$75 each INCLUDING shipping via USPS. I have two of them. Same unit in standard and counter-rotating engines. Assembly part # is 805185A36 [new #] or 90747A3 [old #]. Assembly is used, but cap, rotor and wires are nearly new, less than 10 hours. Last year I replaced Thunderbolt-IV ignition...
A good rebuild will give you a better starter than most of those available new these days. If you want more help than that, please post the exact engine information.
If you have a bad Thunderbolt-IV module, bite the bullet and install a new ignition system rather than replace the bad module. Here is why:
1) COST- a new T-bolt-IV module, if you can find one, is going to be north of $300, if you can find it. A used one is...USED; how long is it going to last...
Mercruiser T-bolt ignition distrib sensor wires
I had a bad Thunderbolt-IV module, so I replaced the ignition system in both engines. These parts came from a 1987 Mercruiser 454 Bluewater inboard. Parts available are:
2 sets of Distributors with caps and rotors, Mercruiser part #805185A36-...
Neither had I, until last Sunday. There is now one on a boat lift across the creek from my marina. Looks to be of 1970's vintage, about 20-22 feet, with an i/o. I saw a 1970's Sea Ray center console about 5 years ago, but never saw a walkaround.
Trying to help a friend fix his 330 generator
Coolant boils out past the pressure cap. Cap has been replaced, thermostat and impeller replaced, and it has very strong raw water flow. The only other thing I can think of is a head gasket leak allowing exhaust gases to pressurize the antifreeze...
That 429 lb-ft of torque comes at 3800 rpm. Not a good replacement of a big heavy boat with lots of windage. Your most effective and cost-effective repower options [in this order] are 1) a pair of new 454's with fuel injection [if you can find a pair], or a pair of 496's or 502's.
It is installed exactly like old-style flax packing. Use the cork-screw tool to remove all the old stuff. Clean the shaft and gland out with clean rags and acetone. Cut the packing at an angle, not at 90 degrees. Stagger the pieces 180 degrees so that the ends of each piece are on the opposite...