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Help no spark 1980s oil injection 70hp

Have a no spark issue in a merc 70. Before I get the manual this week I wondered if anyone knew what connections I should be looking at first before the stator cdi or switchbox testing. Ran a year ago. I’ve now taken it on as a project. Any help would be great. 😁
 
I tied disconnecting the kill switch but put it back on as meter shows nothing wring with it. As for the tilt has it got something in that line that stops it? Does the engine need to be in a certain position. Tilt switch as in so,etching t9 do with the power trim? Thanks for a response ��
 
I have a reading from which I think is the stator of 14.3 on the 200 ohm setting. Havntaclue any ideas on that? Manual still hasn’t arrived. I’m desperate to get out on it once at least before the fall here
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I for the life of me can't find my stator spec. chart.But a no spark situation is usually the kill system shorting,bad trigger,or switch-box/power pack.This is a long shot,have you checked the ignition switch and that the kill cord on the control is functioning properly.
I'll have another look for the chart in the morning.Here's a link to the CDI troubleshooting guide. Page 89 for the Merc. http://www.cdielectronics.com/troubleshootingguide/

 
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I checked the switch in the control box and is working perfectly. All wires and connections look very good in there too. At the engine side they all look very clean. On inspecting the engine there was a wire disconnected. I’ve connected it back up but still nothing. I can’t see a tool to upload a photo. I am more than grateful of your time I really am. After buying 2 engines for my rib on the strength of being “just needing a service” they have far more wrong with them so scrapped those projects. This boat have now with the merc 70 I have a better feeling about. The people I bought it from seem genuinely surprised it doesn’t run. Other thing wrong is the tilt switch solenoid is intermittent so I’m replacing that. Kind of hoping to take it apart so I have a spare. It clicks and sometimes works. Thanks again. I will look at the link now. ��
 
Hi Update! I have a spark! There were a couple of connections on the lower part of the engine. I turned them all and got a spark! I’m going to clean the connections now. I’ve since stripped the carbs as two were flooding. It did fire on two cylinders, striped them and cleaned the jets. I e noticed one metering jet is far bigger than the others. Not sure if that makes sense or should try another thread. Thank you havntaclue for the help. It kept me going
 
Hvntaclue Im baffled. Now no spark. Strange. Checked ohms on the stater and it is 3.45 and 3.5. The lowest in the scale is 3.6 to a higher reading of something or other. When I got a spark it was bright and strong. Kinda hoped to have it on the water by now. I’ve cleaned the carbs because of when it fired it wasn’t getting much fuel I think. Now they are good although one have a much bigger metering jet in! ��
 
On further analysis I have spark on the lowest cylinder which guess number 3. Changed wires to each coil to find they spark on each when I put number 3 wire on two then one. Wired back to normal then fiddles with the wires that are on the trigger. The main back shroud is on and undamaged but tools like it’s had a bit of use twisting back and forth. Then I got spark briefly on one and 3 still all good. Then back to spark on three only.
Im guessing trigger wires are broken internally. I’m guessing I have to take everything out as in flywheel stater then trigger so to get access to the wires. Is the flywheeel going to be super nasty to take off??? ��
 
Sounds like you trigger is done.You could try a continuity test on the trigger wires,pare a little past the bend/twist,if there's a break,solder in and heat shrink a replacement wire.Not a lot of cost involved if you can DIY it,or if needs be take it to an electrician.Then OHM test it,still haven't located my charts,cheaper than buying a trigger if it works
To remove the flywheel,you will need this tool, https://www.amazon.co.uk/Mercury-Mariner-Yamaha-Flywheel-Removal/dp/B017KZI1Z8.Plenty on ebay.Do not remove the flywheel by removing the eight blots as I don't think you can remove the trigger this way.
 
Thanks fishinlite I have now bought one. I’m in the uk so to was 40 pounds I paid. Will be with me on Tuesday. ��

havntaclue I will try that with the continuity test. Ive done a lot of wiring, soldering so that’s not a problem. The sleeve or heat shrink looks undamaged but looks tired at the bend your talking about. Hopefully I will get it off on Tuesday although I have anything to lock the flywheel with. Can’t wait to get it running. Pouring with rain here so can’t do any other bits. ��
 
I’ve just stuck a meter on continuity. It gives me a reading in ohms but on the brown wire if I turn the trigger back and forth a i get a reading but keeps dropping out to a no continuity or resistance. Does this mean the brown wire is the problem??
 
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