ice pac

After the months of waiting, I finally finished changing everything and cranked it up tonight. It ran darn good. HUGE improvement over when I first got it. Special thanks to Lars for the carb, it ran great.

Just a couple small problems:
1. Oil temp isn't working. Not sure if it's the guage or the sensor, how do I tell?
2. Backfires at high RPM's. Not sure if its jetting or timing or what. What should I check first?

Aside from those two little things, everything was great. All the work paid off.

BTW- I ran it with just my new Dynomax ceramic headers. No exhaust. :D It sounded like sweet music. :cheers:

7Bob3

1. Check resitance on sensor. Should drop as temp comes up. Does the sensor have 1 or 2 terminals? (Need to know to check gauge)

2. Sounds like a vacuum leak

LAvetteman

Can't wait to hear it Ice. I know you must be excited. :eek:

Smokehouse69

I high speed backfire can be caused by a lean condition, either you are running out of fuel, or you have a big vacuum leak. I don't have a clue on oil temp sensor.

GaryS

Pull the oil temp sensor and put a multimeter on it. If the resistance is infinite, it is probably toast. There should be some nominal resistance value that decreases as the temperature increases. I believe it works the same way as the water temperature sending unit. My water temp unit measures around 700 +/- ohms.
Gary

Twin_Turbo

Pull the conenctor from the temp. sensor and ground it on the block. If the gauge jumps to full readout it's fine, the sender is shot.

Marck

ice pac

I'm not completely sure where the sensor is. Is it on the passenger side of the block under the headers? There is a sensor there and I thought it was the oil temp. Let me know if I'm wrong.
Thanks,
J.thib

Jvette73

When you say backfires at high rpm do you mean popping from the exhaust? Running open headers can cause a lean condition. If its popping from the exhaust change the spark plugs. If one of them is misfiring, the charge can jump posts inside the dist cap and fire the the adjacent cylinder out of time. If there is a crossfire in the cap caused by a fouled or mis-firing plug, then its possible the charge will jump to another post in the cap in its quest to find ground. If a cylinger is firing when an exhaust valve is open, you'll get this popping sound. Been there, done that. Changed the plugs and smoothed right out.

Twin_Turbo

The oil temp sender is located on the oil filter pad. It's just above the filter.

Visible here:



See the brass colored thing sticking out of the block on the filter pad? That's it.

Marck

Vetterodder

Other causes of high rpm backfiring are valve float and too much or too little ignition timing.