1987 4.3 won't start....

Trailbum

Seaman
Joined
May 2, 2001
Messages
64
Hi Guys, <br /> Haven't been here in a long time... This is my Dad's boat, 1987 Starcraft, 4.3 w/Rochester 2GC carb and points distributor. He runs it only a few hours each Summer. Adds fuel stabilizer and has it winterized in the Fall. This Spring he put the earmuffs on it and she started right up as usual. Put her in the lake, started right up but stalled a few minutes later and would not restart!!<br />Worked on it until we ran the battery down... It appears to me that it's getting a weak spark, as the spark plugs were soaked with fuel each time I removed them and it would not fire even with starting fluid.... I hooked up a spark tester and seem to be getting a weak and intermittent spark at each plug (but it ran OK until it stalled). I pulled the hot lead from the coil and the end was oil soaked!!! Now I'm not sure if this can be attributed to a leaking coil or if it happened when he had the oil changed when it was winterized last Fall (the coil is right next to dipstick tube). I also pulled the top off the carb to verify the needle valve was seating. After researching past posts in this forum, my plan of action is as follows:<br /> Complete Tune-up; plugs, points, condenser, cap, rotor, wires, and coil. I will also have a rebuild kit on hand for the Rochester 2GC and extra float. I also have a 6-gallon remote tank to hook directly to the fuel pump for test purposes if needed. I'm bringing a dwell meter, timing light, vacuum gauge, digital voltmeter, vacuum pump, battery charger, etc. Trying to think of EVERYTHING I might need beforehand, because once I get up there (16 hour drive to Northern Maine & NO internet access), I'm really on my own!!!!<br /> Now someone correct me if I'm wrong here but I THINK the engine specs are as follows: 1987 4.3, 2-bbl: Spark Plug Gap .035??, Point Gap .019??, Timing 6 BTDC??, Idle 700-800??, Dwell 29-33??<br /> Now a couple quick questions... is the fuel/water separator before the fuel pump and looks like an oil filter??? Also, there is a 3-pin connector w/light blue wires running across the intake manifold. It looks like one of the wires goes to a contact switch on a bracket behind the carb.... This connector is unplugged and both ends are lyng on the intake manifold. I have no idea what this connector is for and either does my Dad, and we're not sure if it's unplugged for a reason or even how long it's been unplugged... We're thinking we should leave it as is since it ran OK in previous Summers....<br /> Quick question about parts... I've researched and obtained the Sierra Marine part numbers (18-xxxx) for all the parts I think I need. I know I've gotten Sierra parts from NAPA stores in the past, but does anyone know if NAPA can order the parts based on the Sierra part numbers I provide, or do I have to go through the whole charade of year, make, model, engine displacement, zip code, phone number, etc, etc???? Also, where can I get belts (Alt & P/S pump) or belt part numbers?? I didn't see belts listed on any of the sites I checked!!!<br /> Can anyone think of anything else I should be checking or any other tips and advice for getting this beast running again??? Like I said, once I get up there, I'm pretty far removed from everything (internet), but there IS a NAPA close by!!!! Thanks in advance Guys and sorry this post is SO long!!! <br /> Bill
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,082
Re: 1987 4.3 won't start....

1st Off,....... If you used a paragraph now,+ then,... Your post would be Much Easier to read,...................... ;) <br />
is the fuel/water separator before the fuel pump and looks like an oil filter???
Ayuh,........ That's Correct.......<br />
but does anyone know if NAPA can order the parts based on the Sierra part numbers I provide,
Ayuh,......... NAPA sells Sierra parts,+ uses Sierra Part #s..........<br />The belts can be Matched, or looked up by application........ NAPA Should have them......Or Can get them...........
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: 1987 4.3 won't start....

I think your weak spark will probably be taken care of by a tuneup. Points are probably glazed over.<br />You say it's a 4.3, but is it a Merc, OMC, Volvo???? Without knowing, it's hard to say what that 3 wire plug is.
 

Trailbum

Seaman
Joined
May 2, 2001
Messages
64
Re: 1987 4.3 won't start....

Thanks Bondo!!! Sorry Don, it's a 1987 Starcraft w/OMC outdrive!!
 

Trailbum

Seaman
Joined
May 2, 2001
Messages
64
Re: 1987 4.3 won't start....

While reading the "No Spark at Coil" post, I looked at the OMC wiring diagram posted by Don S and determined the connector that is disconnected on my Dads boat is for the "Interruptor Switch" and the "Overstroke Switch"... What exactly is the function of these switches... and why would the previous owner have disconnected them???? Thanks in advance!!!
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
13,026
Re: 1987 4.3 won't start....

Interrupter switch lets you get into neutral by lowering the idle speed while shifting, the overstroke switch is supposed to keep the interrupter from engaging when it is in gear since the boat would not run right then. Why they disconnected it is anyone's guess but I bet they were having shifing problems (stalling while shifting). That is supposed to be connected and it does make the shifting smoother when it is working as designed. The transom shift cable may have been getting stiff and that may be the root of the problem. Best bet is to find an OMC expert and get it set up right from the start.
 

Trailbum

Seaman
Joined
May 2, 2001
Messages
64
Re: 1987 4.3 won't start....

Thanks Lou!!! Guess I'll get the engine running reliably before I mess with the interrupter and overstroke harness....
 
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