Outboard Top Dead Center: Piston Stop Method

[@kevinwhite9937]

You. Da. Man!

[@brooster87]

Thank you Son. I followed your details and my 1984 Mercury Blackmax is running. So excited. The Tdc stop you told me about worked great. Just need to fine tune the timing. Thank you so much.

[@MerCSonL6]

You're welcome my friend. Son

[@geraldoakley7688]

That is a very good video it explains it all in great detail, you are a very patient man, thanks for all your video they help a lot, is there follow up video with the engine running

[@jamesshephard4332]

@MerCSon L6 .. Thanks for being here! Having major challenge finding TDC .. sticker on Flywheel def not accurate ... stranded in Key West :(

[@MerCSonL6]

You'll get Shep Son L6!!!

[@jzjosephzonana3422]

Thanks for your videos very helpful I have the same engine tired to time it so far found tdc but I can’t get it timed I adjust the idle stop screw basically all the way out and I still could not hit between recommend 0 to3 so I had to fully back out throttle screw all the way now it hits around 2 and runs great but my top spark can only hit around 17 20 can’t tell exactly definitely not 28 engine runs it’s restarted but it runs throttle engages very late because it’s not engaging until I hit max spark not sure if anything makes sense but if it does maybe you can point me in the right direction

[@dennisenglish6150]

Video was awesome as usual but where do I find a piston stop ?

[@MerCSonL6]

amzn.to/44i7dAg

[@JohnWisconsin]

One of the most clear instructions! I've been trying to think about what the book says re: the (usually) 0.462"mark on the flywheel? Your explanation of finding TDC was great. I've been taking the word of the existing marking and did the rest of the process but I might go back and verify. My top end is great, idle has been hard to get it low enough but runs just a bit rough in the low RPMs. Any first thought on which way to screw the idle timing? Mine was 11* and when I rechecked, running on the muffs, it went to 12*. For that one, I might try doing it on the lake, in gear. Just looking for a bit of smoothing it out, down low. Thanks again

[@JohnWisconsin]

In other words..screw pickup screw out= closer to TDC or farther ATDC? How might that affect the low end smoothness?

[@MerCSonL6]

It depends on yout L6 my friend. Son

[@craiganderson563]

Hey where can I get one of the piston stops. Thanks for all your videos great help on my motor

[@MerCSonL6]

Amazon or ebay. Look up piston stop tool. Son

[@brooster87]

Hey Son. You had told me about a piston stop that is spring loaded. I got that and found the top dead center but my question is with the spring type Tdc stop, do I use the max limit on the stop or do I find the max limit and then adjust the piston back a little? I’m concerned that with the spring type tdc that I have the piston going to close to the top of the cylinder before the spark fires. Will I burn the piston if it travels too far up the cylinder? I hope they makes sense? I’ll try to clarify if you need me to. Thank you for your help.

[@MerCSonL6]

There should be no spring on your piston stop.

[@raymondchavez1530]

Thank you for this. After finding Tdc, none of the timing marks line up on distributor and belt. Prior to me the flywheel was replaced. Is there a way to fix this? I feel this is why motor won’t start.

[@MerCSonL6]

What do you mean the distributor doesn't line up?

[@robedmiston4389]

Thanks for all your videos, this one in particular because the decal on my flywheel wore off. ‘65 Merc900. My question for you is I have an adjustable piston stop, how long do I make it so the piston doesn’t stop short? Thanks

[@MerCSonL6]

About 1-2 inches. Be careful not to ram the piston into the stop. Son

[@robedmiston4389]

@@MerCSonL6 Thanks, I have TDC now but no degree decal so how can I determine where to set it to begin linknsync?

[@MerCSonL6]

@@robedmiston4389 I use painters tape blue to set the TDC without a pointer. Son

[@gregmielnik5105]

Awesome, will this work if I dismantled the flywheel, I unbolted it ring that has the key way form the crankshaft and of course it moved, help help help

[@MerCSonL6]

Flywheel needs to be in position to find TDC. Son

[@colsmith7257]

Tricks of trade, I have to say your Mrs must really love you to allow allow all your l6s over her back balcony.

[@TheStone1965]

Hi Mrs MerCSon just I want to ask you please if don’t mind about the butter fly in front of the carburettor important to start the engine or not because I don’t have it in my engine and I have to put my hand to close the carburettor to start the engine and when it start it will start again with out my hand in half turn but after 2 hours it wants start and I called 2 specialist mechanic and buth said you have to butterflies.so what you think?and if I have to can you help me to buy it because we don’t have it in our country and I can’t find it online please. Thanks

[@MerCSonL6]

They are used to choke the engine. You can bypass that system by pumping fuel directly into your crank. I have a video on this procedure.

[@MerCSonL6]

kzbin.info/www/bejne/gmOoap5ri7yXsKs

[@TheStone1965]

Hi my friend thanks for the replying and did pump fuel in top of the crankshaft and it was Wark perfect thanks again for everything

[@maryfithen5006]

What brand / model is your piston stop. Can’t seam to fond one on e-bay that is for mercury outboard

[@MerCSonL6]

Stens 700-815 Piston Stop, Silver a.co/d/eNbPijj

[@mrcamaro615]

Just wondering what state or area you live in? I have a 1980 115 L6 with ADI ignition that I have been having some issues with

[@MerCSonL6]

25401. Son

[@matthewbrock4289]

I bought 1985 bass tracker it has 1981 115 mercury L6, compression is 121 in all cylinders, is that good or bad

[@MerCSonL6]

That's mid life.

[@semaj2358]

I have a mercury inline 6 115hp someone took the 8 bolts that's on top of my flywheel off I replaced them all with oem parts and my flywheel isnt lining up my questions to you is what is the torque for those 8 bolts or do I just use threadlock blue on it? also do I find the TDC with the piston stop method and take my flywheel off and line it up with the three dots or I disregard the flywheel sticker hope you understand my question been trying to figure this out for a week

[@MerCSonL6]

Does your engine have 3 dots and a sticker? I would line it up with the TDC on your sticker then tighten the flywheel screws. Can't remember the exact torque but just make sure all are tight using a criss cross pattern. Son

[@Depsay5566]

If you take the fly wheel plate off, and don’t put it back at the same spot, then you’d need to refine tdc and those dots are not accurate right?

[@clarencjretap3685]

Hello sir and thanks for the video, I found tdc and I have a 1972 - 80 hp merc. The timing calls for 23 degrees BTDC, and how do I do this? Plus, do I need to align the rotor to the points in the distributor, or just leave it. Thank you

[@clarencjretap3685]

Align the rotor to the #1 in the distributor at tdc, because when I align everything, the rotor is between the 1-3, thanks

[@petersheamorris4852]

Is that method the same for Johnson Evinrude 25 horse 77

[@MerCSonL6]

It's similar but different. Son

[@Depsay5566]

So I have the same one pictured here minus mine has the 3 dots and everything in it is abit dry rot. She runs good but I’m trying to adjust the timing. Where do you get parts for these old machines?

[@Depsay5566]

Could I find tdc with the keyway on the flywheel to align my distributor up? Or is it solely this method?

[@MerCSonL6]

I would use this method. Marineengine.com is a great place to start. Son

[@LuisSanchez-nv9nk]

Question so after doing all the procedure what if the time pointer is to far out to mark TDC? I have a 1997 ocean runner and the time pointer only gives you so little movement.

[@MerCSonL6]

You will have to define your TDC without the pointer. I had an L3 at one point I have to time from the back of the engine due some uncharacteristic alignment. Ran great. Hopefully this helps. Son

[@jasestieglitz9761]

How would you do it on a 77 1500 Mercury ?

[@MerCSonL6]

Absolutely. Son

[@duckco1]

Will this method work on a newer Merc like a 2000 model?

[@MerCSonL6]

Yes, however, the 2000 models have a flat piston head. Son

[@joshm9261]

Hi do u have a part number of link to get the piston stop

[@MerCSonL6]

www.ebay.com/itm/131766373788

[@vinhoi69]

I am so confuse. I have a 1989 70 hp johnson that has been rebuilt so I need to adjust the timing. I did exactly the way he show on the video but it come back to the same point.

[@MerCSonL6]

I'm not sure I understand the question. Son

[@vinhoi69]

@@MerCSonL6 could you please show me the way to check the TDC of johnson 70 hp 1989.

[@MerCSonL6]

@@vinhoi69 Johnson or mercury.... the principles are the same. The video explains in detail how to achieve this. At TDC your #1 piston will be visible through the number #1 piston spark plug hole. Son

[@vinhoi69]

@@MerCSonL6 I did exactly as you showed on video, but it came back to the same point.

[@MerCSonL6]

@@vinhoi69 same point meaning what?

[@joemorales3906]

Very helpful I had a couple questions about an older 82 50hp merc that I have please message back thanks in advance

[@MerCSonL6]

What are your questions? Son

[@joemorales3906]

Is my 82 50 hp mercury motor considered a L6 motor?

[@MerCSonL6]

@@joemorales3906 L4. Inline 4. Son

[@joemorales3906]

@@MerCSonL6 I just changed the switch box last night and getting ready to try it out this morning

[@KP_Nation]

I have a 79 merc 900. I've used the screwdriver method, but I'm not satisfied. What size piston stop do I need?

[@MerCSonL6]

14mm. This is what I use: www.ebay.com/itm/131766373788

[@KP_Nation]

thanks so much

[@elijahmcdonald6552]

I have a 75 hp 1984 i would like to talk to you

[@vinhoi69]

Please Help. I have an 1989 Johnson 70HP rebuild by Coastline Marine in Florida. The rebuild cost $3180. (rebuild include: bore the 2 bottom cylinders to the next larger size piston. replace the top piston for cylinder 1, rebuild carbs, new thermostat). The guy told me to check the ignition and timing by a mechanic. I have called every marina in Boston area to have them check the timing for me but no one is willing to work on older motor so I have to check the ignition/timing myself. I have watched KZbin videos bought 2 manuals to do the timing/ignition myself. When I check the TDC of the motor, new TDC mark that I've found is 2.5" to the left of the factory TDC. Is this correct ? TDC needs to be correct before I can continue forward. Thanks for your help.