Test Wheel Needed???

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Boilermaker

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I want to check the timing on my 1978 115HP Johnny> <br />My Clymer manual recommends a "384933 test wheel". How much can I expect to pay for this test wheel at my local Johnson Parts counter (I assume thats where I get it).<br />Can I just keep the prop on the engine & run it up to full throttle while the boat is still on my trailer at the ramp??? Or do I need the test wheel to get the revs up??? <br />Also, is my helm mounted TELEFLEX tach accurate for tuning??? It was installed new, last year. If not>>>what is a good, but inexpensive tach to use for tuning??? <br />Thanks for any help! :cool:
 

REELSPORT

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Re: Test Wheel Needed???

I hear tell that test wheels are pricey, Backing<br />your boat down the ramp and reving up while on the trailer You might not get the rpms that you need. What you might want to do is a search I understand Joe Reeves has a method that does not involve a test wheel or high rpms to get the timing real close.
 

Silvertip

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Sep 22, 2003
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Re: Test Wheel Needed???

Reving the engine on the trailer will not only allow the engine to easily reach max RPM (and more), those RPM may be spread all over your driveway in the form of engine pieces. There is no load on the engine when the prop is pushing air -- the test prop provides that load without pushing the boat (in the water). Your owners manual and nearly every service manual constantly warn about reving higher than 2500 RPM when using muffs. Test wheels can be found on E-bay (rarely) but I have seen them. New they are cost prohibitive for the amount of time you use them.
 

WillyBWright

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Re: Test Wheel Needed???

Mr. Obvious says, "Have somebody drive the boat while you flash the flywheel." Done that many times, but it can be dangerous with an open flywheel and you bouncing along in a moving boat. :eek:
 

REELSPORT

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Re: Test Wheel Needed???

willybwright is right. You can have somebody drive the boat for you while you check the timing<br />but be very careful. I also read somewhere here in the forum that you could cut down an old prop to make a test wheel out of it and then back it down the ramp and check it. I think you know that I do not advocate running high rpms while on muffs unless you are just tired of your motor.
 

Boilermaker

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Re: Test Wheel Needed???

OK>>Thanks Guys! <br />I don't know where you got the idea that I wanted to run the engine up on ears in the driveway??? Read the post again>>>"...Can I just keep the prop on the engine & run it up to full throttle while the boat is still on my trailer at the ramp??? "<<<<br />I really can't do the flashing while running at 40 mph across the bay here>>>I'm to old to be climing on the engine well & flyin' off the back while my 12 year old son laughs it up.<br /><br />I am under the impression that the older V4s didn't have any rpm requirement for the timing, only that it gets the timing arm fully advanced. My manual states that it just needs WOT>>><br />HOW ABOUT IT>>>ANY EXPERTS KNOW FOR SURE????<br /><br /><br />Thanks again<br /> :cool:
 

Nos4r2

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Re: Test Wheel Needed???

If this is any help... try emailing the ebay UK shop Suffolk_systems-user Id pc_marine_tech.<br />He had a load of test wheels for sale a while ago that didn't sell(not sure if he had one for your engine tho) and may ship to you.
 

mar t G

Seaman Apprentice
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Jun 28, 2004
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Re: Test Wheel Needed???

just a thought. if it's dangerous. and it is. i can just see me and my wife daredevelin it across the lake now. NOT and the price which seams to be rather expensive.(OR IS IT)wouldn't it be safer and cheaper to just bring it to someone who has a test wheel say your local mechanic?<br />just 2cents <br />mar t
 

Dhadley

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Re: Test Wheel Needed???

Its real simple. And it does indeed need to be done on the older outboards to make sure the timing is correct. <br /><br />Just back the trailer down the ramp far enough that the AV plate is just under the water. Start the motor and put it in gear. Slowly bring the rpm's up. If it doesnt reach 5000+ then pull the trailer up slightly. If it vents too much, back 'er down a bit. The first time you do it, you may be moving the trailer a couple of times.<br /><br />Once you establish that the r's are where you want them, check the timing as someone slowly brings up the r's in gear. <br /><br />Its no big deal and only takes a minute once you get the hang of it.
 

NOSLEEP

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Re: Test Wheel Needed???

You can adjust the full spark advance without<br />having the engine running.<br /><br />Take the plugs out and have the throttle at full,<br />set that timer base under the flywheel tight<br />against the rubber stop on the end of the full<br />spark timer advance stop screw. ( wire it against<br />the stop if necessary.)<br />rig a spark tester and have the spark gap set at<br />7/16". hook up the timing light to the #1 plug wire.<br />Crank the engine over and set the spark advance <br />to<br /> 4 deg less than what the engine calls for.<br /> The reason for the 4 deg difference is that when<br />the engine is actually running,due to the nature<br />of the solid state ignition components, the engine<br />gains the extra 4 deg.
 

Basscat 1

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Feb 11, 2005
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Re: Test Wheel Needed???

Also make sure your battery is fully charged first.<br />The above mentioned method is known as the "Joe Reeves method" on the board.<br />I like Dhadley's idea too. I have done it both ways.
 

Dhadley

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Re: Test Wheel Needed???

We also do it both ways. The static method is dead on most of the time but we like to verify under a load. 9 times out of 10 we dont have to readjust when verifying.
 

NOSLEEP

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Re: Test Wheel Needed???

Basscat 1 you are correct.<br />Most everything I didn't know but needed to about<br />boats, I learned here at iboats.<br />This static method Joe Reeves posted many times to<br />help out the fellow boater. Guys like him and<br />Dhadley help make us all better boaters.
 

Boilermaker

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Re: Test Wheel Needed???

Do the older x-flow V4 engines still advance the timing the aprox 4* from the static (Joe Reeves) method???<br />WHAT RPM SHOULD I SET THE TIMING AT???>>>my book just states ...engine running at WOT.<br /> <br /> I mainly want to verify that the timing is set correctly. I had a shop do a "tune-up" on the engine last year, but I found a few other problems with things that I feel should have been picked up by the shop (loose fuel line at the carbs leaking into engine pan & just not what I would call CLEAN workmenship).<br /><br />Last season I felt the engine was down on low end grunt. Although this is an "old" engine>>>it sat in storage for 23 years and only has about 350 hours on it at most. <br />Carbs were rebuilt, timer base was freed up from solidified white greese,and plugs were changed. The shop told me that the compression was very good>> "like the engine was just broken in". <br /><br />My only complaint is that I feel I should be getting a few more revs out of it. <br />The boat is a 1971 WestWind 180 (17.5Ft x 7.5ft max beam) Modified Vee runabout(no flotation foam).>RPMS@WOT=5300 with the engine trimmed very high . Prop is a STILETTO 21317 (17"pitch).<br />I know that common thinking here is that the rpm should be higher, but its in Johnsons range of 5000-5500 RPM. My biggest complaint is that the holeshot really stinks with this prop. When I was in my late teens, this boat/engine combo would pull me up on one ski with the factory aluminum 19 pitch prop, & I'm a large guy.>>>Now it takes a LONG time just to plane, even with just me on board. I don't have the boat here yet>>its still in winter storage, but I plan to work on it over this weekend (Memorialday wkend. Maybe raise the X-factor...its on the lowest setting now.<br /> SORRY THIS WAS SO LONG!!! :rolleyes: <br />THANKS FOR ALL HELP!!!<br />Jim :cool:
 

wilde1j

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Re: Test Wheel Needed???

Boilermaker, the Joe Reeves method is with the engine NOT RUNNING, so forget the manual you have.
 

Boilermaker

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Re: Test Wheel Needed???

Thanks WildeOne<br />I ment to say >>what RPM should I run at to check the timing as is traditionally done!<br />Altough I find the "Joe Reeves" method intreging, I still would like to verify the timing advance as prescibed by the factory.
 

Boilermaker

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Re: Test Wheel Needed???

Anyone? Lowest RPM to set timing, the traditional way???<br /> :cool:
 

MarkHPCA

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Re: Test Wheel Needed???

I am not sure but I believe that you rev it, on the test wheel or equivalent, to about 4500-5000 RPM.
 
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