'94 48spl surging. PROBLEM SOLVED!!

[ElGuapo]

So I am running across the lake and BAM! I have a big loss of power and the motor starts surging...BAD! I back off the throttle and it stops...throttle up and it starts surging again.

OK, I have eliminated what I thought to be the obvious.

carbs completely rebuilt
replaced ALL fuel lines including main line from tank and primer bulb
tank vents nicely
new plugs
swapped coil
swapped plug wires
I have spark
compression is 150 on each cyl

It is still surging

any ideas? power pack maybe? this is extremely frustrating.

 

[tashasdaddy]

Re: '95 48spl surging. HELP!

Re: '95 48spl surging. HELP!

i have had more than one motor surge, because the outer part of this bushing breaks and falls out.

 

[ElGuapo]

Re: '95 48spl surging. HELP!

Re: '95 48spl surging. HELP!

i just ran out and looked. I have two of these motors and that bushing looked the same. I'm not sure if it is right or not though. It doesn't look like the one in your picture. Mine are black. We are talking about the one with the red markings over it right?

 

[tashasdaddy]

Re: '95 48spl surging. HELP!

Re: '95 48spl surging. HELP!

correct some are white some black. the bushing has 2 parts, and inner and outer, the outer cracks and falls out. they are held on by an tiny oring,and washer.

 

[ElGuapo]

Re: '95 48spl surging. HELP!

Re: '95 48spl surging. HELP!

yey, mine do not look as thick as that one so I am probably just looking at the inner part. I'll look into that, but it is not what is causing my surging

 

[tashasdaddy]

Re: '95 48spl surging. HELP!

Re: '95 48spl surging. HELP!

it allows play in the throttle linkage, thus the throttle plates move, could be fuel pump not keeping up. what it sounds like is when there is a fuel restriction, the pump can't keep up.

 

[ElGuapo]

Re: '95 48spl surging. HELP!

Re: '95 48spl surging. HELP!

it allows play in the throttle linkage, thus the throttle plates move, could be fuel pump not keeping up. what it sounds like is when there is a fuel restriction, the pump can't keep up.

I'll change that bushing for sure, but it'll surge if I move the linkage on the cabs by hand.

I'll swap out the fuel pump this morning from the one on my other parts motor....hopefully it is good.

thanks for your help.

 

[tashasdaddy]

Re: '95 48spl surging. HELP!

Re: '95 48spl surging. HELP!

just moving the carb linkage, without out moving the complete throttle linkage, is not correct. as you are not increasing spark with the added fuel/air mixture. the link n sinc, has to be correct for the spark and fuel/air to work together.

 

[ElGuapo]

Re: '95 48spl surging. HELP!

Re: '95 48spl surging. HELP!

just moving the carb linkage, without out moving the complete throttle linkage, is not correct. as you are not increasing spark with the added fuel/air mixture. the link n sinc, has to be correct for the spark and fuel/air to work together.

ahh. gotcha

 

[ElGuapo]

Re: '95 48spl surging. HELP!

Re: '95 48spl surging. HELP!

OK, PROBLEM SOLVED!!! Whew! THAT was a doozie. I definitely learned a lot about this motor in the process.

So, I pulled the fuel pump off and compared it to the one on my older parts motor. My fuel pump was missing parts inside! I robbed the missing parts(springs, plastic pads and gasket) from my parts motor, installed them and it started up and ran fine. Awesome right? Nope.

I took it out to the lake to run it. I take off from the dock and I'm up on plane no problems. Everything is great! I get about 1/2 mile from the launch and bam! Serious surging again! UHG!

So now I am thinking this HAS to be heat related. This motor pisses water like a mule so I figure the water pump is ok. Maybe that overheat sensor is bad. I pull the wire and what do you know? The damn thing runs perfectly. So I run it a couple of minutes and shut it off so I can put the cowling back on. When I shut it off I hear some gurgling from inside the motor. Oh crap! Maybe that sensor wasn't bad and the water flow is being restricted by a sticky thermostat?

I creep back over to the launch and pull the thermostat. Look what I found.

Gross. Packed full of ANTS! All of this Carp was caused by dam ANTS!

Anyway, new thermostat should be in today at 2. Hopefully that will solve everything.

 

[HybridMX6]

Re: '95 48spl surging. HELP!

Re: '95 48spl surging. HELP!

You may want to try to flush whatever you can out of there while it's open, instead of passing whatever is in there through the engine and possibly causing another blockage somewhere that is harder to get to.

 

[tashasdaddy]

Re: '95 48spl surging. HELP!

Re: '95 48spl surging. HELP!

i agree, you can, flush front and back from the stat opening. put muffs on it, start the motor, and let the water pump push out what is left in the water tube, the take the water hose and flush the head.

 

[ElGuapo]

Re: '95 48spl surging. HELP!

Re: '95 48spl surging. HELP!

You may want to try to flush whatever you can out of there while it's open, instead of passing whatever is in there through the engine and possibly causing another blockage somewhere that is harder to get to.

Oh yey, I did that at the lake. I just backed it back down the ramp into the water and flushed it out for a few minutes.

thanks guys. i'm ready to go fishin now!

 

[tx1961whaler]

Re: '94 48spl surging. PROBLEM SOLVED!!

That's as bad as mud daubers in the carb. I learned to keep the choke plate closed when stored after that one........

 

[ElGuapo]

Re: '94 48spl surging. PROBLEM SOLVED!!

That's as bad as mud daubers in the carb. I learned to keep the choke plate closed when stored after that one........

yey, I imagine they could clog a few jets.