'69 Chrysler 35HP - How To Set Timing?

[SeaStar69]

Hi folks,

Does anyone know how to set the timing on this motor without the special tool listed in the service manual? The tool screws into the spark plug hole and lets you establish when the piston is at 32 degrees before TDC. Then you use a test light to adjust the timing. If anyone is familiar with the factory tool and knows the spacing on the rod between 0 and 32 degrees, I can probably make one myself out of an old spark plug.

Thanks,
Jim

 

[wickware]

Re: '69 Chrysler 35HP - How To Set Timing?

I have had a 1970 35 hp Chrysler since 1984 and timing has never been an issue vs dirty points. For some reason many want to play with or adjust the timing which is the last I would want to tackle. Usually worn parts or bad points are the issues vs the timing being off.

1. Why do you feel the timing is off?
2. Have you pulled the flywheel to know your points are good and gapped to .020?
3. My suggestion would be to check for wear before tampering with the timing.

 

[SeaStar69]

Re: '69 Chrysler 35HP - How To Set Timing?

The points and condensers are new and gapped at .02". I spent a few extra bucks and got some NOS US-made parts. Plugs are new, too. The compression is in spec, the carb is rebuilt and properly adjusted and the fuel pump is rebuilt. Basically, went through a major tune up and the motor has a particularly bad miss at idle. The timing is the last thing I need to check. Per the manual, the point of throttle opening is synchronized with the timing advance - it looks like someone has fooled around with this in the past, probably to compenstae for bad points. My latest thought is to measure the stroke with a depth gauge and calculate the amount of piston travel that equals 32 degrees BTDC. Then I could set the timing with a test light.

 

[wickware]

Re: '69 Chrysler 35HP - How To Set Timing?

If you are double sure on Original Points Condensers are to specs and adjusted .020 to specs and etc (you might have a timing issue). A rough test that I use was related in a thread listed last month related to timing using the flywheel teeth. Search Wickware (here) and the attach pic of marked flywheel will be attached. My machine is too slow but I?ll try to get back tomorrow by noon.

 

[wickware]

Re: '69 Chrysler 35HP - How To Set Timing?

I hope the .02? on the points is a mistake or that is some of the problem. IMO the timing is the last to adjust unless you find it to truly be off.

The spark plug hole dial indicators at the site below (very bottom) is handy if you have or can get to check the timing related to the points opening.

There is a depth gage on this site shown and specific for Chrysler timing, The flywheel tooth method for checking timing and advancing is what I?ll try to link you to.

Good Luck and please share your results vs just going away as many w/o feed back.

I c/n find the newer post related to timing using the flywheel teeth but I did find this old one below. I?m out of time and maybe you or someone else will spot the newer post related using the Chrysler flywheel teeth related to check timing and timing advancing (on 35 -45 hp on that post). Too Much To Chack!!

http://forums.iboats.com/force-chry...-flywheel-related-your-timing-met-366955.html

spark plug hole dial indicator - Yahoo! Search Results

 

[Nordin]

Re: '69 Chrysler 35HP - How To Set Timing?

The timingadvance should be 30dgr. BTDC at WOT. Count the tooth at flywheel divaid with 360 and multiply with 30 then you have how many tooth before TDC you have the timingadvace. The spark at top plug should come at this point when the engine is at WOT.

 

[SeaStar69]

Re: '69 Chrysler 35HP - How To Set Timing?

OK - so I spent the past hour working on the motor and discovered a couple of things. First, there was way too much timing dialed into the motor. Using the flywheel as a guide, it was around 39 degrees between idle and WOT. Hopefully that explains the miss at idle. By adjusting the set screw on the advance bell crank, I was able to reduce the timing. I think Nordin is saying to set the timing at zero advance with the piston at TDC and the throttle at idle position. I believe that this initial timing setting is accomplished by adjusting the threaded rod that's attached to the breaker plate. Total timing at WOT is then determined by the set screw on the advance bell crank. Am I taking the right approach?

 

[Nordin]

Re: '69 Chrysler 35HP - How To Set Timing?

I will clear some things up. Always measure/set out from cyl.#1 (top). Determine the TDC (where the piston does not travel more upwards) with a screwdriver in top hole. Mark at flywheel with a ref.poit at powerhead. Count the tooth, diviad with 360 and multiply with 30. This is the point (30dgr. BTDC) when the spark should come at cyl.#1 at WOT, mark at flywheel.
Now measure with a multimeter (static timing) or use a timinglight (dynamic timing) set the engine at WOT. (static timing) the meter should go from closed circuit to open (points open) at this mark on flywheel when it point to ref.point at powerhead.
(dynamic timing) the timinglight will make the mark and ref.point line up.
If not, you adjust by change the length of the timingrod that advances the breakerplate due to the throttleadvance.

 

[wickware]

Re: '69 Chrysler 35HP - How To Set Timing?

I?m to slow to follow the math, "please show it", if I have 83 teeth. The figure I'm getting is not making since. BTW, I'm not having a timing issue (with my 1970 35 hp Chrysler) but want to document this method.

Thanks!

 

[Nordin]

Re: '69 Chrysler 35HP - How To Set Timing?

wickware if you have 83 teeth round the flywheel 83/360x30= 6,91 teeth. 30 dgr BTDC is 6,91 teeth.
Am I wrong?

 

[wickware]

Re: '69 Chrysler 35HP - How To Set Timing?

Got IT! 360 (Fly?s Dia) into 83 (number of teeth around Fly) = .230 X 30 = 6.91 teeth (= 30 degrees BTDC).

Is the spark plug dial indicator the tool that would commonly be used for this task? We used the method to set points on old tecumseh mowers that were strict and would give a good kickback if off. Versus Briggs were friendly and could be easily set w/o the dial indicator.

 

[SeaStar69]

Re: '69 Chrysler 35HP - How To Set Timing?

Nordin - thanks for the pointers, it makes perfect sense to me now. I'm going to try to get the motor in the test barrel this weekend and see how she runs. Can't wait to tell folks that someone from Sweden helped me tune the motor!

Jim

 

[wickware]

Re: '69 Chrysler 35HP - How To Set Timing?

My 55 gal test barrel has been good since 1984-85 for seasonal start up, checking idle and pumping water but not god for any power testing. I learned after a few 120 mi trips to find bad power that I need to power test in the local lake etc even w/o leaving the trailer. Leaving the trailer is better to see if you come out the hole w/o hesitating or bogging and get up on plane quick.

 

[Nordin]

Re: '69 Chrysler 35HP - How To Set Timing?

wickware Little more clearing about the numbers. 83 (teeth around the flywheel) 360 (a circle is 360 degrees) 30 (timingadvance at WOT) . 6,91 teeth is equal with 30 degrees.
Make note that it is 6,91 teeth to the left of zero point thats BTDC.

BTW wickware. A dialindicator is perfect and more exact then the teethcount method.
I have made a tool from an old sparkplug bored a hole in the centre and put a steelrod in.
Marked a zeroline (TDC) and then marked a 30dgr line (BTDC) on the rod.
Do not know the exact distance but something about 7,6 millimeter I think (I am in Europe and use millimeter instead of inch) 1 inch is 25,4 millimeter.

 

[SeaStar69]

Re: '69 Chrysler 35HP - How To Set Timing?

Gents,

Just wanted to report back in - she's purring like a kitten. Had to make a 1/2 turn adjustment to the breaker plate rod and the idle evened out nicely. Idles nicely in and out of gear. I goosed the throttle once and the revs shot right up. A little more glass work on the hull and it's off to the lake dyno.

 

[wickware]

Re: '69 Chrysler 35HP - How To Set Timing?

Thank! Feedback is needed. Good Luck on the Glass Work. Please share your results after you run it on the water.