Author Topic: Diagnosing the 3.7L Ignition Issue. (Read 33896 times)

dorelse · « **Reply #100 on:** August 27, 2016, 12:41:55 PM »

Quote from: Rich_V174SS on August 27, 2016, 08:46:39 AM

That motor sounds good. The dog doesn't know what to make of that growling beast.

Quote
I am still not confident the engine will fit. At a minimum, I think the Alt will have to be relocated down like Rich's. So I've got some measuring to do...

If you switch to an alternator kit like mine it will increase the length of the engine up front, perhaps making it harder to fit in the boat. If you go with one of the alternator setups like those in the ebay links I posted earlier then the engine stays more compact. Maybe the seller can sell you just the brackets instead of a whole package, wouldn't hurt to try contacting him.

Yep, going to send them both a message...would be much easier fit too.

dorelse · « **Reply #101 on:** August 27, 2016, 08:11:02 PM »

One more video today...let the motor run for 20 mins straight. Not one issue, shut if off, restarted immediately, no problem.

I dunno really what's left to do besides get it ready to drop in. (Well, collect parts now for the extra 20HP upgrade, 170 -> 190 HP.)

Ok, one thing I think isn't right is that the Purple/yellow wire must be on the wrong terminal, its always putting 12V to the coil. I think that should be on the same terminal as the yellow/red one so that it only has power when starting right? The purple resistor wire is putting out 7.5v, I was expecting to need to shorten it to raise the voltage to a higher number as needed.

http://youtu.be/qa7zwqvQP5U

Rich_V174SS · « **Reply #102 on:** August 27, 2016, 11:53:06 PM »

Quote

Ok, one thing I think isn't right is that the Purple/yellow wire must be on the wrong terminal, its always putting 12V to the coil. I think that should be on the same terminal as the yellow/red one so that it only has power when starting right? The purple resistor wire is putting out 7.5v, I was expecting to need to shorten it to raise the voltage to a higher number as needed.

No, the purple wire is correct where it is. The purple/yellow wire should show the same voltage as what's at the coil when the engine is running, more when cranking the engine to start. If you switched the purple/yellow to the other terminal then the yellow wire would also see voltage while the engine is running because power is coming from the coil's resistance wire and the starter will continually engage.

dorelse · « **Reply #103 on:** August 28, 2016, 11:14:19 AM »

Hmm...ok, I thought 12V at the coil was too much and it was supposed to drop and use the resistor wire when running.

Rich_V174SS · « **Reply #104 on:** August 28, 2016, 07:45:09 PM »

Quote from: dorelse on August 28, 2016, 11:14:19 AM

Hmm...ok, I thought 12V at the coil was too much and it was supposed to drop and use the resistor wire when running.

That's what is supposed to happen. When it's running check the voltage at the (+) of the coil and if it's 12+ disconnect the purple/yellow wire from the solenoid and check the voltage again at the coil. If it drops then there's something in the solenoid that's keeping power connected. Perhaps a faulty solenoid or the wrong solenoid. This is why I don't trust aftermarket parts for some things.

dorelse · « **Reply #105 on:** August 28, 2016, 11:48:50 PM »

FYI Rich - Your motor's in Canada getting fixed:

http://rosseauroad.ca/service/marine-service/

Rich_V174SS · « **Reply #106 on:** August 29, 2016, 07:43:16 AM »

Quote from: dorelse on August 28, 2016, 11:48:50 PM

FYI Rich - Your motor's in Canada getting fixed:

http://rosseauroad.ca/service/marine-service/

What the hell?!?!?!? I should be paid royalties for the use of my pictures. I also saw that pic being used on an ebay sale for an alternator conversion kit. I actually won the bidding on that kit so now I have an extra.

Rich_V174SS · « **Reply #107 on:** August 29, 2016, 08:37:43 AM »

What do you think? I'm sending this email to that marine service place:

Hello,
This email is concerning a picture that is posted on your web site in the marine service section. Someone had brought it to my attention that you're using a picture of a clean Mercruiser 3.7 liter engine sporting a sawed-off flame arrestor in a light green boat. Well, I am the owner of that engine/boat and found it curious that you would choose to use it in your advertising. I'm located in Connecticut USA and know for a fact that no work on this boat or engine had been performed at your shop as I do all my own work. I'm flattered that you would use one of my pics and understand that what is posted on the internet is pretty much public domain but to use my pics in advertisement without permission seems a little unethical. I'm not usually one to seek legal recourse but would request it be removed. To show proof I am the owner I've attached links to a couple of my youtube videos showing the same boat below.

Thank you.

Sincerely,
Richard

75starflight · « **Reply #108 on:** August 29, 2016, 09:09:02 AM »

Sounds good to me, Send it!

Rich_V174SS · « **Reply #109 on:** August 29, 2016, 09:17:56 AM »

Ugh! Mail delivery failure! I sent to the email address listed on the company's billboard, billjen@rosseauroad.on.ca and it came back with that message.

Plugcheck · « **Reply #110 on:** August 29, 2016, 09:19:35 AM »

Sounds like an appropriate response. Somewhat curious how much work they actually do if they need to grab pics from the internet. Back to the original thread, is the ignition system stock? Guess I was thinking you upgraded to electronic ignition and a low impedance coil which would then require 12 VDC when running. Fairly typical on many engines to create a bypass for full voltage at coil while cranking to improve spark output. Sounds like your close, are you waiting to upgrade the carb/manifold before installation or after? Be kinda cool to see/feel the difference with real world testing, but I understand the access to the engine might make that tougher.

dorelse · « **Reply #111 on:** August 29, 2016, 09:57:34 AM »

The ignition system is stock actually...so that means points I think. It has a new stock coil. The

I'm going to keep the engine on the stand for the winter. I'll winterize it which, (Rich?) is just draining the heat exchanger I think. Or I suppose RV Antifreeze goes in there.

Over the winter, I'll collect the parts for the 190 upgrade. If I'm honest, its running good enough that I don't want to mess with it...but it might be very difficult to add all those parts once the motor is stuffed in the boat.

I need several things...inner transom bracket that will accept P/S. 4-Barrel intake, QuadraJet Carb, there's an oil cooler that comes with the 4 barrel intake as well I think.

And...a 3.7L matching outdrive (or change out my upper) ...you know...the little bits...

So...my winter will be collecting parts and then I'm hoping to have a engine swap party sometime in the spring. That way, I can run the motor again with all the new bits on before its dropped in.

Rosscoe · « **Reply #112 on:** August 29, 2016, 05:12:31 PM »

Quote from: Rich_V174SS on August 29, 2016, 07:43:16 AM

Quote from: dorelse on August 28, 2016, 11:48:50 PM
FYI Rich - Your motor's in Canada getting fixed:

http://rosseauroad.ca/service/marine-service/

What the hell?!?!?!? I should be paid royalties for the use of my pictures. I also saw that pic being used on an ebay sale for an alternator conversion kit. I actually won the bidding on that kit so now I have an extra.

Lol
It does get around.

Motor sounds pretty smooth D. Thru hull on Bar fly?

dorelse · « **Reply #113 on:** August 29, 2016, 05:58:54 PM »

Quote from: Rosscoe on August 29, 2016, 05:12:31 PM

Motor sounds pretty smooth D. Thru hull on Bar fly?

Thinking about it...I think it sounds awesome (for a 4 cylinder)...and would like to keep that sound. The whole reason for doing this is to try something different...different setup.

A through hull might be cool. Supposedly, though, the 3.7L has a reputation for ingesting water...

Plugcheck · « **Reply #114 on:** August 29, 2016, 07:34:23 PM »

I assume a single outlet? Can you find an exhaust that splits two cylinders into one port each? Maybe a split with one longer runner to alter the exhaust tone? Non-Harleys been doing that a long time to create the sound. I know-crazy talk!😉

dorelse · « **Reply #115 on:** September 03, 2016, 11:29:17 PM »

Well, winterized Barfly today.

Plus side...took out the bench seat for easier access to the oil pan to change the oil. I have got to put a Fumoto Valve on!

Going to be measuring up the compartment tomorrow to make sure the 3.7 will fit.

Just a reminder to clean out those drain holes...one was completely plugged up after partially draining. Cleared it out and all this came out.

Also sealed up the gas tank with a new sender & gasket. No more smell!

Then the dog got sick...someday she'll learn Frogs aren't for eating:

dorelse · « **Reply #116 on:** September 03, 2016, 11:36:47 PM »

Still runs great!

http://youtu.be/TLqkXccr7e4

Rich_V174SS · « **Reply #117 on:** September 03, 2016, 11:43:48 PM »

You see where the two bolts are that are holding down the front engine mount on the 3.0 liter? Mark those spots about 6 inches forward and that's approximately where the 3.7 liter engine mount will have to go.

dorelse · « **Reply #118 on:** September 04, 2016, 12:06:38 AM »

Will do. I'm definitely going to have to get into the floor and see how the stringer(s) are laid out. I'll need to build a new engine mount obviously.

thedeuceman · « **Reply #119 on:** September 04, 2016, 07:31:02 AM »

I have the following 470 parts, they're yours if you want them
Coupler, appears to be in good condition
Exhaust elbow
Transom plate, not sure if it will except power steering or not
Upper Drive, appears to be locked up may or may not be rebuildable

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