setting maximum spark advance timing

[clifton63]

I just rebuilt my engine 97 200 evi, and need some advice on how to "Bench" set the maximum advance timing. The motor seems to run well at WOT, but I still want to check it. The manual says to run it at 4500+ rpms to set and use a special prop. I am guessing the shops Tank test these with the special prop. I am not going to go buy one of these props, so I thought about setting it while in motion on the lake, but I really became uncomfortable with that idea with the boat moving trying to see the timing, etc. Anyone successfully do this? Any other tricks to do this stationary? Thanks.

 

[oldcatamount]

Re: setting maximum spark advance timing

If that is a carbed motor, there are instructions in the "Top Secret File" at the top of this page that will help you. If not, maybe you could borrow (or rent) a test wheel from a dealer and do it that way. Trying to do it on the boat would be a real trick and you should have a capable driver with you (as well as really calm water)!

 

[wilde1j]

Re: setting maximum spark advance timing

Dealers don't use test wheels on big motors to set timing. Some use dynos, others do it on the water. You can even do it on a trailer with boat suitably restrained or on the water at speed. The Joe Reeves method does it with the motor NOT running, even better. See here:
http://forums.iboats.com/showthread.php?t=228183
You just check it later on the water.

 

[daselbee]

Re: setting maximum spark advance timing

Clif, great to see you have it back up and running.

Some may remember the heated discussions here on this board about ME setting the timing on the water while underway. That is the way I do it.
I hang off the back with a timing light...and...well...you know the rest.

For the Joe Reeves method, you must be sure the QuickStart feature is disabled. Disconnect the white/black wire from the port temp switch to the pack (bullet connector), and ground the pack side. Disconnect the yellow/red wire that goes to the pack from the starter solenoid. Then proceed with the Joe Reeves method.

I have also read where a guy disables Quickstart as above, disconnects the timer base linkage from the throttlearm, making sure the engine is at an idle position regarding the throttle, and then starts it. He then manually moves the timer base all the way to the WOT stop position. (JUST THE TIMER BASE!!!) The engine races up a bit. Then he sets the timing to 2* less than spec. For Clif's engine, that would be 16* BTDC.

After you get it set where you think it is very very close, it is my very humble opinion that you must verify it on the water at 5k rpm.

 

[boobie]

Re: setting maximum spark advance timing

Sorry Wilde1 but I came from a dealership that I worked at for 15 yrs at one time and that's all we used to set wot timing were test wheels. They also use test wheels in OMC/BRP service schools to run their mtrs and do testing on them, WOT timing included. It is probably the safest way to do this. And yes I have also been in the back of a boat setting the WOT timing. The Joe Reeves method also works out pretty good.

 

[wilde1j]

Re: setting maximum spark advance timing

My family owned a dealership for a bunch of years (overf 30). We started using test wheels and soon had a large collection and saw where that was going over time. Since we weren't on the water, we bought a dyno with a few adapters and could handle any motor up to 200 HP and no longer needed a test tank for the big motors and I/O's. The only limit the dyno had was the length of time you could run a large motor at high power (all the energy turned into heat), so the hydraulic oil would get pretty hot. I've used test tanks for motors up to ~ 150HP and props, not test wheels, but the tanks were huge (really long), outdoor tanks. In the later years of our business, it was rare that we used any test wheels. All in all, the dyno was easily the best way to test at high power setting without risk of harm. We must have had thirty or more test wheels when I closed up the business, all with lots of dust.

If we were on the water, we would have run the motors in the water. For backyard mechanics, The Joe Reeves method is the safest, IMHO.

 

[boobie]

Re: setting maximum spark advance timing

I'll go along with the dyno for wot settings but unless you had a dyno test tank with both the dyno and mtr in it you could never get your idle settings correct. With a test wheel and tank, with the proper back pressure on the exhaust system, you could.

 

[wilde1j]

Re: setting maximum spark advance timing

We never used the dyno with a test tank. Used a hose for the motor and another for cooling the hydraulic fluid used with the dyno. Was really LOUD since the motor exhaust was open, but we never ran motors very long and we weren't in a residential area. The beauty was it was really quick to set up. I've often wished I kept the dyno equipment.

 

[boobie]

Re: setting maximum spark advance timing

How did you ever set the idle correctly with out any back pressure in the exhaust system with out water in it. An old '89 looper would idle at 1000 rpm or better on the muffs but put it in the water and it would idle right down.

 

[clifton63]

Re: setting maximum spark advance timing

Clif, great to see you have it back up and running.

Some may remember the heated discussions here on this board about ME setting the timing on the water while underway. That is the way I do it.
I hang off the back with a timing light...and...well...you know the rest.

For the Joe Reeves method, you must be sure the QuickStart feature is disabled. Disconnect the white/black wire from the port temp switch to the pack (bullet connector), and ground the pack side. Disconnect the yellow/red wire that goes to the pack from the starter solenoid. Then proceed with the Joe Reeves method.

I have also read where a guy disables Quickstart as above, disconnects the timer base linkage from the throttlearm, making sure the engine is at an idle position regarding the throttle, and then starts it. He then manually moves the timer base all the way to the WOT stop position. (JUST THE TIMER BASE!!!) The engine races up a bit. Then he sets the timing to 2* less than spec. For Clif's engine, that would be 16* BTDC.

After you get it set where you think it is very very close, it is my very humble opinion that you must verify it on the water at 5k rpm.

Thanks Doug! I was so happy when it fired right up after the rebuild. I have read everyones discussion on this topic. I think the easiest most accurate method for me is to just set the timing with the boat in motion. The way my boat is set up, it won't be that bad. My only concern is being able to see the timing light. Maybe I should pick an overcast day. When I took it out for the first time last weekend, I did take the timing light in preparation for this. But the water was rough on the lake and the engine was running oh so good, that I just passed on doing it. I will try it next time.

 

[boobie]

Re: setting maximum spark advance timing

Get some "white out" and mark the timing marks you want to set to. Use the "white out" on the black flywheel and it works out great. Also find a good calm day for your own safety.

 

[clifton63]

Re: setting maximum spark advance timing

Get some "white out" and mark the timing marks you want to set to. Use the "white out" on the black flywheel and it works out great. Also find a good calm day for your own safety.

great idea! I will post how it came out and any challenges I come across. Thanks!