Starting procedure - Mercruiser 4.3

[tinstaafl]

Our boat has a 4.3 mercruiser engine fitted. It is the carb version, not the EFi version. It's only 2-3 years old and barely used by the looks of things.

Obviously this is a very popular engine so somebody must be able to tell me the easiest and quickest way to start the thing from cold...

The manual says 3 pumps and then set it at the indent just forward of idle. I saw a Mercruiser video that demonstrated a single pump and then set at the indent.

The quickest way I've found is to use the flooded engine procedure - where you open the throttle to maximum, turn over the engine and pull the lever back when the engine starts to fire. Unfortunately the only way this works is to actually flood the engine first /forums/images/graemlins/smile.gif

I'm sure I'm being stupid and missing something and it doesn't really matter, I suppose, since the thing starts in the end, but there must be an easier way...

tinstaafl

 

[[2068]]

What worked well on the 5.0 carb was three pumps, then start with a fair wodge of throttle, where a "fair wodge" is more than the indent, but less than wide open, probably about half throttle. It might vary on the smaller 4.3...

dv.

 

[itsonlymoney]

Agree with above. 3 pumps and half throttle.
Ian

 

[wakeup]

Ditto with my 5.0 carb V8, followed by lots of free reving below 2000rpm then settle to idle

 

[Alistairr]

I hope you get some good answers here, so as i don't
spend all weekend doing this again!!!!

 

[capnjack]

Assuming new plugs, mixture and timing are set correctly, then 1-2 pumps with the throttle set to indent works for me.

Last year the dumb mechanic who was supposedly a "Top Guy"!!! set the mixture too rich and clogged the plugs. Wouldn't start well at all. Found another mechanic, with a brain this time who sorted it out, no problem any more.

Try a few different proceedures to see what works best for your engine. Pumping the throttle primes the engine with fuel, it's then a good idea to let it idle for a minute or two to warm up. The manual says its' not a good idea to let it run out of gear for long periods as this can damage the gears by lack of oil circulation.

Good luck
Capn Jack

 

[Roy]

My last boat had two of these things and I pumped em twice at least, gave an inch of throttle and fired up. Went ok every time. Make sure you warm her up - just enough to lift the temp guage needle off the stop and then into gear and away. They tend to stall when under load if still cold.

 

[tinstaafl]

Thx chaps, will try some of these techniques /forums/images/graemlins/smile.gif

tinstaafl

 

[moondarra]

1: pump throttle twice them place in halfway position

2: turn ignition key

3: wonder why nothing happened. Press awkward button thingy so engine is not in gear

4: turn ignition key again

5: wonder why nothing happened. Try wiggling that funny coily cord thing. Ask the wife if she's moved any switches.

6: shove throttle all the way forward. turn key.

7: wonder why nothing happened. Repeat steps to 6 a few times until the battery goes flat. Tap battery switch with blunt end of screwdriver.

8: check fuel filter. (if you can find it.)

9: wash fuel filter under tap. reassemble. wonder if you should not have washed it under tap.

10: turn key. wonder why nothing happened. try whatever the bloke in the next berth suggested even though he's got MPI

11: wonder why nothing happened. consider staying in the marina this weekend. after all it looks a bit choppy out there.

 

[aquaholic]

I have a 3.7 merc, tried all of the above, eaisiest way for it start now is no pumping, push throttle to indent, then turn the key. Works each time..