My D15 Series 1 Build

PO2 it started in 60.

Every D-15 was always Persion #2 with cream grille and wheels.

A lot of that info is in Norm Swinford's book "Allis Chalmers Farm Equipment 1914-1985"
I think a lot of guys here have that sitting next to their Bible.

Break in is done! I started out with it set at f25 for timing but it wouldn't hardly pull any load and was only making 21hp. I set it back to the advanced mark where I had originally ran it for years it made 39 hp and 289 ft lb's of torque. I advanced it past my original mark and it brought power up a hair but I also heard a little detonation so I took her well back off of that.

Not sure why it runs so crappy at F25.

Yeah I thought I must have missed something as well but verified it again. Runs like total garbage at "F25". It's very clear in the belhousing hole as the flywheel was polished up nice from a mouse nest in it. Not sure why it would be doing this. I went a degree or two less than the original setting that we had it at for years with no burned piston issues on them. Could something with funky points be throwing off my readings? When I had the engine at TDC on the front pointer (which could be my mistake) the points are well away from the lobe on the dizzy to get them to open. It runs great. Good throttle response and idles just great.

I bet it gets some looks from the neighbors when it's out there running! Don't worry about that though. Looks like you've got some support from about everywhere!

Are you sure your advance mechanism is working (not stuck)??   Should be F-25 at wide open throttle and near/close to TDC at a very slow idle.

I don't recall seeing a TDC mark on the flywheel at idle. I found the F25 mark at wide open throttle only in the window. I took the plate below the points off and had lightly lubed it and cleaned the centrifugal advance system. Grabbing the rotor and turning it forward, the advance feels nice and smooth and using the timing light you can see the timing advancing and retarding based on engine speed.

Something's really odd. With it set at the F25 (at wide open throttle) the engine almost stalls just lifting the lift arms. With the distributer turned 1/8th inch clockwise (advanced) the engine at idle does not even pull down the RPM when using the lift. This advanced timing setting is where the tractor had been set for the last 25+ years with no burned pistons so maybe its ok at that setting. when I was testing it at full rpm and full load I had to turn it another 1/8 inch advanced to start hearing a tiny bit of spark knock so I feel like I am a ways away from detonation issues.

I do all kinds of diagnostics on automotive engines and rebuild them and tune them and diesel engines all the time so timing isn't totally foreign to me but I don't mess with points very often which I wonder if I am missing something related to them.

I don't plan on converting this to electronic ignition as it runs so good with points and I have never had an issue with it starting even with a wore out engine in the past.


Edited by bigredisb - 30 Aug 2016 at 8:45am

I would set it where it runs good with no detonation. Your dyno will tell you where your best timing and carb setting is. Like you said, "that's where it always was"

That's pretty funny about the key. The tie rods on my 45 were pretty froze. I spent a little effort in getting them apart, then just bought 2 new ones that were good and tight for about $60 each. No steering slop now.

When using the timing light, you are shining it thru the 1 inch hole in the right side of the bellhousing??

DrAllis wrote: When using the timing light, you are shining it thru the 1 inch hole in the right side of the bellhousing??

Yes. Timing marks are cleaned up and clearly visible with the light while its running. At idle the TDC mark lines up in the window next to the little rough casted pointer and at full throttle (2100 ish rpm) the "f25" is clearly visible. When set to that it stumbles and carries on and the dyno proved it fell on its face. Would only make about 21 hp at that setting. I am maybe only a degree or two over the F25 mark and it runs clean and smooth and power was back up into the high 30's.


Edited by bigredisb - 31 Aug 2016 at 3:19pm

bigredisb wrote: DrAllis wrote: When using the timing light, you are shining it thru the 1 inch hole in the right side of the bellhousing?? Yes. Timing marks are cleaned up and clearly visible with the light while its running. At idle the TDC mark lines up in the window next to the little rough casted pointer and at full throttle (2100 ish rpm) the "f25" is clearly visible. When set to that it stumbles and carries on and the dyno proved it fell on its face. Would only make about 21 hp at that setting. I am maybe only a degree or two over the F25 mark and it runs clean and smooth and power was back up into the high 30's.

I also adjusted the carb settings to see if that could somehow be impacted by timing but it made little to no difference.

Could the different pistons and compression be impacting the timing a couple of degrees? Its like F25 is just on the ragged edge

Dan73 wrote: I think Joe said he has the same poisons you have and he didn't have any trouble with timing. I have been thinking about this alot one stupid question but when you setup your timing light you use the spark plug closest to the front of the motor correct? Just want to make sure you are #1 not #4.

Ha ha ha, Yeah I have been using #1 all along BUT the other night I looked it up to make sure the front cylinder was indeed referenced as number 1.

Sure, when I get a chance I can check compression.

Here is a video of the lift arms running. Seem very jumpy. The lift arms bouncing around make it look worse than it probably is:
Hitch raise video