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    OK I give up! Where can I buy a good starter made in the US?

    My old starters finally gave up and I went on Ebay and bought one. The average price is very good and the quality is uniformly poor. The shafts are soft steel and one actually bent instead of the clutch protecting it. The second the Bendix sticks down after starting. I miss my old starters! The...
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    CDI to CDM force 90 Sport Jet

    OK I finally got my 90 HP three cylinder sport jet running properly after converting from CDI to CDM ignition. It has been quite a journey. While the CDI trigger coil will happily fire the CDM modules there are issues to be taken care of. Back in the 90's Mercury sold a kit to upgrade from the...
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    Observations on Timing, CDM conversion, Triggers and starting

    OK Settle in for a read. When I first got my Hobie Sport Jet 90 hp Force I had problems setting it up getting the timing at idle and WOT right and the throttle and WOT on the carbs correct. I started with the stock CDI system (really the whole engine stock) and had numerous problems, I wanted...
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    Bias circuit for change from CDI to CDM?

    I have been trying to figure out the bias circuit used in the CDM ignition to be able to replace the switchboxes on a "Mercury" Force 90 hp engine. I have been on the Force forum here, but I haven been able to get the information yet. The idea is to replace the switch boxes and individual coils...
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    Wanted --- Bad late model CDM trigger assembly---

    With regard to 3, 4, or 5 cylinder trigger for the Force/Mercury CDM engines. I need to dig out the bias circuit to be able to make an external bias circuit to upgrade the CDI to the CDM modules. I have looked all over for the internal circuit without success. The CDM modules are cheap on eBay...
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    Need opinion on Sport Jet 90

    The other day we went out in our freshly overhauled Hobie Jet Skiff with the Force 90 engine. We started out and the engine ran really well. We fished for a while and while running ~ 4500 rpm or so we noticed a little blubber but nothing alarming. We ran up to 5000 rpm (full throttle to see if...
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    Force/Mercury Frankenstein

    IF we are talking about a pre-CDM Force that you installed them on and have the early flywheel and trigger then there may be an issue on the bias circuit. This is the CDM parts I was referring to. The picture that you posted is of the Force / Mercury earlier CDI system. I had thought you were...
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    Converting from CDI to CDM ignition

    Thanks for the reply, Jerry. It seems that there is a compensation circuit built in the 1996-2000 trigger coil that is not in the earlier units as the newer one cannot be resistance tested. I think that the signal conditioning circuit does the bias compensation within the unit where the older...
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    Converting from CDI to CDM ignition

    OK I confess I have created a *astard ignition motor going from a CDI with switchboxes to late mercury CDM modules for (maybe ) improved reliability. I have a couple of issues, however and maybe someone can help me out. First the CDM modules are readily available on Ebay as is the three cylinder...
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    1995 Force (Sport Jet) ignition timing jitter?

    When I check the timing of the 90 hp Force engine I find that I have a few degees of jitter in the spark on all cylinders. Is this normal? Previously I had a lot of jitter and poor timing and pulled the flywheel and found pieces of magnet from a bad flywheel magnet that came loose and self...
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    Auto Blend system for Force 90 in Hobie Sport Jet?

    OK I know all about the "Auto Blow" reputation, but I have a reason I want to run by you guys. The reason I want a mixing system is that the boat provides a fuel storage tank that is recycled fairly regularly and would stay relatively fresh for emergency use, Having 15 gallons of unmixed fuel...
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    Sport Jet 90 rebuild

    SO with a strange noise emanating from the top of my 90 hp sport jet at idle I worried that there might be a bearing goind bad. So I had bought a donor jet boat for a couple of hundred dollars for the rebuildable engine and the jet parts that fit from the 93 to the 95 on the Hobie Jet Skiff I...
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    Stainless Plus Aluminum + salt water = Stuck bolts.

    I am replacing the engine and the fuel tank in my Hobie Jet Skiff and this is a major project. I have built up a spare motor to replace one that ingested water due to an improper gasket at the base. The old motor runs, but is making a worrisone noise at the top of the engine. BUT that is not...
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    Sportjet90 electrical issue

    First check the timing at TDC to make sure that the flywheel key is not sheared, throwing the timing off. If the TDC is correct then if you have the ignition on so that the kill black with yellow is not grounded you should have spark. Do you have the black or the red stator (look under the...
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    New (old) Mercury (Force) 90 hp spare engine, how to best store for future use?

    I bought a Regal Rush (1994) with a 90 hp sport jet engine and pump for spares for my Hobie Jet Fisherman I am looking for the best advice on how to best preserve the engine in longtime storage. The engine has good compression, but I have not tried to start it since the ignition plate and parts...
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    90 Sport Jet Carb float question

    I have cleaned and set up the three carbs on my Sport Jet 90 and when I bought it it had plastic floats in the carbs that have no way I can see to adjust the level. They are all a little too low (or too high when held upside down). The plastic floats have plastic tangs that as far as I can see...
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    Spark advance, throttle and timing

    I have a 90 Hp Sport Jet that I have been working on finding an fixing water getting into the cylinders, ignition problems etc. My current question is on getting the tower adjusted, the idle, full throttle and timing. If I set the idle screw to 1/8" like it shown in the manual I cannot get full...
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    How does the Force/Merc Sport Jet 90 fuel system hook up and how does it work

    I have a sport jet 90 that has a few problems and I wanted to verify how the fuel recirc system works and how it hooks up. My question is about the top cylinder to the manifold. The picture shows the bottom two going to the the corresponding cylinders while the top one shows going to a fitting...
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