Mercury 7.5hp and 9.8hp 2-Stroke Twins, Fixing Old Ignitions & Setting Points

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5 жыл бұрын

Have my winter projects, picking over the pile and deciding which to fix and which to use for parts....have a couple of "common" issues across these Mercury Outboard Project motors. The wiring from the ignition to the Coils has degraded to the point the wires need replacement.

Пікірлер: 84

@jfservices4944 4 жыл бұрын

I've seen two of these small capacity Mercury motors with completely shot wiring insulation. The wires look ok visually but crumble to dust when you squeeze them. Both had poor starting/running issues. There was a spark but it was not strong enough when under load. Rewired both, very easy job, cleaned and re-gapped points, both start first pull hot or cold. They are amazing quality engineering from the good ol' days. Great video

@sammyrothrock6981 2 жыл бұрын

Absolutely I have one I replaced most of the wiring with teflon coated

@JAKimmet 3 жыл бұрын

came here for the 9.8 wiring issues I'm having realized early not going to be the same y 9.8 is 19882. had to stick around to catch a glimpse of the aircooled KTM with massive cooling fins. glad I did, I want to make one of those spark checker tools.

@ct1762 2 жыл бұрын

those thunderbolt ignitions were quite advanced for their day. the red module... as far as i can tell... has a transistor in it that acts like an amplifier. things put out some crazy voltage!

@Wood.Water.Camping 5 жыл бұрын

Looks like you are going to be busy this winter. Great video as always

@MichaelTaranto88 5 жыл бұрын

That vor is bad ass! Havent seen one in years

@massimilianogiannone8417 2 жыл бұрын

Hi, I bought the exact same engine and I am very happy with it. Since I have to replace the propeller, could you give me the right measurements: pitch and diameter? Thank you very much

@augustoduminuco4683 3 жыл бұрын

I would love to know where I can buy the new ignition system you used?

@peterfaggella3120 4 жыл бұрын

Hey! you didnt' happen to know the diameter of the carb opening at the front intake cover did you? I have a Merc here with no decals, the serial number crosses to both a 7.5 and 9.8. the only thing I can come up with is the diameter of the carb opening or the jet and I don't have a way of measuring the jet.

@Orr_s 3 жыл бұрын

And you can use J plugs on these?? I always thought and have read everywhere that these older mercury motors always need to use a surface gap/ gapless plug to avoid damage to motor. Specifically champion or AC delco but we have ran NGK in ours and it just recently fouled the plugs. I also read there is no fuel/air mix and it is in fact a adjustment for the timing, not the carb air/fuel

@Dubence 4 жыл бұрын

Hey, great video! So I’m having issue with a 1970 7.5 Mercury where water is not flowing properly out of the Pee hole, it’s more of just a spitting, And the water that does come out gets pretty hot. Already changed the impeller, pulled the water case off (i think it’s what it’s called, it’s the plate around the spark plugs) inspected the gasket no issues, then pulled the exhaust case off inspected the gasket no issues, water flows up to the exhaust case but still is spitting. My next step is the power head but i have a question, will the water coming up from the lower unit is it supposed to flow constantly or just spit?

@afleetcommand 4 жыл бұрын

I would look at the rubber grommets/gasket from the water pump housing to the water tube & under the motor from tube to the motor. I have seen pieces of impeller block the water flow. Also the water tube mash in the rubber seals vs. slide in as they are supposed to. Also it's worth checking that impeller and the seals at the top of the water pump housing. I've seen folk replace the impeller and not those seals and the water is squeezed out the seals vs up to the motor. But if the water is spitting out warm to hot.....it's not getting enough.

@sammyrothrock6981 2 жыл бұрын

Pull lower check impeller

@johntobin4037 5 жыл бұрын

Hi there Any idea what the gap should be on a husqvarna 65 L which also has points I am rebuilding a saw from the crank up it was seized when I got it and am not sure how to set the ignition now that I have removed it I should say greetings from Ireland and that I am a big fan of your chainsaw vids particularly the builds Thanks John

@rdh2059 4 жыл бұрын

What does this have to do with outboards?

@davidaltizer5859 4 жыл бұрын

Hey where did y’all get the points at I can’t find any for mine. My serial number is 3737124 and it’s a 110 9.8hp

@adamschloegel1790 4 жыл бұрын

Where did you get your aftermarket coils? I just picked up the same motor and the coils need replaced

@afleetcommand 4 жыл бұрын

eBay

@britneyreynolds4147 5 жыл бұрын

Is the carburetor on the 9.8 a KB11-a? I can’t figure out which carb I need.

@afleetcommand 5 жыл бұрын

On that series there are a few carb / fuel pump combinations from the external fuel pump as mine have to one integral to the carb on the later ones.. SO really the best approach is to start with the serial number ( on the mid section right at the top ) and go to a place such as this too find out: www.marineengine.com/parts/mercury-outboard-parts/

@LetsFigureThisOut 5 жыл бұрын

I have a similar engine and can't find the points. any suggestions for vendors?

@afleetcommand 5 жыл бұрын

Did you try www.marineengine.com/parts/sierra-marine/sierra-marine-parts-catalog-00345.htm

@Orr_s 3 жыл бұрын

Do you know what year that 7.5 hp was?

@user-jk9dl6ct2s Жыл бұрын

Where did you find those coil packs ? I can only find the black ones that don’t have the 3 screw holes like the red ones do that I need

@afleetcommand Жыл бұрын

Some I got from "Marineengine.com" and others simply off eBay. The Marineengine website is an awesome reference as well. SINCE they have that, I often buy from there regardless of price to support them.

@bretttonin7236 Жыл бұрын

What gauge or voltage of wiring can I use to splice the ignition coils. I have a 1973 merc 110 9.8 and the wiring is extremely frayed in one wire. Thanks in advanced !

@thejunkninja3028 4 ай бұрын

Hi, i have the same question, same engine 1973 Mercury 9.8 with rotted cables. Did you ever find out what gauge should they be ?

@samsungs6edge986 4 жыл бұрын

Help!! MY Mercury 9.8hp 110 is running on only one cilinder... somethimes the other cilinder catch in but the lower cilinder is working better then the upper one can somebody help me,

@afleetcommand 4 жыл бұрын

Pretty hard to debug over the internet, if you have mechanical skills, go through the basics! Compression, Spark, fuel supply.....check compression in both cylinders....should be over 100psi and within a few pounds of each other. Check spark & spark plugs for clues...if they are dry suspect fuel supply, if wet ignition or carb issues. stuff like that. If you don't that's why dealers exist. I assume those watching these videos have a mechanical back ground..

@outboardfixer 5 жыл бұрын

What is the serial numbers on those engines? I have one painted ALL BLACK by someone and can't get a number but the same as these....if you could help me THANK YOU!!

@afleetcommand 5 жыл бұрын

I would go to a site such as www.marineengine.com/parts/sierra-marine/sierra-marine-parts-catalog-00345.htm And try to match up parts like ignitions and carbs to "sync" up to get a range

@PROGRESSROBO 4 жыл бұрын

What year motor is this?

@locknload9143 2 жыл бұрын

Hey great videos! Question..Can I remove the flywheel "without" a 3 point puller? Mercury 9.8 1986 2 stroke. only have a 2 point hook puller at the moment. 11pm

@afleetcommand 2 жыл бұрын

theoretically I guess.. Harbor freight is cheaper than damaging unobtainable parts

@locknload9143 2 жыл бұрын

@@afleetcommand ...Thanks for the reply. I just went a purchased another puller. Figured why take any chances.

@locknload9143 2 жыл бұрын

My engine looks exactly the same as the one you're working on except for the carb..Anyways when I cleaned my points, I had my stator removed (rewired it) but, I used a small tiny wrench from a "Toy Meccano set", magnetized it, and a 90° pick for the nut...What a Pain in the A$$ but it worked! lol...13:04 mark what did you oil? Also what was the torque on your flywheel nut?

@afleetcommand 2 жыл бұрын

I'll have to go back into the archives on the torque.

@locknload9143 2 жыл бұрын

@@afleetcommand How exactly did you line up your points? High side lobe to the end that touches the shaft. Thanks!

@RickWilson93 3 жыл бұрын

What gauge wire did you use for the rewiring of the second 7.5?

@afleetcommand 3 жыл бұрын

@RickWilson93 3 жыл бұрын

@@afleetcommand Thanks. I'm rewiring the ignition on a 1972 Mercury 7.5, your video will help!

@gracelutherangreenwood7499 2 жыл бұрын

I just acquired a 1970 7.5hp Mercury. All the wiring (there isn’t much to begin with) is shot, and I can’t find a wiring diagram anywhere (including in the service manual recommended by Mercury customer service). Any chance you could take a video or post pics of the wiring on the 7.5? I need to see where everything goes.

@afleetcommand 2 жыл бұрын

Will try, I actually found a schematic online. At least for wiring the coils and stuff. I think I posted it in one of my video's. On the "HTSS Outboards Boats & Trains" channel. Did a 20hp long shaft task and posted that in there. I'll look and see if I can find that video...was a while back.

@afleetcommand 2 жыл бұрын

Check out around minute 11:30 on this one: kzfaq.info/get/bejne/mcyPqMd4u93deWQ.html

@afleetcommand 2 жыл бұрын

kzfaq.info/get/bejne/ot6GjNKesLzFpnU.html

@ethanmontgomery7915 Жыл бұрын

I've been trying to find the right power pack for a model 75 7.5hp mercury thunderbolt any help might be long shot on comments on here....

@afleetcommand Жыл бұрын

ebay has aftermarket versions. Best way is to go into "marineengine.com" and hunt for both one for a motor with a serial number range encompassing your ad ALSO an ignition pack the looks like yours. Both. THEN get the part number and hunt on eBay.

@danmcginn772 5 жыл бұрын

does the motor have to be turned to TDC before you gap your points?

@afleetcommand 5 жыл бұрын

Not really as there is a fixed cam on the crank shaft that opens the points. really just need to get it to the high spot for each side one at a time, where the points are opened to then set the points. As for timing, when you operate the throttle on those goofy old motors, you are also turning the entire stator plate therefor advancing and retarding the timing. Setting that up is another entire conversation and the reality is you are constrained as the linkage is a fixed system not giving much to work with in setting ignition timing on those.

@danmcginn772 5 жыл бұрын

Ya,i have a 1970 4hp kiekhaefer and it is bullet proof.i also just got a 1984 4.5hp which i got running with ease and can't what to try it this summer.I love these old Merc motors.I hated the johnson n Evinrudes i owned,nothing but a pain in the ass to work on and keep running properly.I was blinded by the johnson hype,until i owned n worked on both.Was just asking cuz i never owned a 7.5hp,thanks!

@shafi420 5 жыл бұрын

So can I take a 7.5hp and enlarge the carb hole and get a 9.9 carb and have a 9.9hp outboard?

@afleetcommand 5 жыл бұрын

Larger carb & intake "hole" in the case...yes Everything else is essentially the same part number for part number. ( to a 9.8, not the 9.9 ) Best way is to disassemble and work on the case half where you can clean off and filings or other residue, But if you choose to try with the thing still together, you better have the skills to do that work without introducing "chips" or metal filings into the case.

@farmerbenny7 11 ай бұрын

You ever get this done? Would buying a 9.8carb do the trick?

@afleetcommand 11 ай бұрын

Did, the block had a smaller hole so I opened it up and put on the bigger carb. Sold it / traded actually for the 20hp merc I have on a fishing boat. Moved most of my boat related activities over to the HTSS Outboards Boats & Trains KZfaq channel.

@thomasnichols1129 3 жыл бұрын

where did you get the new points and what is the part numbers thanks

@afleetcommand 3 жыл бұрын

www.marineengine.com/parts/mercury-outboard-parts/110/1865779-thru-2798056/flywheel-stator-and-ignition-coil

@afleetcommand 3 жыл бұрын

Best get the serial number and go to marineengine.com

@afleetcommand 3 жыл бұрын

I think in the video I did for the 20hp mercs I cover how to navigate thru those sites.

@afleetcommand 3 жыл бұрын

kzfaq.info/get/bejne/oteXgtGg3tG5YH0.html

@chadhall9606 4 ай бұрын

Can you do a video on cdi box replacement what wires go where

@afleetcommand 4 ай бұрын

maybe, actually on my other channel think I did or at least showed a wiring diagram ( HTSS Outboards Boats & Trains )

@chadhall9606 4 ай бұрын

@@afleetcommand ok thanks just gonna wire it up like the old one that's on it I don't think it's bad just wires are all deteriorated

@afleetcommand 4 ай бұрын

There is a wire diagram in either my other channel's 200 video or 110

@garyrichard2177 Жыл бұрын

got what I think is a 1968 mercury 6 hp need points and condenser were can find parts. all so have 1969 9.8 that have same type points and condenser

@afleetcommand Жыл бұрын

ebay , amazon, but the best place usually is marineengine.com . And they also have the parts schematics to where you can get not just the OEM part numbers to work with, but also the aftermarket ones where they may have superseded or replaced NLS OEM parts.

@christiandanielarmenta8483 Жыл бұрын

Nesecito de esos puntos dond los consigos ???

@MoneyThao 5 жыл бұрын

I have afew mercury that dont have spark. Cant find whats wrong with it

@afleetcommand 5 жыл бұрын

Which ignitions? What years, if you have the Serial no's I'll do a little research. I think I did show the fact we got them to spark didn't we in that video? I had to re-engineer the location of those fuel pumps to get them to start easily BTW. Some of the later Mercuries with the CDI they call "switch boxes" sometimes they just...fail. But if its an older points system, should be able to get them to work. And the other little "twist" is if they are an open or closed system....that can get folks confused as most are used to open systems where the kill wire grounds it out and therefore stops the spark, many of those "hybrids" they have were closed systems, problem is even a corroded connection can stop them from creating spark. That one in the video was a closed system....

@seriksson9721 4 жыл бұрын

@@afleetcommand You are really a skilled and knowledgeable person, it is with great pleasure that i look at your programs on both chainsaws and boat engines. Clearly impressive.

@davemall1 3 жыл бұрын

What wire are you using to replace the points wires?

@afleetcommand 3 жыл бұрын

primary wire from NAPA

@davemall1 3 жыл бұрын

@@afleetcommand Would you happen to know what gage it is? I may try to order it online...I am not close to any auto parts stores.

@mstg966 5 жыл бұрын

Are the lower ends the same on the 7.5 and 9.8?

@afleetcommand 5 жыл бұрын

yes

@squareuporfuckyouderkie 5 жыл бұрын

Wesley king do you know if coils from a 7.5 will do on the 9.8

@afleetcommand 5 жыл бұрын

@@squareuporfuckyouderkie IF the the ignition is of the same type they interchange. There are a couple of different ignition's that were on that series of motor. Use the website to check your serial number, then go over and look at the 110's and 9.8's and you will see they even use the same pictures. www.marineengine.com/parts/mercury-outboard-parts/

@MoneyThao 5 жыл бұрын

Dose it run... didnt see you start it....

@afleetcommand 5 жыл бұрын

Runs good, that time the water test tank was sill out side & weather is typical of here that entire week.. It will show up in future video's both those two both will. At the time I posted didn't move the fuel pump yet, its now like the older ones and they both are running. Wasn't going to fire it up with the water pump impeller dry anyway..:) Some video already collected, and Its headed to North Carolina and a video to tweak & tune is in process.

@brandonprettyman269 4 жыл бұрын

Hey were are you guy's located