Spark Gap Tester and Joe Reeves method and backfire 84 100hp

[edfishing2]

Guys,

I have a question about Joe Reeves timing method. Why do you need to hook up a spark gap tester to set the timing?

My 84 100hp that I have just finished the 10 hr. break in on my 1st rebuild but there is a backfire (I think) every 20 minutes or so above 3200 rpm so I think I have a timing problem. I did not do the link and sync but tried not to adjust the linkages any during disassembly and reassembly. It is also kinda hard to get started for about 8 trys but after warm up it starts fine.

Thanks

 

[boobie]

Re: Spark Gap Tester and Joe Reeves method and backfire 84 100hp

You need the spark gap tester to fire the timing light.

 

[emdsapmgr]

Re: Spark Gap Tester and Joe Reeves method and backfire 84 100hp

Make sure the timer base is moving correctly with the spark advance lever. If you haven't done it, you need to do the sync and link procedure from the factory service manual. If the movement of the spark advance lever is not adjusted properly (in sync) with the movement of the timer base, you can have timing/running issues. If the engine is hard starting when cold, check to see that the choke solenoid is pumping fuel when the key is turned to on-and the key is pushed in. If that choke solenoid does not work it's almost impossible to get started when cold. Pull the small hose off the small brass hose barb on the top carb and see if you get any fuel pulsing out of the hose when the key is pushed in.

 

[edfishing2]

Re: Spark Gap Tester and Joe Reeves method and backfire 84 100hp

The choke solenoid is working.
I have read the service manual over a few times for the link and sync and it must be easier than the wording in the books.
1. make sure timing pointer is correct top dead center. (if someone knows how many thousands of an inch before or after let me know as buddy has a gage with dial indicator).
2. make sure both throttle plates are fully closed.
3. throttle shaft amplifer? what is that? just a rod to make seeing movement easier?
4. throttle cam marks instructions are a little confusing.
5. set timing at idle.
6. wide open throttle stop.
7. max spark advance.