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View Full Version : Continued issues w/ engine cutting off ('83 S&S)


Lake Watagua VOL
10-27-2006, 10:05 AM
I have been refurbishing a 1983 Mastercraft S&S. All has been going as planned and the boat, after the following replacements: alternator, belts, starter, plugs, wires, ignition switch, fuel filter / water separator, all was running well this summer at the lake. She was purring like a 71 GTO (w/ a Ford engine off course). Unfortunately, at the tail end of the season she started to stall herself out at high speeds and RPMs. My first thought was this was a fuel flow issue. So, I replaced the fuel filter and then the pump. This did not make a difference. Whenever the engine would run for 10 mins or so and the RPMS hit 3-4K, the boat would stall out. I would be able to restart it and it would run for a while then the same @ high RPMS. Recently, I took the boat out of the water for the winter and noticed it stalling out at any RPM over 1.5K. I can only think two things: the fuel line that goes into the tank has a mesh screen on the end and maybe it has silt or residue in the tank blocking the flow of fuel or the thermostat is bad and it is tricking the engine into quitting, preventing an overheating incident. However, the temp gauge is registering OK. Can the thermostat be bad and the temp sensor still read accurately? Or more concerning the carb be screwed up? I am not real sure how carbs work but when the boat was running I could only see fuel dripping from the front two barrels of the Holly carb. The rear facing barrels looked almost rusted a bit, as if not activity had been occurring it them.

H20skeefreek
10-27-2006, 02:04 PM
I'd probably bet that you need a carb rebuild. BUT, start at the tank. Pull the pickup and make sure there is not blockage, then check the anti-siphon valve if you have one, then make sure there is no blockage in the line anywhere by blowing air through it. If those things check out, and you've already replace the filter and pump, (check the screen you mentioned too), then you should have the carb rebuilt. Depending on the condition of the carb, you may want to replace it. When I had mine rebuilt (same problems) it didn't fix the problem, then I realized that my mechanic had cracked the OLD fuel bowl, and fixed it with JB weld. I took it to a guy that works for PCM and he said, that with a carb that old, he'd replace it. So I did, and now she runs great (after more problems this year with the fuel pump).

M-Funf
10-27-2006, 02:14 PM
It may be helpful to add a fuel pressure gauge near the carb to see if you've got pressure under running conditions. If fuel is cutting out, the pressure will drop...which could indicate a blockage, or bad pump/filter (which you've already replaced...).

If you've got good fuel pressure, then it's probably time to check the carburetor...

Good Luck!

Lake Watagua VOL
10-27-2006, 03:20 PM
thanks ... i've got a buddy who'll rebuild the carb for free, classic car mechanic. hopefully, it is in good enough shape to rebuild. The issue w/ the screen in the tank is that to pull out the intake line, i need to remove the tank b/c of clearance. not a great engineering job there ... but the wake is flat as wood ... so i guess the engineers spent there brain power where it mattered most.

H20skeefreek
10-27-2006, 03:53 PM
You don't have to remove the tank on my '85 to get to the pickup.

east tx skier
10-27-2006, 03:55 PM
There's also a screen on the fuel line where it connects to the carb. You might go ahead and give the flame arrestor a good cleaning, too. Couldn't hurt. Good luck.

amber 6
10-27-2006, 07:23 PM
Did it rev out when not in gear and only cut off when engaged in gear.

MMCCAR12
10-30-2006, 06:33 PM
Have you checked the dwell. Maybe your points closed up after being run for the season. How old is the cap, condenser and rotor. Its always something.

Lake Watagua VOL
11-01-2006, 06:23 PM
did not rev out. actually would cut off slowly (true stall) when at between 2.5K and 3K. then gradulaly, over 2 to three more trips out, work it down to stalling at 1.5 - 2K RPMS.

Thanks

Lake Watagua VOL
11-01-2006, 06:24 PM
would this allow for it restart w/ ease after each stall? i am getting REALLY confused by this. it seems like it could be a really easy fix. just trying to deternine the root cause is a bit$h. too many options!

thanks

Lake Watagua VOL
11-01-2006, 06:26 PM
i do not have enough clearance between the top of the tank (where the line enters) and the top of the hull. only have about 3 ins and the tube going into the tank is at least 9-12in. seems as if i am doing something wrong here. the 83 and the 85 should not have that much of variance in tanks and hulls.

thanks

H20skeefreek
11-01-2006, 08:06 PM
my pickup is flexible. after you get it loose, you just pull it out.