pointer though, so I still can't calibrate to it. The only things that I can think of are that my dial indicator is lying to me or I reading it wrong (though I can't imagine how), or I'm measuring the wrong cylinder. The books say Cylinder #1 which is top cylinder, starboard side, right?

Interesting observation from your last reply though...
You posted info for Serial#6073192 and above. Does that mean that my Serial #OB232180 is above #6073192? Nothing that I've read anywhere references the letters in the serial # so I've kind of ignored them. If my motor is in fact above 6073192 then I've probably been reading some of the wrong info for my motor which would explain why some instructions don't seem to fit. Unfortunately it doesn't change the timing mark calibration because it looks the same for all of the motors.

Thanks again,

Jerry
 

achris

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Re: Timing marks wayyyy off 200 hp mariner

Jerry,

Yes, the lettered serial numbers are later than (above) the 7 digit numbers...

Silly question... you are turning the engine the right way when trying to set to the 0.464" marks?

Just a thought....
 

RMSBuffalo

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Re: Timing marks wayyyy off 200 hp mariner

Chris,

Wow, you must be on the forum right now!
I've second guessed the rotation a dozen or more times and really can't see that I would be turning it the wrong way, but to verify, when the manuals reference turning it "clockwise", they mean clockwise when looking down at the flywheel right? (They wouldn't be talking about prop rotation would they?)

When I put my dial indicator in the cylinder(I think it's probably a pretty crappy dial indiicator but its the only one I've got), I'm spinning the flywheel and the needle does a few revolutions until it reaches TDC where it maxes out and starts going down. I'm setting that point as zero. Then, I'm backing off from zero until the needle goes aprox 1/4 revolution past .462 wait a minute, I think I just figured it out.

Are the manuals talking about using a specific "Mercury" dial indicator? The dial indicator that I'm using measures in a clockwise direction, meaning in a clockwise direction it goes from 10 to 20 to 30 etc. If the mark of .462 is for Before top dead center, then when turning in a counterclockwise direction from TDC, when my gauge reads .462 it is actually .538 Before TDC which would explain the timing mark not even being in the pointer window. This may be an interpretive problem whereby the manuals are referencing what a specific tool reads as opposed to what the actual measurement is. Does that sound right?

Jerry
 

bjperry

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Re: Timing marks wayyyy off 200 hp mariner

Jerry,

You may be onto something with your dial indicator. I too use a cheapy from Harbor Freight. I set mine at zero when I get to TDC then back it off to .462. On mine each rotation of the needle represents a travel of .1 inch so I need to make 4.62 complete rotations in the needle before I'm where I need to be.

Incidentally I purchased a used powerhead for my 78 v-6 150 and ran into the same problem with the timing marks that you are. I just assumed it was because whoever sent me the power head used a flywheel that wasn't made for the motor though it would fit. I solved it by using the flywheel off my old powerhead and haven't looked back. Still, since you've tried correcting the problem by adjusting the flywheel I suspect you're problem is actually that you've been misreading your dial indicator. It took me several times the first time I did it to actually make sure I was on the money; not something you want to mess up that's for sure.

Let me know if you have further questions.

Benjamen
 

j_martin

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Re: Timing marks wayyyy off 200 hp mariner

It's unclear to me what you're doing. Some notes:

1. only rotate the engine clockwise. Going backward can seriously hurt the water pump.

2. .462 is the drop off from top dead center. If your dial indicator doesn't read upward when the shaft is extending, you have to calculate the difference between where you set it, and .462. At .100 per revolution, you would go 4 turns, then down to .038. Most dial indicators have a second needle that indicates the number of turns from relaxed.

Example setup, Zero would be 0 with second needle on 5. .462 then would be the first .038 from contact.

3. Set zero, then turn engine (clockwise, see note 1) most of a revolution till it contacts the depth gauge, the go to your .462 calculated position.

I use a 15 dollar digital caliper. I tie wrap it on an old spark plug frame with a tab welded on it so the depth gauge sticks into the cylinder. I stick it in and inch and rotate the engine one turn to get it to the high point. Then I hit reset, and push it back into the engine. Then I rotate the flywheel till it gets to .462.

hope it helps
John
 

j_martin

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Re: Timing marks wayyyy off 200 hp mariner

In Pictures.
 

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j_martin

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Re: Timing marks wayyyy off 200 hp mariner

Continued
 

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bjperry

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Re: Timing marks wayyyy off 200 hp mariner

J Martin,

Step 3 of the manual in the post above specifically says rotate the flywheel counterclockwise. My Merc Shop Manual says the exact same thing. If this had the potential of damaging the impeller (which I can see how it might) why would the manuals say this? I'm assuming you get a different result if you continue to rotate the flywheel clockwise. While the difference may be slight, when dealing with the timing issues of these engines I think I'd rather risk damaging an impeller than toasting an engine.

Benjamen
 

RMSBuffalo

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Re: Timing marks wayyyy off 200 hp mariner

The reason your not supposed to turn the flywheel counterclockwise is that the blades on the water pump impeller will deflect backwards. If you use the starter to crank the engine then it will damage those blades as they reverse direction. That's why they have you turn it clockwise manually after the counterclockwise, so it resets the impeller. If the gentle change of direction when turning it manually damages the impeller, it probably wasn't any good anyhow. I also questioned this because the TP manuals contradicted themselves by saying never turn it counterclockwise and then the instructions tell you to. There is however a bit of a disclaimer saying that cranking after couterclockwise would damage it but not if you manually spin clockwise first.

Jerry
PS Wow, nice to see all the responses and help!
 

j_martin

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Re: Timing marks wayyyy off 200 hp mariner

J Martin,

Step 3 of the manual in the post above specifically says rotate the flywheel counterclockwise. My Merc Shop Manual says the exact same thing. If this had the potential of damaging the impeller (which I can see how it might) why would the manuals say this? I'm assuming you get a different result if you continue to rotate the flywheel clockwise. While the difference may be slight, when dealing with the timing issues of these engines I think I'd rather risk damaging an impeller than toasting an engine.

Benjamen

If you follow step 3, the last move made is clockwise to indication. You go past the mark, then clockwise to it.
1. If the engine isn't about to throw a rod, it wouldn't make but a thou or so of difference anyway
2. Either way, you are coming up to .462" before top, so there is no difference at all.

I prefer to not rotate an engine backward for any reason. It can do damage to the water pump. Why risk it.

That's my story, and I'm stickin' to it.

Jerry, did I help you figure out the dial indicator thing?
John
 

RMSBuffalo

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Re: Timing marks wayyyy off 200 hp mariner

John,
Yes you have helped as has everyone who has responded to this thread. As it turns out, here is the apparent problem:
The spark plugs on this motor are countersunk pretty deep and that coupled with the length of my dial indicator is only allowing me to get .370 of travel on my dial indicator.Therefore, trying to find .462 BTDC is pretty much the futile effort that I have been going through.

This became apparent after you and others on this thread pointed out that each full revolution on the dial indicator equals .100. Unfortunately this confirms I'm an idiot because I was actually going to TDC on the dial indicator and backing it off to what is actually measuring .346 as I misunderstood and ignored the revolutions and mistook the .046 to be the .46 the manual was specifying.

However, per the manual instructions, they say to zero out the dial indicator and then back it off to .462. This simply doesn't make sense unless the dial indicator is actually reading distance traveled backwards. ????? My dial indicator does not, and that would suggest the manuals are telling me to turn the flywheel counterclockwise a considerable amount.

Now, if I'm interpretting it correctly, the objective is to actually measure the top of the piston to a point that is .462 from TDC. This seems to be what Chris is doing with the caliper/modified spark plug insert contraption that he's using. If this is the case, then I think I can figure out a way to do it even though my dial indicator doesn't protrude far enough into the cylinder. Unfortunately it's dark out now and I won't be able to fuss much until tomorrow, but does that seem right?

Here's the big question of the TP manuals though...Wouldn't it make everything alot easier if they told you the objectives of each operation as opposed to just giving step by step robotic instructions? It sure would help us to understand when something isn't working.

TTFN,
Jerry
 

achris

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Re: Timing marks wayyyy off 200 hp mariner

............

Here's the big question of the TP manuals though...Wouldn't it make everything alot easier if they told you the objectives of each operation as opposed to just giving step by step robotic instructions? It sure would help us to understand when something isn't working.

TTFN,
Jerry

For people who actually have the ability to think, yes.... But remember, these manuals are written for the lowest common denominator.. people who can ONLY follow the numbers on the pictures....

Chris........
 
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