Compression/spark test

[zipo16]

Ok so I have a dilema, I set the points (dual points) and was doing the spark test, at first only 1,3 would spark re-adjusted the points and then 1,2,3 spark but not 4.. moved the points a little and 4 sparked but not 1,2,3. re-adjusted it again and got 1,2,3 but not 4 again.... any ideas as to why it will spark alone but not when the rest are set correct? I may be setting these wrong but im not positive. Also could it be a bad ground somewhere?

Also did a compression test with the engine cold since it will not start, 4,3,1 are 90psi and 2 is at 70psi. Did the test twice to be sure. My understanding is that the compression should be at least about 100 could this be because its cold? Does this mean all the piston rings could be worn or that just possibly a burnt valve on 2? I just read about squirting oil into it and seeing if it comes up, what type of oil? just the 2 cycle that I use for the gas/oil mixture?

 

[Daviet]

Re: Compression/spark test

It would help if you listed your model number so that we knew what engine we are talking about.

 

[Barnacle_Bill]

Re: Compression/spark test

What are you working on? If it is a 2 cycle ouboard you do not have valves.

 

[tx1961whaler]

Re: Compression/spark test

Ok so I have a dilema, I set the points (dual points) and was doing the spark test, at first only 1,3 would spark re-adjusted the points and then 1,2,3 spark but not 4.. moved the points a little and 4 sparked but not 1,2,3. re-adjusted it again and got 1,2,3 but not 4 again.... any ideas as to why it will spark alone but not when the rest are set correct? I may be setting these wrong but im not positive. Also could it be a bad ground somewhere?

Also did a compression test with the engine cold since it will not start, 4,3,1 are 90psi and 2 is at 70psi. Did the test twice to be sure. My understanding is that the compression should be at least about 100 could this be because its cold? Does this mean all the piston rings could be worn or that just possibly a burnt valve on 2? I just read about squirting oil into it and seeing if it comes up, what type of oil? just the 2 cycle that I use for the gas/oil mixture?

Sounds like the distributor bushings are worn out on your 1971 Fiat.

 

[fixmyevinrude]

Re: Compression/spark test

I don't think it is a burned valve as 2 cycle engines do not have valves like cars do. Perhaps you need to decarb the engine as the rings may be sticking. As far as the spark problem goes, you will have to find out what that problem is before you proceed any further. I would start by getting the factory manual and checking the procedure for setting the points. If your engine has points it must be an older engine but it may still have a lot of life left. As Daviet suggests it would be very helpful if you would list the model number. Any other basic info will help such as HP, serial number, etc.

 

[zipo16]

Re: Compression/spark test

Wow forgot I didnt mention what it was, sorry guys, I belive its a 1967 johnson 80 hp super sea-horse electramatic. Only thing I can find anywhere is the serial number. No model number. The boat is a 1967 Larson all american 166, I belive its the original motor.

Serial number is J2837019
I think its one of these model numbers but im unsure.

Here are the images of the motor itself.
http://forums.iboats.com/showthread.php?t=428200

 

[zipo16]

Re: Compression/spark test

Ok so I see where the ID tag is supposed to be, there is just 2 rivets and no tag. I got about 6 part numbers off of different items to hopefully help narrow down the model number.

 

[zipo16]

Re: Compression/spark test

Ok contacted Evinrude and he said my motor is a 1967 V4AL19M 80 HP Johnson. I ordered a tune-up set that has condenser and contact sets (new points). They look burnt and I was reading that if they are worn/burnt it can cause irratic spark with the plugs like I am having. Also ordered a new head gasket, hopefully that will be the fix for the lower compression on #2.

 

[fixmyevinrude]

Re: Compression/spark test

I think you are on the right track but I really think you should find a factory manual ( maybe ebay or Ken Cook) so you have the proper procedure. I think it will pay for it self many times over and save you a lot of frustration not to mention the peace of mind knowing you have performed the repair correctly. Just having the proper torque values at your finger tips is invaluble. I would also decarb that engine with some seafoam and see what happens to my compression before changing that head gasket. There is nothing wrong with changing the head gasket but unless I saw some indication that it was failing I would start by decarbing and move on from there. Just my 2 cents. Best of luck.

 

[zipo16]

Re: Compression/spark test

I did get the seloc manual online. The procedure I was using to set the points and compression check was that same as the book I got from the library. Also picked up stuff to decarb the engine today. I figure its a good time to do that since im waiting for new contact sets. Just got off work so I will do it in the morning. Thanks for the advice.

 

[zipo16]

Re: Compression/spark test

Well I just sprayed the decarb into the motor turned it over a few times to help get it into the ring and let it sit 10 min, moved the flywheel by hand which was hard to do before and now its smoothe and easy. Im going to let it dry up or spray it out with air in a little while and then retry the compression test. My guess is they will all improve.

 

[zipo16]

Re: Compression/spark test

Ok so compressin test went great all at 90-95 psi, tossed on the new contacts set the points, all fire! Woo! Then no start... Tossed some gas into the carbs, cranked up after a few tries then died. Did this a few times, then I got my other gas tank from my good boat, cleaned the fuel filter and cranked up the motor and it stayed running so the gas was bad. Only problem is that it throttled up on its own so I adjusted that. But motor kicks out of neutral and into fwd on its own. Is it safe to assume that the clutch dog is bad or going bad? Or maybe the rubber hub? I havent taken anything apart yet to determine the problem. It is a manual shift btw.

 

[jtexas]

Re: Compression/spark test

Did you say "manual shift"?
Is this your motor:

 

[zipo16]

Re: Compression/spark test

Yeah I know its supposed to be an electramatic, but its been converted or replaced I believe. The lower unit that is. It has mechanical linkage all the way down. The Seloc manual says it is a
TYPE V - MANUAL SHIFT LOWER UNIT, SINGLE ENCLOSED HOUSING