1977 175 'rude power pack shocks you

[Crankstomp]

I am the proud owner of a 1977 Evinrude 175 model #175749S. It starts and idles OK. It revs up fine under no load. When under load, it sometimes runs fine and sometimes will bog down and die at around 1300-1500 rpm. I suspected I had a intermitent ignition problem. Today while testing the voltage regulator(Tach acts crazy), I touched the port power pack cover and it shocked the heck out of me. I put a voltage meter on it and it showed over 200 volts. Are these related, and if not can you help me with each problem.

 

[OBJ]

Re: 1977 175 'rude power pack shocks you

Hello Crankstomp and welcome to the forums...<br /><br />Yep...could be the problem. Sounds like the pack is robbing that bank of cylinders of spark.<br /><br />With the engine not running, take the cover off the pack and look for any of the leads that may be shorting to the case. If nothing is obvious, start the engine, with the cover off of the pack, and see if you can see anysparks any where. <br /><br />You could also swap the packs and see if the problem follows the pack you got jolted on. If it does, replace it. It's probably grounded internally.<br /><br />Keep us posted.

 

[Crankstomp]

Re: 1977 175 'rude power pack shocks you

I pulled the cover off and there were several wires that could have been shorting out. I pushed them down and cut a piece of gasket material to put under the cover(the other pack had one). That solved the shocking problem, but I test ran it and it still bogs sometimes at around 1500 rpm. The first thing I did(before the first post) was to pull the carbs and clean them. What is the best way to test spark strength on individual cylinders?

 

[Hooty]

Re: 1977 175 'rude power pack shocks you

Check spark with a spark gap checker. I know AutoZone handles a little single wire tester, Stevens Instruments sells a multi-wire tester that's a good one and several here on iboats have made their own. Try the 'search' function. I think your manual probably sez that that engine should throw a big ball of blue fire across a 7/16" gap.<br /><br />c/6<br />Hooty

 

[Okie]

Re: 1977 175 'rude power pack shocks you

Crankstomp, Walleye are hitting and we are in the same boat. Could be a good fall bite! HA! Ha! Let me know. Okie

 

[OBJ]

Re: 1977 175 'rude power pack shocks you

The spark to each cylinder should jump at least a 7/16" gap with a hot white lighting like spark. So if you do rig a tester, use the above gap to measure the strength. Also, if you do have weak spark, notice which bank it's on.<br /><br />Edit: When you cleaned the carbs, did you hose out all passage ways with carb cleaner and follow up with compressed air? Are all fuel lines still flexible and not hard? Hard fuel lines tend to lose their grip on connection points. Could suck air.

 

[Crankstomp]

Re: 1977 175 'rude power pack shocks you

I feel like that little orange guy beating his head against a wall! I checked the spark strength and they seemed to be fine. I took it to the lake yesterday and does the same thing. Most of the time it runs fine, but it sometimes bogs at around 1500 rpm. When it bogs like that, it idles kinda rough like it is missing. Most of the time when it does it, you can rev the engine up with the warm-up lever for a little while, and then it goes back to running OK. The tach worked fine all day at the lake. I checked the spark strength this morning and it seemed weak on the port bank. I checked the output coil per the manual and I think its OK. I swapped the power packs because I thought it might be the port pack. After swapping packs I had fire on all cylinders, but then again, this thing comes and goes. Now the tach doesn't move except when you rev it up with the warm-up lever. When you rev it up, it stays on zero until you move it back down and then it will move up to around 1500 rpm and come back down.? I am at a loss.