'84 Merc 150 - how do I adjust timing?

[Dukedog]

Re: '84 Merc 150 - how do I adjust timing?

I did it by ear, on the water.

If you did MAX this way then like said "your problems may be over soon"! It ain't no chevy..........Use a light, lock it in at 18 ta 20 "crankin'" speed" and leave it alone............

COLD carb. V6 merc/mariners all have they're own little "quirks" ta start. One thing is common for all though. It takes a lotta fuel ta start a "cold" motor................

 

[MAtkins]

Re: '84 Merc 150 - how do I adjust timing?

OK if I understand correctly, I set the max spark advance at 18? to 20? and leave it.
But to set the idle correctly, tweak the primary pickup screw.

The max screw is pretty sensitive.
If I go too far in either direction the engine will bog when I try to accelerate.
I'll have to put a light back on it to check but it's about where it was. It's gotta be pretty close.

I *really* don't want to end up with a blown motor.

 

[Dukedog]

Re: '84 Merc 150 - how do I adjust timing?

OK if I understand correctly, I set the max spark advance at 18? to 20? and leave it.

Do this in tha driveway or garage. You can do it with all plugs removed but they will need ta be grounded to prevent any possibility of messin' up any 'lectrics. Just make sure they are clear of any of tha spark plug holes. It will get tha motor to a better "crankin" speed. If for some reason tha starter "kicks out" to quick place one plug at a time back in tha motor till tha starter continues turnin' tha motor over. Make sure tha advance timin' arm is hard against tha stop on tha block. You can do this with a bungee strap. It will free up both hands...

This is for "IDLE TIMIN' ONLY"

"6. Put it in tha water, in gear and adjust tha IDLE TIMIN' SCREW" til YOUR HAPPY............"

 

[wired247]

Re: '84 Merc 150 - how do I adjust timing?

Once again. If you disconnect the carb linkage and push the throttle forward it will rev the motor up to as high as the engine will run on idle jets alone ( 2000 or less ) with the timing fully advanced. Its not in anybodies book but it still works and the timing does not vary any from what you'd find at 6K WOT. I do it with every motor I run . Its quick, its easy. Its dead nuts accurate for setting WOT timing . It doesnt **** the neighbors off too much and I can do it in my garage.

 

[MAtkins]

Re: '84 Merc 150 - how do I adjust timing?

Well, I set the max advance timing to about 19? BTDC @ cranking speed, throttle pushed to WOT.
I used a standard timing light.
I made sure the stop was hard against the block.

I took the boat out and it ran like crap.
First off, when I tried to go to WOT it just stalled, repeatedly.
Finally it warmed up enough to keep running but it wouldn't open up and take off.
I did get it to top speed once.
I was running as fast as I could get it to go and it finally, slowly started gaining speed.
Eventually it planed out and took off.
I couldn't get it to do it again.

The motor won't rev up to plane with the max advance timing set at 19? BTDC.

What should I do now? I fear scrap the motor?

 

[wired247]

Re: '84 Merc 150 - how do I adjust timing?

Try another timing light.

 

[Dukedog]

Re: '84 Merc 150 - how do I adjust timing?

Sounds like somethin' else went south. Stator, switch box, fuel pump, carbs? Really hard ta tell on a screen............

 

[MAtkins]

Re: '84 Merc 150 - how do I adjust timing?

I cleaned & rebuilt the carbs & they 'seem' fine.
I did use a cheapo timing light. Can it be that far off?

Is it possible that the motor's just shot?
How do I troubleshoot it?

 

[wired247]

Re: '84 Merc 150 - how do I adjust timing?

I'd see if I could borrow another light from someone. Motors don't just up and become shot. If you have good compression you might want to try a leakdown test but you'll have to borrow , rent. or buy a leak down tester. If your leakdown is OK which it probably is if your compression is good then something else is wrong. float level settings, timing, stators etc. can drive you out of your mind but once they are fixed you'll forget all about it.

 

[MAtkins]

Re: '84 Merc 150 - how do I adjust timing?

I do suspect the compression.
The last time I checked it each cylinder was between 105 and 80.
I used a seafoam procedure on it twice, left it a few nights with seafoam in it, twice.
I got suggestions here that the compression might not be all that bad, especially after I seafoamed it.
I haven't checked compression since then.
I meant to get that done today but didn't get to it; tomorrow maybe.

I'm having a hard time justifying a complete rebuild on an '84.
I think it'd cost more than the value of the motor.

 

[wired247]

Re: '84 Merc 150 - how do I adjust timing?

80 lbs is not good. Your motor needs a rebuild. Try leading with that next time.

It would cost you less than a new motor or even a good rebuilt motor to rebuild the one you have. $1500 max. What difference does the resale value make? You need a motor.

 

[MAtkins]

Re: '84 Merc 150 - how do I adjust timing?

I did address compression on this forum. It just wasn't this thread.
I was advised that maybe the compression wasn't so bad and it should get better after I get the carbon buildup out of it.

I can get a rebuild kit on ebay for $1K but it'd be $450 to have the cylinders bored.
I don't know how good the kit is or whether or not I can get away with just running a honer on a drill through the cylinders.
Then there's stuff like replace the switchbox? stator? reed block? etc.

 

[Dukedog]

Re: '84 Merc 150 - how do I adjust timing?

I did it by ear, on the water.
If I just bump the key to engage the starter, the motor starts.
It idles great, with the throttle arm against the idle stop screw, & with a gap between the throttle cam and the carb linkage roller.
When I nail it to WOT right of the idle it takes off and planes out beautifully.

The boat ran much better today than it has since I got it.
THANKS!!

How do go ya go from this ta what ya got now?

Your comp does suck IF tha gauge is a "KNOWN ACCURATE GAUGE"

Cost of rebuild is where 247 and I are way off. There is a "fix" and there is "rebuild". No mater what ya do, DO YOUR HOMEWORK..........

 

[wired247]

Re: '84 Merc 150 - how do I adjust timing?

I did address compression on this forum. It just wasn't this thread.
I was advised that maybe the compression wasn't so bad and it should get better after I get the carbon buildup out of it.

I can get a rebuild kit on ebay for $1K but it'd be $450 to have the cylinders bored.
I don't know how good the kit is or whether or not I can get away with just running a honer on a drill through the cylinders.
Then there's stuff like replace the switchbox? stator? reed block? etc.

Pistons with rings $440 or less
Gaskets $100
Bearings $220 if you change them all
Bore and hone job $380 with shipping.
fiber reeds $120
stator $150 probably dont need it but your still under budget
Carb gaskets $100

Thats $1510. some stff on there you don't NEED bt its enough to give you essentially a new motor. Throw $30 in for a water pump impeller. Don't change switch boxes unless you need to. Thats $1540 for a new motor. Priced a new motor from Mercury lately? $9000 from a cheap dealer for a 150. Paying someone else to do it for you...why the hell would you do that? Man up. grab a wrench. Get to work.

 

[MAtkins]

Re: '84 Merc 150 - how do I adjust timing?

I've had the problem since I got the boat.
Funny though, the seller took it out on a lake and it ran great when I bought it.
I was never able to make the boat run like that after I bought it.
I know they didn't set any timing or throttle, the screws hadn't been moved in years.
So, I don't know how they got it to run. Maybe oil lean gas?

The compression guage is a cheapo $20.00 one I got off ebay.
It may be off but the #1 piston is showing 80 and the rest are between 90 and 105 (last I tested it).
That would indicate a problem even if the gauge is off wouldn't it?

It ran great for me that one time because I advanced the max timing advance way too far.

How big a job is it to rebuild? How many hours (ballpark)?
The carbs are done.
I'm pretty mechanically oriented, have rebuilt an older car engine but never an outboard.
I'm sure I lack tools though; a hoist; a stand; a torque wrench . . .

Where can I get the block bored for $380?
Where do you buy the parts (pistons, bearings, seals, gaskets, etc.)?
I didn't see seals in your cost analysis.

What do you think of this:
Mercury Mariner 135 140 150 HP 2 5L Carb V6 O Ring Powerhead Rebuild Kit | eBay
or this:
MARINE ENGINE REBUILT

 

[wired247]

Re: '84 Merc 150 - how do I adjust timing?

Chris Carson marine will give you a good deal on the gaskets, bearings and such. Below what you'll find on ebay . On those early pistons ebay can be your friend. Rucks Machine in Wisconsin will do the block for less than I quoted. You only have 3 lip seals in that motor and they come in the gasket set.

As far as the labor to rebuild its considerably easier to do one than it is to rebuild a car engine. No valve train so 2/3 or the job is missing from what your'e used to. You don't need a stand. Just a work bench. You do need a torque wrench but if you don't have one you need one anyway. The flywheel puller is really the only specialized tool you'll need and they are $30. Don't need a hoist either. 2 guys can pull the powerhead off easily if you strip the powerhead of accessories and such before you pull the motor and reinstall it stripped. I pull my own without help or a hoist. 120 lbs or so.

Neither one of those links you posted are for your motor. One is an inboard GM and the other is a 2.5 liter rebuild kit. You have a piston ported bottom guided 2.0/150. Different animal than the 2.5.

Its OK to have no idea what you are doing. That where people begin and this stuff is NOT difficult if you want to learn and are willing to try.

 

[MAtkins]

Re: '84 Merc 150 - how do I adjust timing?

I got the url wrong.
The guy just emailed me this after getting my serial #:
-------------
From: Samuel Agosto [mailto:happiemac@verizon.net]
Sent: Wednesday, November 20, 2013 4:20 PM
Subject: Re: Reed valves for '84 Mercury Mariner V6 2.0

Prices include ground shipping to the US.
Rebuild Kit - $900
Boyesen Reed Set - $140
Impeller - $18
Let me know and I can prepare a Paypal request for you.
--------------

He dropped the rebuild kit $100.00 if I don't buy through ebay.
http://www.ebay.com/itm/36079497867...l?_sacat=0&_from=R40&_nkw=360794978678&_rdc=1
It would cost me $1,132.06 with tax (I'm in Florida, so is he).
That's plus whatever it would take to get it bored.
Chris Carson says he'll do it for $200.00 + shipping.
Would there be an advantage to boring out to .030?

Chris quoted me
$110.00 for the gasket kit
$540.00 for the bearings

Dukedog: what did you mean by 'do your homework'?
I've got a Seloc and I've been buggin' the crap out of you guys (much appreciated) and the dealers.
Is there anything else I can do to ensure that this goes smoothly?
Remember, it's a currently useless '84 2 stroke 150 - not a hot rod )

 

[Dukedog]

Re: '84 Merc 150 - how do I adjust timing?

First off through tha Seloc in tha trash and get an oem manual. Think there's someone on here that can help with that. Tha machine work is a make or break deal. Research 'em wherever ya can. Research type of pistons. Don't bore it any more than is necessary to "clean it up". Not like a car motor where bigger is better. Be sure ta have tha heads and deck checked for being flat. Take off no more than necessary ta get heads and block "flat". Be sure ta tell tha machine shop ta do this. Ta me tha machine work is tha most imperative part of any kinda fix and/or rebuild...Parts is parts! Just some better than others.............Just no do-overs in machine work.

 

[Dukedog]

Re: '84 Merc 150 - how do I adjust timing?

First off through tha Seloc in tha trash and get an oem manual. Think there's someone on here that can help with that.

"carholm" on here might be able ta help if ya ask 'em nicely...............

 

[MAtkins]

Re: '84 Merc 150 - how do I adjust timing?

It looks like the machine work will need to be done before anything can be ordered.
Can I mix piston sizes? Like if one cylinder needs major boring but another one just needs cleaned up a bit?
Also, about how much should this block, stripped, weigh?

How can I research pistons? So far I've found them pretty hard to find (again, I'm not a pro outboard mechanic).
That is, I'm not sure what I can put in there. I haven't learned of any options or alternatives to pistons except their size.
I understand they're supposed to have a shaped head to handle the exhaust & intake ports.

I dropped a pm to carholme. Thanks for that reference.