a new jet ski jet boat project

[PSG-1]

new engine showed up it is wow clean oem pistons good crank just finishing the re seal for insurance purposes and I have a couple questions, it has v force reeds and ocean pro flame arrestors, I have 135 jets in the carbs but it is an oe size 105 120 135 are the oe options, i do not know if this is jetted fat enough anyone ever run these aftermarket parts and know about what jet size is in the ballpark for this engine?

The jetting should be about 105 for the MAG side carb, 135 for the center, (as it runs hottest).....and then 120 for the PTO side carb. This is what I ran in my engine, and I used Pro-K flame arrestors and carbon fiber reeds.



Yes, I had a lot of previous issues with the center piston having holes blown in it, going through several re-builds. The main problem that was causing this issue was the fact that I was letting other 'mechanics' work on my carbs, trusting that they were doing it correctly.

Once I decided to add carburetors to my list of things I'm able to work on....my detonation issues disappeared. The deto. issue was likely caused by the previous jackass mechanic who had a 155 in the mag, a 105 in the center, and a 135 at the PTO carb. No wonder it was blowing pistons!

Once I ran with the 105, 135, 120 setup, I had no more problems.

The final time the engine died was not because of detonation, but because a 31 foot para-sailing boat threw a 3 foot wake that nearly sank my boat, the engine ingested water, and had catastrophic failure.

So, I would run with what you have, again, do a 'throttle chop' at WOT, then pull the plugs and inspect them, to dial in the jetting. Perhaps go ahead and adjust the high speed screw out by 1/4 turn, so you know it's rich enough, then fine tune it.

Also, make sure that the oil injection pump is correctly synchronized, or you'll have a lean condition.

With the throttle at idle, the hash mark on the housing should line up with the line of the idle setting on the pump actuator arm. At the WOT setting, the hash mark should line up with the high speed mark on the actuator arm. If not, you'll need to adjust the jam nuts of the cable housing where it fits the bracket of the oil pump.

I got rid of most of my Tigershark parts, but I think I may have a few carb jets in the drawer of the toolbox, not sure what sizes they are, but I know there's a few high speed jets, and a few pilot jets.

 

[scubapro820]

hey that helps a lot I never invested in a manual I would have been confused I think it will be fat enough at 135 145 115 with 77.5 idle jets

 

[PSG-1]

I did have a manual, but, like an idiot, when I put the 4 stroke in my boat, I figured I wouldn't need a tigershark manual anymore, and threw it away. #-o If I still had it, I'd donate it to you.

But.... I'm quite familiar with the TS900 and TS1000 engines, everything except for rebuilding it, so, any questions you have, I might be able to help you out.

I do remember that the low speed jets were 78.5, for all 3 carbs, if that helps.

 

[scubapro820]

Yea mine are all 77.5

 

[PSG-1]

Also, check the internal filter on each carb, make sure they're clean.

If you get into dealing with pop-off pressure calibration, the correct pop-off pressure is about 21 PSI if you're running open stacks.

I will dig through my toolbox and see what parts I have left over for the Tigershark. They're yours if you need 'em. I'll let you know what I find.

 

[scubapro820]

I can't tell you how much I appreciate all your help. I go to so called pwc mechanics and they are no help . Most of the techs I work with don't know what a plug chop is lol .

 

[PSG-1]

I can't tell you how much I appreciate all your help. I go to so called pwc mechanics and they are no help . Most of the techs I work with don't know what a plug chop is lol .

Most people don't understand that a plug chop is about the only way to get a true reading of what's really going on with the high speed jetting. And a lot of PWC mechanics aren't going to go out of their way to help, they want you to bring it to them, and wait 3 months for them to fix it, and pay top dollar for it.

As for the extra parts, all I had was an 85 jet, a fuel filter, and the little black bellows piece that goes on the fitting on the back of the magneto housing.

I reckon when I got rid of the tigershark and all the parts, I got rid of ALL the parts. Could have sworn I had more jets and other small TS parts in the toolbox. (Guess it's time to organize it some, since I can't remember what's in the dang thing LOL)

Wish I had more parts, or the manual. But I can still offer my knowledge about that engine.

As for the plugs, the manual calls for a NGK BR9ES. You can also run BR9EYA plugs, but I always ran what the manual called for. Hope this helps.

 

[scubapro820]

Success ! 34mph 4 ppl fuel and beer . 1100lbs gross

 

[PSG-1]

Success ! 34mph 4 ppl fuel and beer . 1100lbs gross

=D> 8) Outstanding! Glad to see you got 'er running.

 

[River Rider]

Man looks to be running great. Put up some more pictures of the complete rig. I would llike to see the finished product.

 

[scubapro820]

I will take more and better pics soon but I have these now.

 

[River Rider]

Awesome. Bet it gets cozy.

 

[PSG-1]

Wow, it really looks good cleaned up and painted! I bet that cabin is warm during the winter, too.

 

[scubapro820]

It is very cozy and noisy, so im still working on reducing engine speed, Tthe tigerhark engine red line is like 7000 and i think 65-6700 is ideal for cruise. I was thinking i wanted the concord 16/21 pitch solas but its back ordered. kinda troubling bc 35mph 6500 rpm 1/2 -2/3 throttle fully loaded this leaves me to believe there is much to be had for power so now i have to find a way to get my power to the water!

 

[PSG-1]

It is very cozy and noisy, so im still working on reducing engine speed,

I think you meant to say engine 'noise' not speed....LOL. To reduce the noise levels, you definitely need a cowling, and you should line it with some egg crate foam, this will cut down on the sound a lot.

Tthe tigerhark engine red line is like 7000 and i think 65-6700 is ideal for cruise.

For the TS900, I think redline is about 7200, for the 1000 it's about 6900 RPM, if I remember correctly. On my boat, I have been running a Concord 13/19 swirl impeller, (YD-CD-13/19) and when I had the TS1000 engine, I ran most of the time at about 5500-6000 RPM for cruising speed. With the high output, I tend to run about 7000-8000 for cruising speed (why the higher RPM? we'll get to that in a minute).

I was thinking i wanted the concord 16/21 pitch solas but its back ordered. kinda troubling bc 35mph 6500 rpm 1/2 -2/3 throttle fully loaded this leaves me to believe there is much to be had for power so now i have to find a way to get my power to the water!

Keep me posted on that 16/21 pitch...I've been considering having my prop re-pitched to that spec., because, I have the same issue going on with my boat (top speed). The XL1200 pump I'm using is a 155mm pump. I forget what size the XL800 is, I'm thinking it's 155mm, but it may be a 144mm. If it is a 155mm, like my pump, then the performance of our two pumps should be similar.

My TS1000 engine had a redline of about 6900 RPM, and the boat ran about 42 MPH. When I switched to the High Output, I was expecting to see a dramatic increase in top end, but was surprised to see that the top speed was about the same as before, maybe about 3-4 MPH faster. Granted, the 4 stroke is more reliable, but I was perplexed by the issue of top speed. After all... the engine turns 10,000 RPM at WOT, so, I should be haulin' ***, right?

Well, if the PROP was turning 10 grand, I would be flying, no doubt about it. BUT, the MR-1 engine uses a 1.47:1 reduction gear, and this steps impeller speed down from 10K, to about 6,800 RPM, actually a slower prop speed than the TS1000!

Now, I know if you try to over-prop an engine, it will put too much load on it. But with a 4 cylinder 4 stroke engine, I believe there is enough torque to be able to turn a higher pitch prop, with no ill effects. The boat has more than enough hole shot, so, I'm thinking of re-pitching the prop from a 13/19 to a 16/21, perhaps even higher, I need to talk to a tech at impros and see if they have any ideas. In the meantime, though, if you get a chance to run with the 16/21, let me know how it works out.

 

[scubapro820]

Well I have my impeller coming soon 16/21 swirl skat trak. I took the boat out Sunday and there were 35 mph winds heavy chop I mean heavy 12" or so the boat took a beating. I.found several things I need.to change fuel filter location for better servicability and several new fuel lines and a service hatch. I got a random miss at opperating speeds seems to be a flat.out miss no knock or ping going to check the reeds over however anyway. The pistons and plugs are beautiful . I was however wondering about the fuel system design I have the mikuni carbs and I wanted a.fuel pump rebuild kit, but that is not listed or shown on parts diagrams its a mikuni 3 out pulse pump to the carbs its located on the engine plate near the starter is this an oe config?

 

[PSG-1]

Yes, that's an OE design, having the fuel pump mounted to the engine plate.

Your fuel pump should be a pentagonal-shaped pump, with 1 inlet, 3 outlets, and a pulser line.

Try this part number: DF 62-702 You might see a picture of a fuel pump that only has two outlets instead of 3, but they both use the same diaphragms and check valves. I've rebuilt a few of these.

As far as the high speed miss.....make sure that you have the CDI mounted in a manner that leaves some slack for the wires. I had this problem with my boat, had the CDI mounted a little too far back, and it had the rear plug wire pulled tight, where it would run like crap at idle, then it would occasionally straighten out at high speed, then go back to running like a POS at idle. Took me forever to figure out the obvious, the connection of spark plug wire to the boot was being interrupted from engine vibration, etc. I moved the CDI up a few inches closer to the engine, and that problem went away.

 

[scubapro820]

I'll check on that the spark plug wires, in the meantime Im thinking about getting a water temp guage for the engine temp a pressure guage for the pump nozzel and water supply inlet a vacuum guage for the intake grate side and possibly a preheated wideband o2 system . I was looking at some of the knock indicator setups as well I could connect one per cylinder but I have not found an inexpensive system for that

 

[PSG-1]

I'll check on that the spark plug wires, in the meantime Im thinking about getting a water temp guage for the engine temp a pressure guage for the pump nozzel and water supply inlet a vacuum guage for the intake grate side and possibly a preheated wideband o2 system . I was looking at some of the knock indicator setups as well I could connect one per cylinder but I have not found an inexpensive system for that

As far as the temp guage, I tried that with my boat, had it hooked into a T fitting on the discharge side of the cooling line, it wouldn't even register a reading. Then I made a threaded fitting out of aluminum, and welded it to the top rear end of the head pipe, the part right before the exhaust hose hooks up. This method worked pretty good.

HOWEVER, a temp guage will only show a problem AFTER you begin to run hot, which is really not the best method, IMHO. Instead of the temp guage, just go with a pressure guage, it's much better.

The pressure guage is better, because, THE VERY SECOND THAT WATER STOPS FLOWING TO THE ENGINE, the pressure guage says "hey, there's a problem, no water flow" As opposed to the temp guage, which is only going to start rising after the engine begins to overheat....ooops, that's a cooked head gasket, or in the case of the Tigershark engines, a cooked set of cylinder head O-rings, either way, a PITA. Also, with the pressure guage, you're not having to constantly watch the indicator streams coming from the cooling system, you just glance down at the guage for an instant analysis of the cooling system's condition.


For the water pressure guage, get one of those Teleflex outboard motor water pressure guages, they are 2" in diameter. Put a T fitting on the cooling line going to the engine. if you are using a water strainer, put the T on the engine side of the strainer, not on the pump side. If you put it on the pump side of the strainer, when the strainer clogs, it will not show a loss of water pressure. Run the pitot tube from the fitting on the T, to the water pressure guage at the console. When you are running, it probably won't read any PSI at idle. At about 3 or 4 grand, you should have about 5 PSI, and at around 6 grand, you should be at 10 PSI or a little more.

A vacuum gauge probably isn't necessary, unless you want one just for giggles. As far as the other stuff, kinda like the vacuum gauge, it's a matter of personal preference.

But if you could only put one guage in your boat, I would definitely advise you to install a water pressure guage.... and if you don't already have an inline water strainer, install one of these, too, it will save your engine. Jabsco makes an inline strainer with 1/2" barb fittings, a removable clear plastic cap so you can easily see any trash in there, and it has a removable screen.

I consider the pressure guage/water strainer an 'engine saver'...and a vital combination of equipment. The one time I ran my jetboat hard aground out here in the inlet, I crossed a sandbar, trying to give some fishermen a wide berth.... and the boat actually stuck on the sandbar for just a second, with me slamming into the console pretty good. I saw the pressure guage instantly drop to 0, and when I saw that, I immediately shut 'er down. Sure enough, when I opened the cap, the strainer was jammed full of a mud/sand mixture. I turned the engine over, and hit the throttle quickly a few times, until water blasted the sand out of the strainer, then I shut the engine back off, finished cleaning out the strainer, put the cap back on, and continued on my merry way.

Now, without those 2 items, this is the likely scenario: I would have crossed the bar, with my attention focused on getting across the bar, not watching indicator streams. If the engine had a temp guage, it would have gone to overheat, and the CDI would have kicked into the fail-safe mode when it overheated. Maybe it would be OK, but then again, we're talking about engines with aluminum blocks, overheat one of these, and it's likely to warp something, causing catastrophic damage further down the road. Also, without the strainer, the cooling lines and water jackets of the engine would have been plugged full of sand and mud. How do you get that sand out without a reverse-flow flush (garden hose to the fitting?) Pretty much impossible.

Again, a strainer and a pressure guage are the two things you should add to your boat. True, you might not be running in mud and sand like I do, but if you're operating on a river, in the spring and fall, you're going to encounter leaves and other debris on the surface, at some point, you will have an issue with that trying to clog the cooling system.

 

[scubapro820]

I do have the inline filter on my boat, it came with the tigershark I bought to start the boat project. Im going to install a pressure gauge soon as well as some of the things I previously listed. Got my skat trak swirl 16 21 installed today. I modified my nozzel by removing the shunt that was the ventri style syphon bilge I also cleaned and polished the hull holy smokes there was a lot of sheisse to remove from the 50+ years the hull has been around. I hope to gain some speed off the modifications and hull polishing. I have some b4 and after pics of the hulls appearance