Thank you, maybe that was my problem all along. I'll give that a shot.
Davis DUI installation/evaluation
- Thread starter GJCruiser
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Well, I verified it is all wired like this diagram and it is now that I connected the yellow to the tach port on the distributor. Sniper power is coming from under the dash by fuse panel, same location it was getting power when it was working with stock dist.
I’ve gotten the bb lined up with the needle in the timing window.
Dist fully seated pointed at #4
Valves is this position. I can jiggle them very little, fresh rebuild so maybe they’re more snug than usual.
@Coolerman HEI harness wired as per instructions positive to positive battery terminal, ground to ground terminal, fuse installed, black yellow tapped into small black yellow on the harness for coil.
Backfires sometimes when cranking but won’t start. RPMs when cranking are in the 80-90 range. With Toyota distributor I was getting 2-300 range.
Got a few thoughts.
Even though you’re probably close on the timing, the manual says set the engine to TDC on compression which is the window pointer pointing to the line and not the bb. The bb is 7* BTDC and is for use with a timing light when running. And the dizzy rotor should point not at #4 spark plug but a little past it towards #3. I’ll post a diagram in case you don’t already have it.
Also, just to be certain you’re on TDC “compression”, besides checking numbers 1 & 2 rockers to be loose, just go ahead & check numbers 1, 2, 3, 5, 7, & 9 to be loose.
And since you have the valve cover off, you may want to adjust the valves or at least check them using the half & half method also shown in the diagram.
Even though you’re probably close on the timing, the manual says set the engine to TDC on compression which is the window pointer pointing to the line and not the bb. The bb is 7* BTDC and is for use with a timing light when running. And the dizzy rotor should point not at #4 spark plug but a little past it towards #3. I’ll post a diagram in case you don’t already have it.
Also, just to be certain you’re on TDC “compression”, besides checking numbers 1 & 2 rockers to be loose, just go ahead & check numbers 1, 2, 3, 5, 7, & 9 to be loose.
And since you have the valve cover off, you may want to adjust the valves or at least check them using the half & half method also shown in the diagram.
I'm not sure if this is helps but something else to think about. This is from EFi System Pro's website. "Until the engine is turning at or above 400 RPM the fuel pump is shut off and the fuel being injected is based solely on the cranking fuel table. Upon achieving 400 RPM, the ECU turns on the fuel pump and injects the fuel specified by the base fuel map and learn table." This is kind of what I was getting at earlier. If the handheld doesn't show 400 plus RPM's, it won't start. When we figure out why it only registers 88 rpm, the rest will fall into place. This page tells you how to troubleshoot the coil and other components in the distributor if you haven't already. Professional Tips – Performance Distributors - https://performancedistributors.com/professional-tips/ bullet point #4
Also, I know our wiring is slightly different but I connected the b/y wire from the dui to the BIG b/y wire. (on the left side in your picture?)
Also, I know our wiring is slightly different but I connected the b/y wire from the dui to the BIG b/y wire. (on the left side in your picture?)
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Thank you. and sound advice on the valve adjustment. When I had it running just a few weeks ago on the toyota dist I did go through and adjust the valves. Having just had the motor rebuilt I thought they would be dialed, but they were not.
I will try setting the needle to the line and adjusting the dist. Which manual did you get this out of?
@derail what model year is yours? Maybe I should try that other wire. I've wondered why I was only gettting 80-90 RPMs. Something is up.
1975 fj55. Same sniper and same distributor as yours.
Looking at the sniper screen you posted, 7.9v, charge your battery?
I agree. Snipers are temperamental about voltage. If you charge your battery, don't try and start it with the battery charger hooked up. Always disconnect it before cranking. One more thing, those blue power taps are not great. I understand just trying to get it running, but when this gets sorted out, I'd go back and re-do a connection using those. The snipers are also temperamental about wiring, and I'd hate for you to have problems down the road with something like that.
I take diagrams out of manuals or from posts by others and with Photoshop I’ll enhance, declutter, highlight, combine, etc. That dizzy & valve adjust diagram has been around quite a while. I can’t remember if I had a hand in it or not.
When I time with the timing light, I have the bb at the left side edge of the window. I’m guessing it’s around 10 to 12 deg BTDC and seems to be fairly popular.
Here is a pic of where my rotor points when at TDC compression. (pointer on the “line”).
Here is a pic of where my rotor points when at TDC compression. (pointer on the “line”).
yeah i thought the same, have it on the charger.
Never run a freshly built motor starting out with a sniper. It will run rich and prevent the rings from bedding in. Also only use conventional oil that's high in zinc or a zinc additive. No synthetic.
Agreed. I used that tap just to get it running. Planned to solder connections after getting it all figured out.
Well shoot, don't have a stock carb. I am running special high zinc break in oil the shop recommended.
cstav86
SILVER Star
My DUI points in the exact same spot as yours @residualboulders ... At #4, not just passed it like steamers and the diagram shows. I tried multiple times to re-seat it to match the diagram, but couldnt get it to point right past #4. From reading @wngrog statement, it doesnt matter where the order starts, but mine had to be in specific places for it to fire.
cool thanks. No oil cooler?
cstav86
SILVER Star
Not on the F1.5.
Man. I have done 10+ new 2Fs with Snipers in the last 3 years and I have never even considered not using a Sniper to break it in. I can’t even imagine what a hassle it would be to use a carburetor and then switch to a Sniper.
Fuel pump. Linkage.
Agree on the Dino with Zinc though
cstav86
SILVER Star
I messed with mine a bunch tonight and even put my original dizzy in. The original dizzy points just past #4 exactly like the diagram, but the DUI points at #4. Even rotated the engine to see if I was off and it sat the same. I can get it to point just past #4, but the DUI won’t seat all the way down so that doesn’t work.
Seems to run well when I put it all back together.
Are both red wires on the DUI on the right when you plug them in?
Seems to run well when I put it all back together.
Are both red wires on the DUI on the right when you plug them in?
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Don’t run the DUI not fully seated. That’s the oil pump
