What would try next - Running like crap

[roadsterdude1600]

It is cold in the shop, so before I try one more time to do the same things over and over hoping for a different result, I thought I would seek enlightenment from the forum. Here goes:

Newly rebuilt R-16 stock 1970, but desmogged and set up like a "66 with Alternator on right, Gary Boone dizzy, and currently have a set of '66 carbs mounted with no fuel return lines. So basically an early 1600 set up. A little history:

Initially started and ran the engine while still on the frame before mounting the body. Ran fine though I knew I would need to dial in the carbs once it was all buttoned up. After getting the body on and installing the hydraulics and fuel tank and lines, started and ran again, this time doing a rough timing and starting carb adjustments. idling nicely and ready to test. Discovered that I had installed the clutch plate backwards and unable to get the car in gear (long story - see thread on this forum). Pulled the engine and reversed the clutch plate, reassembled and ready to test. Not running as well, but still idling OK. fiddled with carbs and tried to test drive, but would not accelerate - died under throttle. More carb work - no joy. getting fuel just fine in both lines. Hard to get a good timing light reading, so I re-checked my distributer assembly and seemed to maybe be a tooth off - closer to noon than 11:25. I pulled the gear and adjusted the oil pump to 12:30 and realligned the distributer gear to 11:25. (Y'all know how hard it is to get that sucker engaged - ugh!). Finally there, all looking good and it barely starts now and just kind of chugs. This was all with my home-rebuilt '70 1600 carbs. So I cleaned and refurbed a pair of early 1600 carbs known good and put them on. Same story. It is getting fuel. It is getting spark. Looks like dizzy is firing at the right places, both set of carbs seem to function at least as designed, if in need of final tune, which I cannot do until it at least keeps running a while. Oh I also readjusted the valves which were OK.

Next up I plan to go back to the well with pulling the dizzy and starting from scratch there. Feel like I have done everything but it still gets worse. Any thoughts while I am inside keeping my feet and hands warm?

[Gregs672000]

I take I that you have not been into any internals in this engine, so we can assume the timing chain and gears are correct (right matching gears and timing chain installed correctly). I suspect spark. If it were fuel it would backfire out the carbs if way lean, or chug and foul spark plugs (check what they look like first thing since you mention it) if super rich (dark could be missing spark too). No timing light... you're guesing! So, either get a light on it, or static time it, or just keep rotating the distributor a few degrees as it is cranking/running (most likely needs more advance) to see what happens.

If you want to static time it, turn the engine by hand to get #1 piston is on its COMPRESSION stroke (may need to confirm by watching what the valves are doing... all should be shut... ask if you need help) and set the pointer and crank marks to somewhere between the 15-20 degree marks, then turn the ignition to run (on, not cranking the starter) and with the #1 spark plug wire grounded to metal (screw driver inside the plug wire to the valve cover for example) rotate the distributor until #1 sparks, then turn the key/ignition off and lock the distributor down... engine is now "static timed" and in the ballpark so you can finalize it. Also, make sure you have a 1 3 4 2 firing order on your cap (counter clockwise rotation as I recall). You really do need a timing light to make sure your initial timing is correct. Then use the light to confirm the timing is advancing as you rev the engine. If not then there may be something wrong with the mechanicals of the dizzy.

Report back!

[Gregs672000]

Regarding the distributor... realize the dizzy body itself does not care where it is, only that the SPARK occurs when it's supposed to, and that is determined by the rotation of the dizzy creating the condition inside such that the internal parts line up and fire the plug when the engine needs it. In other words, being able to bolt the distributor "body" down does not mean it is timed correctly... it's just how it is secured. Getting the slots on the gears to line up (11:25) is so the dizzy body itself can be bolted down and allow some rotation left and right to align the internals and change the timing of the ignition event. As long as you're able to get the initial spark for #1 to fire at 16 degrees (idle timing for R16 I think) and can then bolt down the distributor body it will do what it's supposed to do... distribute the spark at the right time (16 initial, then progressively advancing about 20 degrees) to the correct cylinder.

[Gregs672000]

I read now the engine was newly rebuilt... by who, and what do you know about it? Many have discovered that there are two different set of timing gears for the crank and cam... SAE and Metric. For now, we'll assume it's ok.

[roadsterdude1600]

Wow, thanks for the quick responses. Yes I plan to start over with the distributor as suggested. When it was running (pretty good, but not perfect) it was fouling the plugs rich, black and wet, so I knew I had some carb work to do, but then I lost the ability to get a decent idle, as I went along. I do have a timing light, and had it reasonably in specs earlier, though the advance did not look right, now I cannot even get it idling enough to try a timing light. I did the rebuild myself using the same parts from the engine. Actually a "refresh" since the engine was remarkably fresh. The clock showed 52,000 and I believe that was right since after hot tanking the block no boring was needed. I used the stock pistons with new rings rods bearings and polished the crank. New camshaft bearings and the same timing gears with new chain, so all metric on a 1970 engine. Great Questions. I would fully question my wrenching skills except it ran so well on initial start up and early testing. I must have fiddled a little too much thinking I was a tooth off on the distributor. That's where I am going to start, and static time as Greg suggests. I'll report back when I get back out to the shop. Thanks!!~

[SLOroadster]

I have to wonder if the initial issue was stuck chokes on the SUs making it run super rich? This is a common issue with SUs and easy to overlook.

Yes, verify your distributor timing, and go from there. Make sure the chokes return to their upright position when closed.

Will

[david premo]

One thing you might want to check is the rear carburetor nozzle, years ago I had a guy call me about a rough running engine after he pulled it out and put it back. I had rebuilt his SU’s several months before and tuned them in perfectly. Then he pulled the engine so some work could be completed and after that the engine ran very rough. So I went ahead and looked at the carburetors and the rear carburetor nozzle was bent from contact with the steering column. Changed the nozzle and all was good. So with the nozzle being bent it was in a constant state of choke on.
Dave

[Gregs672000]

Ok good, and very good suggestions by all. If the plugs were fouled go ahead and swap them out for a clean set... you can always soak the fouled ones clean, you'll want them someday anyway. With what you're describing it certainly could be over-fueling, but do pull the plugs and see what they look like (all four the same?) since you tried two sets of carbs. Onward!

[redroadster]

Sure the/a piston slide isn't hanging up briefly
But the way a shop would address it cold compression test, tells alot
Someone at the rear exhaust to see if strong gas fumes emerge cranking
And see what comes out of the SP holes cranking. then get into electrical if they were good timing , I crank in darkness to see if arcs are happening

[Daryl Smith]

Check the carb floats and float level as well.

[jrusso07]

My thoughts align with David's. If ran "okay" before engine was pulled for clutch fix, something must have happened during the engine removal/install process. Sounds like timing (ignition or valve) but carbs are a close second. This carb write-up by Keith Williams has always helped me get my carbs sorted out. https://www.311s.org/pmwiki-311/pmwiki. ... sNewSuTech

Be sure to scroll down as the write-up is below the topics index

[redroadster]

If you've got a good E brake
I'd try a power balance test
Pulling a sp wire at a time when running ...with plugs out what's the turning torque of the crank

[roadsterdude1600]

I got back in the shop a bit yesterday and started at square 1 with making sure I have the dizzy gear properly engaged at the oil pump and everything lined up. Re-did it numerous times until I was satisfied with the 11:25 position. I am pretty sure I am on the compression stroke because the valves on # 1 are both closed (ie no valve lash, stems high and pressure against the valve springs. (let me know if that is backward, because I think that means closed). Eyeballed the alignment of stator/reluctor at 16 degrees BTDC and got them dead on. That should get me started and running well enough to use the timing light. Need to button up and start. Am I correct about the combustion stroke? More tomorrow!

[Gregs672000]

Should be correct on the compression stroke. If you were to continue the rotation the next valve or push rod to open/move should be the exhaust valve.

[redroadster]

With it in ,turn the engine 720° then see it the frt edge of the dist rotor is at the caps #1 post , sure it's not flooded ? The batt turns the engine over at a good speed ? What kind of spark are you getting , peerless makes a spark checker $20 that's a must have for a tech for this , did you try in the dark to see if an arc is leaking , it is getting fuel ? You have a timing lite what's it show cranking ,ya you need a quality assistant to help
Post a video of it