1984 Islander with140 3 liter mercruiser yet again. When will I get it?

[rolmops]

So I took her fir her first test run after the rebuild and everything seemed dandy,she started well and she was running smooth. I had her running at 12/14/16 hundred and so on until 2000 rpm and it sounded real sweet. Next I tried a bit faster, but she would not go over 3200 rpm,this is with a 15/19 prop, so I figured I should try with a 15/15 although I am told that this engine is strong enough to push this roughly 3000 pound boat at 4500 rpm with a 19 pitch.
Then the bad stuff started happening.
All of a sudden the rpm gauge was all over the place (vibrating above 3000 rpm going back and forth while I did maybe 2000 and later only 1200) and the engine started to bug down and did some coughing and back firing (not strong but more like choking). I shut her off and let her sit for a minute,then turned the key and she started right back up,but after revving her up to 1200 rpm she started doing the same thing again.
My suspicions were that the timing had gone crazy, now I am more inclined to think that the distributor cap may be cracked (this is an electronic ignition with distributor).
In short,before I start throwing hammers, I need words of wisdom and advice. So please, if you have any wise words,I need them.
Cornelis.

 

[achris]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

Take a deep breathe, and say after me "I will not hurt this engine. It is just an inanimate object. It is not smart, like I am".... Then throw a hammer

Oh, oh, sorry, you want ENGINE advice... Sorry, fresh out...

 

[achris]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

Re-check valve adjustment and timing... Also throw a timing light on and make sure the plate in the dissy is moving and advancing the timing properly. You have a timing curve?

 

[rolmops]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

Re-check valve adjustment and timing... Also throw a timing light on and make sure the plate in the dissy is moving and advancing the timing properly. You have a timing curve?

Thanks, Once daylight comes I will recheck compression, valve adjustment and timing.
I'll check the innards of the distributor as well.
Thank you for your common sense words.

 

[achris]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

Ohhhhh, just occurred to me :facepalm: When you redid the engine and head, did the cam followers, pushrods, valves and rockers and all the rocker nuts and balls go back in the same place they came from? If not, were the rockers re-faced? If the answer is "no" to both questions, look for rockers that have 'fallen off' their valves when you lift the rocker cover....

Chris.........

 

[rolmops]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

It seems that I had the valves tightened backward at a 180 degrees just like I had the wires backward a week ago. It never downed on me that I did the valves backward as well.
Oh well, it's off to the lake for another try.
I can feel the difference with the engine starting up right away.
None of the rockers were off their rocker.

 

[thumpar]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

Years ago I redid the top end on a 4.3l. Same thing happened and it turned out to be some of the valves were too tight.

 

[rolmops]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

So that did not do the trick.
Even though the engine starts up way nicer,it did not solve the problem.
So on to the next suspect.
The alternator just did 13 volts tops on the old block,now she is up to 15.5.
Maybe the high voltage gets the electronic ignition to go haywire?
I'll see if I can find another alternator and go from there.
Compression is around 150 on all 4 holes and the timing sits right where it should be
I'll double check the valves

 

[airshot]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

The 15 volts should not cause a problem, my own alternator on my 3.0 runs at about the same voltage without a problem. And yes that 3.0 will push that Islander to 4400 rpm without any problem if everything is adjusted correctly. My 1983 Islander/ 3.0 will turn almost 4500 @34mph (gps) with two adults and all the fishing gear so yours should do as well. I am running a 14 1/2" dia X 19 pitch prop.

 

[rolmops]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

I'll change out the head,the carburetor and the electronic ignition. That should eliminate most possible causes for trouble.
I'll keep you guys updated

 

[rolmops]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

Ok. back to the engine.
I did a little stint in a hospital as a result of trying to lift things that are way to heavy,but now that I have to be home for 4 weeks to recover I can continue screwing up on my engine.
I did solve some things, like fuel supply by completely rebuilding the carburetor and an almost complete rewiring of the

 

[rolmops]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

Ok. back to the engine.
I did a little stint in a hospital as a result of trying to lift things that are way to heavy,but now that I have to be home for 4 weeks to recover I can continue screwing up on my engine.
I did solve some things, like fuel supply by completely rebuilding the carburetor and an almost complete rewiring of the harness and a replacement of the electronic ignition.
Rebuilding the carburetor and the wiring harness was a very good thing and badly needed doing. The electronic ignition was probably a waste of money and mostly the price I pay for not knowing what I am doing.
I did learn an interesting thing. It is possible to turn the oil pump at the bottom of the distributor shaft and by doing that,it is possible to completely screw up the timing. That was probably the main reason why the engine did not do what it was supposed to do. It took me a while to figure that out and then just took a long big screwdriver and put it back in the proper place so the timing can be set the right way. Anyway,another lesson learned.
This afternoon I put everything back together and turned the key over. It showed good signs of life. Tomorrow I will hook it up to the hose and try to start it.
I'll let you know what happens.

 

[Silvertip]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

So did you not use a timing light to set the timing after the rebuild? It doesn't matter one bit where the distributor shaft sits when it slips into the cam gear and oil pump. That's why the outer portion of the distributor is moveable -- so you can rotate the housing around the rotor to get the proper timing. Of course the proper way to do it is to get #1 piston at TDC on the compression stroke and then plop in the distributor with the rotor pointing to #1 plug wire. You then again use the light to fine tune the timing.

 

[rolmops]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

So did you not use a timing light to set the timing after the rebuild? It doesn't matter one bit where the distributor shaft sits when it slips into the cam gear and oil pump. That's why the outer portion of the distributor is moveable -- so you can rotate the housing around the rotor to get the proper timing. Of course the proper way to do it is to get #1 piston at TDC on the compression stroke and then plop in the distributor with the rotor pointing to #1 plug wire. You then again use the light to fine tune the timing.

That is what I thought, but my distributor is rectangular and it has very little room to turn. Besides,it has numbers on it -1-3-4-2- so I had to turn the oil pump in order to match the cylinders to the numbers. It was not necessary to do this but I wanted to prevent future mistakes.I do use a timing light and a timing shunt.

 

[rolmops]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

I just had the alternator rebuilt. It turned out that the stator went haywire once it warmed up and got over a certain rpm. I put it back on and things sound a lot better now.

 

[fishrdan]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

my distributor is rectangular and it has very little room to turn...... I do use a timing light and a timing shunt.

EST ignition I assume?

What are you timing the engine to, with the shunt in place and the ignition in base timing mode? Depending on the year, the 3.0 EST was timed anywhere from 1* ATDC to 2* BTDC (as memory serves), and when the shunt is removed timing should go to around 12*. I timed my old 140HP to 2* BTDC.

Also, if the EST is a replacement ignition, you need to verify that you're getting 12V (battery voltage) to the distributor. You may need to by-pass the resistance wire if the engine had points ignition before.

 

[rolmops]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

EST ignition I assume?

What are you timing the engine to, with the shunt in place and the ignition in base timing mode? Depending on the year, the 3.0 EST was timed anywhere from 1* ATDC to 2* BTDC (as memory serves), and when the shunt is removed timing should go to around 12*. I timed my old 140HP to 2* BTDC.

Also, if the EST is a replacement ignition, you need to verify that you're getting 12V (battery voltage) to the distributor. You may need to by-pass the resistance wire if the engine had points ignition before.

I do use a keyed 12 volt source and with the shunt I use 1BTDC.
Anyway, I started her up today and although at first it was shaking and running a bit rough ,after about half an hour it was running a lot better.
I'm afraid to say so ,but maybe I finally got it. I better winterize her quickly and put her away for the rest of the year.

 

[rolmops]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

There was only one problem left. Every time time I started it up it would run but it would also shake.
At least this was easy. It was a bad plug. Now she purrs like a kitten and she has been winterized and ready to be used next spring.

 

[Bondo]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

There was only one problem left. Every time time I started it up it would run but it would also shake.
At least this was easy. It was a bad plug. Now she purrs like a kitten and she has been winterized and ready to be used next spring.

Ayuh,.... Sounds Great Cornelis,.... All ready for Spring football Browns,....

 

[rolmops]

Re: 1984 Islander with140 3 liter mercruiser yet again. When will I get it?

Thank you Bondo.
Next spring I'll bring her up to the north country and try to do some brown fishing between the Islands in front of your home.