Offshoreonly.com - What motor do I have here?

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Quote:

Originally Posted by madbouyz (Post 4629973)

Once upon a time I launched with a completely new re-power that was a total unknown in terms of what to expect speed wise . On the way to pick up the mechanic I was really impressed with the performance numbers I was getting.
The mechanic got on board and after eyeballing everything took the helm and got it up on plane . A minute later he slows back down and pulls out a small screwdriver and fiddles with the rear of the tach .
My perception of great performance numbers went completely out the window . The damn tach was set for the wrong engine !

so you got me thinking here... can you guys tell if this tach is set right? I’m guessing I need to switch it to 4 pulses??

My quicksilver gauge with that back on a 2001 454 mpi is set on 4p. And it reads correct I checked it a tach/ timing light

on the back of the tach its called the pole setting. Has to be set to the correct pole / vs engine & cylinders --- also correct setting per outboard engine or inboard engine as many tachs are combo

Well, the engine has Vortec heads (4 intake bolts per side + straight/up down) + edelbrock carb and intake.

Yes. change tach to 8 cyl/4 pole.

Alright boys it looks like I got lucky, I think I have a 5.7 not a 5.0.
Take a look and tell me what you think

Maybe it’s a 355c.i. and the seller/broker confused displacement for horsepower? Looks like a 5.7 casting mark, but that casting number on the block will give more info. Didn’t see a Mercruiser tag above the starter at the rear of the block on the video.

You guys are great for trying to help. This is the stuff that first built OSO. Thank you.

the carb is a weber Mercruiser old school that was not used by them since 1998,after that Merc went to the 2 BBL Rochester and then the 2 BBL TKS carb from 2003 up.

It is a 5.7 but IMO a reman from whomever. Your oil pan has had it and will leak motor oil soon with vast amount of corrosion eating thru the pan. .

The starter needs to go and you need alot new cables and wiring. The engine will never run right with the corrosion for all the electrical side that I seen in your short video. This also effects ignition output even for carb apps. The corrosion it causes alot of electrical resistance. .

The exhaust is GLM and if they are aluminum ran in saltwater - they need to be looked at ASAP before you hydro lock the engine. And the same goes for cast iron offerings. The riser gasket fails easily in saltwater as well. If its a sold motor my guess 250 to 260 hp at the prop. . .

in one spot it looks as thou possible external water leak at the block area.

Also your fuel line is NOT USCG approved -

also the spark plug wires are all tie wrap together that cause EMI and RFI. between them.

Merc Carb apps 5.7 was WOT 4400 thru 4800 rpms when solid and oem stock.

Man I would check out the intake being aluminum - in salt they do not last

Hey Romeo, it's 'some guy here'

Let us know what the new rpm is after maing the tach right...and then we'll go from there.

In the meantime, check to see what spark plugs are in it.it is an extremely typical mistake to put plugs in it from earlier years SBC's. Earlier than Vortec heads used something like ACDelco MR43T. The Vortec head uses a longer reach spark plug than this.. This is part of reason why Vortec head is so good.it was casted to use a longer plug to get electrode closer to center of combustion chamber when piston is at TDC.

Your 5.7L Vortec Engine should have AC Delco MR43LTS spark plugs or equivalent. Gap should be .035"-,040"

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Quote:

Originally Posted by SB (Post 4630109)

lol thanks SB, I was waiting for “some guy” to respond to the video. Thanks for the tip, I’ll fix the tach and check/change the plugs before I take her out again and then report back with the proper rpm.

And BUP, thanks for the advice, I just ordered new manifold riser gaskets and I’ll be sure to check the manifolds while I have it apart.
I’ll also be redoing/separating the plug wires after dinner this evening and already ordered USCG approved fuel line to replace what’s there. I’ll work on the rest of the wiring in the coming week.