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    Looking for replacement heat exchanger

    Bring the current/broken heat exchanger to a local radiator repair shop. They ought to be able to repair it or find something as a suitable replacement
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    2006 DP-SM with Clicking Under Load

    Worn o-rings on the dd will cause this
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    Mercruiser 357 question

    If the engine/alpha package is closed cooled oem then there are two raw water pumps. One mounted on the engine (inboard/bravo style) and one in the drive (alpha style)
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    Question about 90 amp fuse on starter

    The 90/100 amp fusible link/fuse is in place on newer oem mercruiser engines to protect the internal regulator/rectifier in the alternator in case of accidental reversed polarity when connecting the battery This came about when many boat owners installing batteries reversed polarity and blew...
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    Alpha 1 Gen 2 Drive shaft housing oil seal compatibility.

    I've used gasket sealer on the top cap bolt threads without fail for years along with the recommended o ring seating area between the cap and housing. Others use grease and that's fine, the main point being it is ime better than installing the bolts dry As far as the seals in question you can...
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    MerCruiser 3.0 MPI Electrical Short

    Proper testing for a short to ground is with an ohm meter. Locate a solid ground and test circuits that are not supposed to have ground. Once you find the circuit that is grounded you can disconnect components to see when the ground goes away. This is a static/unloaded test. A proper wiring...
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    Pinion gear timing to driven gears in B3 upper housing

    Being off a tooth won't affect anything. Just make sure after the drive gear/u joint bearing assembly is installed and before you install the rear cover the gearset rotates smooth and the +/- lines are offset and as close as can be to even with the marks on the housing after the entire assembly...
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    Alpha 1 Gen 2 Upper Swivel Shaft Pin

    When a .010" feeler gauge fits snug between the lower swivel portion of the gimbal ring and gimbal housing and the u bolt is still loose at the top of the ring, turn the ring side to side and briskly strike the exposed portion of the gimbal ring downward with a deadblow hammer. This will seat...
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    Pinion gear timing to driven gears in B3 upper housing

    That chart is for the gear case (lower/propshaft) retainer/carrier. OP is reassembling the driveshaft housing (upper). The retainer wrench/tool in question has a handle, approx length is 12 inches center to center
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    Pinion gear timing to driven gears in B3 upper housing

    With the rear cover of the driveshaft housing removed you will see the shift linkage, shift shaft and yoke assembly along with the brass shift races on both gears. The brass races are offset to ensure proper shifting and smooth/balanced operation of the driveshaft, clutch and gearset under a...
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    Oil Analysis for high-hour 4.5L 250 HP

    They did Mercury, or Brunswick/someone in the family bought GM's foundry in Mexico along with the rights/specs/proprietary info for the 4.3, 5.7, and 7.4L engines Dunno the specifics of the deal but possibly an agreement is mercury cannot "reissue" any of these engines or the epa won't allow...
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    330 black scorpion low power

    The short lived MEFI controlled small blocks mercury used for mie did not utilize the neutral safety switch as an additional "in gear" switch to control rpm in neutral. That wasn't introduced until the 555 series ecm was used and in such case would set a fault along with an audio alarm warning...
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    330 black scorpion low power

    Posting test results as "ok" and "appears normal" doesn't tell us very much. If you removed and inspected all 8 injectors and observed the spray pattern that again doesn't say much as a dirty injector spray pattern can appear visually good but still lack proper flow There is a service...
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    1986 Mercruiser 470/170hp/3.7L Carb backfire, low vacuum, other weird issues

    The ignition system for this model(s) mcm engines has always been battery supplied voltage conventional/points from the factory. The only task the stator/flywheel/balancer/regulator system has is to provide ample charging/maintainence for the battery That said, this thread is long but the focus...
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    Bravo 3 loss of lube oil - slowly then rapidly x2

    Could be gear lube monitor system fittings, hose, o ring at the bell housing or seal(s) in the drive Boat needs to come out of the water to inspect properly
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    Harmonic balancer installation MerCruiser 3.0.

    Regardless of it being on all the way the balancer is junk. Hub looks destroyed on one side and appears to have been beat on a few times
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    Need RPM’s on 383MPI 1970 SeaRay 24’ project

    Possibly, mercruiser has used smartcraft/vesselview for the better part of 20 years. It should at least indicate a fault but may or may not give detailed information depending on the model/style/age of the vesselview. You have an ecm that is mapped/programmed for a stock 5.7/350 on a 6.3/383...
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    Click No Start

    Picture in post #7 shows the yel/red wire connected to the wrong primary post at the starter solenoid Yel/red needs attached to the inside (closer to block) post
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    MEFI 3 diacom capabilities

    Possible but not probable to test for spark with diagnostic equipment on a mercury mefi system. Capabilities are quite limited as the original DDT was used for onboard diagnostics when the engine was new The ignition sensor is used for the mefi ecm to read engine rpm as well as control...
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    454 7.4L mystery fasteners on back of engine block

    Rear engine mount bolt Yes, due to the spacer If it's tight, it's tight You should tie the sender wires out of the way as not to interfere with the steering actuator nor rub on the coupler
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