Overheating. Almost done saga.

Juliery said:
Mine r

Mine also runs at 170 all day long, also salt water, closed system. That's a great temp for efficient combustion. Performance boats will run even hotter. Markrsimon is correct: overheat is at the plus side of 200.
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Your right on, 170 is good if your pegged! 180 and fluctuation is when you worry
 
I'm new to the boating world, but a master mechanic. I've actually been running my fresh rebuild without a Tstat, pegged for a while she'll only climb to 130 so gonna throw the Tstat in, maybe a 140, raw water cooled
 
Well if anyone still following this thread, I got the call today. Slip opened up. Tomorrow morning we taking the boat to the pros at the fancy marina next door.
Birthday is Tuesday, holiday weekend soon, maybe i get lucky.
Most likely with my luck they gonna tell me needs new engine.
PS for those not in mid Atlantic, is been brutal heat. Dont feel i missed any boat weather. Was at marina today, took zodiac down river, sweat soaked, needed shower and clothes change. I just wanna get this running for the leaves change and fall. Best time of year around here.
 
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Since I am a glass half empty guy & have the worst luck. This engine only has 560 hours. But in the event they tell me i need a new engine what are my options? I saw a thread on here about problems with Jaspers. Planning ahead. Also, i have heard that 7.4 are hard come by. As alternative can i mate a 350 mpi to my Bravo 1?
Or just a 5.7 carb? I know going smaller is never good, but I really dont wanna wait many months to find a 7.4.
Wiil say guys, i learned a valuable lesson at 68yo. These are toys, and no matter how much we like to do our own maintenance, in season, let the pros do it. Had i taken this to them back on June 5 it would been fixed months ago and i wouldn’t have wasted a summer messing with this.
 
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Michigan Motorz has a remanufactured 7.4L long block for $4299.00 ( https://www.michiganmotorz.com/7-4l-454-ci-marine-engine-1991-95 ). You would still need to pay to have everything transferred over.

A brand new 7.4L long block is $6899.00 ( https://www.michiganmotorz.com/7-4l-454ci-vortec-marine-engine ).

A brand new complete 7.4L engine is $13,875.00 ( https://www.michiganmotorz.com/7-4l-454-ci-complete-engine-package-1986-later-applications ).

It really depends on how much the mechanic will charge you to transfer everything over from your old engine and how much you want to pay.
 
Pirate Lady said:
Chip,
Whats the difference between #2 and #3?
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#2 is the block and heads plus the valvetrain, you transfer over all your accessories

#3 is turn-key ready to go (as much as that can be said for anything related to boating)

Chip has a great point, if you were moving everything over to a new longblock yourself, it would save you $$$

My boat has 2 new long blocks but all the old accessories and those love to crap out one at a time, over time :eek:
 
Jegs has the reman'd longs for a little less.
ATK Engines DMK1: Remanufactured Crate Engine for Marine Applications with 1996-2003 Big Block Chevy 454ci/7.4L | JEGS

If it comes down to it, look at local machine shops and see what it would cost for a rebuild on yours or a wrecking yard block. We have found some great deals on good used motors with low miles. That would make a great marine build. That is my winter project plan is to get two used blocks and build them up for marine use. Have them sitting just in case.
 
Pirate Lady said:
Well if anyone still following this thread, I got the call today. Slip opened up. Tomorrow morning we taking the boat to the pros at the fancy marina next door.
Birthday is Tuesday, holiday weekend soon, maybe i get lucky.
Most likely with my luck they gonna tell me needs new engine.
PS for those not in mid Atlantic, is been brutal heat. Dont feel i missed any boat weather. Was at marina today, took zodiac down river, sweat soaked, needed shower and clothes change. I just wanna get this running for the leaves change and fall. Best time of year around here.
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Still following. I am interested to know overheat cause. If its the engine, which I hope not, Ill throw in my advice/experience - I was in this situation in 2010 -two tired old 350 mags in the pachanga. I wrung my hands, did great gobs of research, eventually settled on replacing with carb'd 357 4V Alphas from Mercury and installed by the dealer -was spendy yes, but lots of piece of mind because -
- Dealer installed got me 2 year warranty on bobtails (for those dont know bobtail is engine AND outdrive not just engine) and, because mercury marine running a special, I got additional 1 year warranty.
-Didnt have to use all those old components like Phil S mentioned,
-Direct fit with the transom holes/assemblies, wiring harnesses etc

To replace a 7.4L, I have been told numerous times by Mechanics (ones I trust) that 7.4L parts are harder to come by and more than one has told me when time to upgrade, do so with a stroker - Meaning Mercury's 383 Scorpion (or lesser priced 383 mag). Why?
Lighter weight,
Direct fit with Bravo and Mercury makes mount adapters off the shelf.
Same/more horsepower (7.4L =330 383 Scorpion stock I think is 400?). you'd give up a bit of Torque but in your boat not a big deal.
-By the time you get done rebuilding the 7.4L labor engine in/out, you'll be at the price of the 383 install (13Kish) but save about 3 weeks or more in time. These guys I think have them for around that price. So would Detroit Motorz and easy to also get by the dealer who will want to order through them in order to get warranty.
383-MAG-Bravo-4V-350HP__79647.1490399277.jpg
 
Pirate Lady said:
This week be 2 months. We fixed or replaced…
Intake manifold gaskets
Carburetor
Thermostat
Thermostat housing
2 temp sensors
5 coolant hoses
Bilge pump hose (found a hole in it)
Impeller
The big pump on front of engine.
Flushed engine multiple times, cleaned that out like new.
Pulled outdrive ….
Replaced the hose going from lower vent holes thru transom to impeller (bravoitis)
Bellows cables everything in there inspected or replaced.
Fixed loose wire going to trim switch starting to cause electrolisis.
Bravo 1. In excellent condition after 30 years. Engine too, 560 hours.
Previous owner used once a week to fish on Saturday morning then kept in a boatel.
I swear we did other shit too.
Thank god for friends. Total cost $1200.
mechanic buddy/friend test ran today, all seems good. Tomorrow we going down river out to the Bay and run the piss out of it to see if we got it all.
Wish me luck.
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You changed boats when did you move up from your 220 DA
 
FOUND THE PROBLEM! 1 day at pro mechanics. Metal water pickup tube between outdrive and water pump almost totally clogged. 3 months I wasted with a shade tree mechanic and these guys found it in 4 hours. Lesson learned. Cant promise have done by weekend, depends on parts availability but will try. Today’s my birthday and this made my day!
 
Phil S said:
Hold on now ...

Let's go glass-half-full and maybe they come back with something simple or cheap.
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Simple yes, cheap we’ll see, pulling both outdrive and the top part that outdrive bolts to, and fixing both trim sensors, gauge side dont work and he said the limit switch is looking bad. Replacing both. Plus haul & block.
 
Pirate Lady said:
FOUND THE PROBLEM! 1 day at pro mechanics. Metal water pickup tube between outdrive and water pump almost totally clogged. 3 months I wasted with a shade tree mechanic and these guys found it in 4 hours. Lesson learned. Cant promise have done by weekend, depends on parts availability but will try. Today’s my birthday and this made my day!
Click to expand...

Nice! See now you have a solution, plus a whole bunch of other items you don't have to worry about.

Seeing all these issues lately about low water pressure and Bravoitis, I'm doing through hulls and strainers, impellers, new hoses etc this off-season.
 
Doing the same thing Phil without the Bravo issue. SeaCocks to Impellers. I’ve already started ordering hoses and two new heat exchangers and hoses. Fun Fun
 
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