1997 GS won’t start after carb rebuild

[Wil6gl]

This ran last Sunday. I bought it off a guy, it idled like crap and took a second after giving it throttle then took off. So I figured carb rebuild. Ordered Mikuni kit, rebuilt went to put it in then ski was slow cranking. The guy had said he just but a battery in it but I went and got a new one, cranks great. Won’t start. I am getting fuel through the lines but my pulse is spitting out a greyish mixture back into the pump. Facebook said leaky crank seals, won’t even fire with starting fluid or gas down the plug holes. I disconnected oil line to see if maybe it was leaking down in there and flooding with oil.

 

[burtshaver2021]

Check your compression first, check for spark, where did you buy the rebuild kit and what all came with the kit?. Read over @mikidymac carb rebuild thread to see if you might have missed anything while rebuilding it. Vacuum check your fuel filter and fuel selector valve for leaks.

 

[tobytd]

The liquid behind the pump diaphragm came out of the crank case. It won’t pump fuel WITH liquid in there.

 

[seadoosnipe]

You never mention your pop off pressure. When you get a kit, it should come with 3 different sets of springs. If the pop off pressure is too high, you’ll likely not open needle valves to flow fuel. Too low, you’ll flood the engine with fuel. The procedure for testing it is in the manual. I may have an old thread on doing it too. I don’t visit the forum all the time, but the 787cc is the only one I rebuild.

 

[seadoosnipe]

The liquid behind the pump diaphragm came out of the crank case. It won’t pump fuel without liquid in there.

I’m sorry, but no. The area on the pulse line side, should be dry. Maybe a bit of residue, but no oil. The pulse line is a reciprocal pressure, from the stroke of the piston, pushing back and forth, for the diaphragm to pump fuel. If you’re seeing a greyish color, I’d ask if your ski still has the grey tempo lines. If so, they must be replaced. They gel from the inside, causing blockage.

 

[burtshaver2021]

The greyish sludge your seeing in the pulse line could very well be an oil water mix from leaking inner seals. I have a 95XP with leaking inner seals. At the beginning of each season I always take the plugs out, ground the plug wires and crank it over a few times in case oil has leaked past during the off season, with the 95XP I’m always good for the rest of the season and actually this year barely anything came out but I do it with all my machines just as a precaution. If your able to get it running correctly just keep an eye on it; it may not be leaking badly at all, if it is you may be able to get some years of use with a valve installed in the oil line to the rotary valve cavity.

 

[Wil6gl]

You never mention your pop off pressure. When you get a kit, it should come with 3 different sets of springs. If the pop off pressure is too high, you’ll likely not open needle valves to flow fuel. Too low, you’ll flood the engine with fuel. The procedure for testing it is in the manual. I may have an old thread on doing it too. I don’t visit the forum all the time, but the 787cc is the only one I rebuild.

I skipped it because I used the spring that was already in there. But I’ll take it back off and check it.

 

[Wil6gl]

Check your compression first, check for spark, where did you buy the rebuild kit and what all came with the kit?. Read over @mikidymac carb rebuild thread to see if you might have missed anything while rebuilding it. Vacuum check your fuel filter and fuel selector valve for leaks.

Compression is 145/150 I got it off eBay. Spark is good shocked my self once already.

 

[burtshaver2021]

Compression is 145/150 I got it off eBay. Spark is good shocked my self once already.

You’re 2/3 of the way there then. Make sure that’s a genuine mikuni kit, they are made to sound authentic sometimes when they are not.

 

[Wil6gl]

The greyish sludge your seeing in the pulse line could very well be an oil water mix from leaking inner seals. I have a 95XP with leaking inner seals. At the beginning of each season I always take the plugs out, ground the plug wires and crank it over a few times in case oil has leaked past during the off season, with the 95XP I’m always good for the rest of the season and actually this year barely anything came out but I do it with all my machines just as a precaution. If your able to get it running correctly just keep an eye on it; it may not be leaking badly at all, if it is you may be able to get some years of use with a valve installed in the oil line to the rotary valve cavity.

 

[Wil6gl]

So when I took the plugs out and turned it over, I got a bunch of white smoke coming out of one of the cylinders in spurts. I added a picture here, but it doesn’t show up very well. I took a video of it too.

 

[burtshaver2021]

So when I took the plugs out and turned it over, I got a bunch of white smoke coming out of one of the cylinders in spurts. I added a picture here, but it doesn’t show up very well. I took a video of it too.

Did you get it to run? Was that shortly after it ran? Normally white smoke is from burning or vaporizing water. You could test the cooling system for leaks. The procedure is in the manual. Do you see any signs that it ingested water? Even if the cooling system was leaking, that shouldn’t stop you from starting it on the trailer. Seems like you have all the ingredients for it to run except for fuel/air. Odd that it won’t run with a little pre mix in the plug holes. You should probably pre mix a tank of fuel for it, till you have everything up and running correctly, Also don’t mix brands of 2T oil.

 

[Wil6gl]

Did you get it to run? Was that shortly after it ran? Normally white smoke is from burning or vaporizing water. You could test the cooling system for leaks. The procedure is in the manual. Do you see any signs that it ingested water? Even if the cooling system was leaking, that shouldn’t stop you from starting it on the trailer. Seems like you have all the ingredients for it to run except for fuel/air. Odd that it won’t run with a little pre mix in the plug holes. You should probably pre mix a tank of fuel for it, till you have everything up and running correctly, Also don’t mix brands of 2T oil.

Man, I feel like such a newbie and I guess that’s because I am. So I pulled the carb back out and when I was going to try and do the pop off test, I realize I didn’t even have the spring in. So I put the spring in and it runs now, but I’m really boggy From idle and I have to hold full throttle it revs up really hard and then it will takeoff. Is that an adjustment screw issue?

 

[burtshaver2021]

Man, I feel like such a newbie and I guess that’s because I am. So I pulled the carb back out and when I was going to try and do the pop off test, I realize I didn’t even have the spring in. So I put the spring in and it runs now, but I’m really boggy From idle and I have to hold full throttle it revs up really hard and then it will takeoff. Is that an adjustment screw issue?

Take your time and read through @mikidymac csrb rebuild thread. The only thing to as to his thread is to turn the low speed screw back in 1 turn when cleaning the low speed circuit by spraying carb cleaner in where the low speed jet goes. I find those holes get over looked when cleaning and it won’t run with them being dirty. Don’t run it on the trailer any more than 30 seconds without letting it sit for a half hour in between. Set the high and low to factory specs available at Seadoosource.com

 

[1997SeadooGTI]

Check your compression first, check for spark, where did you buy the rebuild kit and what all came with the kit?. Read over @mikidymac carb rebuild thread to see if you might have missed anything while rebuilding it. Vacuum check your fuel filter and fuel selector valve for leaks.

Thank you. I just ordered a compression tester to check it. Not sure what it should be because I've seen both 135 & 150 as being correct. Do you know what it should be?

 

[1997SeadooGTI]

You never mention your pop off pressure. When you get a kit, it should come with 3 different sets of springs. If the pop off pressure is too high, you’ll likely not open needle valves to flow fuel. Too low, you’ll flood the engine with fuel. The procedure for testing it is in the manual. I may have an old thread on doing it too. I don’t visit the forum all the time, but the 787cc is the only one I rebuild.

35

 

[1997SeadooGTI]

The liquid behind the pump diaphragm came out of the crank case. It won’t pump fuel WITH liquid in there.

Thank you. Removing the spark plugs & cranking the engine was going to be my next step. How did the fuel get into the crank case? I want to make sure I fix the problem from reoccuring.

 

[burtshaver2021]

Thank you. I just ordered a compression tester to check it. Not sure what it should be because I've seen both 135 & 150 as being correct. Do you know what it should be?

150 is perfect on that motor, 120 is time for a top end rebuild. They should also be within 5 percent of each other