Scott, what does BMEP mean?
Max rpm for this MIE 330 is spec’d at 3800-4200 rpm in the service manual.
My WOT is 3850 rpm turning a 19x17 3-blade prop on the 2:1 V-drive.
The manual gives a min and max advance curve that gives the range for this engine.
Total spark advance minus initial...
My 26ft Tollycraft is running fine with the single Mark IV 454 on a 2:1 V-drive, but I’m wondering if I can improve performance by adjusting the advance curve on the distributor?
This is a 10,000 lb flybridge cruiser, 26’8” LWL, 10’ beam, runs at 7 knots at 1700 rpm most of the time, or 14...
This just started recently, rpms occasionally surging up/down 100 rpm at 2000 rpm slow cruise, occasional smell of gas in exhaust, especially when reducing throttle, engine sounds a little rough, not purring. Vacuum readings at 2000 rpm are rock steady. Quadrajet carb on a 454.
My inboard has closed cooling but the exhaust elbows are seawater cooled and need to be replaced every 4 years.
If I plumb a connection to my 40 gal water tank I could easily rinse them with freshwater after every trip.
Besides the expense of doing this properly with bronze fittings etc, plus...
So I have my intake manifold off on my 1977 Mercruiser MIE 330 s/n 5551947 and can see the intake valves through the air intake ports.
They are all pretty black and crusty looking (except for the one getting washed by a coolant leak - I'll fix that).
While I'm in there should I spray something...
I've been loosing coolant every time out, about 200 ml or so, with no sign of leaks on the engine. I noticed a smell of coolant on start up for a few seconds and some white smoke. No sign of milky oil on the dipstick.
I removed the distributor and see coolant on top of the block near the...
Replacing my slave solenoid and the new one looks similar to the old except the two small terminals have a letter I and S beside them.
What could this mean? Does it matter which one gets the ground ?
Dewinterizing the boat and have a no start scenario with my 1977 MIE 330.
First try starter engages then quits.
Second try, nothing at all
Check all connections, poke the circuit breaker button, not popped
Third try slave solenoid clicks, but no starter action
Could this be due to a faulty...
I thought GM stopped making the 7.4 in 1999.
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Thanks
John
My Mk3 7.4L is spec'd max 3800-4200 WOT
It powers a heavy (10000 lb) single shaft v-drive planing hull
Current 19X18 3b prop gives 22.5 knots WOT at 3850.
It was suggested to me that I may be lugging the engine running it at a 3200 cruise(16 knots) with this prop .
I'm considering a reprop to...
Planning for an eventual repower and wanting to go SBC to replace BBC (stay calm):
If a BBC 330 HP cruises at 3200 rpm peak TQ 420 with a 1.99 ratio that's 835.6 Prop TQ
If a SBC 330 HP cruises at 3200 rpm peak TQ 370 with a 2.47 ratio that's 913.9 Prop TQ
Why not go with a small block?
My boat is a 26 Tollycraft flybridge cruiser
10000 lbs, single 454 V-drive 1.99:1 reduction
This is a 1977 Mercruiser WOT spec range 3800-4200 rpm
I've got room for a max 19" diameter prop
Original 19X20 3-blade gave WOT 3700 (too low)
I repitched:
Now 19X18 3-blade gives WOT 3850 (better)
It's...
Looking at a repower and my Canadian Mercruiser dealer said that at some point in the future we will no longer be able to buy non-catalytic converter gas engines.
I've heard that the ECT version gas inboards are more expensive and trouble-prone. Anyone know when? What's the case in the US?
Having recurring problems with my electronic ignition system at fast cruise, and have done everything I can think of, so starting back at square one to make sure I have the correct Petronix Ignitor for my 1977 Mercruiser MIE 330 (S/N 5551947L).
Petronix tech support says they need the...
My local Mercruiser mechanic suggested I replace my Blue Streak coil as it was not suited for my engine.
Problem is that we have tried two different coils (PerTronix 40,000v and another brand I can't remember) and they both produce the same result, only starts at high rpm and stalls below 1700...