benjilafouine
Well-Known Member
Which quantity fits in there? I have purchased the appropriate oil last year from BRP.
Benji.
Benji.
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Question about top speed
- Thread starter benjilafouine
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benjilafouine
Well-Known Member
I purchased the OEM oil from BRP (a very small bottle like 200 ml). I will read the manual to see how easy it is to change.
Benji.
Benji.
benjilafouine
Well-Known Member
I finally took my ski to a BRP dealer in Ontario (not the one who goofed up last year on my new engine installation) and they checked jet pump and changed oil. Everything was A-1, even the wear ring. They also checked the throttle cable and it was set correctly as well. So here is what's left to try to explain why the new engine is 4 mph slower than old engine:
Weight (including fuel): need to try it on an empty tank
Shaft not aligned perfectly????
Water Regulator: what is that and how can it influence speed???
Rotary valve not aligned perfectly?
Dealer says that a 4 mph variance is is definitely not a big thing. I would have like them to check timing but dealer would not take care of that since they do not want to maintain/fix 2-stroke engines anymore (they do not mind working on shafts and pumps).
Benji.
Weight (including fuel): need to try it on an empty tank
Shaft not aligned perfectly????
Water Regulator: what is that and how can it influence speed???
Rotary valve not aligned perfectly?
Dealer says that a 4 mph variance is is definitely not a big thing. I would have like them to check timing but dealer would not take care of that since they do not want to maintain/fix 2-stroke engines anymore (they do not mind working on shafts and pumps).
Benji.
1983
Well-Known Member
As stated before, if you didnt measure before on a GPS, and you arent now either then there is no true way to identify that you are in fact missing 4mph. The factory speedometers are not accurate nor consistent with age for that matter.
Go ride the ski this season and enjoy it.
Rob
Go ride the ski this season and enjoy it.
Rob
benjilafouine
Well-Known Member
So there is no way to know since it was not measured last year with a GPS and same for this year.
Benji.
Benji.
soccerdad
Well-Known Member
So the water regulator adjust how much water is sprayed into your exhaust system. If it is not working properly, you will not get top RPM. But your motor is a 717? if so, I don't know if you have a water regulator.... It sits on top of the water box at the end of the tuned pipe.
benjilafouine
Well-Known Member
Doesn't ring me a bell to me but I have the service manual in a PDF format. I will search it. The GTI LE 2003 is a very basic ski. They were the entry level skis in 2003. The lowest equipped models didn't even have instruments. At least I have the speedometer and fuel gauge.
If there is a water regulator, then its setup might have changed since I had the exhaust welded up last year as it was leaking at the point of entry of the water hose (but I didn't see any regulator there). I will take a few pics tomorrow.
Benji.
If there is a water regulator, then its setup might have changed since I had the exhaust welded up last year as it was leaking at the point of entry of the water hose (but I didn't see any regulator there). I will take a few pics tomorrow.
Benji.
benjilafouine
Well-Known Member
Went to pick up my ski this afternoon. Dealer said he was not able to read number of hours on the ski??? The other dealer could last year. How do you read the hours on a 2003 GTI LE anyway? They said they connected the ski to their diag tool (or whatever) and that number of hours didn't show up.
Benji.
Benji.
For the 80-100% throttle, There isn't much but there is a difference. Knowing RPM would definitely be helpful. Maybe worth investing in a tiny tach for the future. In my experience the difference is 6700- to slowly climbing up to 6950 rpm
The 2003 GTI LE base model means that it has a 717 engine not the 787. Which is why we have the confusion of having a water regulator or not. In this case we do not have one by design.
Using an older normal scantool you should be able to see the hours on it and even reset the maintenance hours to know how long you've been running the new engine. Maybe they were using something newer and more sophisticated that isn't backwards compatible? No idea there, but the older scanners could read up to 2003. At least it worked with last key I did on an 03.
The only things left that I think could cause a top speed or top end power decrease would be the compression or possibly engine to pump alignment or retarded ignition timing. ( I think having 145psi is a bit low for new or rebuilt. I tend to see 150-155 depending on attention to detail) I wonder if the squish is in spec or if the compression has in fact been lowered by the re-manufacturer. Did they use a thick 6 hole base gasket or size it up for what's needed. Whats in there for parts, OEM or aftermarket. Those are the things I wonder and question the overall build of the engine.
Another thing would be running lean on top end if the fuel pump couldn't keep up with demand or if there is a slight air leak in the fuel supply line. (I've only had one 717 engine do this 80-100% no change thing and it was the water seperator gasket leaking)
Try a plug chop at 80% and another at 100% with new plugs and See if there is a difference.
If the engine is performing to its max and the plugs are right, that could just mean its what that engine can produce.
Well that's all I can come up with.
The 2003 GTI LE base model means that it has a 717 engine not the 787. Which is why we have the confusion of having a water regulator or not. In this case we do not have one by design.
Using an older normal scantool you should be able to see the hours on it and even reset the maintenance hours to know how long you've been running the new engine. Maybe they were using something newer and more sophisticated that isn't backwards compatible? No idea there, but the older scanners could read up to 2003. At least it worked with last key I did on an 03.
The only things left that I think could cause a top speed or top end power decrease would be the compression or possibly engine to pump alignment or retarded ignition timing. ( I think having 145psi is a bit low for new or rebuilt. I tend to see 150-155 depending on attention to detail) I wonder if the squish is in spec or if the compression has in fact been lowered by the re-manufacturer. Did they use a thick 6 hole base gasket or size it up for what's needed. Whats in there for parts, OEM or aftermarket. Those are the things I wonder and question the overall build of the engine.
Another thing would be running lean on top end if the fuel pump couldn't keep up with demand or if there is a slight air leak in the fuel supply line. (I've only had one 717 engine do this 80-100% no change thing and it was the water seperator gasket leaking)
Try a plug chop at 80% and another at 100% with new plugs and See if there is a difference.
If the engine is performing to its max and the plugs are right, that could just mean its what that engine can produce.
Well that's all I can come up with.
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benjilafouine
Well-Known Member
[MENTION=64286]Mekanix[/MENTION]
Thanks for the info. I am leaning toward the timing that would not be top precise. As for compression, I think I got it like that as it was tested just after the burn-in period at about 20 hours.
Can you tell me what scantool I would need to monitor my ski by myself and how much it costs?
Thanks.
Benji.
Thanks for the info. I am leaning toward the timing that would not be top precise. As for compression, I think I got it like that as it was tested just after the burn-in period at about 20 hours.
Can you tell me what scantool I would need to monitor my ski by myself and how much it costs?
Thanks.
Benji.
I would think a can doo pro should be able to do that. All you need is the basic version which gives you a few licenses and i think they cost around 400$ with 4 licenses.
http://candoopro.com/mobile.php?sea-ski-atv-diagnostic-store,14
Ignition timing is set statically with two alignment marks when the stator is installed. That doesn't mean its good dynamically but its usually really close and its a pain in the but to change since you have to remove the flywheel each time. I've seen a few sheared woodruf keys cause retarded timing and affect top end but usually it messes with midrange as well.
You could check the squish as well. Just be carefull not to loose any solder in there. Check it at the mag and pto side of each piston (along the same axis as the wrist pin)
Expect 1-2 mm or 0.0040-0.0080" .
But if you find that its on the loose side, is it worth it to you to have to disassemble the engine to change a base gasket for that little extra top end?
benjilafouine
Well-Known Member
I understand what you are saying. I won't mess with it but I know for a fact that timing was adjusted "by eye" last year because the dealer didn't have the aligning tool in hand... This is why I suspect the timing to be not exactly dead on. As you pointed out, I won't mess with it only for 3-4 mph. And this is way out of my competencies.
Going for a ride!
Thanks.
Benji.
Going for a ride!
Thanks.
Benji.
There is no tool for setting the static ignition timing. Its just two marks that you align by eye when installing the stator between the stator plate and casing. For dynamic setting you need a dial indicator to locate top dead center and mark the pto. Then using a timing light you can see how close it is and tweak as necessary.
For the rotary valve timing. Its easy to get it right on after doing a few of them if you use an OEM seadoo valve.
WSM valves have been off a bit sometimes.
You can get the tool to set it properly or print one out on clear projector plastic and then cut it out to make your own, its not a hard thong to do. There is just lots of stuff in the way.
If it was off allot you would notice it. Im not sure how much being off by a few degrees would effect top end.
For the rotary valve timing. Its easy to get it right on after doing a few of them if you use an OEM seadoo valve.
WSM valves have been off a bit sometimes.
You can get the tool to set it properly or print one out on clear projector plastic and then cut it out to make your own, its not a hard thong to do. There is just lots of stuff in the way.
If it was off allot you would notice it. Im not sure how much being off by a few degrees would effect top end.
benjilafouine
Well-Known Member
Yeah, but as you pointed out, 3-4 mph is not enough to investigate further. It runs fine otherwise.
Benji.
Benji.
benjilafouine
Well-Known Member
I am null in mechanics... But bring me computers and servers (the huge ones) and no problem sir! I would almost bet that the timing is not 100% dead on. If I ever buy another ski, it will be a 4-tec.
Benji.
Benji.
benjilafouine
Well-Known Member
I am selling my house in the city and moving to the cottage by next year and then taking en early pre-retirement. Maybe I will have some time then. I know the "logics" behind it, just never put my hands in it. Don't even yet have a garage but this will be remedied in two months!
And I am also missing some tools. I have a fair bunch of them but still missing a nice mechanics kit.
Benji.
And I am also missing some tools. I have a fair bunch of them but still missing a nice mechanics kit.
Benji.
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