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Brand new 3.0 gm/mercruiser but wont start

Guuben

New member
Hi

Some details: I have a brand new "mercruiser/gm 3.0" engine with all the bought components brand new too.

So far so good but the engine wont start - i have tried many days now and i get no progress at all.

I have regulary spark at all 4 sparkplugs and the fuel pump gives good pressure too.
Its a EST Delco ignition system.

The engine is in my boathouse before installing it to my boat and there is just for now simple wirings, e.g. wire from battery direct to coil (the purple wire). And the two with wires from distributor is cutted and the black wire from distributor is not connected anywhere. Nothing to or from alternator or any wiring harnesk. I tried to ground the blackwire and tried it to positive 12 v - at 12 volt connectiion the sparks go off as it shall what I understand is right too (for shift switching)

I tried to use the basic ignition setup with the with wires too but no help of that.
I have also tried to rotate to widely the distributor when cranking the engine - no help.
Sadly I have no ignition timing light and it takes at least one week to get one here where i live. It is now ordered because I must have it anyway
All what i get - sometimes - is "the big bang" from exhaustriser...terrible and scary :)

No tachometer is installed or anything else - no wiring at all, ecxept the "must have" to start the engine. Only the 12 volt to coil and the wires from coil to distributor (there is some filter on that -noisefilter for radio?)

The battery is good and cranks the engine very rapidly. I get 13 volt at the distributor from the coil - the pluswire.
The firing order 1,3,4,2. starting from the Barr-marine factorymarked number one. I have checked Youtubes and compared that number one is the correct one.

I tried to make some ohm-metering at the coil.....all was good except that i had 1,2 ohm where the est delco manual says 0,4. But i am not good at these electrical things and maybe my cheap "all-purpose" handyman-meter cant take such low ohms (I think so). My lowest metering for ohm starts from X 200.
The pins at those keyed connectors are all okey - I found out by Google that those pins can sometimes go out of order. I checked and i must say - really bad construction so i put today some rapid glue to secure them better in the base.

Please try to help a man in big trouble :)
Guuben from Finland.
And excuse me for a long letter.
 
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doesn't matter if it takes 5 years to get a timing light there, you can't make do without one. Running the engine under load with incorrect timing can destroy the engine.
 
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doesn't matter if it takes 5 years to get a timing light there, you can't make do without one. Running the engine under load with incorrect timing can destroy the engine.

agree but he should be able to get the timing in a range where it should start.....can't be THAT far off.
 
Philipp and Bondo.
You where just on the right track:

I dramatically turned unclockwise the distributor as far as 90 degrees on the distributor yesterday and ...wrooom...it started and running okey....ohhh what a release
Before i just turned more and more ending at 20/30 degrees to left and right on distributor when it didnt start at the "ready made Barr company basic settings" (the distributor comes installed with the basic 3.0 GM engine from Barr)

Something is very odd: How is this possible ? The GM-block and Barr engine is manufactured in Mexico...i just wonder, saying no more :)

Now i changed the sparkwires for 1,3,4,2 one step uncklockwise and thats working.
Now my sparkwires for cyl 1 and 2 goes close to alongside the engine and 3 and 4 goes more out from engine.
I have not seen any pics etc with such installation....but this doesnt matter ...or does it?

In other words...the factory blue marked spot on the distributor for cylinder 1 was wrong.

My friend found his old timing light so I get that tomorrow so I can make the basic EFT ignition timing correctly (1 degree BTC)

Nota bene: Sparkwire for cylinder 3 is hardly long enough in this outfit.....the No 3 sparkplug and distributor No 3 is more far away now. (the sparkplugwires comes in one set)

Thanks for support
Guuben

Now i can prepare the engine for the boat and take off the old one...this is a full inboard engine - not for sterndrive.
 
Ohhh, one moore thing:
Is it a (real) possibility that unburned fuel from all my attemps to start the engine has gone down to crankhouse and mixed now with the oil. I mean, I think it took "a lot of gasoline" from my fuel canister. Maybe best to check that? The pistonrings are still rather "rough". My guess is 15 ounces about (1/2 liter) maybe some moore. But only one time i poured one tablespoon straight into carb. I used a lot the acceleratorpump when it didnt start at the beginning.
I had once the mercruiser 6 cyl inline so i am little common to "mercruisers".
 
Shall there be a "free flow out" of air from the ventilation hose? I thought it shall be more like breathing?
Something is wrong? The engine runs surprisingly nice on idle but the gasoline consumtion is terrible: a couple of minutes on idle and some revs and whoops...there goes about 15 ounces and moore. Its like the carburetor "cork" (I dont now the english word) is not shutting the flow from the fuel pump. I had the carb off and when turning carb upside down the cork and needle shut off the flow when blowing with mouth to inlet.
The sparkplugs are all deep grimy - i cant really understand how the engine can start and run at all :)
Sorry for my poor english.
 
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