merc 305 i/o will not start

[jmalecek]

Hey guys, I have been a outboard guy in the past, and picked up my first i/o a few weeks ago.
1987 wellcraft 210 classic, 305 thunderbolt iv, alpha 1 gen 1.
On the test drive it rode good, it was a little boggy out the hole.
Last weekend it took a little to get it started on muffs, but ran till I assumed it was out of gas since it had 1/8 tank and the angle it was parked.

This weekend I put 5 gal of gas in it, but would not start.
I pressed the accelerator pump on the Q-jet carb and it did squirt in the primarys. When I had the spark arrestor and cover off the top, I did notice the rod that runs the choke flap from the divorced choke was missing. Held the choke closed and began cranking operating the throttle from neutral and up, no joy.

Pulled plug #1, it has spark but it's a faint yellow spark.I am use to old car engines that put a nice blue spark across .045 gap or so. I also noticed the spark gap is quite narrow on the plugs, is this normal?
I put a test light and volt meter on the coil, test light grounded to the thermostat bolt shows hot on both leads on the coil, and the volt meter shows +11.8 dc on both the + and - side of the coil. From what I know of working on cars, only the + side is hot, not both leads.

So my questions are:
1. Is a faint yellow spark normal on these i/o's?
​2. What is the recommended gap on plugs?
3. Where is the part number located for the carb? Is it on the red mercruiser tab attached to the corner?

Sorry for the novice questions. I spent 3 hours trying to get plug #1 back in and the socket off of it. My back and knees are still killing me from being cramped in the little engine hole.
I figure I will need to rebuild the carb and fab a choke rod from a piece of metal coat hanger. What I'm really looking for is input on the spark, and if that is the more pressing deamon to exercise.

BTW.
Merc 305 w/quadrajet, alpha one gen 1, 1.65:1 sn: 0b714730

 

[jmalecek]

I should mention, after pulling the #1 plug and checking spark, I did sand the electrode and post, but same result. Faint yellow spark. The plug was a bit dirty but defiantly not fouled.
The readings on the volt meter taken at the coil were after several attempts to start, but should still be valid.

Thanks,
Jamie

 

[alldodge]

Hey guys, I have been a outboard guy in the past, and picked up my first i/o a few weeks ago.
1987 wellcraft 210 classic, 305 thunderbolt iv, alpha 1 gen 1.
On the test drive it rode good, it was a little boggy out the hole.
Last weekend it took a little to get it started on muffs, but ran till I assumed it was out of gas since it had 1/8 tank and the angle it was parked.

This weekend I put 5 gal of gas in it, but would not start.
I pressed the accelerator pump on the Q-jet carb and it did squirt in the primarys. When I had the spark arrestor and cover off the top, I did notice the rod that runs the choke flap from the divorced choke was missing. Held the choke closed and began cranking operating the throttle from neutral and up, no joy.

Pulled plug #1, it has spark but it's a faint yellow spark.I am use to old car engines that put a nice blue spark across .045 gap or so. I also noticed the spark gap is quite narrow on the plugs, is this normal?
I put a test light and volt meter on the coil, test light grounded to the thermostat bolt shows hot on both leads on the coil, and the volt meter shows +11.8 dc on both the + and - side of the coil. From what I know of working on cars, only the + side is hot, not both leads.

So my questions are:
1. Is a faint yellow spark normal on these i/o's?
​2. What is the recommended gap on plugs?
3. Where is the part number located for the carb? Is it on the red mercruiser tab attached to the corner?

Sorry for the novice questions. I spent 3 hours trying to get plug #1 back in and the socket off of it. My back and knees are still killing me from being cramped in the little engine hole.
I figure I will need to rebuild the carb and fab a choke rod from a piece of metal coat hanger. What I'm really looking for is input on the spark, and if that is the more pressing deamon to exercise.

BTW.
Merc 305 w/quadrajet, alpha one gen 1, 1.65:1 sn: 0b714730

Your getting spark, faint yellow is not the best but you have spark.
Plug gap is .035 and AC MR43T plugs
Your carb number should be 1347-804624R1m it will be on the tag and stamped on the body of the carb

O think your issues is more bad gas or clogged filters even with a yellow spark

 

[jmalecek]

Thanks, I'll try filters this weekend.

 

[Watermann]

Check your cap and rotor as well as wires. If you have a QJ the number is on the throttle side and is vertical. The sensor under the rotor is also a source of similar problems with it starting one time and not the next.

 

[jmalecek]

Thanks for the info guys, swapped the fuel water seperator and that thimble filter in the carb.




Pretty nasty. I dumped in a bottle of heat. After a little priming and a shot or 2 of ether she fired up.
Ran @ 800 rpm til 160* then dropped to idle until it hit 175. I was happy to see the t-stat works .

All n all I ran it about 20 min or so, never went above 1100 rpm or 175*.
Fixed my missing choke linkage too. 3" piece of metal coat hanger bent just rite. Got it connected to the lever in the carb and to the choke flap. I was amazed it works the first time with no tweaking or binding.

Now to order up a new bilge pump or just the float sw and she's splash ready.

Waterman, I left that out in the first post. Sanded the contacts in the cap and rotor.

Thx again,
Jamie

 

[Bondo]

Ayuh,.... Ya might wanta plan on carryin' extra fuel filters for awhile,... That's Nasty,.....