1987 mercruiser 3.0...

[youknowmongo]

I have a 165hp mercruiser in a galaxy Admiral. The out drive is an alpha 1 I/o

Its having a problem starting, the engine cranks, turns, just like it should but its not catching. When it does catch, the engine shakes and rattles until it dies. When of does catch and start near the end of the battery, it shakes and rattles less. Occstionaly it will stall about 5 minutes of running and need to be restarted, and its the same process with near killing the battery it will run just fine until it sits for a few minutes.

I've recently added seafoam to the fuel, after the problem started. And ran it through the carb. I noticed that during its usual shake and rattle bit that the smoothed out a lot quicker then usual. Boat was out of the water(same as in)

I've changed spark plugs, checked fluids. Checked fitting

There is not a water separator on the fuel line (I'm currently working on installing)

I use chevron 89 octane gas, not a quick stop special

I'm about ready to throw in the towel, and take it to a shop, but I'm cheap, and would rather learn how to fix the problem my self.

The battery is brand new, not a month old.

I'm curious weather it may be the carb, started, coil, distributed, water I'm the fuel, or if theres something I'm missing. Its a great boat, fun on the water, we'll taken care of (bought it off craigslist from a retired coast guard...no BS)

Would appreciate any input to get back out on the water and not sitting with a stalled boat at the dock holding up traffic

 

[achris]

Re: 1987 mercruiser 3.0...

I have a 165hp mercruiser in a galaxy Admiral. The out drive is an alpha 1 I/o

And the thread title says 3.0l... Huston, we have a problem. If it's a 3.0l, then it's 140hp. If it 165hp, it's 3.7l.... Please post engine serial number so we can clarify exactly what we are trying to work with....

Its having a problem starting, .... I'm about ready to throw in the towel, and take it to a shop, but I'm cheap, and would rather learn how to fix the problem my self.

Now I really like you....

The battery is brand new, not a month old.

I'm curious weather it may be the carb, started, coil, distributed, water I'm the fuel, or if theres something I'm missing. ...

Right, the first place I start when dealing with 'strange' problems is to return to basics.... Do a compression test and ensure the engine is at least basically mechanically sound. Should be done on a warm engine, all plugs out, throttle at full open, then crank with the gauge in each hole for about 4-6 compression cycles. Pressures should be within 20psi of each other......

Chris............

 

[cr2k]

Re: 1987 mercruiser 3.0...

I'm betting the points need some attention.

 

[Aatcman]

Re: 1987 mercruiser 3.0...

You said this happened after you changed the spark plugs -- sounds to me like you got the firing order wrong -- check to make sure your firing order is correct.Also bring the front (forward, #1) piston all the way up at the top of it's stroke, on its compression stroke, and make sure the rotor in the dirtributor is pointing at the #1 spark plug terminal.. If not, then you probably changed either the firing order or you used a different terminal for #1 on your new distributor cap than you had been using on the old one.. Easy way to prove the second scenario is hook up a timing light and see how far off your timing is..Hope this helps! : o )

 

[magic11305]

Re: 1987 mercruiser 3.0...

I had the same problem on my merc 3.0 a couple years ago. After throwing money at the fuel system I finally fixed the problem with a new set of points and a new........condenser. Ended up being the condenser, never had one go bad......ever.

 

[youknowmongo]

Re: 1987 mercruiser 3.0...

Sorry for the delay. You are right, it is a 3.7. I didn't get a chance to grab the serial numbers, but I did have a chance to pull the Distributer cap, and was surprised it had a little bit as far as signs of wear and was pretty clean. I'm not sure if it was replaced before I bought it, or if it had been clean not to long before I bought it. I did, however notice the wires for the spark plugs were on the loose side...

Speaking of spark plugs when I replaced them, I did them one at a time then pit the boot back on and moved to the next one just because I can see my self swapping the wires.

Had 1 other person suggest the points, I'm thinking wires may need to be replaced. And I'm going to Google the condenser. Hopefully when the rain passes, or shows up at all I may have a chance to give everything else a look.

Thanks for the input all. Anymore, is still greatly appreciated

 

[achris]

Re: 1987 mercruiser 3.0...

Like I suggested, start with the basics. If this is a new boat to you, you need to get to a 'baseline' of maintenance and to know the condition of your engine. Do the compression test, and write down the numbers. This will be your reference for the future. Then do a FULL tune. As you don't know what was (and more importantly, what WASN'T) done before you bought the boat. So, NEW, plugs, points, rotor, condenser, cap, wires if they need it. ALL the filters, and new engine oil. I would strongly recommend you pull the heat exchanger out and have a radiator shop clean it out. Then move to the drive, and do a full service on that too, especially the impeller with the 3.7s... While you have the drive off, check your engine alignment, and grease the gimbal bearing and the unis (and all the other grease points on the gimbal housing).... Check the condition of the uni bellows and the shift bellows, and make sure the upper shift-shaft seal is the new style....

You do have one option (and I would most certainly do this), instead of new points and condenser, put an electronic option in, like an Ignitor II, and Pertronix II coil....

chris.........