Muffler issues?

MikDee

MikDee

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To all those in the know, I have clean 96' Yamaha Waveventure 1100 that I've had for 3 yrs, it runs good, no problems, 150hrs now, but it doesn't seem to have as much speed, & power as it I think it should? It never did more then 48-50mph on the dreamometer with just me on it, no factory tach of course :( even tho I am kinda big, 250lbs. I was wondering if the muffler could be somewhat clogged up with carbon? Does this happen to jet ski's? I know that 2 cycle motors usually have an issue with this happening.

I also put 3 washers under the front of the rideplate a short while after I first got it, to bring the bow up.
 
Jeff Walkowiak

Jeff Walkowiak

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Re: Muffler issues?

my honest opinion is that you probably need to rebuild your carbs,, the internal filters get clogged and the diaphragms get old and worn out, you may also need to check the impeller and pump liner,, yes it should go faster than what you are describing
as for the muffler,, pour some common dish soap in to your flush hose,, run the engine on the hose while it washes out the soap from the muffler,, you will see a lot of black goo come out of the exhaust,, that is residual 2 stroke oil,, this is something you may want to do occasionally to keep the muffler cleaned out,, but I doubt the muffler is causing you issues,, a clogged muffler will usually cause you to burn the rear piston and hatch the engine
 
A

astro150

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Re: Muffler issues?

hi mikdee. 150 hrs you may need to rebuild the top end . check compression first.
 
liquidlew

liquidlew

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Re: Muffler issues?

I have a 96 1100 Venture with 135 hrs. and it runs as good or better than the day I got it. You shouldn't have any compression issues. Unless some fluke thing happened, Yamaha is the most reliable pwc on the water. You can check the compression yourself, it's easy. The 1100 should have 120 psi per cylinder. They don't all have to be the same, but they should all be within 10 psi of each other. My '96 701 Venture has 340 hrs. and the psi is supposed to be 150, I checked it last year and both cyls were 160, they went up! I have 3 Ventures, never had a single problem.
You should check your pump and impeller, sounds like weeds or your impeller digested some sand/rocks, both of those issues will make you loose thrust. You will have to crawl up underneath it with a flashlite and look up inside the pump, you will see 3 leading edges of the impeller, check those for deep nicks. Ideally they should be straight and clean. If it's not too bad you can take the grate off and get a small file up in there and file the nicks, if it's to beat up you should replace it or send it to Impros in Riverside CA, they refurbish impellers. And even a little grass or weeds can slow you down, last year my 95 wasn't reaching top speed it usually does and I reached my hand underneath the pump (not running of course) and felt nothing, but when I got it home and looked way up inside the pump, I had a small piece of long grass wrapped around the driveshaft in front of the impeller.
Also your fuel filters inside the carbs might need cleaning. But I have had no carb problems on mine and it's as old as yours so yours should be ok. Getting to the filters is easy but you have to remove all 3 carbs, so rebuilding them while they are out couldn't hurt. If you take off the carbs, it might be hard not to destroy the base gasket, or you have to get a new one before the carbs go back on.
 
liquidlew

liquidlew

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Re: Muffler issues?

Just looked at your pics, geez, how do you afford to run all those?:eek: You a Sea Ray guy too? Think I've seen you post on I/O forum. I put a Riva ride plate on all 3 of my Ventures, they help get it up on plane quicker but Riva don't make them anymore so it's eBay for old stuff like that! Yamahas rule!:D
 
MikDee

MikDee

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Re: Muffler issues?

liquidlew said:
Just looked at your pics, geez, how do you afford to run all those?:eek: You a Sea Ray guy too? Think I've seen you post on I/O forum. I put a Riva ride plate on all 3 of my Ventures, they help get it up on plane quicker but Riva don't make them anymore so it's eBay for old stuff like that! Yamahas rule!:D
Click to expand...

Well lew, Thanks for the help, all those boats are history now that I've moved to Pa. with it's lakes, I've left the Great South Bay on L.I. I just have my 19' Bayliner skiboat w/a 125hp Force, and my jetski.

Jeff, Thank you also, the last time I checked my jetski had about 115lbs compression, pretty even across the board, and I've tried adjusting the mixture screws thru their limited range with the plastic caps on them (no difference, that I can tell?) and it's all pretty clean, no weeds, or growth, on the lake I use, I haven't dewinterized it yet this year, but I will check the impeller then, and is there some type of wear ring to be checked there? I'd like to get a ride plate, but I guess it's prob. obsolete? I've changed the main fuel filter, but is there actually filters in the carbs themselves?
 
liquidlew

liquidlew

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Re: Muffler issues?

Yep, each carb has a little bucket fuel filter inside one side where the fuel line enters the carb. I just removed the rack of 3 carbs as a unit, layed it on the bench and removed the cover plates on the side, that's the pump side where the filsters are. Maybe the Mikuni website will have a diagram, I have a little Mikuni tuning guide that explains how to do all that and more. Not too hard to do on the twin carb, but the triple is thighter to get to. I had mine off 3 years ago to put a primer on, got primers and switched to premix on all 3 skis. If you watch eBay you will eventually find a ride plate, that's where I got mine, but they are getting fewer and far between. Riva, Protec, and Ocean Pro make them (or used to) for the Venture. I'm also planing to put a Solas impeller on the 1100, did it on my 701 and noticed much better giddyup and 200 rpm on the top end. So I would check those fuel filters, 12 yr old ski and if they have never been cleaned out, it's time anyway to check them.
 
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