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87TriStar
07-10-2007, 02:37 PM
I have a VERY tempermental 1987 351 Ford. First, I have installed a new starter motor, fuel filter, Edelbrock carb, plugs, wires,coil, electronic ign., celenoid (constantly). The typical scenario (although the boat always likes to surprise me with new variations of EVERYTHING) is the boat will start right up and run well for say 1/2 hour at relatively constant speed. Then if you start playing with your speed, particulally on the slow end, the moter gets a lot of hesitation sometimes cutting out, sometimes recovering if you speed up. At such times if you try to idle down such as to dock, it will cut out when you try to switch from neutral to reverse. Often it can take hours for the boat to restart at all and then you never know how it will behave - sometimes it will idle in neutral beautifully until you put it in gear and it stops dead; sometimes it will continue to run normally. Also during all of these times, if you try to restart boat during these times the celenoid will get smoking hot ( without grinding away on the starter motor - quick key hits). I would like to junk this motor but I can't afford to replace it right now and in this state the boat is totally unskiable. This boat has been babied from day one and is in absolutely pristine condition visually so it would really be a pleasure if it would actually take us out AND bring us back to the dock. Any worthwhile suggestions would be appreciated.

Monte
07-10-2007, 02:48 PM
I don't know what to say about the selenoid getting hot, but the idle problem sounds like the carb needs to be adjusted. Maybe the timing as well??


Mostly just a BUMP for you..

BTW let's see some pics.

87TriStar
07-10-2007, 02:51 PM
Yes, I forgot, we did also adjust the timing and play with carb adj.

TMCNo1
07-10-2007, 03:02 PM
Have you seen this thread, http://www.tmcowners.com/teamtalk/showthread.php?t=17651

Monte
07-10-2007, 03:03 PM
I got nothin... Somebody on here should be able to help. JimN is one that comes to mind.

betsy&david Harrison
07-10-2007, 03:06 PM
We had some similar trouble with our '93. Changed all the stuff you did and still had issues. Then we replaced a very old thermostat and the problem went away.

pilot02
07-10-2007, 03:35 PM
I'd check the vent line to the tank. Sounds like it may be getting a little vacuum in the fuel line and starving for fuel.

etduc
07-10-2007, 05:56 PM
I have a VERY tempermental 1987 351 Ford. First, I have installed a new starter motor, fuel filter, Edelbrock carb, plugs, wires,coil, electronic ign., celenoid (constantly). The typical scenario (although the boat always likes to surprise me with new variations of EVERYTHING) is the boat will start right up and run well for say 1/2 hour at relatively constant speed. Then if you start playing with your speed, particulally on the slow end, the moter gets a lot of hesitation sometimes cutting out, sometimes recovering if you speed up. At such times if you try to idle .....

I am no longer a fan of, Edelbrock carbs. I played with mine for 2 years.
Carb needs to be pretty flat, for proper fuel level. If you are running Edelbrock, I suggest buying a wedge-plate. (Cost about $40, from www.jegs.com) Float valves tend to stick. What do your new spark plugs, look like. wet or sootie.

Sounds like couple of problems. Heat sink, carb adjustments, possibly carb angle,etc.

Solenoid will get hot pretty quick. (I've ruin my share.) Old mechanic has told me, start no longer than 5 seconds, let cool for 60 seconds.

Are you using a marine grade solenoid? (They are sealed. Automotive type have a cooling vent, but lets moisture in. i.e.- corrosion) I ,now, swear by them.
.

EricB
07-10-2007, 07:09 PM
87...
So the engine will not crank at all when hot? I had an issue with slop in the timing chain on my 351 Ford. Ran great one minute, if I stopped it and restarted it ran terrible. Also would stall and the symptoms sound familiar.
Take an iductive iming light and check the timing. Run at a constant speed (about 2000~2500 rpm, neutral) and see what kind of variation you get in the timing, in other words look for it to bounce around.
If it bounces around more that 2 ~ 4 degrees at a steady state, you have "slop".

87TriStar
07-10-2007, 09:31 PM
Thanks for everyones reply thus far. Will try suggestions that have not yet been done? Will recheck timing...nothing to lose by redoing anything. Type of solenoid I do not know, so will look at tomarrow.
BUT WHAT IS "HEAT SINK"? Thanks to. all

TMCNo1
07-10-2007, 10:33 PM
Thanks for everyones reply thus far. Will try suggestions that have not yet been done? Will recheck timing...nothing to lose by redoing anything. Type of solenoid I do not know, so will look at tomarrow.
BUT WHAT IS "HEAT SINK"? Thanks to. all


Another term is heat soak, caused by the engine heat that was not removed prior to the engine being cut off being soaked thru the engine and heat buildup inside the motorcover causing gasoline vapor lock in the fuel lines and carb. This vapor lock causes hard starting and flooding from all the cranking being done to get it cranked.

etduc
07-11-2007, 10:33 AM
Another term is heat soak, caused by the engine heat that was not removed prior to the engine being cut off being soaked thru the engine and heat buildup inside the motorcover causing gasoline vapor lock in the fuel lines and carb. This vapor lock causes hard starting and flooding from all the cranking being done to get it cranked.

I meant "heat soak".

Try to eliminate, some items. This will take some time. After you run the boat and problem occurs. Did you check, if you are still getting spark to the plugs?

If you are, I would look for a fuel/carb/vent issue.

In my case. on the Edlebrock. The secondary jets where to big, and fuel bowl level issue. I believed contributed to running way rich, at higher speeds. (I had to use the flooded engine, start routine, to get it started. Also, I had an distributor problem, not helping.)

In the end, I trashed the two year old Edlebrock, bought a Holley 4160. ( I know, drastic measure. Life is better, now.)

Also, you could have multiple issues, which have snowballed on you.

jfr
07-11-2007, 10:48 AM
if you find out what the problem was please let me know . I'm having a very similar problem with my 1987 ford 351, i tried everything you have.

tommcat
07-11-2007, 11:41 AM
what kind of fuel filter do you have? is it one of the clear glass ones? if so those commonly cause vapor lock, on cars you can actually watch the gas boil in them as soon as you shut the engine off and it would probably be worse under the motor box of a boat.

EricB
07-11-2007, 07:02 PM
Just remember...If it cranks /turns over slowly (or very slow) it's not a fuel issue. If it cranks/turns over at a consistently good rate of speed, then it could be fuel or ignition.