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87 MCM 180 wonbt run

4

4winnsdan

New member
"Hey guys,
Please provide som

"Hey guys,
Please provide some of that incredible insight and wisdom you all have to help me solve my problem. I had a Pertronix Ignitor installed last fall and didn't change out the coil. This past weekend the engine cranked but wouldn't start. I found that I wasn't getting any spark so I started trouble shooting the ignition and found no spark at the coil. In the process of checking for spark I ruined one of the plug wires so I replaced all of those.

Today I received and installed the Pertronix Flame thrower used with the Ignitor(3 Ohm coil). When I installed the coil I left off the resistor wire from the choke and the purple w/ yellow stripe coming from the solenoid and jumpered from the solenoid(P/Y stud) to the coil + and the engine fired right up and ran flawlessly for 5-10 mins until I shut it down. Having declared victory I cut the purple resistor wire where it and the purple/yellow wire are joined at the ring term on the coil + and just attached the purple/yellow to the coil. When I tried to start the engine it fires and starts but it immediately dies. I don't have a fuel problem cause I can smell that and when I took the purple/yellow wire off the coil + and went back to the jumper wire that worked originally that wouldn't work either. Same result.

Please provide me some ideas for solving this problem if you have them. I put a call in to Pertronix but didn't hear back as of yet so I will talk with them tomorrow. Is this something obvious I'm overlooking or does this sound like a problem with the Ignitor itself? I did check the coil for spark and have good spark coming from it. The coil is mounted horizontally and is the epoxy model instead of oil. Should this cause any issues?

The engine again is the 1987 version of the 470. MCM 180 3.7 LX inline 4 with closed cooling.

Thanks for any and all help you can provide. It will be much appreciated."
 
The resistor wire was supplyin

The resistor wire was supplying the 9 volt run voltage for the coil. Replace the resistor wire w/a 16 ga. wire connected from the coil + terminal to the wire supplying 12 vdc to the elec. choke.
 
Thanks for the response Guy.

Thanks for the response Guy. A couple questions for you: How come the engine initially ran with just the jumper wire coming from the solenoid directly to the coil +?

According to the Pertronix installation diagrams when using the Flamethower coil with internal 3 Ohm resistor you should eliminate the resistor wire. So you're saying this wire provides a needed voltage to the coil along with the ignition wire coming from the solenoid in order to allow the engine to run.

I can do that but the perplexing thing is that the engine ran with the jumper wire and now it won't.

Thanks again for the feedback.
 
"the ignition wire coming

"the ignition wire coming from the solenoid in order to allow the engine to run."

From wire diagram it looks like that wire is only energized w/the key in the START position. Maybe I'm wrong; hard to see some of the wire connections on schematic.
 
"Guy,

You were right on. T

"Guy,

You were right on. That wire from the solenoid is only energized during the cranking of the engine. It is the resistor wire coming from the choke that provides the run voltage. I did as you suggested by running the 16 ga wire from the choke to coil + and it solved the problem. Engine cranks and runs just as it should.

Now I just have to figure out why the engine temp goes north of 200 on the gauge in the water but on the muffs in the drive it levels off at 180 which is where it should be. That will have to be another topic.

Thanks again for the help and the input Guy.

Dan"
 
"Dan: Glad its running.

&#

"Dan: Glad its running.

"Now I just have to figure out why the engine temp goes north of 200 on the gauge in the water but on the muffs in the drive it levels off at 180 which is where it should be."

The garden hose water pressure thru the muffs is pushing water past the impeller and creating a false water pressure. If the impeller has been in awhile, change it. Also, run a cleaning brush thru the heat exchanger tubes."
 
"Thanks for the input on the i

"Thanks for the input on the impeller and exchanger Guy. I did pull the exchanger last week and cleaned the tubes so that should be fine. I also replaced the T-stat since I had the exchanger and manifold drained. The impeller is the next step I guess. Is this a complicated item to replace? Having to drop the lower unit isn't something I would choose to do but I have the Merc manual and can follow it without any trouble. What tips, hints or tricks would you have in replacing the impeller?

Thanks.

Dan"
 
Pay close attention to the man

Pay close attention to the manual and use OEM parts; take your time. Soak the trim tab bolt o'night w/penetrating oil. Shift into forward gear and drain the oil first. Replace the upper and lower impeller hsgs. along w/the impeller.
 
"Puget,

Thanks for adding t

"Puget,

Thanks for adding to this discussion. I guess I'm confused as to what the temp should be then. The Merc manual states that the T-stat should begin to open at 160+/- and be fully open at 180+/- degrees. I take that to mean that the "equilibrium" or running temp is approximately 180. It also stated in the notes at the bottom of the engine temp troubleshooting flowchart that it is normal to have a direct temperature reading at the temp sender of 180-200 degrees.

How if the T-stat just starts to open at 160 can I expect that the running temp will be in the 140 - 160 range? I'm eager to be informed.

Dan"
 
"Besides looking at the impell

"Besides looking at the impeller I'm thinking I should clean the cooling system. The manual says to use a commercially available automotive cooling system cleaner and follow those directions. What is your collective opinion on that? Is that what you guys do? Is there some "rules of the road" to go by?

I looked at some cleaner the other day and it said to do the draining, flushing and then fill with the cleaner and water. It then said "drive your car as you normally would for 3-6 hours" and then flush the cleaner etc, etc. That seems rather impractical to me and would concern me that my temp would skyrocket with just the cleaner and water in the system.

Tell me what is the best way to clean out the closed cooling system along with hints, tips etc.?

Thanks."
 
Use Prestone or equal "saf

Use Prestone or equal "safe for aluminum" cleaner that only needs 5-15 minutes to do the job. Replace the impeller first.
 
I've never heard of these

I've never heard of these motors running normally at 180. Mine has always run at 140 and some people on the board state to use a 160 thermostat. The blocks in the 470's are aluminum and it's easily understandable why the need for cooler temps. Cast iron blocks are another story.
 
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