98 405 Port Engine Will Not Start

[bud37]

Bit late I guess....but one question....do you have someone that can hook up the diagnostics to the obd port....??

[Johnnykey]

Hi, If it were My no start condition, I would have someone crank the engine over while spraying Carburetor Cleaner, directly into the spark arrestor on the intake. A 1/2 second spray is all you should need while the engine cranks, to determine if your spark system is working. The motor will jump around a bit and fire on a few cylinders, a simple yet effective test. Of course there are all kinds of safety caveats attached to this procedure. But seeing that you already have open buckets of fuel filters and gasoline around, I feel somewhat confident that you won't blow the boat up with my advise. I am completely Against using "either" or "starting fluid". That stuff is dangerous!

[Serendipity]

Gentlemen, Gentlemen,

After being a Service and Parts Manager for 25 years. This is your laugh for a few days, maybe a month Michael gets the dumbest award for December.
First thing I always preached to my mechanics, follow the trouble tree. I don't care if you replaced part #1 last week, follow the trouble tree and start from the beginning. Look at the schematics and what do they say to you?

So Michael, took for granted I had a fuel issue, which was my first mistake. Having just filled up with fuel I took for granted it was somehow fuel related. I was convinced of it, so I replaced the fuel strainers on this 7.4 MPI Fuel Injection 454 engine. Still would spin over, so I swapped sensors from each engine, nothing. Disconnected the batteries and swapped ecm's, nothing. Went out an purchased a $100 really nice fuel injection kit. Got pressure specs from your fine gentlemen and they were 42-44 and right on the money. I replaced the ignition switch..
Then summer hit and my
3 businesses consumed my time. I have tried everything except checking the spark, which should have been where I started.
We slow down a little bit in November and December, so I was determined to get this port engine started.
There is no way it could be spark? New wires, New plugs 100 hours ago and no way in hell it could be a distributor cap or rotor button. Right!

Wrong, I took the button up and it had a little corrosion on the shaft, button looked fine at first glance and would this really cause the engine to die? Yes indeed

So the button had a hairline crack on it as shown. So I drove to an auto parts store, one that seemed to have more GM parts when I searched online.
So I walked in a gave them the button. Make and model of your car sir, 1998 Carver 405. Say what

Yes I will be ordering 2 new Mercruiser caps and rotor buttons, I just wanted to know if the damn thing was bad with a hairline crack. Guys were really helpful and had just buttons in stock. Sir, would you like the aftermarket or the GM version, it is a $6 difference. $3 compared to $9 and I took the GM version naturally.
Getting back to the boat, I cleaned the distributor shaft and installed the new button.
Put the cap back on and convinced myself it could not be this simple.
Turn the ignition and the port engine started purring like a kitten immediately. I mean started immediately as soon as I hit the key.

So guys, I am here with egg all over my face, in the hope this helps someone down the road. Ya were the bomb with everything you offered or suggested I do. Why do men have to be so damn hard headed and stubborn?

Thank you for your knowledge.

Michael

[bud37]

Thanks for posting.......it is good to see that attention to the small, seemingly simple details and working thru it has paid off in the long run.......good luck and stay safe..

[Viper]

Michael Michael Michael, I suggested twice to check the ignition system/spark You're right though, it's easy to get stuck on one path even when everything is indicating that system is fine. This is also a good example of not assuming all new parts you've just installed are fine so it must be something else. Good on ya for putting this out there though, I have no doubt it'll help others.

[Serendipity]

Yes Viper, you did suggest I check the spark


I just took for granted it could not be anything dealing with the dist cap or button with so little time. I reminded myself I have had brand new vehicles pulled off transport carriers with bad alternators on more than one occasion.
New from the factory with 5 miles on them. It happens!

Rule number #1 follow the damn trouble tree and even an old experienced dog like myself gets off on a mindset sometimes.

Hopefully, my posting this here will repeatedly serve to someone else to check the basics first before going down the more difficult route I did.

This is why I send ya beer money from time to time.
Ya are worth every penny I have ever spent.



Michael