Seadoo Speedster 240 EFI Excessive smoke at Idle - Multiple fixes applied already

[02PSU]

First off, I would like to thank everyone on this forum as I have done a ton of trial and error after reading the available posts/threads on this exact topic. I have a 2001 seadoo speedster with 240 EFI. The oil tank is on the port side of the engine if that helps determine which engine version we are talking about. I have spent a ton of time getting my boat perfect and am a bit obsessive with making it perfect (I've attached a pic to give you an idea). Just some of the upgrades in addition to cleaning/buffing the boat to within an inch of its life are the stereo, amp, tower, rack, and speakers. The issue that I am having is that the boat smokes excessively at startup as well as once idling for a while. When I take off after this idling period, the engine is clearly loaded up with oil and hesitates a bit before clearing out the oil in a puff of smoke and finally taking off. If I don't idle for long before accelerating, the boat takes right off and goes. After coming down in rpm (from above 3k), the boat will run clean for a few minutes before going back to the loaded up smoky state. I am aware that two stroke boats smoke, but this is way too much and completely embarrassing (I have been in other mercury EFI two stroke boats, including another seadoo with the same engine, but different hull - none smoke nearly this badly). Before anyone asks, these tests have all been done under load (in the water, not on hose). The boat runs gps verified 52mph and I just rebuilt the jet drive this season (stainless wear ring by impros and reconditioned prop that was already in excellent condition). I have owned the boat for three years and this problem has been consistent throughout the following attempts at correcting the issue:

-replaced port side temp 13536A14 twice with thermal paste (thought there may have been a chance I was sent a bad one).
-replace spark plugs each year with bpz8hs-10 (I have heard I should try BUZ8H or champion ql77jc4 - is that correct?)
-replaced all three fuel filters
-running quicksilver premium plus two stroke oil
-had mercury dealer in NY (alex's marine plus) inspect boat, recommend replacement of oil pump. replaced pump at cost of $350 and another $350 of labor with no change). Also confirmed the pump setting was on the correct mark

The only other symptom of the boat (it generally runs very well otherwise) is that it can be a bit difficult to re-start once warm. Once cooled off (or fan run) for a few minutes it starts right back up. Not sure if this was related but figured it may be relevant. The last thing I haven't checked is the TPS, and it seems that from some discussions that may the culprit. I just became a premium member on here so that I can look up the manual and instructions on checking it (I'm not great with electrical although I'm a solid backyard mechanic). Any tips/pointers on other things that could be contributing to the issue? Thanks in advance everyone!

Thomas

 

[Dr Honda]

Since you have a 2001 boat... I wouldn't 'think you would have a Gen2 engine (they were 2001-1/2 production, and didn't show up in Seadoo boats until mid 2002 MY boats) But to verify... your oil tank is low, and on the side? Not toward the top and hanging just by the flywheel? Posting a pic will be the fastest way to verify.

Well... as a typical shop... their answer was to just throw $$$ at the problem and hope for the best. (This is why I hate shops) These pumps NEVER fail, unless there was some other issue. (physical damage, wrong stuff pumped though it... so on) And they should know that if they have ever worked on Seadoo, or Mercury. So... since we already can't trust them... stick your head under the deck lid, and see if the mark on the pump arm lines up with the mark on the body, with the throttle at idle.

Anyway... as you know... yes... it's a 2-stroke, and it will smoke. Mine will smoke like it's throwing a "James Bond" smoke screen when I first fire it up. Yesterday, I put mine in the water, and started it to go to the dock. I looked over, and a family was looking at me like they thought my boat was going to blow up. Once at the dock... I actually told them... it's a big 2-stroke, and takes a few minutes to clear out. (Most people just assume it's a 4-stroke since it's an inboard) Anyway... Once going... It will clear out. After sitting... or after a long idle, I will start to smoke again, but it's not heavy. Mostly a wispy, fog kind of smoke. There are a bunch of places around Pittsburgh that have long no wake zones... so it can come back. But I find if I can just crack the throttle, it will really reduce the smoke. (Basically put a small load on the engine) So... I think our boats are running about the same. No... my smoke doesn't get heavy after it's warm... but I think it's a judgment call and would be hard to compare without seeing it. (could you post a vid of your idle smoke?)

As far as your pour in fuel injector cleaner.... well... to be blunt... it's useless. And, it's really not safe on a 2-stroke. Here's the deal... it's a solvent of some sort. That solvent can break down oils. Your engine is relying on a very thin layer of oil to keep it alive. (see where I'm going with this?) in a 4-stroke... the fuel and oil are separate... but it still doesn't clean the injectors. But on that note... if you think it's running rich, the injectors could benefit from a proper cleaning/servicing. It will probably address the hard re-start issue.

One the note of hard-restart... yes, replacing the Port side temp sender will help... but only if it was bad. Before replacing parts... just check them. It's a simple test with a meter. Now, the TPS is also tied to that. Since the boat is running well... I don't think it's bad... but it could be adjusted improperly. In the manual, it outlines the procedure to set the idle point.

On the sparkplug comment... just run the spec plug. Use NGK. They seem to hold up to 2-stroke abuse better than any other brand. (This is coming from 40 years of playing with 2-strokes) FYI... the plugs in my boat just ran my engine for the 6th year yesterday. SO... if the engine is running properly... they will last.

And finally... oil. Over the years... I have noticed that some oils smoke less than others. But, some of that is subjective, and I have never changed oils and had a magic change. (From lots of smoke, to no smoke) I'm currently using Pennzoil XLF. It's a semi synth, and seems to minimize smoke. When I first rebuilt my boat, I had another national brand... and it was very smokey. Quicksilver is supposed to be a good oil.

 

[02PSU]

Thanks for the info Dr Honda. Yes, I would say that it is smoking too much - I will get a video this weekend when I am out on the water. Also, as for the cracking of the throttle, that really doesn't help the issue. Even if I cruise through a no wake zone at 2200-2300 rpm it will still be smoking. But the worst is definitely idle/neutral. Good to know on the plugs that I have the right ones in. The plume of smoke after idling for a couple minutes and taking off is also disheartening, especially after the boat is running at full temp... I will also be double checking the mark on the newly installed pump as soon as I arrive at my home where the boat is located this Friday. I will also upload a pic of the oil tank location. Quick question - have you checked your TPS on your boat for functionality? It seems that there are a few others on the forum that have had issues consistent with ours regarding amount of smoke and that the TPS is most likely the culprit assuming the port temp sensor is operational (which it is). I am planning to check the TPS this weekend with a volt/ohm meter and a couple of sewing needles to tap into the wires. Is there anything else I might need? any idea on how long that should take? I also saw a posting that said to spray some contact cleaner around the tps and move it around as the connection can be poor, which I will try as well unless corrected.
Thanks again,
Thomas

 

[Dr Honda]

Yes... I have checked my TPS, and have a new(ish) port side temps sender. To me... the amount of smoke I have is normal for a big 2-stroke. But, from your new description... it sounds like you have a lot more idle smoke than I do. If I bring my throttle up to 2000 RPM, and pushes me to 8~10 mph... my smoke is totally gone.

As far as squirting some contact cleaner around the TPS... that won't do a thing. It's a sealed, potted unit. Also... I've cut a few bad ones open, and what I found is... It's not a dirty pot... its physically warn out.

And finally... since we are talking about an oil pump with an arm... it has to be a Gen1 engine. The newer, Gen2 engine has an electric oil pump, and it's controlled by the ECU. (no linkage on it)

 

[02PSU]

Ah, thanks for the clarification on the engine version. And funny I know I cant trust it at all, but my speedo only shows 4-5mph at 2k rpm (I know this means nothing). Was I correct on the procedure of testing the unit? "I am planning to check the TPS this weekend with a volt/ohm meter and a couple of sewing needles to tap into the wires. Is there anything else I might need? any idea on how long that should take?" Also, I know that i need to unplug the bullet connectors on the port temp sensor, but is there anything else that needs to be disconnected in order to run the test? Thanks again for the speedy replies. I DEFINITELY don't want to consider going pre-mix, especially as that probably wont make the smoke issue any better...

 

[Dr Honda]

I always plan an hour for simple things... if you need to plan. The test itself is quick, (A few minutes) but it's not super easy to get to. AND... sometimes you just have to crawl in and out of the engine compartment a few times because you forgot something. AND... getting everything together, and cleaning up after take time. So... yep... an hour.

You have the procedure down right. Disconnect the temp sender... poke the wires... read the voltage at idle, and full. (Key on) As I recall... you are looking for 0.2 to 0.3 volts in the idle position... and 7.5 volts at full throttle. Since you do have some noticeable smoke... you may want to push it down closer to the 0.2 volt range.

 

[Tim75]

Too much smoke? Check injector pressure. I went thru this with 65psi, instead of 35psi. After i got that under control, smoke is minimal, as Dr. H says. Had injectors serviced, too.

 

[02PSU]

Hey Tim, how do you check injector pressure? And how would you correct it if it’s off? Is that something that is fixed by having the injectors serviced? And do you know the cost associated with servicing injectors/a reputable company that does that?

Thanks,
Thomas

 

[02PSU]

Also, am I missing something in the manual section or is there nothing for the 2000 and 2001 mercury motors (shop manual)? I only see the 2002..

 

[Tim75]

Merc manuals are for a range of serial numbers. You should have the book that covers your engine s/n.

Pressure- best option is a fuel injection pressure gage. About $50 local. There is a valve on top of the vst (looks like a tire valve). Key on engine off- should be 36psi. Key off- should slowly drop. If pressure is too high, (mine was 65psi) the regulator needs to be replaced. $300+ from Merc. I put an after market reg. on mine. If too low, could be bad pump or dirty stuck injectors leaking. They can be serviced, usually about $20 each, + shipping. You should be able to find a local shop. I have heard the name Brocato recommended. I used HavocSpeed.com. They were tested, logged, disassembled, cleaned, tested again and returned in 24 hours. Runs great!

 

[02PSU]

Checked the throttle position sensor... perfectly within range. Going to check the fuel pressure next, just ordered a gauge. Dumb question, where is the VST? Just took a quick peek in the engine compartment and couldn't find the valve. Also, going to have the injectors serviced at the end of the season because I'm really running out of ideas here.

 

[Dr Honda]

Also, am I missing something in the manual section or is there nothing for the 2000 and 2001 mercury motors (shop manual)? I only see the 2002..

Someone else was having issues with that. I guess they got rearranged over the years. I went in and fixed the labels. Just look for the manual for the "Gen1" engine.

 

[Dr Honda]

Checked the throttle position sensor... perfectly within range. Going to check the fuel pressure next, just ordered a gauge. Dumb question, where is the VST? Just took a quick peek in the engine compartment and couldn't find the valve. Also, going to have the injectors serviced at the end of the season because I'm really running out of ideas here.

The VST is the aluminum tank on the front, top of the engine. your second oil tank sits above it. If you look on the Port side of the engine, on top of that aluminum tank... you will see some hoses connected to a regulator. The valve should be just in front of that.

With that said... can you post a vid of your smoke? I have a feeling you are chasing something that may be normal.

****EDIT****

I'm supposed to go fishing with a buddy on Wed. I will try to remember to vid my smoke. but please vid yours so we can compare.

 

[02PSU]

Thanks for the info and update of the manuals. I completely forgot the video this weekend as I was a bit pressed for time when I got the boat in the water. I’ll have time to take one this upcoming weekend. Also, is there any truth to this running Seafoam through the engine thing? Or just another useless liquid fix? Wish I knew how many hours were on this beast..

 

[Dr Honda]

Seafoam is BAD on a 2 stoke... and I don't care who says otherwise. Here's the deal...... A 2-stoke only lives because of a small film of oil, that is transported through the engine via the fuel. Seafoam is a solvent !! that solvent will displace and/or break down that oil to "Clean" the system. In doing so... it will rip up the engine !!!!!!!!! THe only thing that goes into the tank, other than fuel, is a good stabilizer. I use it at every fill up to keep the alcohol fuels from separating, and to pass water.

OK... will it kill your engine with one use? Probably not. But there are guys who use it all the time, and have short engine lives. It's fine in a 4-stroke, where the oil is pumped around, and is separate from the fuel system. But even then... if you have injectors than need cleaned... just have it done right.

You can get the HR's of the engine... but it takes a DDT or Rinda tool to read the computer. If you have a local dealer that isn't a rip off... and you ask during the off season... they may read it out for you. I'm sure if you ask them now... they will charge you 1/2 hr labor.

 

[02PSU]

Thanks for the heads up on the seafoam, I definitely wont be using it. Also, the SN off my engine is OE387171

 

[switt]

I had excessive smoke in my 97 Challenger 787 Motors. Found oil leaking from case. Pulled engine and resealed case. All good now.

 

[Dr Honda]

Hi, I don't mean to highjack any threads .......................

Then don't. You obviously know that it shouldn't be done. So, please start your own, and we can help. Trying to answer multiple questions convolutes the thread.

 

[Dr Honda]

I had excessive smoke in my 97 Challenger 787 Motors. Found oil leaking from case. Pulled engine and resealed case. All good now.

The 800 engine has oil in the center. The Merc doesn't.

 

[02PSU]

So I have now checked the compression (130 across all cylinders) as well as confirmed that the TPS is operating exactly within the specified range, as well as smoothly. My marina is threatening to kick me out the smoke is so bad. As I said, the longer I am at or near idle the worse it gets. Even cruising at 2k or 2500 rpms it doesn't clear up. Only at around 4k or above. Otherwise the boat runs great and does 60 on the dreamometer. What's next? I really don't want to have to give up on this thing and sell it. The only two things I haven't done are to check the fuel pressure and service the injectors (does anyone have a write up on how to remove them)?

thanks

 

[Dr Honda]

Did you check the pump alignment? There's a mark on the oil pump arm, and it should line up with the mark on the pump body when at idle. If the link popped off... it could just be at full oil.

 

[02PSU]

I believe that its correct, but just in case I will take a picture this upcoming weekend and post it. Anything else I can check in the meantime? Also, does anyone have a breakdown of how to remove the injectors? Is it a big job?

 

[Dr Honda]

It's not a big job... but it's a pain in the butt. On your boat it's not as bad as mine. They are inside the plenum... so the back of that needs to come off. Once inside, you will see the fuel rail, and the injectors. Unfortunatly... I don't think there is a write-up on it... but since you have the manual, you can see the parts explosion.

 

[02PSU]

Continuing on this thread now that summer is back. Still no fix. Most recently a new boat mechanic tried rebuilding my fuel pump and replacing the diaphragm?... 2.5 hours of labor including their test run. Again, before this I and the mechanic confirmed that oil pump is at correct hash mark. I have already personally: tested good compression across all cylinders (126-130), new oil pump, both temp sensors replaced, new plugs, all fuel filters changed, correct quicksilver oil always, tps sensor tested for consistent increase and range, but still can't get it. The also connected it to the computer and there are no codes. I'm going to try posting a video now so you folks can tell me if this is normal for you. Only thing I haven't checked are the injectors.

What's happening: when I start it I get a plume of smoke -- enough to clear out a boat launch and very embarrassing. Idling more than a minute or two begins producing thicker and thicker smoke. This can only be cleared out by bringing rpm over 3500 and clearing it out. The longer you idle, the worse the acceleration is when you do punch it (while it clears out all the oil). Runs great wide open 50mph gps no problem. Also after you take it down off of cruising speed it idles clean for the first minute or so. Any other ideas would be GREATLY appreciated.
Thanks

 

[02PSU]

anyone? to those of you who have a 240, can you confirm that this smoke is not normal? I really would appreciate any help - thanks again