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1971 Merc 80 HP Problem Child

fixitdaily

fixitdaily

Regular Contributor
"Iwouild like to present my pr

"Iwouild like to present my problem child here with the hopes of some advise and direction.I have a 1971 merc 80 hp serial #3192882 when i bought this motor (and Boat) didnt have much knowledge on this expierence.The Motor ran looked half way decent so I bought it.I was going to do a tune up and to my disappointment found out that much of the components on this motor are not orig. nor even supposed to be on here.So thanks to e-bay I purchased a Distributor,Swithbox,Coil,Recitifier,and redid some wiring.Carbs were rebuilt and a new fuel pump rebuild.So here is actually my question it starts good idles good but for some reason it doesnt rev up like it should and has an occasional miss,could be bad gas?Any Ideas Suggestions.Thanks guy's for looking...}"
 
"Does it bog when you open the

"Does it bog when you open the throttle, or does it never make good power?

Jeff"
 
"Check spark plug leads,the sp

"Check spark plug leads,the spring loaded brush in the distributor cap for damage,is the rotor ok?you hope,spark advanced too much?4 or 6 cyl? Pull plug leads to see what cyl it's missing on,Check the timing, may be of a little"
 
"No it doesnt bog done it revs

"No it doesnt bog done it revs but not with that normal umph behind it.Now I did put in Ngk plugs that are supposed to be in it,Before it had autolite plugs which I cant find anywhere.I tried putting them in and no go.I think they where history anyway.And it is a 4cyl.I just got in from trying to start it and have no problems starting.I have checked the brush inside the dis. looks good.I havent adjusted any spark advance yet because I am still in the on the muffs mode.And by the way thanks for the responses"
 
I have another small question

I have another small question concerning my serial number.3192883 1972 was the starting numbers 318xxxx I am wondering if this motor and serial number are two different things.Will the engine block tell what year?
 
"I have another small question

"I have another small question concerning my serial number.3192883 1972 was the starting numbers 318xxxx I am wondering if this motor and serial number are two different things.Will the engine block tell what year?I am also alittle confused on the timing setting.Here's what I did,I put Nr.1 cyl.@ TDC. and made sure the 3 dots on the side of the fly wheel and the distributor were lined up.And here is where I get lost.Once I put the top cover back on the the 3 dots on the flywheel show I think 8 degree's TDC.Now I amsupposed to find .464 before TDC with a dial indicator which I have.It says somwhere I need to put a pointer somewhere to set the timing.To be honest I have no Idea what pointer let alone where to put it.I did put a mark on the flywheel in reference to the markings on the cover that shows TDC all the way up to 50 degee's before TDC.So needless to say I havent adjusted anything major concerning timing.Idle set screws are 1 1/4 turns out and it runs-idles.Just alittle confusing.."
 
"Yes Sir Do need a Manual.Do h

"Yes Sir Do need a Manual.Do have the timing light.Just cant seem to figure out what marking I am supposed to go off of in order to make sure I am at 21 degree's before TDC for max advance.I have seen multiple sites the procedure to set this timing and have done it but for some reason just doesnt seem right.One reason is I set my timing etc. on my vehicles no problem but this one is different just doesnt seem to make sense.And yes I have been told this is a totally different ball game.One thing for sure I am going to get this running right,I didnt buy this to become a yard ornament,and with the help from you guy's I am sure it will work.Thank You..}"
 
"800 (80,0) 2559001 -

"800 (80,0) 2559001 - 2783252 1969 4 cyl
800 (80,0) 2783253 - 2986443 1970 4 cyl
800 (80,0) 2986444 - 3186282 1971 4 cyl
800 (80,0) 3186283 - 1972 4 cyl
800 (80,0) 9004402 - 1972 4 cyl
Yes 1972,compliments of TMD,
There is no pointer on the merc800,I own one myself,my black beauty is 1969. There is,should be a straight line on the flywheel to the right of the three dots.That is the timing set mark.
Set to TDC,remove the timing belt cover,remove timing belt,move the flywheel until the center of the flywheel, the straight line and the center of the distributor are in line.Turn the pulley wheel until the arrow is pointed at the straight line on the flywheel,hold pulley wheel and refit belt and put back together.She should now fire as the three dots pass TDC mark on the timing decal on the frame,#18 http://www.crowleymarine.com/mercury_parts/445/10.cfm .
Do get a manual as Jeff says and do a compression check.
I use champions L76V,gap less,or NGK BUHW and it's 23 BTDC max timing.
Have a look on the starter bracket,there may be a number there and should match 3192883"
 
"Thanks for the response Mr. M

"Thanks for the response Mr. McBride but unfortunatly On my flywheel there is no staight line and as far as compression Nr.1 is at 120 and 2,3,and 4 are at 130.Is it possible that I can use my dial guage on Nr.1 cyl find tdc and make a mark/line to line up with the tdc marking on the decal thats on the frame."
 
On another note I was told tha

On another note I was told that with today's gasoline its better to run at 21 degree's max advance.And you and the factory spec's indicate 23 Degree's as does the decal on the motor.
 
"Only my bank manager calls me

"Only my bank manager calls me Mr. when he invites me in
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.Compression #'s are good.Set TDC,remove the belt cover and belt,there is a small outshot on the pulley wheel and one on the plate below.Line these one over the other and fit the belt.If they don't line up exactly the pulley out shot should be slightly left of the lower one,will look like a half tooth out,that's ok.That should bring it right on timing.
It's gas/oil mix,regular,I would set it at 23 degrees,I do,but this side of the Atlantic we don't have as much ethanol in,yet.Next year."
 
"Update:I looked at the flywhe

"Update:I looked at the flywheel and noticed there are 3 dots on the oppisite side of the flywheel and thought let me take the flywheel off flip it around and see where it ends up.And here are the results,the flywheel (3 Dots) at TDC line up exactly with the TDC mark on the decal.Moved my Distributor gear to line up (arrow) with the 3 dots on the flywheel.Bolted everything back up and started her up.Put the timing light on it and she shows approx.2 degrees before TDC whith the 3 dots. throttle response is pretty good.Didnt rev it up to high due to it being on the muffs.Does not run to shabby.Will take it out to the lake sometime in the near future with some fresh gas and do a link and sync and see how it works out."
 
"<[img]"http://www.marineengin

"
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Only straight line on Merc800 #2881082 and below.I also took the liberty of emailing you some reading material until your manual arrives
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.Sounds as tough you got the timing anyway."
 
I am wondering if a Voltage Re

I am wondering if a Voltage Regulator Rectifier JOHN DEERE 318-420 would work instead of the original recitifier.I am thinking this would be a good Idea.Would this help concerning switchbox and battery..
 
Most people buy a Radio Shack

Most people buy a Radio Shack item that's about 5 bucks. Works great from what I hear.

Jeff
 
"Yes your right I had one inst

"Yes your right I had one installed and works,I was just curious about it being an upgrade Because of the regulator part."
 
"There is no regulator on that

"There is no regulator on that model, believe it or not. They make minor amps at idle, and too much voltage at WOT. But it seems to work. Need to keep an eye on the battery electrolyte level.

Jeff"
 
"I have tried the radioshack o

"I have tried the radioshack one and it works,but as you stated 17 volts @ WOT kinda scares me therefore I was wondering john deer regulator/rectifier would cure that problem and cheaper than $80.00.Might even prolong the life of the stock switchbox???"
 
"Steve I don't honestly kn

"Steve I don't honestly know if it would work or not.I have read in other posts here about standard auto parts,ie battery,ignition switches, not been compatible with marine usage. But if the radio shack one is working and you get a season out of it,at $5 a throw,that's a lot of seasons in $89,I had a look at the price.And I have no idea what a John Deere reg. rect. costs.
Crossed battery wires or a voltage spike from the stator would your main concern as far as the switch box is concerned,I think
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,I'm open to correction there."
 
"The 17 volts is a touch high

"The 17 volts is a touch high but would only affect the battery (at 16 volts I wouldn't even be concerned - that would be normal).

The ignition gets it's power directly from the stator (and from different bobbins than the charging side of things) - it appears as a single unit (the stator) but it can be 2 or 3 distinctly different components feeding different things - and they don't cross paths with each other....

If a regulator or rectifier fails and the charge power has "nowhere to go" it can take out the charge coils (bobbins) in the stator which may then take out the ignition bobbins and ultimately fry the switchbox (if equipped).

It's for that reason that 2 rules should be followed. First, never run the engine without a battery properly connected (that lets the power from the charge coils go somewhere - if it must be run without a battery, the regulator or rectifier feed wires must be disconnected and those wires must, at minimum, be grounded to the powerhead block, or more properly connected to an isolation block which has been installed for that purpose) - second, spend the extra few bucks and use a "MARINE" battery.

A regular car battery has thinner plates which are better suited to fully regulated power such as you get from your vehicles alternator/voltage regulator. A marine battery is specifically designed to act as both a regulator and capacitor for the unregulated power that many outboards produce...."
 
"Thank You for the Info.With t

"Thank You for the Info.With that being said I guess I wont worry to much about the recitifier,my Stator seems to be in good shape no visible defects,battery does show it charges when the motor is running.I do have to confess I dont have a Marine Battery I have been using a Yellow Top Battery.Maybe (One of these Day's )I'll have her all healthy and good to go_On a more joking note by the time this happens Ill be divorced and have to sell her
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Thank Guy's..."
 
"Happy New Year, I just wanted

"Happy New Year, I just wanted to pass along a update on my boat. My son and I decided to take her out this morning(to the Lake)and see what she’s got. Well first things first we did take the lower unit down to line up forward and reverse. We thought we had it(in the driveway)but when we put her in the water and finally got her started (hard to Start Cold Blooded).We let her warm up on the trailer and decided to give it a go. Well when trying to put her in reverse the shifter would not go just a little bit further to completely engage wouldn’t go past the little grind before totality engaged. Not a problem though just have to take the lower unit back down and move the shifter rod. Anyway got her out on the open lake and let her have it. Man o man was I impressed excellent hole shot and cruising right along. We stopped decided to set the max advance timing with timing light, got it @ 23 degree’s BTC. Runs pretty good, can’t tell what RPM she’s running at because my RPM gauge is not working. Hooked it up to the brown connecter on the switchbox but no go maybe I will try with the rectifier on the stator side. I do have a speedometer but I really don’t believe it work’s right. According to it we were only doing approx. 28-30 MPH. It seemed a lot faster than that. Anyway I want to thank this forum and all the good people here that have helped me getting this boat on the water and enjoy it as meant to be.."
 
"Now I think I do have another

"Now I think I do have another problem that I have no Idea. I tried to adjust my lower unit to get it to shift into reverse. It wants to shift into reverse but it just grinds/Clck,clack,clack. So I took the lower unit off to see if it goes into reverse and it does however when I hold the drive shaft and try to spin the prop, Its hard but it slips(kinda seems like in jumps in and out of gear. Another example in reverse when turning the prop. it turns the motor over maybe 2 rotations and then clicks (jumps)a couple of turns and grabs again both ways. The prop is not spun because it will turn the motor in forward gear all day long. My lower unit has these numbers on it 1623-6658 tried finding it online but no luck yet. And yes one other question let her run today in the driveway to check the charging I don't think that's working right either Battery shows 12.44 volts I give it some gas and it drops to 12.38 checked voltage at the switchbox were the 12 volt comes from the rectifier 12.44 is my rectifier toast. Other than that runs good but I don't think I will be going to the Lake this weekend shucks."
 
"Hi Steve check the rectifier

"Hi Steve check the rectifier and the stator,ref. Grahams note that a toasted rectifier could take out the stator
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"
 
"I started working on my boat

"I started working on my boat again and have done the following,fresh carbs,new switchbox,radio shack rectifier,new dist.cap,new distributor,new coil,new marine battery,new fuel pump.Motor runs but is missing bad on 1 and 3 cylinder,hooked a timing light up and put it on all four spark plug wires and 2 and 4 timing light good,1 and 3 3 you can see it cuts out.what should I look for here to solve this,is maybe my stator messed up??"
 
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