M10 long cranking frustration

[ineedanother 1,369]

I'll try to make this brief but that's not really my nature 

 

Picked up a 312-8 last year that had sat for several years and had a k301 with a stuck exhaust valve. The valve was in pretty bad shape so I pulled an M10 from a donor. It needed a fuel pump, one charging magnet and the spark plug wire had been eaten by some critters. It had also sat for a couple years as well.

 

I gave it a fairly thorough once-over

• de-carboned, valve adjustment, new head gasket and JB welded a new charging magnet in the flywheel
• oil change, spark plug, ignition coil, air filter
• cleaned the carb, NOS fuel pump, replaced fuel lines, filter, petcock, back-flow valve

 

Changed out wiring harnesses and did the swap. It's been running, smokes a bit on acceleration but has plenty of power and 110 psi compression (no means to do a leak-down). The issue I was having was painfully long cranking to start. I've been fiddling with this for a couple months now and have been at my whit's end. It had seemingly good spark and fuel supply but I went ahead and put an electric fuel pump on it yesterday. Still no help. Swapped carbs with another machine and no change.

 

I went back over everything this morning and found the magneto gap at a generous .016"  . Adjusted to a tight .013" and that seems to have worked  The spark must have been weak so I guess the moral of the story is to not overlook the details and do things right the first time 

[kpinnc 12,016]

6 hours ago, ineedanother said:

I guess the moral of the story is to not overlook the details and do things right the first time

 

I could write a book about this.

 

...and make myself the lead character! 

 

So many times I've chased my tail when the fault was right under my nose! 

 

You did good! 

[peter lena 8,620]

@ineedanother  often found the chronic problem to be in the details , obviousely ,you have been there . found carb adjustments and related linkage movement points , zeroed it in for me . added a fuel check valve to my horses , to hold the fuel right up to carb , eliminating , carb back drain . is there another horse owner close to you ? another set of eyes / thought  might help , hiding in plain sight . can only suggest what I  have done or experimented with . enhance what works , one I  recently sold , sounded like yours , when it left , it started easily / instantly , had  shorted wiring , filthy gas set up , corroded connections . personally , would fuel check valve it , totally closed choke / fuel hold to carb , once I  find the cure , add it to my other horses . hope you find it , pete 

 

[ineedanother 1,369]

Thanks @peter lena this issue definitely led me to address some issues, misdirected as some might have been. I'm a bit of a loner and tend to hunker down in the shop with a  to overanalyze and grease things . This issue if not for the outcome made me bring the fuel supply issue and some other stuff up to where they should be... 

[peter lena 8,620]

@ineedanother  nice progress on that , dare I  suggest ?  having recovered a number of engines , and the obvious neglect ,  add rislone zink  to my oils , use a small measuring cup , add 2 ounces for every qt of oil , initial running , notice oil cleaning / changing , grayish color , time and engine heat , cleans up the oil graying , along with a running ease . been using this in all my engines now , zero smoke , clean oil . only a suggestion , just about every  yard tractor I see , is a neglected / rusty wreck , went the other way , pete

[ineedanother 1,369]

12 hours ago, peter lena said:

@ineedanother  nice progress on that , dare I  suggest ?  having recovered a number of engines , and the obvious neglect ,  add rislone zink  to my oils , use a small measuring cup , add 2 ounces for every qt of oil , initial running , notice oil cleaning / changing , grayish color , time and engine heat , cleans up the oil graying , along with a running ease . been using this in all my engines now , zero smoke , clean oil . only a suggestion , just about every  yard tractor I see , is a neglected / rusty wreck , went the other way , pete

I know we've had these discussions lately and I use Rotella in mine as well as in my diesel generator (3 cyl. Kubota). I just looked quickly and from another site where Shell was contacted directly: "Shell Rotella T Multigrade Oil SAE 15W-40 with Triple Protection Technology, our API CJ-4/SM specification product, typically contains about 1200 ppm zinc and 1100 ppm phosphorous as manufactured." I've used straight 30 weight as well as multi-grade but regardless, I think I'm pretty good with their products 

[peter lena 8,620]

@ineedanother something thats common in any used mechanical part that I  have picked up is , general neglect .often suggest to watch the effects of your recovery points , thats made me try other combinations . rotella has been very good , thing I  notice most , is longer engine heating / oil effects. the hotter the oil , longer run time , also use pto drive , to load that area . see an oil cleaning grayish color , that shows up and flushes itself , after a good long run . also hot oil drain that , that regular drain has made for consistent cleaning , oil always full , no smoke at all , another thing I  don't do  , is to wake up an engine at a screaming rev start . always look for an opportunity to , improve , an nagging issue , thanks for the shout , stay at it , pete

[BESTDOGEVER 218]

Just a quick hack on setting up an ignition module is to use a business card as your gap setting they are about. 010 and that is what most of them are meant to be set at in fact Briggs used to include a piece of card stock in the box.