Starting Problems

[Newman"75]

I have a 1975 Johnson 75.
I got it fairly recently, for a while it ran well. It will now just run a battery down attempting to start. Not even a hint of starting.

I've checked compression at 112.5/ 125/ and 120 lbs. per cylinder respectfully. When checking for spark off the individual plugs, I get spark fairly regularly off the # 1 and # 2 plugs, and # 3 seems to be somewhat there, and sometimes not.
The plug coils/ (wires especially) look OEM and definitely look as if previously "jerry-rigged". But I have read some threads which refer to Power pack replacement.
How do I determine a bad Power Pack? And would anyone recommend total replacement of plug coils. Or a coil test?
Also, I had been mixing my fuel at 40:1, which after reading some posts I guess I should have mixed 50:1?

These are the plugs that came with the motor, and look a little oily. Probably all the un-burned fuel. I know I should replace them, but at the moment, I think the other ignition components need to be ruled out.
Can anyone help suggest my trouble-shooting.
Thanks!

 

[HighTrim]

Re: Starting Problems

First off ,welcome to iboats!! To your problem. I have a feeling your no start issue is due to more than 1 demon. Your compression looks ok, cylinder 1 a bit low, but not enough to cause a problem. Your spark issue definately is. If the plugs are shot, replace them. If i understand you correctly, you are getting spark, its just weak or sporatic correct. That could be due to a number of things: the charge coils, power pack, key switch, 10 way connector, etc... Your spark when running good should jump 7/16 of an inch with a strong blue ZAP!! What do u mean by "jerry rigged"?? And yes, mix your fuel/oil at 50/1.

 

[Barnacle_Bill]

Re: Starting Problems

Highly recommend you get a manual. You can eliminate most of the parts through testing as directed and verify the jerry rigged wiring. Also look for loose/dirty connections.

 

[Newman"75]

Re: Starting Problems

Thanks High Trim,
I was able to achieve about 1/8"- 1/4" spark with some inconsistency. And though rarely, I could get (can't remember which one), but yes, on an occasion I could get an arc to travel about that distance (7/16").
"Jerry- rigged" were the plug boots, which are slit in 1/2, and electrical taped back together. I guess previous owner didn't want to buy the coil/wire units. Also, there is evidence of cable wear as there is plenty of tape around the plug wires.
I have already replaced the ignition switch with a new one from i-boats, which helped a previous no-starter problem. Cleaned all visible electrical connections too.

One thing I neglected to describe in my previous post was that it also smokes big-time on start-up (blue-ish). Then clears up after running. It is after I stop for awhile that it refuses to start too. I don't smell heavy fuel, I'm not sure, but flooding motor may be going on too. The plugs were black and wet also. That is why I mentioned my (incorrect) 40:1 fuel mix because I thought I may have been running too rich.

Thanks for your fast reply- I couldn't reply back right away because "she who must be obeyed" called me up for dinner.

Thanks, I'll keep reading posts- very informative repair forum- Thanks again

 

[Newman"75]

Re: Starting Problems

Thank You Bhile,
I appreciate your recommendation, however I was hoping for a bit more insight.

 

[tashasdaddy]

Re: Starting Problems

here are some test on page 29 -31, C & P without the "

"http://www.boatpartstore.com/page29.asp"

 

[Newman"75]

Re: Starting Problems

Thank You Sir,
It'll be a week at least before my engine manual arrives, and I can't sit doing nothing. I'm terribly addicted to boating!
High Trim was right, I'm sure there are several problems (Demons!), But what a great boat she is when she's running - Never believe it for a 32 year old!




************
1975 Newman / 75 Johnson Stinger
U.S.S. Independence CV-62 (de-com)

 

[mikesea]

Re: Starting Problems

HELLO NEWMAN.since the coils look jerry rigged to you they are,I believe your plug wires are part of the coil,that is they dont disconnect,but its been so long I could be wrong,to really do it right,you should replace the coils and wires,but,if you dont,check that any connections,grounds,the smaller wires to the coils ,are all connected with clean connections,over time ,especilly if splices were made,the connections can corrode due to the moisture atmosphere and fail,If someone can come along here and advise as to whether you can up grade to a newer style coil that had the plug wire as a seperate unit (AND THAT IS IF YOU HAVE THE STYLE IM TALKING ABOUT)with a good set of wires and good solid connections your spark would likely improve.As for the starting,if your spark is poor,its likely that you do end up with a floodong situation also,is your choke working properly,you do need a choke on these engines,if you dont get a good full choke ,check the choke solonoid and spring that it is adjusted to give full choke and releases the choke full open,Does your battery run down quick,how old is it,are you sure it is good,the eng neds to spin fast to get proper spark,if you have a battery issue ,it could be a part or the problem

 

[Newman"75]

Re: Starting Problems

Thanks Mikesea,
Very Good! Yes that was going to be my next question. I was wondering if the plug wires could be replaced separately of the coils. They look as if they are sealed on the coils though, and I believe I would muck them up if I were to try removing them. (destroying the interior coil connection) They appear factory attached.

Also, yes choke function is good ,fast, and butterfly's seem to seem to seat well over intakes. Idle speed control also seems good.

I have had doubts as to the battery. (or I should maybe refer to stator/rotor) What I mean is, the guy I bought it from emphasized that he had just put in a new battery. That got me wondering, Why? I metered the terminals while engine ran and read about 12-12.5VDC. Shouldn't it be more like 13-14VDC? Yes, ( to your question) because it does seem to run down quickly.

Thanks for your help!
************
1975 Newman / 75 Johnson Stinger
U.S.S. Independence CV-62 (de-com)

 

[mikesea]

Re: Starting Problems

When you get it running ,do another test across the bat.terminals to see if the voltage raises,it doesnt put much out at idle,but you could have stator problems,that is where your charging and power for ignition comes from,there are tests defined in manuals and on this site,search stator test,also,do another post requesting info on "coil swapping"I believe you can upgrade to the better insulated coils with seperate spark plug wire,I highly suggest you do,you plug wires are ancient and will be a pain in the a**if not now soon.As for the battery,best charge is a long charge,if its new it should be fine