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Deanhamel
07-03-2009, 05:21 PM
I am trying to resolve a very perplexing problem with my 84 S&S Powerslot with a 351 Ford. I bought the boat last summer and immediately replaced the carburetor, starter, ignition wires, points, plugs, condenser, distributor cap and rotor. The boat had 598 hours on it when I bought it and suffered more from lack of use than anything else. After the upgrades last year, the motor ran like it was new. Very responsive, clean and powerful. A beautiful thing to behold! At the end of last season I discovered that the front transmission seal was leaking. This spring I pulled the transmission and replaced the seal. While the back end of the works were apart I replaced the transfer plate also. And since the original mufflers were still in the boat and a bit worse for wear, I replaced those too.

Upon launching the boat this year I am experiencing a decrease in the performance of the motor. It starts great but it exhibits the following symptoms:

ē The motor sounds and feels rougher.

ē When it is in gear it generally runs rough at low rpms (<2500) with a decrease in power.

ē It runs better at higher rpms (3000+) but there is still a decrease in power and smoothness. At this engine speed there will be intermittent surges in rpms of +/- 200 and when this happens, the engine feels like itís old self. Again this applies to when it is in gear.

ē The motor is not as responsive to the throttle. After the new carb last year response was immediate. Now there is a slight but obvious hesitation when coming off the line and acceleration is clearly compromised.

ē Sitting at the dock running in neutral the problem is still there but less significant, but because Iím so familiar with the motor, I can tell that something is wrong. It kicks over and starts with barely a twitch of the key but it idles rough. Moving up and down through the range of rpms it runs consistently, but it isnít smooth and clean.

At first I thought it was connected to the transmission work but I canít see how that could be. I discussed the problem with Vince at Discount Inboard Marine and he canít see a connection either. Iím thinking that perhaps Iíve got some residue in the carb from ethanol and winter storage so Iíve got some carb cleaner and dry gas to add to the fuel.

I did notice that my tranny fluid level is a bit high but can't imagine that would be the cause either.

I am thinkful for any and all ideas or suggestions!

corey
07-03-2009, 06:24 PM
My first guess would be something fuel related too. I'd try fresh gas and if you havent already fresh fuel filter. Second guess would be a bad plug or wire, I know they were replaced but everyonce in a while something is just not quite right.

Hoosier Bob
07-03-2009, 08:04 PM
After a good fogging for storage my boat will run like absolute crap every spring unless I replace the plugs. I see black smoke at the beginning of every season. Burn the fogging oil off then change the plugs. Also if the gas has not been treated you will have a bunch of crap in your carb. Believe it or not I have to change the plugs every year. Are you seeing any black smoke or is there a residue on the transom around the exhaust? Run some carb cleaner, Gumout and a cheap fix may be putting new plugs in.:confused:

Deanhamel
07-06-2009, 09:44 AM
No black smoke or residue on the transome.

Ran through 3/4 of a tank of gas after adding some dry gas and Gumout Carb Cleaner. Some notable improvement but sometimes it still runs rough below 3000 rpm. How do you determine when it is time to open up the carb for a good cleaning. The carb was new last July. Could it be that dirty already?

mayo93prostar
07-06-2009, 09:50 AM
are your mufflers installed correctly? If you have the old ones, I would put them back in and try it. I read on here a while ago that the mufflers have baffles in them and there is a certain orientation that they should be. a thought. otherwise, it may be plugs fouled or problem with fuel. check/replace all fuel filters (likely more than one) and then clean carb.

Deanhamel
07-06-2009, 10:16 AM
When I replaced the mufflers I replaced the exhaust hose from the manifold to the muffler on only one side. The hose on the other side was still in pretty good shape. However, the difference is that I used corrugated hose in the replacement to support a smooth bend whereas the old hose has a bit of a kink in it. Could the difference in back pressure be the cause?

Hoosier Bob
07-06-2009, 11:08 AM
Have you changed your plugs this season? What do you do when you winterize? It was fine, stored and now it is not, right?:confused:

btriantos
07-06-2009, 11:21 AM
double check your timing, or advance it slightly (a few degrees). Another possiblilty could be air/fuel mixture issue.

Deanhamel
07-06-2009, 11:22 AM
Right. It ran perfectly last fall and now it isn't running as well.

Last year was my first season winterizing a boat in 18 years. I changed the plugs last fall when I fogged the motor. After fogging through the carb, when I pulled each plug to spay fogging oil in the cylinder I replaced it with a new one. I changed the oil, put stabilizer in the gas, filled the block with antifreeze, pulled the battery, etc. One thing I know I did wrong was to add stabilizer to the gas tank after fogging (no laughing) so the gas in the system wasn't treated. Otherwise, I tried to follow the winterization instructions I found on this site.

Hoosier Bob
07-06-2009, 01:18 PM
Carb can varnish up pretty quick. My guess is as fogging oil is great it really f's up those crap Motorcraft Spark Plugs. Usually you will see some residue on the transom. If you started the baot first time with a belly full of fogging oil, carb cleaner and new plugs you have most likely shot the plugs. I will only replace the plugs after a 20 minutes or so on the fake-o-lake in the driveway. Boat runs like crap until I put all new plugs in. Good news is that this is a cheap fix. They do not like foging oil at all in my 351! Change oil in the fall and plugs in the spring. Last couple of trips out every year start mixing the gas with stabyl. Then when the weather turns to **** you will be ready.:DRight. It ran perfectly last fall and now it isn't running as well.

Last year was my first season winterizing a boat in 18 years. I changed the plugs last fall when I fogged the motor. After fogging through the carb, when I pulled each plug to spay fogging oil in the cylinder I replaced it with a new one. I changed the oil, put stabilizer in the gas, filled the block with antifreeze, pulled the battery, etc. One thing I know I did wrong was to add stabilizer to the gas tank after fogging (no laughing) so the gas in the system wasn't treated. Otherwise, I tried to follow the winterization instructions I found on this site.

Deanhamel
07-13-2009, 06:18 AM
Just to close out this thread for anyone interested, the problem has been completely resolved with a new set of plugs and a fresh tank of gasoline (93 octane) with a bottle of carb cleaner added. She ran perfectly all weekend. Thanks to everyone who helped out!

Hoosier Bob
07-13-2009, 04:58 PM
Nice to hear! I meant to say Autolite plugs. Get used to doing this every spring by the way!;)Just to close out this thread for anyone interested, the problem has been completely resolved with a new set of plugs and a fresh tank of gasoline (93 octane) with a bottle of carb cleaner added. She ran perfectly all weekend. Thanks to everyone who helped out!

Jim@BAWS
07-13-2009, 05:11 PM
DID YOU LUBE THE MUFFLER BEARINGS WHEN YOU PULLED THEM

VERY VERY IMPORTANT


Jim@BAWS

Hoosier Bob
07-13-2009, 06:10 PM
Those are only in the newer year boats with fuel injection Jim! Surprised you did not know that!;)DID YOU LUBE THE MUFFLER BEARINGS WHEN YOU PULLED THEM

VERY VERY IMPORTANT


Jim@BAWS

Deanhamel
07-14-2009, 09:41 AM
There wasn't anything like a bearing in the muffler work that I did. Hoses, clamps and new fiberglass mufflers - http://www.skidim.com/prodinfo.asp?number=288-3001. That was all. The skidim description of the mufflers says "Easy to install". In theory thats true. The reality of the hose clamps that secure the exhaust hoses to the transom that are located under the gas tank behind the steering linkage is another story!

Kingsley X-1
07-14-2009, 10:35 AM
There wasn't anything like a bearing in the muffler work that I did. Hoses, clamps and new fiberglass mufflers - http://www.skidim.com/prodinfo.asp?number=288-3001. That was all. The skidim description of the mufflers says "Easy to install". In theory thats true. The reality of the hose clamps that secure the exhaust hoses to the transom that are located under the gas tank behind the steering linkage is another story!

i am not sure what jim@BAWS is talking about :confused:, but i am taking from your posts that the pylon inner core-lube wasnt worn out was it???

Deanhamel
07-14-2009, 10:47 AM
not sure what the pylon inner core-lube is.

Jim@BAWS
07-14-2009, 12:00 PM
Be sure and check the PYLON BEARINGS ALSO...With them being greased the rope will not
turn properly































































PS...THIS IS A JOKE JUST LIKE THE MUFFLER BEARINGS. If you don find them make sure and use a LEFT HANDED METRIC CRESENT WRENCH for adjustments

Jim@BAWS
07-14-2009, 12:01 PM
Those are only in the newer year boats with fuel injection Jim! Surprised you did not know that!;)


As Johnny Carson would say "I DID NOT KNOW THAT"

Jim@BAWS

Hoosier Bob
07-14-2009, 12:33 PM
This is TT humor! No muffler bearings on your model! Your pylon needs grease every 4500 hours with regular use. More TT humor! Lol!There wasn't anything like a bearing in the muffler work that I did. Hoses, clamps and new fiberglass mufflers - http://www.skidim.com/prodinfo.asp?number=288-3001. That was all. The skidim description of the mufflers says "Easy to install". In theory thats true. The reality of the hose clamps that secure the exhaust hoses to the transom that are located under the gas tank behind the steering linkage is another story!

mccobmd
07-14-2009, 12:47 PM
Where do you drill the grease zert into the ski pylon???

Hoosier Bob
07-14-2009, 01:49 PM
No need just remove the top allen head/bolt and pump until full!:DWhere do you drill the grease zert into the ski pylon???

Jim@BAWS
07-14-2009, 04:36 PM
No need just remove the top allen head/bolt and pump until full!:D

The 84 PYLON does not have a SCREW OFF TOP...I can't believe you did not know that
Now I know something you do not know

The SCREW off top did not come out till 1989.

Did you know that MasterCraft makes TIRES and LAWNMOWERS and ocilating fans?

Jim@BAWS

Hoosier Bob
07-14-2009, 08:49 PM
Crap! I am an idiot! I will send all posts to yourself for precheck! Thanks Jimmy! So the pre 89 had the zerk fitting in the base at the mount?:D

PS Is that oscillating fan a 3 or 4 blade and if it comes with an OJ I am in!

PSS No threads die they just fade away!The 84 PYLON does not have a SCREW OFF TOP...I can't believe you did not know that
Now I know something you do not know

The SCREW off top did not come out till 1989.

Did you know that MasterCraft makes TIRES and LAWNMOWERS and ocilating fans?

Jim@BAWS