www.iFourWinns.com

According to the specs in the VP Owners manuals (available for free download on their website), the early GXi engines used to use 0.045" ( 1.12mm) like the GSi engines of the same ere, but different plugs to the GSi..

Later small blocks engines up to at least 2004 use a different type of plug again; Long life plugs (but then they all used the same type, as did the the 4.3). The gap for those is 0.060" (1.52mm). The later plugs, VP part no 3861632 were AC 41-932 from the GM factory, VP replacment ones are Champion RS12 PYP.

Graham

I just managed to find my owners manual and it states 45 thou,which has been highlighted in pen ,so Im guessing it was done by the dealer or original owner,My guess is that the combination of the plug wires showing resistance and the plug gap being too large is stopping the engine from revving out correctly ,all makes sense really ,I have new ngks to fit today along with the new plug wires ,so Im confident that will fix the issue ,In fact im so sure that I made a 20 dollar bet with my friend! lol do you think im on the right track or about to lose my 20 bucks?? will let you know the findings soon ,cheers ,Mike

Anything from .040 to .045 will be perfect. Stick with NGK plugs, if you're feeling frisky get the iridium ones and never change them again. Standard copper plugs (AC Delco, Champion, etc) should be changed every season.

If the plug wires showed a high resistance and the gap was big, you could have been blowing spark out and it basically making itself a "rev limiter"

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1981 Columbia 8.7
2015 Yamaha FZR - 87mph - sold
2006 Yamaha GP1300R - sold
2003 Chaparral 215 SSI - sold
2009 Stingray 195CS - sold
2000 Four Winns H180 - sold
1976 O'day Daysailer II - sold
Rick's Four Winns H180 Mods/Upgrade Thread

Well Im about screwed for ideas now! I took the boat out for what was expected to be the big day when she would open up correctly with the revs,unfortunatly the same problem persists,I had new ngk plugs fitted today and set a 45 thou and new mallory spark plug wires and also the timing checked yet again,I just cant understand what the problem is,Im not a trained mechanic but have a fairly good knowledge in general of mechanics,I feel ive touched on almost everything possible,to re-cap ,compression checked out fine,timing -correct,new plugs and wires(all set correctly) flame arrester checked and cleaned,distributer cap checked over for cracks or damage-all fine,new thermostat-old one was faulty and engine wasnt reaching correct operating temp-now correct,manifolds and risers replaced less than 12 months ago,so no issues with restriction-all fine,motor has only done around 260 hours and runs as sweet as can be,no misfiring or hard starting ,smoke ,rattles or other sounds or anything to suggest there is any problems,the only thing is she will still not rev over 4000-4200 rpms no matter what the conditions or load,I have tried everything I can think of,the last resort is to accept defeat and take her to the volvo agent and have a diagnostic check carried out and hope like mad it shows up a fault of somekind that I can remedy

You wrote " it revs out correctly while on the hose with no load , but in the water theres just no way"; that rules out the tacho.

When it's on the hose, the engine is under no load, it doesn't need full throttle to reach maximum RPM and it doesn't use as much fuel at max RPM as when it's running the boat in the water at maximum RPM. With everything else having been checked and remedied/ found OK, if it isn't reaching maximum RPM it tends now to point to a fuelling issue; too little fuel availability (the knock sensors will prevent a weak mixture from potentially damaging the engine so may in effect be restricting RPM). It could be restriction caused by the fuel filter(s), lines from the tank to the filter/ pump module (including the tank outlet which incorporates a check valve which can become restricted by debris), the fuel tank vent ( allowing air in as fuel is taken out) and if all these check out OK, then the fuel pumps. The 2 pumps being expensive to replace if it's not them so better to eliminate the other factors first !

Have you any chance to run the fuel to the filter/ pump module from a remote tank?

Graham

thanks Graham ,sounds like a very good idea ,I think i will try a remote tank tomorrow after work and I will also check the filters ,although they should be ok as they were only changed 3 months ago ,but you are right ,it needs to checked and eliminated! and also the anti siphon valve/pick up pipe,I guess if it solvrs the problem on a remote fuel tank ,the answer must be the valve/pick up ? honestly, im pulling out the remaining hair i have left! will keep you posted on how t goes tomorrow ,thanks for your advise,cheers ,Mike

Mike,

Yes, if a remote tank solves it, the problem is for sure somewhere in the things you've bypassed.

Graham

Sorry but i did not look on your specs....is your engine carb or injected....possible that carb needs to be re-jetted for your altitude if boat was set up for different alt....or.....something could be happening with the efi that is causing wrong fuel to air mix....just a thought, cuz my first bet was on the prop.

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http://i1339.photobucket.com/albums/o71 ... wqm355.jpg


08' H210SS
VP 5.7Gi

Are you sure the prop is not out of alignment, shape, our cupped incorrectly? If fuel isn't your issue, I'd look at your drive and propeller next. It may be marked as an **X** prop, but is it really?

Just a thought.

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2001 Horizon 260 - 7.4 Volvo GSI DP

Graham puts it better than I ever could! I mentioned before, change the fuel filter. The filter could be getting clogged. I don't know your engine, but on some it is a lot easier to bypass the tank than the filter & the tank. GOOD LUCK!!

This is a funny thread to follow. Keep it up, very entertaining and somewhat informative as well.

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One of 4 Previous (Sold) Boats:
2000 Four Winns 268 Vista

Current Boat: 2004 Chaparral 235 ssi cuddy

Well actually the tach could still be the problem. The tack does give some readings (4000 - 4200 RPMs). How do you know that's an accurate reading? On a hose you might read 5000rpms...but are you really revving it to 6000? The only way to know for sure is to use a computer, or another tach...Maybe I missed this amongst the thread, but are you getting normal speed reading from a GPS?

Not sure if you've found this yet, but punch in your engine serial # here to get the details such as year / model etc. on your engine

http://www.volvopenta.com/volvopenta/gl ... gines.aspx

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2002 Vista 248
"Sunny Dayz"

How bout we start a pool???? My money is going on a prop problem........

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2011 Four Winns H260 Frenzy $ea Note
VP 8.1GXi/DP EVC 420HP
2007 Silverado 1500 CrewCab 4x4
Previous:
2002 Four Winns H200
5.0GXI 270HP

I'm in!!

I didn't go back over the whole thread, but Cap'n Morgan did suggest reporting back what the maximum speed obtained at WOT would be by GPS. I would want to know how close you get to what Four Winns claims you should achieve for your model year of boat and engine/drive. Here is the data from the Four Winns web site for a 2001 268.

PERFORMANCE
Power HP / KW Propeller (Dia x Pitch) Type Top Speed Cruise Range
IN CM MPH KPH MI KM
5.7 GS/SX/250/187 151/2 x 15 39 x 38 AL 34-37 55-60 150 242
5.7 GS/DP/250/187 F4 F4 SST 37-40 60-64 160 258
5.7 GSi/DP/280/209 F4 F4 SST 39-42 63-68 170 274
5.7 GXi/DP/315/235 F4 F4 SST 40-43 64-69 160 258
8.1 Gi/DP/375/280 F4 F4 SST 43-46 69-74 160 258

Mike.

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Current Boat
- 2001 Four Winns 328 Vista "Hour Decision"
- 2010 310 Mercury Inflatable

Previous Boats
- 30' Doral Prestancia
- 25' Doral Citation